🏷

Classifications

Harrison's Part

📘

Definitions

2

Clinical diagnostic criteria for Dent disease

The long-standing three-part clinical definition, set out in the 2010 Orphanet review and still the reference frame in the 2025 recommendations. All three parts are required. Note that the 2025 guideline goes further and states that hypercalciuria is not mandatory, so the criteria are best read as a high-specificity case definition rather than an exclusion rule; genetic testing is what confirms or excludes the diagnosis.

DIAGNOSTIC_CRITERIA

Inclusion criteria

Low-molecular-weight proteinuria at least 5-fold above the upper limit of normal
Hypercalciuria above 4 mg/kg per 24 hours, or a spot calcium/creatinine ratio above 0.25 mg/mg
At least one of nephrocalcinosis, kidney stones, hematuria, hypophosphataemia, or renal insufficiency

Show evidence (2 references)

PMID:20946626 SUPPORT Other

"The clinical diagnosis of Dent's disease is based on the presence of all three of the following criteria: (i) LMW proteinuria (elevation of urinary excretion of β2-microglobulin, Clara cell protein and/or RBP by at least 5-fold above the upper limit of normality); (ii) hypercalciuria (> 4 mg/kg..."

The criteria set quoted verbatim, including the quantitative thresholds recorded above.

PMID:39794284 REFUTE Other

"Although hypercalciuria is the second most frequent finding in DD, its absence does not exclude a diagnosis of DD."

Refutes treating the hypercalciuria criterion as mandatory, which is why the description qualifies the criteria set.

Case-finding trigger for genetic testing

The 2025 guideline's operational trigger for sending CLCN5 and OCRL sequencing. It is deliberately broader than the diagnostic criteria, because the commonest way to miss the diagnosis is to read nephrotic-range tubular proteinuria as glomerular disease and biopsy the patient instead.

CASE_DEFINITION

Inclusion criteria

Male with isolated and persistent low-molecular-weight proteinuria
Male with mixed proteinuria in the nephrotic range
Male of any age with persistent low-molecular-weight proteinuria plus any feature of proximal tubular dysfunction, nephrolithiasis, nephrocalcinosis, rickets, or CKD

Show evidence (2 references)

PMID:39794284 SUPPORT Other

"We recommend genetic testing of the CLCN5 and OCRL genes to confirm the clinical diagnosis of DD1 or DD2 in the following situations (Grade B, strong): Males with isolated and persistent low-molecular-weight proteinuria, or mixed proteinuria in the nephrotic range."

The guideline's testing trigger, quoted with its grade.

PMID:39794284 SUPPORT Other

"Low-molecular-weight proteinuria should be excluded before performing a kidney biopsy in patients with nephrotic-range proteinuria and normal serum albumin."

States the diagnostic sequencing point that motivates this case definition.

👪

Inheritance

1

X-linked recessive inheritance HP:0001419

Both genetic forms are X-linked. The full phenotype is essentially confined to hemizygous males; heterozygous female carriers show attenuated features, most often low-molecular-weight proteinuria and, less consistently, hypercalciuria. De novo variants are not rare, accounting for roughly 12% of Dent disease 1 and up to 30% of Dent disease 2 cases.

X-linked recessive inheritance

Show evidence (5 references)

PMID:20946626 SUPPORT Other

"These features are generally found in males only, and may be present in early childhood, whereas female carriers may show a milder phenotype."

States the X-linked sex-limited expression pattern with attenuated carrier phenotype.

PMID:20946626 SUPPORT Other

"For example, the milder features of LMW proteinuria and hypercalciuria are found in approximately 70% and 50% of females carriers, respectively, whilst the more severe manifestations of nephrolithiasis have been reported in only 10 females and end-stage renal failure has been reported in only 1..."

Quantifies the attenuated carrier-female phenotype that the X-linked recessive designation predicts.

PMID:39794284 SUPPORT Other

"De novo variants account for ∼12% of DD1 cases"

Records the de novo variant fraction, which bears directly on recurrence counselling in an X-linked disorder.

+ 2 more references

◆

Subtypes

2

Dent disease 1 (CLCN5-related) MONDO:0010225

CLCN5 hgnc:2023 {'name': 'X-linked recessive inheritance'}

The commonest form, accounting for roughly half to two-thirds of patients. Inactivating CLCN5 variants remove or disable the electrogenic 2Cl-/H+ exchanger ClC-5 from the early endosomes of the proximal tubular subapical compartment. The renal phenotype is therefore a pure proximal tubulopathy with no obligate extrarenal features, although rickets, osteomalacia, and growth retardation occur secondary to the tubular losses.

Show evidence (2 references)

PMID:39794284 SUPPORT Other

"DD1 (MIM #300 009) is caused by inactivating variants in the CLCN5 gene (located on Xp11.22), which encodes the electrogenic 2Cl−/H+ exchanger ClC-5"

Defines Dent disease 1 as the CLCN5-related form and names the affected transporter and locus.

PMID:20946626 SUPPORT Other

"Thus, there is genetic heterogeneity for Dent's disease, with approximately 50-60% of patients having CLCN5 mutations (Dent disease 1), ~15% harbouring OCRL1 mutations (Dent disease 2) and the remaining 25-35% of patients having neither CLCN5 nor OCRL1 mutations but possibly defects in other genes."

Quantifies the share of patients attributable to CLCN5 and so the relative weight of this subtype.

Dent disease 2 (OCRL-related) MONDO:0010359

OCRL hgnc:8108 {'name': 'X-linked recessive inheritance'}

Roughly 15% of patients carry OCRL variants instead. The proximal tubular phenotype largely overlaps Dent disease 1, but mild extrarenal features may be present: raised muscle enzymes, mild developmental delay, short stature, and occasionally punctate cataract. The same gene causes Lowe syndrome, which dismech curates as a separate, more severe multisystem entry (Lowe_Syndrome); DD2 is modelled here as a subtype of Dent disease rather than duplicated there, matching the split that entry records. In the largest DD2 series 39% of patients had at least one extrarenal sign, with muscle findings much commoner than ocular ones, and the authors concluded DD2 is clinically distinct from Lowe syndrome rather than simply a mild version of it.

Show evidence (4 references)

PMID:39794284 SUPPORT Other

"Extrarenal manifestations of patients with DD2 are very mild compared with full-blown Lowe syndrome and may include punctuated congenital cataract, mild developmental delay, and short stature"

Defines the DD2 extrarenal profile and contrasts it with Lowe syndrome, which is the basis for keeping the two entries separate.

PMID:39794284 SUPPORT Other

"The manifestations of proximal tubular dysfunction overlap in patients with DD1 and DD2"

Justifies curating DD2 as a subtype of the same disease rather than a separate entry, since the renal mechanism and phenotype are shared.

PMID:34680992 SUPPORT Human Clinical

"The frequency of patients with at least one ES was 39%. Muscle findings are the most common ES (52%), while ocular findings are less common (11%)."

Largest DD2 cohort quantifies how often extrarenal signs occur and which organ systems dominate.

+ 1 more reference

?

Discussions and Knowledge Gaps

4

Is defective endosomal acidification, or luminal chloride accumulation, the step through which ClC-5 loss causes proximal tubular endocytic failure?

OPEN QUESTION OPEN acidification_vs_chloride

Attached to

pathophysiology#Defective Endosomal Acidification pathophysiology#Megalin and Cubilin Trafficking Failure

The textbook account is that ClC-5 supplies the countercurrent for the V-ATPase, so its loss impairs acidification and the ligand-receptor complex fails to dissociate. A knock-in mouse converting the exchanger into an uncoupled chloride channel breaks that account: its endosomes acidify normally, and it still shows the full renal phenotype and impaired proximal tubular endocytosis. Either luminal chloride concentration matters in its own right, or acidification is one of several parallel requirements. The question is not decorative: it determines whether a therapeutic strategy aimed at restoring endosomal pH could work at all.

Show evidence (1 reference)

PMID:20946626 SUPPORT Model Organism

"However, despite normal endosomal acidification, KI mice showed the same renal phenotype than KO mice and patients with Dent's disease, including LMW proteinuria, hyperphosphaturia and hypercalciuria."

The experimental result that makes the acidification-only account untenable.

What converts a proximal tubular endocytic defect into progressive chronic kidney disease, and why is the trajectory so variable within one family?

KNOWLEDGE GAP OPEN tubulopathy_to_ckd_transition

Attached to

pathophysiology#Tubulointerstitial Fibrosis and Progressive Nephron Loss phenotypes#Chronic kidney disease

The guideline states outright that the mechanism of this transition remains to be deciphered. Candidate routes are maladaptive proximal tubular responses driving inflammation and fibrosis, stress responses in distal nephron segments provoked by the tubular protein load, and a genuine podocyte component given that CLCN5 and OCRL appear to be expressed in podocytes. Because the same variant produces different outcomes within one family, whatever governs progression is not the genotype. This is the gap that matters most clinically, since kidney failure is what determines prognosis and nothing currently available is known to modify it.

Show evidence (2 references)

PMID:39794284 SUPPORT Other

"The mechanisms behind the transition from proximal tubular dysfunction to progressive chronic kidney disease (CKD) in DD remain to be deciphered."

The gap stated by the guideline itself.

PMID:39794284 SUPPORT Other

"Also, the course of kidney failure may be variable within the same family"

Establishes that the missing determinant is not the causal variant.

What causes Dent disease in the 25-35% of clinically typical patients with no identifiable CLCN5 or OCRL variant?

KNOWLEDGE GAP OPEN unexplained_third_of_patients

Attached to

genetic#Genetically unexplained Dent disease

A quarter to a third of patients meeting the clinical and biochemical definition have no variant in either known gene. No third locus has been confirmed in the fifteen years since the gap was first described. The residual group could reflect an unidentified gene acting on the same endocytic apparatus, non-coding or structural variation in CLCN5 or OCRL missed by standard sequencing, or phenocopies from a distinct mechanism. Until it is resolved, a negative gene panel cannot exclude the diagnosis.

Show evidence (2 references)

PMID:39794284 SUPPORT Other

"the remaining 25%–35% of patients having neither identifiable CLCN5 nor OCRL variants"

Quantifies the unexplained group in the most recent authoritative source.

PMID:20946626 SUPPORT Other

"A few patients with Dent's disease do not harbour mutations in CLCN5 and OCRL1, pointing to the involvement of other genes."

Shows the gap was already recognised in 2010 and remains open.

Can a mammalian model of Dent disease 2 be built, given that Ocrl knockout mice are essentially unaffected because of Inpp5b compensation?

HUMAN MODEL MISMATCH OPEN ocrl_mouse_model_mismatch

Attached to

pathophysiology#OCRL Phosphoinositide 5-Phosphatase Deficiency animal_models#Zebrafish

Mouse Ocrl loss does not reproduce the human renal phenotype, which is attributed to compensation by the paralog Inpp5b; the double knockout is embryonic lethal. The field therefore leans on zebrafish and on patient cells for Dent disease 2, and those models do not distinguish Dent disease 2 from Lowe syndrome, since both arise from ocrl loss and the human distinction depends on variant position and residual isoform expression. The mismatch is mechanistically meaningful rather than merely inconvenient: the human DD2/Lowe boundary is set by how much OCRL activity survives, which is exactly the variable a null allele removes.

Show evidence (2 references)

PMID:40778266 SUPPORT Model Organism

"Zebrafish has been used to study OCRL function in vivo and to successfully model these two rare genetic conditions."

Documents the reliance on a non-mammalian model for both OCRL phenotypes.

PMID:34586410 SUPPORT In Vitro

"Truncating mutations in OCRL exons 1-7 lead to Dent disease-2, whereas those in exons 8-24 lead to Lowe syndrome."

Shows the human distinction rests on residual isoform expression, which a null allele cannot model.

⚙

Pathophysiology

11

ClC-5 Chloride-Proton Exchanger Loss of Function

In Dent disease 1 an inactivating CLCN5 variant removes or disables ClC-5, the electrogenic 2Cl-/H+ exchanger of the early endosomes of the subapical compartment of proximal tubular cells. This is the initiating molecular lesion; the restriction of the clinical picture to a proximal tubulopathy follows from where the protein is normally expressed. Missense variants reach this state by several routes - endoplasmic reticulum retention and degradation, loss of transport function with normal localisation, or mislocalisation within the endosomal system.

kidney proximal convoluted tubule epithelial cell CL:1000838

CLCN5 hgnc:2023

Genetic context variant_origin: GERMLINE zygosity: HEMIZYGOUS functional_impact_category: LOSS_OF_FUNCTION

2Cl-/H+ exchange by ClC-5 GO:0062158 ↓ DECREASED

proximal tubular subapical early endosome GO:0005769

renal proximal tubule UBERON:0004134

Downstream

Defective Endosomal Acidification Loss of the endosomal chloride conductance removes the countercurrent that lets the V-ATPase acidify the vesicle lumen.

Megalin and Cubilin Trafficking Failure Independently of, and in addition to, the acidification defect, ClC-5 loss produces a severe trafficking defect that strips megalin and cubilin from the brush border. A Drosophila nephrocyte model plus confirmation in Clcn5 knockout mice adds a secretory-pathway component, with Cubilin retained in the endoplasmic reticulum and its partner Amnionless reduced.

Show evidence (2 references)

PMID:39794284 SUPPORT Other

"The clinical presentation of DD1 as a proximal tubulopathy reflects the predominant expression of ClC-5 in the early endosomes of the subapical compartment of proximal tubular cells"

Places the initiating lesion in the proximal tubular subapical endosome and explains why the phenotype is a proximal tubulopathy.

PMID:19019917 SUPPORT In Vitro

"It is generally thought that the principal cause of Dent's disease (31) results from a loss of functional CLC-5 from the subapical endosomes of kidney proximal tubule cells leading to a defect in endosomal acidification and impaired protein reabsorption"

States the consensus initiating mechanism and its immediate consequences, which are the downstream nodes here.

Defective Endosomal Acidification

Progression along the endocytic pathway requires the V-ATPase to acidify each vesicle to about pH 5.0, which is what dissociates ligand from receptor and permits receptor recycling. That proton pumping needs a parallel chloride conductance for electroneutrality, and ClC-5 supplies it. Losing ClC-5 leaves positive charge accumulating in the lumen and acidification impaired. This node is necessary but not sufficient for the disease phenotype: a knock-in mouse converting the exchanger into an uncoupled chloride channel acidifies its endosomes normally and still reproduces the full renal phenotype, so luminal chloride accumulation rather than pH alone appears to carry part of the mechanism.

endosomal lumen acidification GO:0048388 ↓ DECREASED

proximal tubular subapical early endosome GO:0005769

Downstream

Megalin and Cubilin Trafficking Failure Without the pH drop the ligand-receptor complex does not dissociate and the receptor is not returned to the apical membrane.

Show evidence (3 references)

PMID:20946626 SUPPORT Other

"Endosomal acidification (up to pH 5.0), that is necessary for dissociation of the ligand-receptor complex, recycling of receptors to the apical membrane, and progression of ligands into lysosomes, is achieved by ATP-driven transport of cytosolic H+ through the V-ATPase."

Establishes why endosomal pH matters for receptor recycling, which is the next node in the chain.

PMID:20946626 SUPPORT Model Organism

"Furthermore, in vitro experiments have shown a decreased acidification of early endosomes in ClC-5-deficient mice"

Demonstrates that the acidification defect is actually present in ClC-5-deficient tissue.

PMID:20946626 REFUTE Model Organism

"Furthermore, both the KI and KO mouse showed impaired PT endocytosis, indicating that PT dysfunction in Dent's disease may occur despite normal acidification of the endosomes."

Refutes the claim that failed acidification is the sole route to proximal tubular dysfunction, since the knock-in mouse acidifies normally and is still affected.

OCRL Phosphoinositide 5-Phosphatase Deficiency

In Dent disease 2 the initiating lesion is instead a reduction in OCRL activity. OCRL is a phosphatidylinositol 4,5-bisphosphate 5-phosphatase that sits on early endosomes and keeps PI(4,5)P2 low there. Variants in exons 1-7 permit expression of a shortened isoform from an internal start codon, which is why the resulting phenotype is Dent disease rather than the multisystem Lowe syndrome.

OCRL hgnc:8108

Genetic context variant_origin: GERMLINE zygosity: HEMIZYGOUS functional_impact_category: PARTIAL_LOSS_OF_FUNCTION

phosphatidylinositol dephosphorylation GO:0046856 ↓ DECREASED

early endosome GO:0005769

Downstream

Endosomal PI(4,5)P2 Accumulation and Actin Dysregulation

Show evidence (1 reference)

PMID:39794284 SUPPORT Other

"OCRL encodes the PI(4,5)P2 5-phosphatase OCRL, which controls phosphatidylinositol moieties in the endolysosomal pathway by degrading PI(4,5)P2"

Names the enzymatic activity lost in Dent disease 2 and the compartment where it acts.

Endosomal PI(4,5)P2 Accumulation and Actin Dysregulation

Reduced OCRL activity lets PI(4,5)P2 build up on early endosomal membranes. The excess lipid drives uncontrolled actin polymerisation into basket-like structures around the aberrant organelles, which physically obstructs receptor trafficking. This is the Dent disease 2 route into the same endocytic failure that ClC-5 loss produces in Dent disease 1.

kidney proximal convoluted tubule epithelial cell CL:1000838

actin filament organization GO:0007015 ↕ DYSREGULATED

early endosome GO:0005769

Animal models

OCRL-deficient zebrafish Zebrafish partially recapitulates The renal tubular arm of the model reproduces the endocytic and lysosomal consequences of OCRL loss.

Downstream

Megalin and Cubilin Trafficking Failure

Show evidence (2 references)

PMID:39794284 SUPPORT Other

"The increase in PI(4,5)P2 levels in early endosomes stimulates uncontrolled actin polymerization into ‘basket’ structures surrounding aberrant organelles, impairing the trafficking of different receptors, including megalin needed for receptor-mediated endocytosis"

Traces the OCRL lesion through PI(4,5)P2 accumulation and actin disorganisation to impaired megalin trafficking.

PMID:39794284 SUPPORT Other

"The fact that variants in OCRL generally mimic the proximal tubular dysfunction encountered in DD1 is explained by the association of the OCRL protein with early endosomes, where it acts to maintain low levels of phosphatidylinositol (PI) 4,5-bisphosphate (PI(4,5)P2) for proper endocytic trafficking"

States explicitly that the DD1 and DD2 lesions converge on the same endosomal trafficking step, which is the structure of this pathograph.

Megalin and Cubilin Trafficking Failure

The convergence point of both genetic forms. Megalin and cubilin are the multiligand receptors of the apical brush border that perform receptor-mediated endocytosis in the proximal tubule. Whichever lesion is upstream, they are lost or reduced at the brush border and their cargo is no longer retrieved from the filtrate. A Drosophila nephrocyte model of Dent disease 1, confirmed in ClC-5 knockout mice, adds an earlier secretory-pathway step, with Cubilin accumulating in the endoplasmic reticulum and Amnionless reduced overall, so the receptor complex may never reach the surface rather than only failing to recycle.

kidney proximal convoluted tubule epithelial cell CL:1000838

receptor-mediated endocytosis GO:0006898 ↓ DECREASED endocytic recycling GO:0032456 ↓ DECREASED

renal proximal tubule UBERON:0004134

Animal models

Clcn5 knockout mouse Mouse recapitulates Reproduces the endocytic failure of the proximal tubule, both receptor-mediated and fluid-phase, with slowed internalization of apical transporters.

Drosophila nephrocyte ClC-c depletion model Fruit fly recapitulates Reproduces receptor loss from the cell surface and identifies an earlier endoplasmic-reticulum export step in the mechanism.

Downstream

Failure of Proximal Tubular Protein Reabsorption

Urinary Loss of Vitamin D-Binding Protein and Parathyroid Hormone The megalin/cubilin complex is also what retrieves vitamin D-binding protein, 25(OH)-vitamin D3, and filtered PTH, so its loss diverts those ligands into the urine.

Generalized Proximal Tubular Solute Wasting

Show evidence (4 references)

PMID:20946626 SUPPORT Other

"These vesicles belong to the receptor-mediated endocytic pathway, which involves the multiligand receptors, megalin and cubilin, located at the apical brush border of PT cells"

Identifies the receptor system whose failure is the node.

PMID:11099045 SUPPORT Model Organism

"Here we show that disruption of the mouse clcn5 gene causes proteinuria by strongly reducing apical proximal tubular endocytosis."

Original knockout mouse demonstrating that the endocytic failure is what produces the proteinuria.

PMID:41690574 SUPPORT Model Organism

"Upon depletion of ClC-c, the fly ortholog of CLCN5, Cubilin was lost from the plasma membrane of nephrocytes, leading to a strong decrease in albumin uptake and ectopic slit diaphragms. Importantly, Cubilin exhibited a strong accumulation in the endoplasmic reticulum, while its binding partner..."

Adds a secretory-pathway component to the trafficking failure and shows the receptor is lost from the plasma membrane.

+ 1 more reference

Failure of Proximal Tubular Protein Reabsorption

Filtered low-molecular-weight proteins - beta-2-microglobulin, alpha-1-microglobulin, retinol-binding protein, and the vitamin-carrier proteins - are normally reclaimed almost completely by proximal tubular endocytosis. When that fails they appear in the urine. This is the obligate finding of the disease and, because the load can be large, total urinary protein may reach the nephrotic range without any glomerular lesion or hypoalbuminaemia.

kidney proximal convoluted tubule epithelial cell CL:1000838

protein transport GO:0015031 ↓ DECREASED

renal proximal tubule UBERON:0004134

Downstream

Low-molecular-weight proteinuria

Tubulointerstitial Fibrosis and Progressive Nephron Loss The tubular protein load is the proximate injury, but the cited source says explicitly that the transition from proximal tubular dysfunction to progressive chronic kidney disease "remain[s] to be deciphered", so the intermediates are left unstated rather than inferred.

Focal segmental glomerulosclerosis Glomerular lesions are found on most Dent disease biopsies. Whether they arise from the tubular protein load, from podocyte expression of ClC-5 and OCRL, or from both is unsettled.

Show evidence (2 references)

PMID:39794284 SUPPORT Other

"As low-molecular-weight proteins are reabsorbed by receptor-mediated endocytosis in proximal tubular cells, low-molecular-weight proteinuria is an obligate finding in DD."

Directly links the endocytic failure to the obligate clinical finding.

PMID:39794284 SUPPORT Other

"Affected individuals may present nephrotic-range proteinuria which may be misinterpreted and cause diagnostic delay."

Records the diagnostic consequence of a tubular protein load large enough to look glomerular.

Urinary Loss of Vitamin D-Binding Protein and Parathyroid Hormone

Losing megalin/cubilin-mediated retrieval sends filtered vitamin D-binding protein, 25(OH)-vitamin D3 and PTH into the urine. Two opposing effects follow. Reduced endocytosis of luminal PTH raises the concentration seen by apical PTH receptors, which should drive 1-alpha-hydroxylation of 25(OH)-vitamin D3 to the active hormone and so increase intestinal calcium absorption; at the same time the precursor itself is being lost in the urine. The balance of those two effects is the current explanation for why serum 1,25(OH)2-vitamin D3 is variable between patients and for why hypercalciuria is present in most but not all of them. The mechanism is inferred from the mouse model and from the known cargo of the receptor complex rather than demonstrated directly in patients.

kidney proximal convoluted tubule epithelial cell CL:1000838

renal excretion of vitamin D metabolites and PTH GO:0007588 ↕ DYSREGULATED

Animal models

Clcn5 knockout mouse Mouse recapitulates The model is the origin of the two-opposing-effects account of hypercalciuria in this disease.

Downstream

Urinary Calcium Supersaturation

Hypercalciuria

Show evidence (1 reference)

PMID:11099045 SUPPORT Model Organism

"This may be caused by an increased stimulation of luminal parathyroid hormone (PTH) receptors owing to the observed decreased tubular endocytosis of PTH. The rise in luminal PTH concentration should also stimulate the hydroxylation of 25(OH) vitamin D3 to the active hormone. However, this is..."

Sets out the two opposing vitamin D effects that this node represents, as observed in the Clcn5 knockout mouse.

Generalized Proximal Tubular Solute Wasting

Beyond protein, the proximal tubule of a Dent disease patient leaks a variable combination of amino acids, phosphate, glucose, urate and potassium, and urinary acidification may be impaired. The picture is an incomplete Fanconi syndrome rather than the full generalised defect: the guideline records it in 25-65% of Dent disease 1 and 30-70% of Dent disease 2 patients. Sustained phosphate wasting is what produces the bone disease.

kidney proximal convoluted tubule epithelial cell CL:1000838

phosphate ion transport GO:0006817 ↓ DECREASED renal solute excretion GO:0007588 ↕ DYSREGULATED

renal proximal tubule UBERON:0004134

Downstream

Hypophosphatemia

Aminoaciduria

Glycosuria

Hypokalemia

Rickets

Show evidence (1 reference)

PMID:20946626 SUPPORT Other

"Dent's disease may also be associated with aminoaciduria, phosphaturia, glycosuria, uricosuria, kaliuresis, and impaired urinary acidification, and is often complicated by rickets or osteomalacia"

Enumerates the solutes wasted at this node and names the bone consequence of the phosphate leak.

Urinary Calcium Supersaturation

Hypercalciuria raises the relative supersaturation of the urine with respect to calcium oxalate and calcium phosphate, which is the thermodynamic driving force for stone formation. In Dent disease the lithogenic solute is calcium; citrate excretion is lower than in other forms of renal Fanconi syndrome, removing some of the usual inhibitory capacity. This node is the disease-specific substitution into the nephrolithiasis module's supersaturation trigger.

renal calcium excretion GO:0007588 ↕ DYSREGULATED calcium ion transport GO:0006816 ↕ DYSREGULATED

Downstream

Calcium Crystal Nucleation and Retention

Show evidence (3 references)

PMID:12444212 SUPPORT Human Clinical

"Hypercalciuria is the major risk factor promoting stone formation in Dent's disease, also known as X-linked recessive nephrolithiasis, but the effects of diuretics on calcium excretion and other stone risk factors in this disease are unknown."

Identifies calcium as the lithogenic solute of this disease, which is the substitution the module expects.

PMID:12444212 SUPPORT Human Clinical

"In patients with Dent's disease during chlorthalidone therapy, the supersaturation ratios for calcium oxalate and calcium phosphate fell by 25% and 35%, respectively."

Measures calcium oxalate and calcium phosphate supersaturation directly in Dent disease patients, grounding this node in human data.

PMID:39794284 SUPPORT Other

"citrate excretion in DD is lower compared with other forms of renal Fanconi syndrome"

Records the reduced inhibitory capacity that accompanies the raised calcium load in this disease.

Calcium Crystal Nucleation and Retention

Supersaturated urine nucleates calcium crystals which must then be retained rather than flushed out for nephrocalcinosis or a stone to form. In Dent disease retention appears to carry independent weight, because nephrolithiasis and nephrocalcinosis have been reported in patients without hypercalciuria, which has been attributed to impaired clearance of microcrystals from the collecting duct epithelial surface. Nephrocalcinosis is typically detectable from childhood while discrete stones appear later.

renal tubular epithelial cell CL:0002518

crystal-epithelial cell adhesion GO:0007155

kidney UBERON:0002113

Downstream

Nephrocalcinosis

Nephrolithiasis

Show evidence (2 references)

PMID:39794284 SUPPORT Other

"which might be explained by impaired clearance of microcrystals from the surface of collecting duct cells, as demonstrated in vitro"

Supports treating crystal retention as a step with its own weight in this disease rather than a passive consequence of supersaturation.

PMID:39794284 SUPPORT Other

"Nephrocalcinosis is often detectable from childhood while kidney stones manifest at a later age"

Gives the temporal ordering of the two mineral outcomes downstream of this node.

Tubulointerstitial Fibrosis and Progressive Nephron Loss

How a proximal tubulopathy becomes progressive chronic kidney disease is the least resolved part of the mechanism and the guideline says so plainly. The proposed route is that early adaptive changes in proximal tubular cells - proliferation, dedifferentiation, autophagy, metabolic adaptation - become maladaptive, promoting inflammation and tubulointerstitial fibrosis, with the tubular protein load itself contributing by stressing distal nephron segments. Biopsy series show focal interstitial fibrosis, interstitial lymphocytic infiltration and tubular damage alongside the glomerular lesions, and a knock-in mouse carrying a representative pathogenic Clcn5 missense variant develops fibrosis and apoptosis with age.

kidney proximal convoluted tubule epithelial cell CL:1000838

extracellular matrix organization GO:0030198 ↕ DYSREGULATED inflammatory response GO:0006954 ↑ INCREASED

kidney UBERON:0002113

Animal models

Clcn5 knock-in missense mouse Mouse recapitulates With ageing the model accumulates renal fibrosis and apoptosis alongside metabolic change, which is the transition from tubulopathy to CKD.

Downstream

Chronic kidney disease

Show evidence (4 references)

PMID:39794284 SUPPORT Other

"The mechanisms behind the transition from proximal tubular dysfunction to progressive chronic kidney disease (CKD) in DD remain to be deciphered."

Records explicitly that this step of the causal chain is unresolved, which the node description must not overstate.

PMID:39794284 SUPPORT Other

"Early changes in proximal tubular cells, including proliferation, dedifferentiation, autophagy, and metabolic adaptation, may become maladaptive and promote inflammation and progression of tubulointerstitial fibrosis by various mechanisms"

States the proposed, explicitly hypothetical route from tubular injury to fibrosis.

PMID:27697782 SUPPORT Human Clinical

"focal interstitial fibrosis in 60% (18 of 30), interstitial lymphocytic infiltration in 53% (16 of 30), and tubular damage in 70% (21 of 30)"

Human biopsy series quantifying the interstitial and tubular lesions this node describes.

+ 1 more reference

⬡

Pathograph

Use the checkboxes to hide or show graph categories. Hover nodes for evidence and cross-linked metadata.

●

Phenotypes

17

Eye 1

Cataract OCCASIONAL Punctate cataract HP:0007648

Show evidence (3 references)

PMID:39794284 SUPPORT Other

"Congenital cataract | Very rare | 7–10"

Guideline frequency table shows cataract is rare in Dent disease 1 and uncommon even in Dent disease 2.

PMID:20946626 SUPPORT Other

"although it is important to note that none of these had the severe cataracts or intellectual deficit that is typically found in patients with Lowe syndrome"

Contrasts the ocular phenotype with Lowe syndrome, supporting the separation of the two entries.

PMID:22876375 SUPPORT REVIEW SYNTHESIS Other

"Males with Dent disease 2 (caused by pathogenic variants in OCRL) may also have mild intellectual disability, cataracts, and/or elevated muscle enzymes."

GeneReviews restricts cataract to the Dent disease 2 subtype, which is what the DD2 subtype scoping on this phenotype records.

Genitourinary 9

Low-molecular-weight proteinuria OBLIGATE HP:0003126

Show evidence (3 references)

PMID:39794284 SUPPORT Other

"Low-molecular-weight proteinuria | 100 | 100"

Guideline frequency table records low-molecular-weight proteinuria in 100% of both Dent disease 1 and Dent disease 2 patients.

PMID:20946626 SUPPORT Other

"Low-molecular-weight (LMW) proteinuria represents the most consistent manifestation of Dent's disease, detected in almost all affected males and obligate female carriers."

Independent review confirms this is the most consistent finding and extends it to obligate carriers.

PMID:39794284 SUPPORT Other

"An α1-microglobulin/creatinine ratio above 120 mg/g (13.6 mg/mmol) has high accuracy in separating DD from glomerular disease"

Gives the quantitative threshold that makes this phenotype diagnostically decisive.

Hypercalciuria FREQUENT HP:0002150

Show evidence (3 references)

PMID:39794284 SUPPORT Other

"Hypercalciuria | 44–90 | 80–100"

Guideline frequency table gives the reported ranges for Dent disease 1 and Dent disease 2.

PMID:39794284 SUPPORT Other

"While proteinuria is present during the entire course of the disease, hypercalciuria is detected in 61%–73% of children and young adults compared with 14%–19% of adults"

Documents the age dependence that makes hypercalciuria an unreliable adult diagnostic criterion.

PMID:39794284 SUPPORT Other

"Although hypercalciuria is the second most frequent finding in DD, its absence does not exclude a diagnosis of DD."

States that this phenotype, while characteristic, is not obligate.

Nephrocalcinosis FREQUENT HP:0000121

Show evidence (1 reference)

PMID:39794284 SUPPORT Other

"Nephrocalcinosis | 40–75 | 10–40"

Guideline frequency table quantifies nephrocalcinosis separately for the two genetic subtypes.

Nephrolithiasis FREQUENT HP:0000787

Show evidence (2 references)

PMID:39794284 SUPPORT Other

"Nephrolithiasis | 20–40 | 10–15"

Guideline frequency table quantifies stone disease in both genetic subtypes.

PMID:20946626 SUPPORT Other

"Dent's disease is a renal tubular disorder characterized by manifestations of proximal tubule dysfunction, including low-molecular-weight proteinuria, hypercalciuria, nephrolithiasis, nephrocalcinosis, and progressive renal failure."

Establishes nephrolithiasis as a defining manifestation of the disorder.

Chronic kidney disease FREQUENT HP:0012622

Course: PROGRESSIVE

Show evidence (4 references)

PMID:39794284 SUPPORT Other

"Dent disease is a rare X-linked tubulopathy that is characterized by low-molecular-weight proteinuria associated with hypercalciuria, which may lead to nephrolithiasis, nephrocalcinosis, and kidney failure between the third and fifth decades of life in 30%-80% of affected males."

Gives the timing and the proportion of affected males reaching kidney failure.

PMID:39794284 SUPPORT Other

"Four out of ten patients aged 30–40 years, three out of nine aged 40–50 years, and three out of four aged 50–60 years had kidney failure"

Provides the age-stratified counts behind the aggregate kidney-failure figure.

PMID:39794284 SUPPORT Other

"Also, the course of kidney failure may be variable within the same family"

Records intrafamilial variability, which constrains how far prognosis can be individualised from genotype.

+ 1 more reference

Focal segmental glomerulosclerosis FREQUENT HP:0000097

Show evidence (3 references)

PMID:27697782 SUPPORT Human Clinical

"Prominent histologic findings included focal global glomerulosclerosis in 83% (25 of 30; affecting 16%±19% glomeruli), mild segmental foot process effacement in 57% (13 of 23)"

International biopsy series quantifying the glomerular lesion in Dent disease.

PMID:27697782 SUPPORT Human Clinical

"Higher percentages of globally sclerotic glomeruli, foot process effacement, and interstitial inflammation were associated with lower eGFR at biopsy, whereas foot process effacement was associated with steeper annual eGFR decline."

Links the glomerular lesion to kidney function and rate of decline, supporting its prognostic weight.

PMID:27697782 SUPPORT Human Clinical

"Dent disease should be suspected in boys and men who have unexplained proteinuria with focal global glomerulosclerosis and segmental foot process effacement on renal biopsy."

States the diagnostic inversion this phenotype creates, which is the practical reason to curate it.

Aminoaciduria FREQUENT HP:0003355

Show evidence (1 reference)

PMID:39794284 SUPPORT Other

"Aminoaciduria | 20–50 | 40–70"

Guideline frequency table quantifies aminoaciduria in both genetic subtypes.

Glycosuria OCCASIONAL HP:0003076

Show evidence (1 reference)

PMID:39794284 SUPPORT Other

"Glucosuria | 20–40 | 5–15"

Guideline frequency table quantifies glycosuria in both genetic subtypes.

Hematuria OCCASIONAL HP:0000790

Show evidence (2 references)

PMID:20946626 SUPPORT Other

"In addition, these patients may also have nephrocalcinosis, nephrolithiasis, haematuria, hypophosphataemia and/or renal insufficiency."

Lists haematuria among the manifestations of Dent disease.

PMID:34680992 SUPPORT Human Clinical

"Nephrocalcinosis was identified in 42% of the patients, nephrolithiasis in 32%, and hematuria in 59%."

Quantifies haematuria in the largest Dent disease 2 cohort.

Metabolism 3

Hypophosphatemia OCCASIONAL HP:0002148

Show evidence (2 references)

PMID:39794284 SUPPORT Other

"Hypophosphatemia | 15–35 | 10–20"

Guideline frequency table quantifies hypophosphatemia in both genetic subtypes.

PMID:39794284 SUPPORT Other

"As hypophosphataemia in DD is usually mild or moderate, it can be corrected with increased dietary phosphate and/or oral supplementation."

Characterises the severity of the phosphate deficit and its management.

Hypokalemia OCCASIONAL HP:0002900

Show evidence (1 reference)

PMID:39794284 SUPPORT Other

"Hypokalaemia | 20–40 | 10–20"

Guideline frequency table quantifies hypokalaemia in both genetic subtypes.

Elevated circulating creatine kinase concentration VERY_FREQUENT Elevated circulating creatine kinase activity HP:0003236

Show evidence (2 references)

PMID:39794284 SUPPORT Other

"Elevated serum levels of CPK, ASAT and/or LDH | 5–20 | 80–90"

Guideline frequency table gives the strong subtype discrimination for raised muscle enzymes.

PMID:34680992 SUPPORT Human Clinical

"Muscle findings are the most common ES (52%), while ocular findings are less common (11%)."

Largest Dent disease 2 cohort confirms muscle involvement as the dominant extrarenal finding.

Musculoskeletal 2

Rickets OCCASIONAL HP:0002748

Show evidence (2 references)

PMID:39794284 SUPPORT Other

"Rickets | 5–33 | 10–20"

Guideline frequency table quantifies rickets in both genetic subtypes.

PMID:39794284 SUPPORT Other

"Few data on bone health in DD have been reported, except that some patients present with vitamin D-resistant rickets"

Characterises the rickets as vitamin D-resistant, which drives the treatment caution recorded here.

Osteomalacia OCCASIONAL HP:0002749

Show evidence (1 reference)

PMID:39794284 SUPPORT Other

"Prolonged hypophosphataemia may cause bone demineralization manifesting as rickets in children or osteomalacia in adults."

Establishes osteomalacia as the adult skeletal manifestation of the tubular phosphate leak.

Nervous System 1

Intellectual disability OCCASIONAL HP:0001249

Severity: MILD

Show evidence (2 references)

PMID:39794284 SUPPORT Other

"Intellectual impairment | 0–9 | 25–30"

Guideline frequency table separates intellectual impairment between the two genetic subtypes.

PMID:20946626 SUPPORT Other

"Moreover, the patients with Dent disease 2 and mild intellectual deficit were adults, who had not, over time, developed more overt features of Lowe's syndrome"

Establishes that the intellectual phenotype stays mild and does not evolve into Lowe syndrome, which underpins the lump/split decision.

Growth 1

Growth delay FREQUENT HP:0001510

Show evidence (1 reference)

PMID:39794284 SUPPORT Other

"Growth retardation | 10–20 | 60–80"

Guideline frequency table shows the marked excess of growth retardation in Dent disease 2.

🧬

Genetic Associations

3

CLCN5 (Loss-of-function)

Gene: CLCN5 hgnc:2023 relationship_type: CAUSATIVE variant_origin: GERMLINE

Show evidence (5 references)

PMID:39794284 SUPPORT Other

"To date, more than 300 distinct disease-causing variants in the CLCN5 gene have been identified."

Establishes the breadth of the CLCN5 allelic spectrum underlying Dent disease 1.

PMID:39794284 SUPPORT Other

"There are no clear mutation hotspots as only a small number of recurrent variants has been reported in different geographic areas"

Records that CLCN5 variants are largely private, which bears on diagnostic sequencing strategy.

PMID:39794284 REFUTE Other

"Blanchard et al. found no difference in age at diagnosis, estimated glomerular filtration rate (eGFR), proteinuria, or hypercalciuria, indicating that there is no correlation between genotype and phenotype in DD1"

Refutes a simple genotype-severity correlation in Dent disease 1, which is why variant class is not used here to stratify prognosis.

+ 2 more references

OCRL (Loss-of-function)

Gene: OCRL hgnc:8108 relationship_type: CAUSATIVE variant_origin: GERMLINE

Show evidence (3 references)

PMID:39794284 SUPPORT Other

"Regarding the OCRL gene, a genotype–phenotype correlation is hypothesized because nearly all truncating variants associated with DD2 are located in exons 1–7, which encompass the PH domain, while variants associated with Lowe syndrome are located in exons 8–24"

Gives the exon-position rule that separates Dent disease 2 from Lowe syndrome within one gene.

PMID:39794284 REFUTE Other

"Of note, both a Lowe syndrome and DD2 phenotype have been reported for five OCRL variants, arguing against a clear genotype–phenotype effect"

Refutes a strict exon-position rule, so the DD2/Lowe boundary is not fully predictable from genotype.

PMID:34586410 SUPPORT In Vitro

"We successfully cloned the novel isoform transcripts from OCRL exons 6-24, including the translation-initiation codons present in exon 8."

Provides the molecular basis for the exon-position rule, since an internal start codon in exon 8 permits partial OCRL expression in Dent disease 2.

Genetically unexplained Dent disease

relationship_type: UNKNOWN

Show evidence (2 references)

PMID:39794284 SUPPORT Other

"the remaining 25%–35% of patients having neither identifiable CLCN5 nor OCRL variants"

Quantifies the genetically unexplained fraction of clinically typical Dent disease.

PMID:20946626 SUPPORT Other

"A few patients with Dent's disease do not harbour mutations in CLCN5 and OCRL1, pointing to the involvement of other genes."

Independent review confirms an unexplained residue and that no additional locus has been established.

💊

Medical Actions

9

Potassium Citrate

Action: Pharmacotherapy NCIT:C15986

Agent: potassium citrate NCIT:C29372

Platform: Small molecule

Alkalinising citrate is the treatment the 2025 ERA/ESPN recommendations place first for stone and nephrocalcinosis risk, on a weak recommendation grade because no human trial in Dent disease exists. The case rests on a high-citrate diet slowing CKD in Clcn5 knockout mice, on citrate's proven benefit in idiopathic hypercalciuria with hypocitraturia, and on citrate excretion in Dent disease being lower than in other Fanconi syndromes. Urinary pH needs monitoring, since over-alkalinisation risks calcium phosphate precipitation.

Mechanism Target:

INHIBITS Urinary Calcium Supersaturation — Citrate chelates urinary calcium and raises urinary pH, lowering the relative supersaturation that drives calcium crystal nucleation.

Show evidence (1 reference)

PMID:39794284 SUPPORT Other

"Potassium citrate reduces recurrent calcium oxalate nephrolithiasis in patients with idiopathic hypercalciuria and hypocitraturia"

The mechanistic rationale is imported from idiopathic hypercalciuria, where the supersaturation effect is established.

INHIBITS Tubulointerstitial Fibrosis and Progressive Nephron Loss — In the knockout mouse a high-citrate diet preserved GFR and reduced tubular atrophy, interstitial fibrosis and nephrocalcinosis. No human equivalent has been done.

Show evidence (1 reference)

PMID:16014041 SUPPORT Model Organism

"ClC-5 knockout mice fed a zero citrate diet had significantly increased tubular atrophy, interstitial fibrosis, cystic changes, and nephrocalcinosis compared to ClC-5 knockout mice fed a high citrate diet."

Directly measures the fibrosis endpoint this link claims, in the disease's own animal model.

Show evidence (3 references)

PMID:39794284 SUPPORT Other

"We suggest that citrate treatment may be considered in patients with DD, in particular in the presence of nephrocalcinosis/stone disease (Grade C, weak)."

The guideline recommendation itself, with its grade, which is the weakest form of endorsement it issues.

PMID:39794284 NO_EVIDENCE Other

"There have been no human trials studying the efficacy of citrate supplementation in DD."

Records that no human efficacy data exist for this treatment in this disease, which is why the grade is weak.

PMID:16014041 SUPPORT Model Organism

"High citrate diet preserved renal function and delayed progression of renal disease in ClC-5 knockout mice even in the apparent absence of stone formation."

The principal preclinical result behind the recommendation, and the source of its rationale.

Thiazide Diuretics

Action: Pharmacotherapy NCIT:C15986

Agent: thiazide diuretic NCIT:C49185 hydrochlorothiazide CHEBI:5778 chlorthalidone CHEBI:3654

Platform: Small molecule

Thiazides reliably lower urinary calcium in Dent disease - chlorthalidone normalised calcium excretion in seven of eight patients in a randomised crossover study, and hydrochlorothiazide cut spot urinary calcium by 42% in an open-label trial - yet the 2025 guideline recommends against systematic use. The reason is the toxicity, not a failure of effect: hypovolaemia, hypokalaemia and hyponatraemia appeared in the same trials, no long-term kidney or stone outcome data exist in this disease, and Dent disease 2 patients are especially prone to dehydration and acute kidney injury on thiazides.

Mechanism Target:

INHIBITS Urinary Calcium Supersaturation — Thiazides act at the distal convoluted tubule, which is unaffected by the ClC-5 lesion, so the hypocalciuric response is intact in Dent disease.

Show evidence (1 reference)

PMID:12444212 SUPPORT Human Clinical

"The intact hypocalciuric response to a thiazide diuretic indicates that inactivation of the ClC-5 chloride channel does not impair calcium transport in the distal convoluted tubule and indicates that thiazides should be useful in reducing the risk of kidney stone recurrence in patients with..."

Establishes both that the drug target is intact in this disease and that supersaturation falls in response.

Show evidence (6 references)

PMID:12444212 SUPPORT Human Clinical

"With chlorthalidone, calcium excretion fell to normal (<4.0 mg/kg per d) in all but one patient in each group."

Randomised crossover data quantifying the hypocalciuric effect in genetically confirmed Dent disease.

PMID:18976849 SUPPORT Human Clinical

"The greatest HCTZ doses decreased spot urinary calcium excretion by 42% compared with baseline"

Independent open-label trial confirming a dose-dependent fall in urinary calcium.

PMID:18976849 REFUTE Human Clinical

"However, patients developed adverse reactions, including muscle cramps (n = 2), biological (n = 7) or symptomatic hypovolemia (n = 1), hypokalemia (n = 4), and hyponatremia (n = 1), which all corrected after treatment withdrawal."

Refutes routine use by documenting that every patient in the trial developed a volume or electrolyte adverse effect.

+ 3 more references

Phosphate Supplementation for Rickets and Osteomalacia

Action: Pharmacotherapy NCIT:C15986

Agent: phosphate CHEBI:26020

Platform: Small molecule

Oral phosphate salts, titrated on serum alkaline phosphatase and on radiographic improvement, for patients with hypophosphataemia and signs of rickets or osteomalacia. Crucially, active vitamin D must not be added in the way it would be for X-linked hypophosphataemic rickets, because 1,25(OH)2 vitamin D is already inherently elevated in Dent disease and raising it further worsens the hypercalciuria.

Mechanism Target:

RESTORES Hypophosphatemia — Replaces the phosphate lost through the proximal tubule, correcting the substrate deficit that drives bone demineralization.

Show evidence (1 reference)

PMID:39794284 SUPPORT Other

"As hypophosphataemia in DD is usually mild or moderate, it can be corrected with increased dietary phosphate and/or oral supplementation."

States that supplementation corrects the deficit this link targets.

Show evidence (2 references)

PMID:39794284 SUPPORT Other

"We suggest treating patients with DD using phosphate salts in case of hypophosphatemia and signs of rickets of osteomalacia (Grade X, weak)."

The guideline recommendation for this treatment, with its grade.

PMID:39794284 REFUTE Other

"In contrast to hypophosphataemic rickets, active vitamin D should not be given because of inherently elevated 1.25(OH)2 vitamin D and potential worsening of hypercalciuria."

Refutes the transfer of the standard hypophosphataemic-rickets regimen into this disease, which is the key prescribing trap.

Vitamin A Supplementation

Action: Pharmacotherapy NCIT:C15986

Agent: vitamin A CHEBI:12777

Platform: Small molecule

Retinol-binding protein is one of the low-molecular-weight proteins lost in the urine, so vitamin A deficiency is a foreseeable consequence of the endocytic defect. The guideline asks for vigilance for ocular symptoms, retinol measurement if they appear, and supplementation if low.

Mechanism Target:

BYPASSES Failure of Proximal Tubular Protein Reabsorption — Supplementation does not repair the endocytic defect; it replaces the vitamin whose carrier protein is being lost through it.

Show evidence (1 reference)

PMID:39794284 SUPPORT Other

"Retinol-binding protein is lost as part of low-molecular-weight proteinuria."

Names the mechanism by which the vitamin is depleted, which is what the supplement works around.

Show evidence (1 reference)

PMID:39794284 SUPPORT Other

"We recommend vigilance for ocular symptoms of vitamin A deficiency, which should prompt measurement of retinol levels and supplementation if low (Grade B, moderate)."

The guideline recommendation covering this treatment.

Growth Hormone for Short Stature

Action: Pharmacotherapy NCIT:C15986

Agent: somatropin NCIT:C837

Platform: Protein replacement

Reserved for growth failure that persists despite adequate metabolic control, or for CKD stage 3 or higher. It is a weak recommendation on low-grade evidence, and it matters mainly in Dent disease 2, where growth retardation affects 60-80% of patients.

Mechanism Target:

MODULATES Growth delay — Symptomatic treatment of the growth phenotype, not of any upstream mechanism node.

Show evidence (1 reference)

PMID:39794284 SUPPORT Other

"We suggest that treatment with growth hormone (GH) for short stature in patients with DD should only be considered if growth failure persists despite adequate metabolic control or in CKD 3 or higher (Grade D, weak)."

The guideline recommendation and its restriction to second-line use.

Kidney Transplantation

Action: kidney transplantation Ontology label: Organ Transplantation NCIT:C15289

Platform: Surgery

Definitive treatment for kidney failure. Because the lesion is in the kidney, a transplanted organ is not affected and the disease does not recur. Living related donation needs care given that maternal relatives may be carriers, and the guideline advises prioritising unrelated donation when donor risk cannot be assessed.

Mechanism Target:

RESTORES Chronic kidney disease — Replaces the failed organ; since the genetic defect is not expressed in the graft, the tubulopathy does not return.

Show evidence (1 reference)

PMID:39794284 SUPPORT Other

"The disease does not recur after kidney transplantation."

Establishes that transplantation is curative for the renal disease rather than merely supportive.

Show evidence (1 reference)

PMID:39794284 SUPPORT Other

"When risk is difficult to assess, priority should be given to unrelated kidney transplantation"

Records the donor-selection caution that follows from X-linked carrier status in the maternal line.

Renin-Angiotensin Blockade

Action: Pharmacotherapy NCIT:C15986

Agent: ACE inhibitor NCIT:C247 angiotensin receptor blocker NCIT:C66930

Platform: Small molecule

ACE inhibitors and ARBs are used in 11-42% of patients, on the reasoning that nephrotic-range proteinuria, glomerulosclerosis, podocyte effacement and podocyte expression of CLCN5 and OCRL make this a glomerular disease amenable to antiproteinuric therapy. The guideline recommends against routine use. Published case series show no fall in proteinuria, which is unsurprising given that the proteinuria is tubular rather than glomerular in origin, and the hypovolaemia risk is raised in a salt-losing tubulopathy. This treatment is curated because it is widely used, not because it is endorsed.

Mechanism Target:

MODULATES Failure of Proximal Tubular Protein Reabsorption — The intended antiproteinuric target is glomerular, but the proteinuria of Dent disease arises at this tubular node, which is the mechanistic reason the drugs fail here.

Show evidence (1 reference)

PMID:39794284 REFUTE Other

"which is not unexpected considering the tubular (rather than glomerular) origin of proteinuria in DD"

Refutes the antiproteinuric rationale on exactly the mechanistic grounds this pathograph encodes.

Show evidence (2 references)

PMID:39794284 REFUTE Other

"We suggest that ACE inhibitors (ACEis) or angiotensin receptor blockers (ARBs) should not be used routinely as nephroprotective treatment in patients with DD (Grade C, moderate)."

The guideline recommendation against routine renin-angiotensin blockade in this disease.

PMID:39794284 NO_EVIDENCE Other

"However, no studies have addressed the effects of ACEis/ARBs on CKD progression in patients with DD or in animal models."

Records the complete absence of outcome data for this widely used treatment.

Genetic Testing and Counselling

Category: Diagnostic Action: genetic counseling Ontology label: Genetic Counseling NCIT:C15240

Genetic testing of both CLCN5 and OCRL is a strong recommendation for any male with isolated persistent low-molecular-weight proteinuria or with mixed nephrotic-range proteinuria, because it both confirms the diagnosis and separates the two subtypes, which differ in extrarenal surveillance and in thiazide tolerance. Testing extends to the mother to establish carrier versus de novo status.

Show evidence (3 references)

PMID:39794284 SUPPORT Other

"We recommend genetic testing to confirm a diagnosis of DD in males and include both CLCN5 and OCRL genes to differentiate between DD1 and DD2 (Grade B, strong)."

The strong guideline recommendation for dual-gene testing and the reason for it.

PMID:39794284 SUPPORT Other

"We recommend performing genetic testing in relatives of males with DD as follows: Mothers in order to determine whether the mother is a heterozygous carrier or if the variant is de novo (Grade X, strong)."

Extends testing to the maternal line, which is what determines recurrence risk in an X-linked disorder.

PMID:22876375 SUPPORT REVIEW SYNTHESIS Other

"Carrier testing for at-risk female relatives and prenatal and preimplantation genetic testing are possible if the pathogenic variant in the family has been identified."

GeneReviews states the reproductive testing options this treatment entry offers, which is the counselling half of the entry rather than the diagnostic half.

Avoidance of Nephrotoxic Agents

Action: avoidance of nephrotoxic agents Ontology label: Supportive Care NCIT:C15747

GeneReviews lists avoidance of potential renal toxins among agents and circumstances to avoid. In a disease whose defining trajectory is progressive loss of kidney function, withholding an avoidable nephrotoxic insult is a management action in its own right rather than general caution. The named classes are non-steroidal anti-inflammatory drugs, aminoglycoside antibiotics and intravenous contrast agents.

Mechanism Target:

INHIBITS Tubulointerstitial Fibrosis and Progressive Nephron Loss — Removing an avoidable toxic insult to the proximal tubule acts on the same node that the disease itself drives; it does not treat the underlying lesion.

Show evidence (1 reference)

PMID:22876375 SUPPORT REVIEW SYNTHESIS Other

"Exposure to potential renal toxins (nonsteroidal anti-inflammatory drugs, aminoglycoside antibiotics, and intravenous contrast agents)."

The GeneReviews agents-to-avoid list, naming the three specific drug classes.

🔬

Diagnosis

2

Establishing the diagnosis in a male proband (PRESENT)

The diagnosis rests on the typical tubular findings together with an X-linked family history and a pathogenic variant in CLCN5 or OCRL, which is also what separates the two genetic forms from each other.

Show evidence (2 references)

PMID:22876375 SUPPORT REVIEW SYNTHESIS Other

"The diagnosis is established in a male proband with the typical clinical findings and a family history consistent with X-linked inheritance who has a pathogenic variant in either CLCN5 (known as Dent disease 1) or in OCRL (known as Dent disease 2)."

The GeneReviews diagnostic statement, naming both the clinical picture and the confirmatory molecular test.

PMID:22876375 SUPPORT REVIEW SYNTHESIS Other

"Heterozygous females are most likely to be identified by familial molecular genetic testing related to a male proband."

States how carrier females come to attention, which is why the entry does not model a female-proband diagnostic route.

Surveillance of kidney function and calcium excretion (PRESENT)

Annual monitoring of urinary calcium excretion, glomerular filtration rate and the CKD staging parameters, increasing in frequency once chronic kidney disease is established.

Show evidence (1 reference)

PMID:22876375 SUPPORT REVIEW SYNTHESIS Other

"Monitor at least annually urinary calcium excretion, renal function (glomerular filtration rate), and the parameters used to stage CKD"

The GeneReviews surveillance schedule, which is the management action that tracks the two mechanisms this entry models as driving progression.

📈

Progression

3

Biochemical onset

Age: Childhood, often before 10 years

Low-molecular-weight proteinuria is present throughout the course and is usually the first abnormality, frequently found incidentally on screening or during work-up of proteinuria in a boy. Hypercalciuria is detected in most children and young adults but in only a minority of adults.

Show evidence (1 reference)

PMID:39794284 SUPPORT Other

"While proteinuria is present during the entire course of the disease, hypercalciuria is detected in 61%–73% of children and young adults compared with 14%–19% of adults"

Establishes proteinuria as the constant finding and hypercalciuria as the age-dependent one.

Mineral and skeletal complications

Age: Childhood to early adulthood

Nephrocalcinosis appears first and is often detectable on childhood ultrasound; discrete kidney stones manifest later. Rickets, urolithiasis, or an incidentally discovered reduction in kidney function may all be the presenting problem.

Show evidence (2 references)

PMID:39794284 SUPPORT Other

"Nephrocalcinosis is often detectable from childhood while kidney stones manifest at a later age"

Gives the temporal ordering of the two mineral complications.

PMID:39794284 SUPPORT Other

"Other subjects may present with rickets or urolithiasis with or without nephrocalcinosis, or simply with previously undiagnosed CKD"

Records the alternative presentations at this stage of the course.

Progressive chronic kidney disease and kidney failure

Age: Third to fifth decade

Kidney failure occurs in 30-80% of affected males between the third and fifth decades, with roughly 40% of patients aged 30-40, a third of those aged 40-50, and three of four aged 50-60 in one series already in kidney failure. Progression is variable within one family, so the genotype does not predict the individual trajectory.

Show evidence (2 references)

PMID:39794284 SUPPORT Other

"Four out of ten patients aged 30–40 years, three out of nine aged 40–50 years, and three out of four aged 50–60 years had kidney failure"

Provides the age-stratified kidney-failure counts summarised in this phase.

PMID:20946626 SUPPORT Other

"Progression to end-stage renal failure occurs between the 3rd and 5th decades of life in 30-80% of affected males."

Independent review gives the same timing and proportion.

📊

Prevalence

2

Japan, France, and Great Britain national registries

Point Prevalence 0.15 per 100,000 (0.1–0.25) <1 in 1,000,000

Estimated at between 1 in 400,000 and 1 in 1,000,000 from the Japanese (n=91), French (n=108), and British (n=62) national registries; the true prevalence is probably higher because the phenotype is variable and the course insidious. Normalised here as 0.1-0.25 per 100,000.

Show evidence (2 references)

PMID:39794284 SUPPORT Other

"a prevalence of between 1 in 400 000 and 1 in 1 000 000 may be estimated"

The ERA/ESPN clinical practice recommendations give the registry-derived prevalence range normalised into this record.

PMID:39794284 SUPPORT Other

"Still, the true prevalence of DD is probably higher due to the variable phenotype and insidious disease course."

Records the guideline's own caveat that the registry-derived estimate is a lower bound.

Reported families worldwide as of 2010

Cases In Literature Ultra Rare

At the time of the 2010 Orphanet review the disorder had been reported in around 250 families, and no population prevalence had been established.

Show evidence (1 reference)

PMID:20946626 SUPPORT Other

"Prevalence is unknown; the disorder has been reported in around 250 families to date."

Establishes the published-case count and that no population prevalence was available at that time.

🔀

Differential Diagnoses

3

Conditions with similar clinical presentations that must be differentiated from Dent Disease:

Lowe syndrome MONDO:0010645

Overlapping Features The other OCRL disease, and the closest differential for Dent disease 2 specifically. It is curated as its own dismech entry. The two sit on one allelic spectrum but are clinically distinct.

Distinguishing Features

Dense bilateral congenital cataract, glaucoma, generalised hypotonia, and intellectual disability are obligate or typical in Lowe syndrome and absent or mild in Dent disease 2.
Truncating OCRL variants in exons 8-24 give Lowe syndrome; those in exons 1-7 give Dent disease 2.
CKD progresses faster in Lowe syndrome than in Dent disease 2.

Show evidence (2 references)

PMID:39794284 SUPPORT Other

"Lowe syndrome ( OCRL ) | Congenital cataracts, glaucoma, general hypotonia, mental retardation, CKD"

The guideline's own differential-diagnosis table row naming the discriminating features.

PMID:27708066 SUPPORT Human Clinical

"Survival analysis showed that LS was also associated with a faster CKD progression than DD2 (P < 0.01)."

Quantifies the renal-outcome difference between the two OCRL phenotypes.

Nephropathic cystinosis MONDO:0016239

Overlapping Features The commonest inherited cause of a full renal Fanconi syndrome in childhood, and a routine exclusion before or alongside Dent disease testing.

Distinguishing Features

Corneal cystine crystals and multisystem storage disease, absent in Dent disease.
A complete Fanconi syndrome rather than the incomplete, protein-reabsorption-dominant picture of Dent disease.

Show evidence (1 reference)

PMID:39794284 SUPPORT Other

"Nephropathic cystinosis ( CTNS ) | Poor growth, rickets, corneal cystine crystals, CKD"

The guideline's differential table row giving the discriminating features of cystinosis.

Idiopathic focal segmental glomerulosclerosis

Overlapping Features Not a competing genetic diagnosis so much as the label Dent disease is wrongly given. Because the tubular protein load can be nephrotic-range and biopsy shows glomerulosclerosis with foot-process effacement, patients are treated as steroid-resistant nephrotic syndrome; 13% of one biopsy series had a repeat biopsy for steroid-resistant proteinuria.

Distinguishing Features

Serum albumin is normal and there is no oedema, despite nephrotic-range total protein.
Urinary protein is low-molecular-weight in origin, demonstrable by retinol-binding protein, beta-2-microglobulin, or an alpha-1-microglobulin/creatinine ratio above 120 mg/g.

Show evidence (2 references)

PMID:27697782 SUPPORT Human Clinical

"A repeat biopsy for steroid-resistant proteinuria was performed in 13% (four of 30) of the patients."

Documents that Dent disease patients are in practice managed as steroid-resistant nephrotic syndrome before the diagnosis is made.

PMID:39794284 SUPPORT Other

"Affected individuals may present nephrotic-range proteinuria which may be misinterpreted and cause diagnostic delay."

States the misdiagnosis explicitly as a recognised cause of diagnostic delay.

🐁

Animal Models

4

Clcn5 knockout mouse

The founding mouse model. Disrupting clcn5 reproduces the proteinuria of Dent disease and localises its cause to failed apical proximal tubular endocytosis. It also produced the vitamin D / PTH account of hypercalciuria that the human literature still uses.

Species

Mouse

Genotype

Clcn5 null (clcn5 gene disruption, hemizygous male)

Genes

CLCN5 hgnc:2023

Publication

PMID:11099045

Pathograph links

Megalin and Cubilin Trafficking Failure recapitulates fidelity: high observes: cellular Reproduces the endocytic failure of the proximal tubule, both receptor-mediated and fluid-phase, with slowed internalization of apical transporters.

Limitations: A complete null, whereas most human disease-causing CLCN5 alleles are missense or truncating variants with residual protein handling consequences that a null cannot represent.

Readouts

Apical proximal tubular endocytosis

Direction: DECREASED

Interpretation: Direct functional readout of the node in this model.

Show evidence (1 reference)

PMID:11099045 SUPPORT Model Organism

"Here we show that disruption of the mouse clcn5 gene causes proteinuria by strongly reducing apical proximal tubular endocytosis."

Reports the measurement and its direction.

Show evidence (1 reference)

PMID:11099045 SUPPORT Model Organism

"Both receptor-mediated and fluid-phase endocytosis are affected, and the internalization of the apical transporters NaPi-2 and NHE3 is slowed."

Supports treating this model as informative for the trafficking node.

Urinary Loss of Vitamin D-Binding Protein and Parathyroid Hormone recapitulates fidelity: moderate observes: organism The model is the origin of the two-opposing-effects account of hypercalciuria in this disease.

Limitations: The authors present the net effect on hypercalciuria as probable rather than demonstrated, and the balance has not been measured directly in patients.

Show evidence (1 reference)

PMID:11099045 SUPPORT Model Organism

"This may be caused by an increased stimulation of luminal parathyroid hormone (PTH) receptors owing to the observed decreased tubular endocytosis of PTH."

Reports the PTH handling defect that this node describes.

Clcn5 knock-in missense mouse

A knock-in model carrying the most representative class of ClC-5 missense variant found in patients, rather than a null. It reproduces the Dent disease 1 phenotype with disturbed endolysosomal and autophagic function, and with age develops fibrosis and apoptosis, so it addresses the progression step that the knockout leaves unexplained.

Species

Mouse

Genotype

Clcn5 knock-in carrying a representative Dent disease 1 missense variant

Genes

CLCN5 hgnc:2023

Publication

PMID:39019097

Pathograph links

Tubulointerstitial Fibrosis and Progressive Nephron Loss recapitulates fidelity: moderate observes: tissue With ageing the model accumulates renal fibrosis and apoptosis alongside metabolic change, which is the transition from tubulopathy to CKD.

Limitations: Progression in the mouse is compressed relative to the decades-long human course, and the proposed Lipocalin-2/24p3R crosstalk has not been shown in patients.

Readouts

Renal fibrosis and apoptosis with ageing

Direction: INCREASED

Interpretation: Histological correlate of the progression node in this model.

Show evidence (1 reference)

PMID:39019097 SUPPORT Model Organism

"With ageing, KI mice showed increased renal fibrosis, apoptosis and major changes in cell metabolic functions as already suggested in previous DD models."

Reports the measurement and its direction.

Show evidence (1 reference)

PMID:39019097 SUPPORT Model Organism

"These mice showed a characteristic DD type 1 phenotype accompanied by altered endo-lysosomal system and autophagy functions."

Supports treating this model as informative for the disease's progressive renal pathology.

Drosophila nephrocyte ClC-c depletion model

Drosophila nephrocytes share properties with both podocytes and proximal tubule cells. Depleting the CLCN5 ortholog reproduces loss of Cubilin from the plasma membrane and reduced protein uptake, and revealed a secretory-pathway mechanism - Cubilin retained in the endoplasmic reticulum with Amnionless reduced - subsequently confirmed in ClC-5 knockout mice.

Species

Fruit fly

Genotype

Nephrocyte-specific depletion of ClC-c, the Drosophila ortholog of CLCN5

Publication

PMID:41690574

Pathograph links

Megalin and Cubilin Trafficking Failure recapitulates fidelity: moderate observes: cellular Reproduces receptor loss from the cell surface and identifies an earlier endoplasmic-reticulum export step in the mechanism.

Limitations: A fly nephrocyte is not a mammalian proximal tubule cell and the fly has no megalin ortholog in the mammalian sense, so only the Cubilin/Amnionless arm of the receptor complex is modelled. The mammalian confirmation is in mice rather than patients.

Readouts

Cubilin at the nephrocyte plasma membrane

Direction: DECREASED

Interpretation: Loss of the receptor from the surface is the defining lesion of this node.

Show evidence (1 reference)

PMID:41690574 SUPPORT Model Organism

"Upon depletion of ClC-c, the fly ortholog of CLCN5, Cubilin was lost from the plasma membrane of nephrocytes, leading to a strong decrease in albumin uptake and ectopic slit diaphragms."

Reports the measurement and its direction.

Show evidence (1 reference)

PMID:41690574 SUPPORT Model Organism

"Our findings suggest that in addition to its endosomal role ClC-c/ClC-5 acts in the secretory pathway to promote surface trafficking of the Cubilin/Amnionless complex."

States the mechanistic conclusion this model contributes to the node.

OCRL-deficient zebrafish

Zebrafish ocrl models cover both Lowe syndrome and Dent disease 2. They show defective pronephric endocytosis, abnormal lysosomal function and tubule shortening, which accounts for the low-molecular-weight proteinuria of both conditions, and they are tractable enough that chemical and genetic rescue makes a phenotypic drug screen realistic.

Species

Zebrafish

Genotype

ocrl morphant and mutant lines

Genes

OCRL hgnc:8108

Publication

PMID:40778266

Pathograph links

Endosomal PI(4,5)P2 Accumulation and Actin Dysregulation partially recapitulates fidelity: moderate observes: cellular The renal tubular arm of the model reproduces the endocytic and lysosomal consequences of OCRL loss.

Limitations: The fish models do not separate Dent disease 2 from Lowe syndrome, since both are produced by the same ocrl loss; the human distinction rests on variant position and residual isoform expression, which these lines do not reproduce. Whether the neurodevelopmental defects lie downstream of trafficking or of ciliary dysfunction is unresolved in the model itself.

Show evidence (1 reference)

PMID:40778266 SUPPORT Model Organism

"OCRL-deficient zebrafish also have a renal tubular phenotype, with defective endocytosis, abnormal lysosomal function, and shortening of the renal tubule."

Supports treating the fish as informative for the endosomal trafficking node.

Ocrl knockout mice are a notable negative: they do not reproduce the human disease, which is attributed to compensation by the paralog Inpp5b. That is part of why non-mammalian models carry disproportionate weight for Dent disease 2.

Show evidence (1 reference)

PMID:40778266 SUPPORT Model Organism

"These defects can account for the low molecular weight proteinuria seen in Lowe syndrome and Dent-2 disease and may explain the other renal features seen in both conditions."

Connects the model's cellular defects to the defining human phenotype.

{ }

Source YAML

click to show

name: Dent Disease
category: Mendelian
creation_date: "2026-09-11T00:00:00Z"
synonyms:
- Dent's disease
- X-linked recessive nephrolithiasis
- X-linked recessive hypercalciuric hypophosphataemic rickets
- Low-molecular-weight proteinuria with hypercalciuria and nephrocalcinosis
- Dent disease 1
- Dent disease 2
description: >
  Dent disease is a rare X-linked proximal tubulopathy defined by
  low-molecular-weight proteinuria together with hypercalciuria, and complicated
  in a large fraction of affected males by nephrocalcinosis, nephrolithiasis,
  rickets or osteomalacia, and progressive chronic kidney disease reaching
  kidney failure between the third and fifth decades. Two genetic forms are
  recognised: Dent disease 1, caused by inactivating CLCN5 variants that remove
  the electrogenic 2Cl-/H+ exchanger ClC-5 from proximal tubular subapical
  endosomes, and Dent disease 2, caused by OCRL variants that reduce
  phosphatidylinositol 4,5-bisphosphate 5-phosphatase activity on the same
  endosomal compartment. Both converge on failure of the megalin/cubilin
  receptor-mediated endocytic apparatus of the proximal tubule, which is why the
  renal phenotypes overlap. A quarter to a third of clinically typical patients
  carry neither a CLCN5 nor an OCRL variant. Because total urinary protein
  excretion can reach the nephrotic range, the disease is frequently
  misinterpreted as a glomerular disease and diagnosis is delayed.
disease_term:
  preferred_term: Dent disease
  term:
    id: MONDO:0015612
    label: Dent disease
parents:
- X-linked genetic disorders
- Renal tubular transport disease
- Inherited renal tubular disease
prevalence:
- population: Japan, France, and Great Britain national registries
  measure_type: POINT_PREVALENCE
  prevalence_class: BELOW_1_IN_1000000
  rate_per_100000: 0.15
  rate_low: 0.1
  rate_high: 0.25
  notes: >-
    Estimated at between 1 in 400,000 and 1 in 1,000,000 from the Japanese
    (n=91), French (n=108), and British (n=62) national registries; the true
    prevalence is probably higher because the phenotype is variable and the
    course insidious. Normalised here as 0.1-0.25 per 100,000.
  evidence:
  - reference: PMID:39794284
    reference_title: "Dent disease: clinical practice recommendations."
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "a prevalence of between 1 in 400 000 and 1 in 1 000 000 may be estimated"
    explanation: The ERA/ESPN clinical practice recommendations give the registry-derived prevalence range normalised into this record.
  - reference: PMID:39794284
    reference_title: "Dent disease: clinical practice recommendations."
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "Still, the true prevalence of DD is probably higher due to the variable phenotype and insidious disease course."
    explanation: Records the guideline's own caveat that the registry-derived estimate is a lower bound.
- population: Reported families worldwide as of 2010
  measure_type: CASES_IN_LITERATURE
  prevalence_class: ULTRA_RARE
  notes: >-
    At the time of the 2010 Orphanet review the disorder had been reported in
    around 250 families, and no population prevalence had been established.
  evidence:
  - reference: PMID:20946626
    reference_title: "Dent's disease."
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "Prevalence is unknown; the disorder has been reported in around 250 families to date."
    explanation: Establishes the published-case count and that no population prevalence was available at that time.
inheritance:
- name: X-linked recessive inheritance
  inheritance_term:
    preferred_term: X-linked recessive inheritance
    term:
      id: HP:0001419
      label: X-linked recessive inheritance
  description: >-
    Both genetic forms are X-linked. The full phenotype is essentially confined
    to hemizygous males; heterozygous female carriers show attenuated features,
    most often low-molecular-weight proteinuria and, less consistently,
    hypercalciuria. De novo variants are not rare, accounting for roughly 12% of
    Dent disease 1 and up to 30% of Dent disease 2 cases.
  evidence:
  - reference: PMID:20946626
    reference_title: "Dent's disease."
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "These features are generally found in males only, and may be present in early childhood, whereas female carriers may show a milder phenotype."
    explanation: States the X-linked sex-limited expression pattern with attenuated carrier phenotype.
  - reference: PMID:20946626
    reference_title: "Dent's disease."
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "For example, the milder features of LMW proteinuria and hypercalciuria are found in approximately 70% and 50% of females carriers, respectively, whilst the more severe manifestations of nephrolithiasis have been reported in only 10 females and end-stage renal failure has been reported in only 1 female [8]."
    explanation: Quantifies the attenuated carrier-female phenotype that the X-linked recessive designation predicts.
  - reference: PMID:39794284
    reference_title: "Dent disease: clinical practice recommendations."
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "De novo variants account for ∼12% of DD1 cases"
    explanation: Records the de novo variant fraction, which bears directly on recurrence counselling in an X-linked disorder.
  - reference: PMID:22876375
    reference_title: "Dent Disease."
    supports: SUPPORT
    quote_role: REVIEW_SYNTHESIS
    evidence_source: OTHER
    snippet: "If the mother of the proband has a pathogenic variant, the chance of transmitting it in each pregnancy is 50%."
    explanation: The GeneReviews transmission-risk figure, which is the number genetic counselling turns on and
      which this entry previously stated nowhere.
  - reference: PMID:22876375
    reference_title: "Dent Disease."
    supports: SUPPORT
    quote_role: REVIEW_SYNTHESIS
    evidence_source: OTHER
    snippet: "Affected males pass the pathogenic variant to all of their daughters (who become carriers) and none of their sons."
    explanation: Completes the X-linked transmission pattern from the affected-male side.
has_subtypes:
- name: DD1
  display_name: Dent disease 1 (CLCN5-related)
  classification: genetic
  subtype_term:
    preferred_term: Dent disease type 1
    term:
      id: MONDO:0010225
      label: Dent disease type 1
  description: >
    The commonest form, accounting for roughly half to two-thirds of patients.
    Inactivating CLCN5 variants remove or disable the electrogenic 2Cl-/H+
    exchanger ClC-5 from the early endosomes of the proximal tubular subapical
    compartment. The renal phenotype is therefore a pure proximal tubulopathy
    with no obligate extrarenal features, although rickets, osteomalacia, and
    growth retardation occur secondary to the tubular losses.
  genes:
  - preferred_term: CLCN5
    term:
      id: hgnc:2023
      label: CLCN5
  inheritance:
  - name: X-linked recessive inheritance
  evidence:
  - reference: PMID:39794284
    reference_title: "Dent disease: clinical practice recommendations."
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "DD1 (MIM #300 009) is caused by inactivating variants in the CLCN5 gene (located on Xp11.22), which encodes the electrogenic 2Cl−/H+ exchanger ClC-5"
    explanation: Defines Dent disease 1 as the CLCN5-related form and names the affected transporter and locus.
  - reference: PMID:20946626
    reference_title: "Dent's disease."
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "Thus, there is genetic heterogeneity for Dent's disease, with approximately 50-60% of patients having CLCN5 mutations (Dent disease 1), ~15% harbouring OCRL1 mutations (Dent disease 2) and the remaining 25-35% of patients having neither CLCN5 nor OCRL1 mutations but possibly defects in other genes."
    explanation: Quantifies the share of patients attributable to CLCN5 and so the relative weight of this subtype.
- name: DD2
  display_name: Dent disease 2 (OCRL-related)
  classification: genetic
  subtype_term:
    preferred_term: Dent disease type 2
    term:
      id: MONDO:0010359
      label: Dent disease type 2
  description: >
    Roughly 15% of patients carry OCRL variants instead. The proximal tubular
    phenotype largely overlaps Dent disease 1, but mild extrarenal features may
    be present: raised muscle enzymes, mild developmental delay, short stature,
    and occasionally punctate cataract. The same gene causes Lowe syndrome,
    which dismech curates as a separate, more severe multisystem entry
    (Lowe_Syndrome); DD2 is modelled here as a subtype of Dent disease rather
    than duplicated there, matching the split that entry records. In the largest
    DD2 series 39% of patients had at least one extrarenal sign, with muscle
    findings much commoner than ocular ones, and the authors concluded DD2 is
    clinically distinct from Lowe syndrome rather than simply a mild version of
    it.
  genes:
  - preferred_term: OCRL
    term:
      id: hgnc:8108
      label: OCRL
  inheritance:
  - name: X-linked recessive inheritance
  evidence:
  - reference: PMID:39794284
    reference_title: "Dent disease: clinical practice recommendations."
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "Extrarenal manifestations of patients with DD2 are very mild compared with full-blown Lowe syndrome and may include punctuated congenital cataract, mild developmental delay, and short stature"
    explanation: Defines the DD2 extrarenal profile and contrasts it with Lowe syndrome, which is the basis for keeping the two entries separate.
  - reference: PMID:39794284
    reference_title: "Dent disease: clinical practice recommendations."
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "The manifestations of proximal tubular dysfunction overlap in patients with DD1 and DD2"
    explanation: Justifies curating DD2 as a subtype of the same disease rather than a separate entry, since the renal mechanism and phenotype are shared.
  - reference: PMID:34680992
    reference_title: "Genotype Phenotype Correlation in Dent Disease 2 and Review of the Literature: OCRL Gene Pleiotropism or Extreme Phenotypic Variability of Lowe Syndrome?"
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "The frequency of patients with at least one ES was 39%. Muscle findings are the most common ES (52%), while ocular findings are less common (11%)."
    explanation: Largest DD2 cohort quantifies how often extrarenal signs occur and which organ systems dominate.
  - reference: PMID:34680992
    reference_title: "Genotype Phenotype Correlation in Dent Disease 2 and Review of the Literature: OCRL Gene Pleiotropism or Extreme Phenotypic Variability of Lowe Syndrome?"
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "DD2 is distinct from LS. The mutation site and the mutation type largely determine the DD2 phenotype."
    explanation: Directly supports the lump/split decision to keep DD2 inside the Dent disease entry and Lowe syndrome as its own entity.
genetic:
- name: CLCN5
  subtype: DD1
  gene_term:
    preferred_term: CLCN5
    term:
      id: hgnc:2023
      label: CLCN5
  association: Loss-of-function
  presence: Positive
  relationship_type: CAUSATIVE
  variant_origin: GERMLINE
  frequency: approximately 50-60% of patients with Dent disease
  notes: >
    More than 300 distinct disease-causing CLCN5 variants have been described,
    spanning missense, nonsense, frameshift, splice-site, and large deletion
    classes, with no clear mutational hotspot. Missense variants have been
    sorted experimentally into three cell-biological classes (endoplasmic
    reticulum retention and degradation; normal trafficking with defective
    endosomal acidification; altered endosomal distribution with preserved
    acidification), but this classification has not been shown to predict
    clinical severity. Genotype-phenotype correlation in DD1 remains contested:
    a large series found no difference in age at diagnosis, eGFR, proteinuria,
    or hypercalciuria between severe and missense variants, while two more
    recent series reported associations with pore or CBS-domain variants and
    with truncating variants among patients reaching kidney failure.
  evidence:
  - reference: PMID:39794284
    reference_title: "Dent disease: clinical practice recommendations."
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "To date, more than 300 distinct disease-causing variants in the CLCN5 gene have been identified."
    explanation: Establishes the breadth of the CLCN5 allelic spectrum underlying Dent disease 1.
  - reference: PMID:39794284
    reference_title: "Dent disease: clinical practice recommendations."
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "There are no clear mutation hotspots as only a small number of recurrent variants has been reported in different geographic areas"
    explanation: Records that CLCN5 variants are largely private, which bears on diagnostic sequencing strategy.
  - reference: PMID:39794284
    reference_title: "Dent disease: clinical practice recommendations."
    supports: REFUTE
    evidence_source: OTHER
    snippet: "Blanchard et al. found no difference in age at diagnosis, estimated glomerular filtration rate (eGFR), proteinuria, or hypercalciuria, indicating that there is no correlation between genotype and phenotype in DD1"
    explanation: Refutes a simple genotype-severity correlation in Dent disease 1, which is why variant class is not used here to stratify prognosis.
  - reference: PMID:19019917
    reference_title: "Characterization of Dent's disease mutations of CLC-5 reveals a correlation between functional and cell biological consequences and protein structure."
    supports: SUPPORT
    evidence_source: IN_VITRO
    snippet: "This revealed three classes of Dent's disease-causing CLC-5 mutations. Class 1 mutations lead to endoplasmic reticulum retention and degradation of CLC-5. Class 2 mutations appear to have little effect on subcellular distribution of CLC-5 but cause defective function resulting in severe defects in endosomal acidification. Class 3 mutations lead to alterations in the endosomal distribution of CLC-5 but are otherwise able to support endosomal acidification."
    explanation: Defines the three experimentally characterised cell-biological consequences of CLCN5 missense variants.
  - reference: PMID:19019917
    reference_title: "Characterization of Dent's disease mutations of CLC-5 reveals a correlation between functional and cell biological consequences and protein structure."
    supports: SUPPORT
    evidence_source: IN_VITRO
    snippet: "Mutations result in functional defects that range from moderate reductions to complete loss of whole cell currents, although the severity of the functional defect rarely correlates with the severity of the disease."
    explanation: Supports treating in-vitro functional severity as uninformative about clinical severity in this disease.
- name: OCRL
  subtype: DD2
  gene_term:
    preferred_term: OCRL
    term:
      id: hgnc:8108
      label: OCRL
  association: Loss-of-function
  presence: Positive
  relationship_type: CAUSATIVE
  variant_origin: GERMLINE
  frequency: approximately 15% of patients with Dent disease
  notes: >
    OCRL variants cause both Dent disease 2 and the more severe Lowe syndrome.
    The position of a truncating variant largely determines which: variants in
    exons 1-7 give Dent disease 2, while exons 8-24 give Lowe syndrome, a
    difference attributed to an additional translation-initiation codon in exon
    8 that permits expression of a shortened but partly functional OCRL isoform.
    Missense variants associated with DD2 map to the 5-phosphatase domain.
    The correlation is not absolute: both phenotypes have been reported for five
    OCRL variants.
  evidence:
  - reference: PMID:39794284
    reference_title: "Dent disease: clinical practice recommendations."
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "Regarding the OCRL gene, a genotype–phenotype correlation is hypothesized because nearly all truncating variants associated with DD2 are located in exons 1–7, which encompass the PH domain, while variants associated with Lowe syndrome are located in exons 8–24"
    explanation: Gives the exon-position rule that separates Dent disease 2 from Lowe syndrome within one gene.
  - reference: PMID:39794284
    reference_title: "Dent disease: clinical practice recommendations."
    supports: REFUTE
    evidence_source: OTHER
    snippet: "Of note, both a Lowe syndrome and DD2 phenotype have been reported for five OCRL variants, arguing against a clear genotype–phenotype effect"
    explanation: Refutes a strict exon-position rule, so the DD2/Lowe boundary is not fully predictable from genotype.
  - reference: PMID:34586410
    reference_title: "Identification of novel OCRL isoforms associated with phenotypic differences between Dent disease-2 and Lowe syndrome."
    supports: SUPPORT
    evidence_source: IN_VITRO
    snippet: "We successfully cloned the novel isoform transcripts from OCRL exons 6-24, including the translation-initiation codons present in exon 8."
    explanation: >-
      Provides the molecular basis for the exon-position rule, since an internal
      start codon in exon 8 permits partial OCRL expression in Dent disease 2.
- name: Genetically unexplained Dent disease
  presence: Negative
  relationship_type: UNKNOWN
  frequency: approximately 25-35% of clinically typical patients
  notes: >
    A substantial minority of patients meeting the clinical and biochemical
    definition of Dent disease carry no identifiable CLCN5 or OCRL variant. No
    third locus has been confirmed. This block records the gap rather than
    asserting a gene; treat it as the residual class of the genetic
    differential.
  evidence:
  - reference: PMID:39794284
    reference_title: "Dent disease: clinical practice recommendations."
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "the remaining 25%–35% of patients having neither identifiable CLCN5 nor OCRL variants"
    explanation: Quantifies the genetically unexplained fraction of clinically typical Dent disease.
  - reference: PMID:20946626
    reference_title: "Dent's disease."
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "A few patients with Dent's disease do not harbour mutations in CLCN5 and OCRL1, pointing to the involvement of other genes."
    explanation: Independent review confirms an unexplained residue and that no additional locus has been established.
pathophysiology:
- name: ClC-5 Chloride-Proton Exchanger Loss of Function
  biological_scale: MOLECULAR
  role: trigger
  description: >
    In Dent disease 1 an inactivating CLCN5 variant removes or disables ClC-5,
    the electrogenic 2Cl-/H+ exchanger of the early endosomes of the subapical
    compartment of proximal tubular cells. This is the initiating molecular
    lesion; the restriction of the clinical picture to a proximal tubulopathy
    follows from where the protein is normally expressed. Missense variants
    reach this state by several routes - endoplasmic reticulum retention and
    degradation, loss of transport function with normal localisation, or
    mislocalisation within the endosomal system.
  genes:
  - preferred_term: CLCN5
    term:
      id: hgnc:2023
      label: CLCN5
  genetic_context:
    variant_origin: GERMLINE
    zygosity: HEMIZYGOUS
    functional_impact_category: LOSS_OF_FUNCTION
  molecular_functions:
  - preferred_term: 2Cl-/H+ exchange by ClC-5
    term:
      id: GO:0062158
      label: chloride:proton antiporter activity
    modifier: DECREASED
  cellular_components:
  - preferred_term: proximal tubular subapical early endosome
    term:
      id: GO:0005769
      label: early endosome
  cell_types:
  - preferred_term: kidney proximal convoluted tubule epithelial cell
    term:
      id: CL:1000838
      label: kidney proximal convoluted tubule epithelial cell
  locations:
  - preferred_term: renal proximal tubule
    term:
      id: UBERON:0004134
      label: proximal tubule
  evidence:
  - reference: PMID:39794284
    reference_title: "Dent disease: clinical practice recommendations."
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "The clinical presentation of DD1 as a proximal tubulopathy reflects the predominant expression of ClC-5 in the early endosomes of the subapical compartment of proximal tubular cells"
    explanation: Places the initiating lesion in the proximal tubular subapical endosome and explains why the phenotype is a proximal tubulopathy.
  - reference: PMID:19019917
    reference_title: "Characterization of Dent's disease mutations of CLC-5 reveals a correlation between functional and cell biological consequences and protein structure."
    supports: SUPPORT
    evidence_source: IN_VITRO
    snippet: "It is generally thought that the principal cause of Dent's disease (31) results from a loss of functional CLC-5 from the subapical endosomes of kidney proximal tubule cells leading to a defect in endosomal acidification and impaired protein reabsorption"
    explanation: States the consensus initiating mechanism and its immediate consequences, which are the downstream nodes here.
  downstream:
  - target: Defective Endosomal Acidification
    causal_link_type: DIRECT
    description: >-
      Loss of the endosomal chloride conductance removes the countercurrent that
      lets the V-ATPase acidify the vesicle lumen.
    evidence:
    - reference: PMID:20946626
      reference_title: "Dent's disease."
      supports: SUPPORT
      evidence_source: OTHER
      snippet: "Accordingly, the loss of the endosomal Cl- conductance mediated by ClC-5 would impair vesicular acidification, causing dysfunction of PT cells."
      explanation: Asserts the direct link from ClC-5 loss to failure of endosomal acidification.
  - target: Megalin and Cubilin Trafficking Failure
    causal_link_type: DIRECT
    description: >-
      Independently of, and in addition to, the acidification defect, ClC-5 loss
      produces a severe trafficking defect that strips megalin and cubilin from
      the brush border. A Drosophila nephrocyte model plus confirmation in
      Clcn5 knockout mice adds a secretory-pathway component, with Cubilin
      retained in the endoplasmic reticulum and its partner Amnionless reduced.
    evidence:
    - reference: PMID:39794284
      reference_title: "Dent disease: clinical practice recommendations."
      supports: SUPPORT
      evidence_source: MODEL_ORGANISM
      snippet: "Studies in Clcn5 knock-out and knock-in (KI) mice have demonstrated that inactivation of ClC-5 is associated with a severe trafficking defect in proximal tubular cells, with loss or reduced levels of megalin and cubilin at the brush border, impaired endocytosis and lysosomal processing of endocytosed ligands, and defective internalization of various apical transporters"
      explanation: Model-organism evidence that ClC-5 loss causes the megalin/cubilin trafficking failure directly.

- name: Defective Endosomal Acidification
  biological_scale: MOLECULAR
  description: >
    Progression along the endocytic pathway requires the V-ATPase to acidify
    each vesicle to about pH 5.0, which is what dissociates ligand from
    receptor and permits receptor recycling. That proton pumping needs a
    parallel chloride conductance for electroneutrality, and ClC-5 supplies it.
    Losing ClC-5 leaves positive charge accumulating in the lumen and
    acidification impaired. This node is necessary but not sufficient for the
    disease phenotype: a knock-in mouse converting the exchanger into an
    uncoupled chloride channel acidifies its endosomes normally and still
    reproduces the full renal phenotype, so luminal chloride accumulation rather
    than pH alone appears to carry part of the mechanism.
  cellular_components:
  - preferred_term: proximal tubular subapical early endosome
    term:
      id: GO:0005769
      label: early endosome
  biological_processes:
  - preferred_term: endosomal lumen acidification
    term:
      id: GO:0048388
      label: endosomal lumen acidification
    modifier: DECREASED
  evidence:
  - reference: PMID:20946626
    reference_title: "Dent's disease."
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "Endosomal acidification (up to pH 5.0), that is necessary for dissociation of the ligand-receptor complex, recycling of receptors to the apical membrane, and progression of ligands into lysosomes, is achieved by ATP-driven transport of cytosolic H+ through the V-ATPase."
    explanation: Establishes why endosomal pH matters for receptor recycling, which is the next node in the chain.
  - reference: PMID:20946626
    reference_title: "Dent's disease."
    supports: SUPPORT
    evidence_source: MODEL_ORGANISM
    snippet: "Furthermore, in vitro experiments have shown a decreased acidification of early endosomes in ClC-5-deficient mice"
    explanation: Demonstrates that the acidification defect is actually present in ClC-5-deficient tissue.
  - reference: PMID:20946626
    reference_title: "Dent's disease."
    supports: REFUTE
    evidence_source: MODEL_ORGANISM
    snippet: "Furthermore, both the KI and KO mouse showed impaired PT endocytosis, indicating that PT dysfunction in Dent's disease may occur despite normal acidification of the endosomes."
    explanation: Refutes the claim that failed acidification is the sole route to proximal tubular dysfunction, since the knock-in mouse acidifies normally and is still affected.
  downstream:
  - target: Megalin and Cubilin Trafficking Failure
    causal_link_type: DIRECT
    description: >-
      Without the pH drop the ligand-receptor complex does not dissociate and
      the receptor is not returned to the apical membrane.

- name: OCRL Phosphoinositide 5-Phosphatase Deficiency
  biological_scale: MOLECULAR
  role: trigger
  description: >
    In Dent disease 2 the initiating lesion is instead a reduction in OCRL
    activity. OCRL is a phosphatidylinositol 4,5-bisphosphate 5-phosphatase
    that sits on early endosomes and keeps PI(4,5)P2 low there. Variants in
    exons 1-7 permit expression of a shortened isoform from an internal start
    codon, which is why the resulting phenotype is Dent disease rather than the
    multisystem Lowe syndrome.
  genes:
  - preferred_term: OCRL
    term:
      id: hgnc:8108
      label: OCRL
  genetic_context:
    variant_origin: GERMLINE
    zygosity: HEMIZYGOUS
    functional_impact_category: PARTIAL_LOSS_OF_FUNCTION
  biological_processes:
  - preferred_term: phosphatidylinositol dephosphorylation
    term:
      id: GO:0046856
      label: phosphatidylinositol dephosphorylation
    modifier: DECREASED
  cellular_components:
  - preferred_term: early endosome
    term:
      id: GO:0005769
      label: early endosome
  evidence:
  - reference: PMID:39794284
    reference_title: "Dent disease: clinical practice recommendations."
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "OCRL encodes the PI(4,5)P2 5-phosphatase OCRL, which controls phosphatidylinositol moieties in the endolysosomal pathway by degrading PI(4,5)P2"
    explanation: Names the enzymatic activity lost in Dent disease 2 and the compartment where it acts.
  downstream:
  - target: Endosomal PI(4,5)P2 Accumulation and Actin Dysregulation
    causal_link_type: DIRECT

- name: Endosomal PI(4,5)P2 Accumulation and Actin Dysregulation
  biological_scale: CELLULAR
  description: >
    Reduced OCRL activity lets PI(4,5)P2 build up on early endosomal membranes.
    The excess lipid drives uncontrolled actin polymerisation into basket-like
    structures around the aberrant organelles, which physically obstructs
    receptor trafficking. This is the Dent disease 2 route into the same
    endocytic failure that ClC-5 loss produces in Dent disease 1.
  cellular_components:
  - preferred_term: early endosome
    term:
      id: GO:0005769
      label: early endosome
  biological_processes:
  - preferred_term: actin filament organization
    term:
      id: GO:0007015
      label: actin filament organization
    modifier: DYSREGULATED
  cell_types:
  - preferred_term: kidney proximal convoluted tubule epithelial cell
    term:
      id: CL:1000838
      label: kidney proximal convoluted tubule epithelial cell
  evidence:
  - reference: PMID:39794284
    reference_title: "Dent disease: clinical practice recommendations."
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "The increase in PI(4,5)P2 levels in early endosomes stimulates uncontrolled actin polymerization into ‘basket’ structures surrounding aberrant organelles, impairing the trafficking of different receptors, including megalin needed for receptor-mediated endocytosis"
    explanation: Traces the OCRL lesion through PI(4,5)P2 accumulation and actin disorganisation to impaired megalin trafficking.
  - reference: PMID:39794284
    reference_title: "Dent disease: clinical practice recommendations."
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "The fact that variants in OCRL generally mimic the proximal tubular dysfunction encountered in DD1 is explained by the association of the OCRL protein with early endosomes, where it acts to maintain low levels of phosphatidylinositol (PI) 4,5-bisphosphate (PI(4,5)P2) for proper endocytic trafficking"
    explanation: States explicitly that the DD1 and DD2 lesions converge on the same endosomal trafficking step, which is the structure of this pathograph.
  downstream:
  - target: Megalin and Cubilin Trafficking Failure
    causal_link_type: DIRECT

- name: Megalin and Cubilin Trafficking Failure
  biological_scale: CELLULAR
  description: >
    The convergence point of both genetic forms. Megalin and cubilin are the
    multiligand receptors of the apical brush border that perform
    receptor-mediated endocytosis in the proximal tubule. Whichever lesion is
    upstream, they are lost or reduced at the brush border and their cargo is
    no longer retrieved from the filtrate. A Drosophila nephrocyte model of
    Dent disease 1, confirmed in ClC-5 knockout mice, adds an earlier
    secretory-pathway step, with Cubilin accumulating in the endoplasmic
    reticulum and Amnionless reduced overall, so the receptor complex may never
    reach the surface rather than only failing to recycle.
  cell_types:
  - preferred_term: kidney proximal convoluted tubule epithelial cell
    term:
      id: CL:1000838
      label: kidney proximal convoluted tubule epithelial cell
  locations:
  - preferred_term: renal proximal tubule
    term:
      id: UBERON:0004134
      label: proximal tubule
  biological_processes:
  - preferred_term: receptor-mediated endocytosis
    term:
      id: GO:0006898
      label: receptor-mediated endocytosis
    modifier: DECREASED
  - preferred_term: endocytic recycling
    term:
      id: GO:0032456
      label: endocytic recycling
    modifier: DECREASED
  evidence:
  - reference: PMID:20946626
    reference_title: "Dent's disease."
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "These vesicles belong to the receptor-mediated endocytic pathway, which involves the multiligand receptors, megalin and cubilin, located at the apical brush border of PT cells"
    explanation: Identifies the receptor system whose failure is the node.
  - reference: PMID:11099045
    reference_title: "ClC-5 Cl- -channel disruption impairs endocytosis in a mouse model for Dent's disease."
    supports: SUPPORT
    evidence_source: MODEL_ORGANISM
    snippet: "Here we show that disruption of the mouse clcn5 gene causes proteinuria by strongly reducing apical proximal tubular endocytosis."
    explanation: Original knockout mouse demonstrating that the endocytic failure is what produces the proteinuria.
  - reference: PMID:41690574
    reference_title: "A Drosophila model for Dent's disease type 1 revealed impaired endoplasmic reticulum export of Cubilin as pathogenic mechanism."
    supports: SUPPORT
    evidence_source: MODEL_ORGANISM
    snippet: "Upon depletion of ClC-c, the fly ortholog of CLCN5, Cubilin was lost from the plasma membrane of nephrocytes, leading to a strong decrease in albumin uptake and ectopic slit diaphragms. Importantly, Cubilin exhibited a strong accumulation in the endoplasmic reticulum, while its binding partner Amnionless was overall reduced."
    explanation: Adds a secretory-pathway component to the trafficking failure and shows the receptor is lost from the plasma membrane.
  - reference: PMID:41690574
    reference_title: "A Drosophila model for Dent's disease type 1 revealed impaired endoplasmic reticulum export of Cubilin as pathogenic mechanism."
    supports: SUPPORT
    evidence_source: MODEL_ORGANISM
    snippet: "Amnionless loss and ER retention of cubilin was confirmed in ClC-5 knockout mice, underscoring the relevance of this pathomechanism for Dent's disease."
    explanation: Confirms the invertebrate finding in a mammalian model, which is what makes it worth carrying in this node.
  downstream:
  - target: Failure of Proximal Tubular Protein Reabsorption
    causal_link_type: DIRECT
  - target: Urinary Loss of Vitamin D-Binding Protein and Parathyroid Hormone
    causal_link_type: DIRECT
    description: >-
      The megalin/cubilin complex is also what retrieves vitamin D-binding
      protein, 25(OH)-vitamin D3, and filtered PTH, so its loss diverts those
      ligands into the urine.
    evidence:
    - reference: PMID:20946626
      reference_title: "Dent's disease."
      supports: SUPPORT
      evidence_source: OTHER
      snippet: "Since the megalin/cubilin complex mediates the reabsorption of the vitamin D-binding protein, the 25(OH)-vitamin D3 and parathyroid hormone (PTH) that are ultrafiltrated by the glomerulus, the urinary loss of these mediators could potentially lead to opposite effects in PT cells, resulting in variable levels of active 1,25(OH)2-vitamin D3 levels in the serum"
      explanation: Names the specific cargo whose loss links the endocytic defect to calcium handling.
  - target: Generalized Proximal Tubular Solute Wasting
    causal_link_type: INDIRECT_KNOWN_INTERMEDIATES
    intermediate_mechanisms:
    - Defective internalization and steady-state redistribution of the apical transporters NaPi-2 and NHE3
    - Impaired lysosomal processing of endocytosed ligands
    evidence:
    - reference: PMID:11099045
      reference_title: "ClC-5 Cl- -channel disruption impairs endocytosis in a mouse model for Dent's disease."
      supports: SUPPORT
      evidence_source: MODEL_ORGANISM
      snippet: "Both receptor-mediated and fluid-phase endocytosis are affected, and the internalization of the apical transporters NaPi-2 and NHE3 is slowed."
      explanation: Shows the endocytic lesion also disturbs the apical transporters that handle phosphate and sodium-proton exchange.

- name: Failure of Proximal Tubular Protein Reabsorption
  biological_scale: TISSUE
  description: >
    Filtered low-molecular-weight proteins - beta-2-microglobulin,
    alpha-1-microglobulin, retinol-binding protein, and the vitamin-carrier
    proteins - are normally reclaimed almost completely by proximal tubular
    endocytosis. When that fails they appear in the urine. This is the obligate
    finding of the disease and, because the load can be large, total urinary
    protein may reach the nephrotic range without any glomerular lesion or
    hypoalbuminaemia.
  cell_types:
  - preferred_term: kidney proximal convoluted tubule epithelial cell
    term:
      id: CL:1000838
      label: kidney proximal convoluted tubule epithelial cell
  locations:
  - preferred_term: renal proximal tubule
    term:
      id: UBERON:0004134
      label: proximal tubule
  biological_processes:
  - preferred_term: protein transport
    term:
      id: GO:0015031
      label: protein transport
    modifier: DECREASED
  evidence:
  - reference: PMID:39794284
    reference_title: "Dent disease: clinical practice recommendations."
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "As low-molecular-weight proteins are reabsorbed by receptor-mediated endocytosis in proximal tubular cells, low-molecular-weight proteinuria is an obligate finding in DD."
    explanation: Directly links the endocytic failure to the obligate clinical finding.
  - reference: PMID:39794284
    reference_title: "Dent disease: clinical practice recommendations."
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "Affected individuals may present nephrotic-range proteinuria which may be misinterpreted and cause diagnostic delay."
    explanation: Records the diagnostic consequence of a tubular protein load large enough to look glomerular.
  downstream:
  - target: Low-molecular-weight proteinuria
    causal_link_type: DIRECT
  - target: Tubulointerstitial Fibrosis and Progressive Nephron Loss
    causal_link_type: INDIRECT_UNKNOWN_INTERMEDIATES
    description: >-
      The tubular protein load is the proximate injury, but the cited source
      says explicitly that the transition from proximal tubular dysfunction to
      progressive chronic kidney disease "remain[s] to be deciphered", so the
      intermediates are left unstated rather than inferred.
    evidence:
    - reference: PMID:39794284
      reference_title: "Dent disease: clinical practice recommendations."
      supports: SUPPORT
      evidence_source: OTHER
      snippet: "Early changes in proximal tubular cells, including proliferation, dedifferentiation, autophagy, and metabolic adaptation, may become maladaptive and promote inflammation and progression of tubulointerstitial fibrosis by various mechanisms"
      explanation: Attributes tubulointerstitial fibrosis to maladaptive proximal tubular cell responses, which
        is what makes this an edge from the protein-reabsorption failure node.
    - reference: PMID:39794284
      reference_title: "Dent disease: clinical practice recommendations."
      supports: SUPPORT
      evidence_source: OTHER
      snippet: "The mechanisms behind the transition from proximal tubular dysfunction to progressive chronic kidney disease (CKD) in DD remain to be deciphered."
      explanation: The same source's explicit statement that the intermediates are unknown, which is why this
        edge is INDIRECT_UNKNOWN_INTERMEDIATES rather than DIRECT.
  - target: Focal segmental glomerulosclerosis
    causal_link_type: INDIRECT_UNKNOWN_INTERMEDIATES
    description: >-
      Glomerular lesions are found on most Dent disease biopsies. Whether they
      arise from the tubular protein load, from podocyte expression of ClC-5 and
      OCRL, or from both is unsettled.
    evidence:
    - reference: PMID:39794284
      reference_title: "Dent disease: clinical practice recommendations."
      supports: SUPPORT
      evidence_source: OTHER
      snippet: "Emerging evidence also suggests that ClC-5 and OCRL may be expressed in human podocytes, potentially explaining the development of focal segmental glomerulosclerosis (FSGS) lesions observed in kidney biopsies of patients with DD1 and DD2"
      explanation: Records the current, explicitly tentative explanation for the glomerular lesion in a tubular disease.

- name: Urinary Loss of Vitamin D-Binding Protein and Parathyroid Hormone
  biological_scale: ORGANISM
  description: >
    Losing megalin/cubilin-mediated retrieval sends filtered vitamin D-binding
    protein, 25(OH)-vitamin D3 and PTH into the urine. Two opposing effects
    follow. Reduced endocytosis of luminal PTH raises the concentration seen by
    apical PTH receptors, which should drive 1-alpha-hydroxylation of
    25(OH)-vitamin D3 to the active hormone and so increase intestinal calcium
    absorption; at the same time the precursor itself is being lost in the
    urine. The balance of those two effects is the current explanation for why
    serum 1,25(OH)2-vitamin D3 is variable between patients and for why
    hypercalciuria is present in most but not all of them. The mechanism is
    inferred from the mouse model and from the known cargo of the receptor
    complex rather than demonstrated directly in patients.
  cell_types:
  - preferred_term: kidney proximal convoluted tubule epithelial cell
    term:
      id: CL:1000838
      label: kidney proximal convoluted tubule epithelial cell
  biological_processes:
  - preferred_term: renal excretion of vitamin D metabolites and PTH
    term:
      id: GO:0007588
      label: excretion
    modifier: DYSREGULATED
  evidence:
  - reference: PMID:11099045
    reference_title: "ClC-5 Cl- -channel disruption impairs endocytosis in a mouse model for Dent's disease."
    supports: SUPPORT
    evidence_source: MODEL_ORGANISM
    snippet: "This may be caused by an increased stimulation of luminal parathyroid hormone (PTH) receptors owing to the observed decreased tubular endocytosis of PTH. The rise in luminal PTH concentration should also stimulate the hydroxylation of 25(OH) vitamin D3 to the active hormone. However, this is counteracted by a urinary loss of the precursor 25(OH) vitamin D3."
    explanation: Sets out the two opposing vitamin D effects that this node represents, as observed in the Clcn5 knockout mouse.
  downstream:
  - target: Urinary Calcium Supersaturation
    causal_link_type: INDIRECT_KNOWN_INTERMEDIATES
    intermediate_mechanisms:
    - Net increase in active 1,25(OH)2-vitamin D3 raising intestinal calcium absorption
    - Increased filtered calcium load presented to the tubule
    evidence:
    - reference: PMID:11099045
      reference_title: "ClC-5 Cl- -channel disruption impairs endocytosis in a mouse model for Dent's disease."
      supports: SUPPORT
      evidence_source: MODEL_ORGANISM
      snippet: "The balance between these opposing effects, both of which are secondary to the defect in proximal tubular endocytosis, probably determines whether there will be hypercalciuria and kidney stones."
      explanation: The authors themselves mark this link as probable rather than established, which is why the edge is indirect.
  - target: Hypercalciuria
    causal_link_type: INDIRECT_UNKNOWN_INTERMEDIATES

- name: Generalized Proximal Tubular Solute Wasting
  biological_scale: TISSUE
  description: >
    Beyond protein, the proximal tubule of a Dent disease patient leaks a
    variable combination of amino acids, phosphate, glucose, urate and
    potassium, and urinary acidification may be impaired. The picture is an
    incomplete Fanconi syndrome rather than the full generalised defect: the
    guideline records it in 25-65% of Dent disease 1 and 30-70% of Dent disease
    2 patients. Sustained phosphate wasting is what produces the bone disease.
  cell_types:
  - preferred_term: kidney proximal convoluted tubule epithelial cell
    term:
      id: CL:1000838
      label: kidney proximal convoluted tubule epithelial cell
  locations:
  - preferred_term: renal proximal tubule
    term:
      id: UBERON:0004134
      label: proximal tubule
  biological_processes:
  - preferred_term: phosphate ion transport
    term:
      id: GO:0006817
      label: phosphate ion transport
    modifier: DECREASED
  - preferred_term: renal solute excretion
    term:
      id: GO:0007588
      label: excretion
    modifier: DYSREGULATED
  evidence:
  - reference: PMID:20946626
    reference_title: "Dent's disease."
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "Dent's disease may also be associated with aminoaciduria, phosphaturia, glycosuria, uricosuria, kaliuresis, and impaired urinary acidification, and is often complicated by rickets or osteomalacia"
    explanation: Enumerates the solutes wasted at this node and names the bone consequence of the phosphate leak.
  downstream:
  - target: Hypophosphatemia
    causal_link_type: DIRECT
  - target: Aminoaciduria
    causal_link_type: DIRECT
  - target: Glycosuria
    causal_link_type: DIRECT
  - target: Hypokalemia
    causal_link_type: DIRECT
  - target: Rickets
    causal_link_type: INDIRECT_KNOWN_INTERMEDIATES
    intermediate_mechanisms:
    - Prolonged hypophosphataemia causing bone demineralization
    evidence:
    - reference: PMID:39794284
      reference_title: "Dent disease: clinical practice recommendations."
      supports: SUPPORT
      evidence_source: OTHER
      snippet: "Prolonged hypophosphataemia may cause bone demineralization manifesting as rickets in children or osteomalacia in adults."
      explanation: Names the intermediate between the tubular phosphate leak and the skeletal phenotype.

- name: Urinary Calcium Supersaturation
  biological_scale: ORGANISM
  conforms_to: "nephrolithiasis_crystal_nucleation#Urinary Supersaturation"
  description: >
    Hypercalciuria raises the relative supersaturation of the urine with
    respect to calcium oxalate and calcium phosphate, which is the
    thermodynamic driving force for stone formation. In Dent disease the
    lithogenic solute is calcium; citrate excretion is lower than in other
    forms of renal Fanconi syndrome, removing some of the usual inhibitory
    capacity. This node is the disease-specific substitution into the
    nephrolithiasis module's supersaturation trigger.
  biological_processes:
  - preferred_term: renal calcium excretion
    term:
      id: GO:0007588
      label: excretion
    modifier: DYSREGULATED
  - preferred_term: calcium ion transport
    term:
      id: GO:0006816
      label: calcium ion transport
    modifier: DYSREGULATED
  evidence:
  - reference: PMID:12444212
    reference_title: "Responsiveness of hypercalciuria to thiazide in Dent's disease."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Hypercalciuria is the major risk factor promoting stone formation in Dent's disease, also known as X-linked recessive nephrolithiasis, but the effects of diuretics on calcium excretion and other stone risk factors in this disease are unknown."
    explanation: Identifies calcium as the lithogenic solute of this disease, which is the substitution the module expects.
  - reference: PMID:12444212
    reference_title: "Responsiveness of hypercalciuria to thiazide in Dent's disease."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "In patients with Dent's disease during chlorthalidone therapy, the supersaturation ratios for calcium oxalate and calcium phosphate fell by 25% and 35%, respectively."
    explanation: Measures calcium oxalate and calcium phosphate supersaturation directly in Dent disease patients, grounding this node in human data.
  - reference: PMID:39794284
    reference_title: "Dent disease: clinical practice recommendations."
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "citrate excretion in DD is lower compared with other forms of renal Fanconi syndrome"
    explanation: Records the reduced inhibitory capacity that accompanies the raised calcium load in this disease.
  downstream:
  - target: Calcium Crystal Nucleation and Retention
    causal_link_type: DIRECT

- name: Calcium Crystal Nucleation and Retention
  biological_scale: TISSUE
  conforms_to: "nephrolithiasis_crystal_nucleation#Crystal Nucleation and Growth"
  description: >
    Supersaturated urine nucleates calcium crystals which must then be retained
    rather than flushed out for nephrocalcinosis or a stone to form. In Dent
    disease retention appears to carry independent weight, because
    nephrolithiasis and nephrocalcinosis have been reported in patients without
    hypercalciuria, which has been attributed to impaired clearance of
    microcrystals from the collecting duct epithelial surface. Nephrocalcinosis
    is typically detectable from childhood while discrete stones appear later.
  cell_types:
  - preferred_term: renal tubular epithelial cell
    term:
      id: CL:0002518
      label: kidney epithelial cell
  locations:
  - preferred_term: kidney
    term:
      id: UBERON:0002113
      label: kidney
  biological_processes:
  - preferred_term: crystal-epithelial cell adhesion
    term:
      id: GO:0007155
      label: cell adhesion
  evidence:
  - reference: PMID:39794284
    reference_title: "Dent disease: clinical practice recommendations."
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "which might be explained by impaired clearance of microcrystals from the surface of collecting duct cells, as demonstrated in vitro"
    explanation: Supports treating crystal retention as a step with its own weight in this disease rather than a passive consequence of supersaturation.
  - reference: PMID:39794284
    reference_title: "Dent disease: clinical practice recommendations."
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "Nephrocalcinosis is often detectable from childhood while kidney stones manifest at a later age"
    explanation: Gives the temporal ordering of the two mineral outcomes downstream of this node.
  downstream:
  - target: Nephrocalcinosis
    causal_link_type: DIRECT
  - target: Nephrolithiasis
    causal_link_type: DIRECT

- name: Tubulointerstitial Fibrosis and Progressive Nephron Loss
  biological_scale: TISSUE
  description: >
    How a proximal tubulopathy becomes progressive chronic kidney disease is
    the least resolved part of the mechanism and the guideline says so plainly.
    The proposed route is that early adaptive changes in proximal tubular cells
    - proliferation, dedifferentiation, autophagy, metabolic adaptation -
    become maladaptive, promoting inflammation and tubulointerstitial fibrosis,
    with the tubular protein load itself contributing by stressing distal
    nephron segments. Biopsy series show focal interstitial fibrosis,
    interstitial lymphocytic infiltration and tubular damage alongside the
    glomerular lesions, and a knock-in mouse carrying a representative
    pathogenic Clcn5 missense variant develops fibrosis and apoptosis with age.
  cell_types:
  - preferred_term: kidney proximal convoluted tubule epithelial cell
    term:
      id: CL:1000838
      label: kidney proximal convoluted tubule epithelial cell
  locations:
  - preferred_term: kidney
    term:
      id: UBERON:0002113
      label: kidney
  biological_processes:
  - preferred_term: extracellular matrix organization
    term:
      id: GO:0030198
      label: extracellular matrix organization
    modifier: DYSREGULATED
  - preferred_term: inflammatory response
    term:
      id: GO:0006954
      label: inflammatory response
    modifier: INCREASED
  evidence:
  - reference: PMID:39794284
    reference_title: "Dent disease: clinical practice recommendations."
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "The mechanisms behind the transition from proximal tubular dysfunction to progressive chronic kidney disease (CKD) in DD remain to be deciphered."
    explanation: Records explicitly that this step of the causal chain is unresolved, which the node description must not overstate.
  - reference: PMID:39794284
    reference_title: "Dent disease: clinical practice recommendations."
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "Early changes in proximal tubular cells, including proliferation, dedifferentiation, autophagy, and metabolic adaptation, may become maladaptive and promote inflammation and progression of tubulointerstitial fibrosis by various mechanisms"
    explanation: States the proposed, explicitly hypothetical route from tubular injury to fibrosis.
  - reference: PMID:27697782
    reference_title: "Glomerular Pathology in Dent Disease and Its Association with Kidney Function."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "focal interstitial fibrosis in 60% (18 of 30), interstitial lymphocytic infiltration in 53% (16 of 30), and tubular damage in 70% (21 of 30)"
    explanation: Human biopsy series quantifying the interstitial and tubular lesions this node describes.
  - reference: PMID:39019097
    reference_title: "A novel transgenic mouse model highlights molecular disruptions involved in the pathogenesis of Dent disease 1."
    supports: SUPPORT
    evidence_source: MODEL_ORGANISM
    snippet: "With ageing, KI mice showed increased renal fibrosis, apoptosis and major changes in cell metabolic functions as already suggested in previous DD models."
    explanation: Model-organism evidence that fibrosis accumulates with age downstream of a pathogenic Clcn5 missense variant.
  downstream:
  - target: Chronic kidney disease
    causal_link_type: DIRECT
phenotypes:
- name: Low-molecular-weight proteinuria
  category: Renal
  frequency: OBLIGATE
  diagnostic: true
  description: >
    The defining and obligate finding, present in effectively every affected
    male and in most obligate female carriers. Retinol-binding protein has the
    best reported sensitivity and specificity for the tubular origin;
    beta-2-microglobulin is widely used but degrades in acidic or
    bacterially contaminated urine. An alpha-1-microglobulin/creatinine ratio
    above 120 mg/g separates Dent disease from glomerular disease with high
    accuracy.
  phenotype_term:
    preferred_term: Low-molecular-weight proteinuria
    term:
      id: HP:0003126
      label: Low-molecular-weight proteinuria
  evidence:
  - reference: PMID:39794284
    reference_title: "Dent disease: clinical practice recommendations."
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "Low-molecular-weight proteinuria | 100 | 100"
    explanation: Guideline frequency table records low-molecular-weight proteinuria in 100% of both Dent disease 1 and Dent disease 2 patients.
  - reference: PMID:20946626
    reference_title: "Dent's disease."
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "Low-molecular-weight (LMW) proteinuria represents the most consistent manifestation of Dent's disease, detected in almost all affected males and obligate female carriers."
    explanation: Independent review confirms this is the most consistent finding and extends it to obligate carriers.
  - reference: PMID:39794284
    reference_title: "Dent disease: clinical practice recommendations."
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "An α1-microglobulin/creatinine ratio above 120 mg/g (13.6 mg/mmol) has high accuracy in separating DD from glomerular disease"
    explanation: Gives the quantitative threshold that makes this phenotype diagnostically decisive.

- name: Hypercalciuria
  category: Renal
  frequency: FREQUENT
  diagnostic: true
  description: >
    The second defining feature, though not mandatory for diagnosis. Its
    detection is strongly age-dependent, found in 61-73% of children and young
    adults but only 14-19% of adults, so a normal adult calcium excretion does
    not exclude the disease.
  phenotype_term:
    preferred_term: Hypercalciuria
    term:
      id: HP:0002150
      label: Hypercalciuria
  evidence:
  - reference: PMID:39794284
    reference_title: "Dent disease: clinical practice recommendations."
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "Hypercalciuria | 44–90 | 80–100"
    explanation: Guideline frequency table gives the reported ranges for Dent disease 1 and Dent disease 2.
  - reference: PMID:39794284
    reference_title: "Dent disease: clinical practice recommendations."
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "While proteinuria is present during the entire course of the disease, hypercalciuria is detected in 61%–73% of children and young adults compared with 14%–19% of adults"
    explanation: Documents the age dependence that makes hypercalciuria an unreliable adult diagnostic criterion.
  - reference: PMID:39794284
    reference_title: "Dent disease: clinical practice recommendations."
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "Although hypercalciuria is the second most frequent finding in DD, its absence does not exclude a diagnosis of DD."
    explanation: States that this phenotype, while characteristic, is not obligate.

- name: Nephrocalcinosis
  category: Renal
  frequency: FREQUENT
  description: >
    Diffuse renal calcification, usually detectable on ultrasound from
    childhood and substantially commoner in Dent disease 1 than Dent disease 2.
  phenotype_term:
    preferred_term: Nephrocalcinosis
    term:
      id: HP:0000121
      label: Nephrocalcinosis
  evidence:
  - reference: PMID:39794284
    reference_title: "Dent disease: clinical practice recommendations."
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "Nephrocalcinosis | 40–75 | 10–40"
    explanation: Guideline frequency table quantifies nephrocalcinosis separately for the two genetic subtypes.

- name: Nephrolithiasis
  category: Renal
  frequency: FREQUENT
  description: >
    Discrete calcium stones, manifesting later than nephrocalcinosis. Stone
    disease is prominent enough historically that the disorder was originally
    described as X-linked recessive nephrolithiasis.
  phenotype_term:
    preferred_term: Nephrolithiasis
    term:
      id: HP:0000787
      label: Nephrolithiasis
  evidence:
  - reference: PMID:39794284
    reference_title: "Dent disease: clinical practice recommendations."
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "Nephrolithiasis | 20–40 | 10–15"
    explanation: Guideline frequency table quantifies stone disease in both genetic subtypes.
  - reference: PMID:20946626
    reference_title: "Dent's disease."
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "Dent's disease is a renal tubular disorder characterized by manifestations of proximal tubule dysfunction, including low-molecular-weight proteinuria, hypercalciuria, nephrolithiasis, nephrocalcinosis, and progressive renal failure."
    explanation: Establishes nephrolithiasis as a defining manifestation of the disorder.

- name: Chronic kidney disease
  category: Renal
  frequency: FREQUENT
  description: >
    Progressive loss of kidney function is the outcome that dominates
    prognosis. Kidney failure appears between the third and fifth decades in
    30-80% of affected males, with a series reporting four of ten patients aged
    30-40 years, three of nine aged 40-50 and three of four aged 50-60 already
    in kidney failure. Progression is variable even within one family.
  phenotype_term:
    preferred_term: Chronic kidney disease
    term:
      id: HP:0012622
      label: Chronic kidney disease
    clinical_course: PROGRESSIVE
  evidence:
  - reference: PMID:39794284
    reference_title: "Dent disease: clinical practice recommendations."
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "Dent disease is a rare X-linked tubulopathy that is characterized by low-molecular-weight proteinuria associated with hypercalciuria, which may lead to nephrolithiasis, nephrocalcinosis, and kidney failure between the third and fifth decades of life in 30%-80% of affected males."
    explanation: Gives the timing and the proportion of affected males reaching kidney failure.
  - reference: PMID:39794284
    reference_title: "Dent disease: clinical practice recommendations."
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "Four out of ten patients aged 30–40 years, three out of nine aged 40–50 years, and three out of four aged 50–60 years had kidney failure"
    explanation: Provides the age-stratified counts behind the aggregate kidney-failure figure.
  - reference: PMID:39794284
    reference_title: "Dent disease: clinical practice recommendations."
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "Also, the course of kidney failure may be variable within the same family"
    explanation: Records intrafamilial variability, which constrains how far prognosis can be individualised from genotype.

  - reference: PMID:22876375
    reference_title: "Dent Disease."
    supports: SUPPORT
    quote_role: REVIEW_SYNTHESIS
    evidence_source: OTHER
    snippet: "Thirty to 80% of affected males develop end-stage renal disease (ESRD) between ages 30 and 50 years; in some instances ESRD does not develop until the sixth decade of life or later."
    explanation: GeneReviews gives both the affected fraction and the age window this phenotype's description
      states, including the late-onset tail.
- name: Focal segmental glomerulosclerosis
  category: Renal
  frequency: FREQUENT
  description: >
    Glomerular lesions are found on the great majority of Dent disease
    biopsies, with focal global glomerulosclerosis in 83% and mild segmental
    foot-process effacement in 57% of a 30-patient international biopsy series.
    Their presence is why the disease is so often first labelled as
    steroid-resistant nephrotic syndrome or idiopathic FSGS. Higher degrees of
    sclerosis, effacement and interstitial inflammation track with lower eGFR,
    and foot-process effacement with a steeper annual decline.
  phenotype_term:
    preferred_term: Focal segmental glomerulosclerosis
    term:
      id: HP:0000097
      label: Focal segmental glomerulosclerosis
  evidence:
  - reference: PMID:27697782
    reference_title: "Glomerular Pathology in Dent Disease and Its Association with Kidney Function."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Prominent histologic findings included focal global glomerulosclerosis in 83% (25 of 30; affecting 16%±19% glomeruli), mild segmental foot process effacement in 57% (13 of 23)"
    explanation: International biopsy series quantifying the glomerular lesion in Dent disease.
  - reference: PMID:27697782
    reference_title: "Glomerular Pathology in Dent Disease and Its Association with Kidney Function."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Higher percentages of globally sclerotic glomeruli, foot process effacement, and interstitial inflammation were associated with lower eGFR at biopsy, whereas foot process effacement was associated with steeper annual eGFR decline."
    explanation: Links the glomerular lesion to kidney function and rate of decline, supporting its prognostic weight.
  - reference: PMID:27697782
    reference_title: "Glomerular Pathology in Dent Disease and Its Association with Kidney Function."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Dent disease should be suspected in boys and men who have unexplained proteinuria with focal global glomerulosclerosis and segmental foot process effacement on renal biopsy."
    explanation: States the diagnostic inversion this phenotype creates, which is the practical reason to curate it.

- name: Hypophosphatemia
  category: Metabolic
  frequency: OCCASIONAL
  description: >
    Usually mild to moderate, arising from proximal phosphate wasting.
    Prolonged hypophosphataemia is the route to the skeletal phenotype,
    although the guideline notes no clear correlation between its depth and the
    presence of rickets.
  phenotype_term:
    preferred_term: Hypophosphatemia
    term:
      id: HP:0002148
      label: Hypophosphatemia
  evidence:
  - reference: PMID:39794284
    reference_title: "Dent disease: clinical practice recommendations."
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "Hypophosphatemia | 15–35 | 10–20"
    explanation: Guideline frequency table quantifies hypophosphatemia in both genetic subtypes.
  - reference: PMID:39794284
    reference_title: "Dent disease: clinical practice recommendations."
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "As hypophosphataemia in DD is usually mild or moderate, it can be corrected with increased dietary phosphate and/or oral supplementation."
    explanation: Characterises the severity of the phosphate deficit and its management.

- name: Aminoaciduria
  category: Metabolic
  frequency: FREQUENT
  description: >
    Generalised urinary amino acid loss as part of the incomplete Fanconi
    picture; commoner in Dent disease 2 than in Dent disease 1.
  phenotype_term:
    preferred_term: Aminoaciduria
    term:
      id: HP:0003355
      label: Aminoaciduria
  evidence:
  - reference: PMID:39794284
    reference_title: "Dent disease: clinical practice recommendations."
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "Aminoaciduria | 20–50 | 40–70"
    explanation: Guideline frequency table quantifies aminoaciduria in both genetic subtypes.

- name: Glycosuria
  category: Metabolic
  frequency: OCCASIONAL
  description: >
    Glucose in the urine at normal blood glucose, from proximal tubular
    reabsorptive failure rather than from diabetes.
  phenotype_term:
    preferred_term: Glycosuria
    term:
      id: HP:0003076
      label: Glycosuria
  evidence:
  - reference: PMID:39794284
    reference_title: "Dent disease: clinical practice recommendations."
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "Glucosuria | 20–40 | 5–15"
    explanation: Guideline frequency table quantifies glycosuria in both genetic subtypes.

- name: Hypokalemia
  category: Metabolic
  frequency: OCCASIONAL
  description: >
    Low serum potassium from renal potassium wasting; also a reason the
    guideline advises against routine thiazide use, which aggravates it.
  phenotype_term:
    preferred_term: Hypokalemia
    term:
      id: HP:0002900
      label: Hypokalemia
  evidence:
  - reference: PMID:39794284
    reference_title: "Dent disease: clinical practice recommendations."
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "Hypokalaemia | 20–40 | 10–20"
    explanation: Guideline frequency table quantifies hypokalaemia in both genetic subtypes.

- name: Rickets
  category: Skeletal
  frequency: OCCASIONAL
  description: >
    Vitamin D-resistant rickets in children, with osteomalacia the adult
    counterpart. Active vitamin D should not be used to treat it, because
    1,25(OH)2 vitamin D is already inherently elevated and giving more worsens
    the hypercalciuria.
  phenotype_term:
    preferred_term: Rickets
    term:
      id: HP:0002748
      label: Rickets
  evidence:
  - reference: PMID:39794284
    reference_title: "Dent disease: clinical practice recommendations."
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "Rickets | 5–33 | 10–20"
    explanation: Guideline frequency table quantifies rickets in both genetic subtypes.
  - reference: PMID:39794284
    reference_title: "Dent disease: clinical practice recommendations."
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "Few data on bone health in DD have been reported, except that some patients present with vitamin D-resistant rickets"
    explanation: Characterises the rickets as vitamin D-resistant, which drives the treatment caution recorded here.

- name: Osteomalacia
  category: Skeletal
  frequency: OCCASIONAL
  description: >
    The adult form of the same phosphate-wasting bone disease, arising from
    prolonged hypophosphataemia.
  phenotype_term:
    preferred_term: Osteomalacia
    term:
      id: HP:0002749
      label: Osteomalacia
  evidence:
  - reference: PMID:39794284
    reference_title: "Dent disease: clinical practice recommendations."
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "Prolonged hypophosphataemia may cause bone demineralization manifesting as rickets in children or osteomalacia in adults."
    explanation: Establishes osteomalacia as the adult skeletal manifestation of the tubular phosphate leak.

- name: Hematuria
  category: Renal
  frequency: OCCASIONAL
  description: >
    Usually microscopic, and one of the presenting findings that leads to
    investigation. It is one of the accepted supporting features of the
    clinical case definition.
  phenotype_term:
    preferred_term: Hematuria
    term:
      id: HP:0000790
      label: Hematuria
  evidence:
  - reference: PMID:20946626
    reference_title: "Dent's disease."
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "In addition, these patients may also have nephrocalcinosis, nephrolithiasis, haematuria, hypophosphataemia and/or renal insufficiency."
    explanation: Lists haematuria among the manifestations of Dent disease.
  - reference: PMID:34680992
    reference_title: "Genotype Phenotype Correlation in Dent Disease 2 and Review of the Literature: OCRL Gene Pleiotropism or Extreme Phenotypic Variability of Lowe Syndrome?"
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Nephrocalcinosis was identified in 42% of the patients, nephrolithiasis in 32%, and hematuria in 59%."
    explanation: Quantifies haematuria in the largest Dent disease 2 cohort.

- name: Growth delay
  category: Growth
  subtype: DD2
  frequency: FREQUENT
  description: >
    Short stature is much commoner in Dent disease 2 (60-80%) than in Dent
    disease 1 (10-20%), and is one of the mild extrarenal signs that
    distinguishes the OCRL-related form.
  phenotype_term:
    preferred_term: Growth delay
    term:
      id: HP:0001510
      label: Growth delay
  evidence:
  - reference: PMID:39794284
    reference_title: "Dent disease: clinical practice recommendations."
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "Growth retardation | 10–20 | 60–80"
    explanation: Guideline frequency table shows the marked excess of growth retardation in Dent disease 2.

- name: Elevated circulating creatine kinase concentration
  category: Laboratory
  subtype: DD2
  frequency: VERY_FREQUENT
  description: >
    Raised CPK, and often AST and LDH, is the single most discriminating
    extrarenal marker of Dent disease 2, reported in 80-90% of patients against
    5-20% in Dent disease 1. Muscle findings are the commonest extrarenal
    feature in the largest DD2 series.
  phenotype_term:
    preferred_term: Elevated circulating creatine kinase activity
    term:
      id: HP:0003236
      label: Elevated circulating creatine kinase activity
  evidence:
  - reference: PMID:39794284
    reference_title: "Dent disease: clinical practice recommendations."
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "Elevated serum levels of CPK, ASAT and/or LDH | 5–20 | 80–90"
    explanation: Guideline frequency table gives the strong subtype discrimination for raised muscle enzymes.
  - reference: PMID:34680992
    reference_title: "Genotype Phenotype Correlation in Dent Disease 2 and Review of the Literature: OCRL Gene Pleiotropism or Extreme Phenotypic Variability of Lowe Syndrome?"
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Muscle findings are the most common ES (52%), while ocular findings are less common (11%)."
    explanation: Largest Dent disease 2 cohort confirms muscle involvement as the dominant extrarenal finding.

- name: Intellectual disability
  category: Neurologic
  subtype: DD2
  frequency: OCCASIONAL
  description: >
    Mild intellectual impairment occurs in a quarter to a third of Dent disease
    2 patients and is uncommon in Dent disease 1. It is mild and does not
    progress towards the Lowe syndrome picture over time.
  phenotype_term:
    preferred_term: Intellectual disability
    term:
      id: HP:0001249
      label: Intellectual disability
    severity: MILD
  evidence:
  - reference: PMID:39794284
    reference_title: "Dent disease: clinical practice recommendations."
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "Intellectual impairment | 0–9 | 25–30"
    explanation: Guideline frequency table separates intellectual impairment between the two genetic subtypes.
  - reference: PMID:20946626
    reference_title: "Dent's disease."
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "Moreover, the patients with Dent disease 2 and mild intellectual deficit were adults, who had not, over time, developed more overt features of Lowe's syndrome"
    explanation: Establishes that the intellectual phenotype stays mild and does not evolve into Lowe syndrome, which underpins the lump/split decision.

- name: Cataract
  category: Ophthalmologic
  subtype: DD2
  frequency: OCCASIONAL
  description: >
    Punctate, non-dense lens opacities occur in a small minority of Dent
    disease 2 patients. This contrasts sharply with Lowe syndrome, where dense
    bilateral congenital cataract is obligate, and is the clearest single
    clinical discriminator between the two OCRL phenotypes.
  phenotype_term:
    preferred_term: Punctate cataract
    term:
      id: HP:0007648
      label: Punctate cataract
  evidence:
  - reference: PMID:39794284
    reference_title: "Dent disease: clinical practice recommendations."
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "Congenital cataract | Very rare | 7–10"
    explanation: Guideline frequency table shows cataract is rare in Dent disease 1 and uncommon even in Dent disease 2.
  - reference: PMID:20946626
    reference_title: "Dent's disease."
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "although it is important to note that none of these had the severe cataracts or intellectual deficit that is typically found in patients with Lowe syndrome"
    explanation: Contrasts the ocular phenotype with Lowe syndrome, supporting the separation of the two entries.
  - reference: PMID:22876375
    reference_title: "Dent Disease."
    supports: SUPPORT
    quote_role: REVIEW_SYNTHESIS
    evidence_source: OTHER
    snippet: "Males with Dent disease 2 (caused by pathogenic variants in OCRL) may also have mild intellectual disability, cataracts, and/or elevated muscle enzymes."
    explanation: GeneReviews restricts cataract to the Dent disease 2 subtype, which is what the DD2 subtype
      scoping on this phenotype records.
diagnosis:
- name: Establishing the diagnosis in a male proband
  presence: PRESENT
  description: >
    The diagnosis rests on the typical tubular findings together with an
    X-linked family history and a pathogenic variant in CLCN5 or OCRL, which is
    also what separates the two genetic forms from each other.
  evidence:
  - reference: PMID:22876375
    reference_title: "Dent Disease."
    supports: SUPPORT
    quote_role: REVIEW_SYNTHESIS
    evidence_source: OTHER
    snippet: "The diagnosis is established in a male proband with the typical clinical findings and a family history consistent with X-linked inheritance who has a pathogenic variant in either CLCN5 (known as Dent disease 1) or in OCRL (known as Dent disease 2)."
    explanation: The GeneReviews diagnostic statement, naming both the clinical picture and the confirmatory
      molecular test.
  - reference: PMID:22876375
    reference_title: "Dent Disease."
    supports: SUPPORT
    quote_role: REVIEW_SYNTHESIS
    evidence_source: OTHER
    snippet: "Heterozygous females are most likely to be identified by familial molecular genetic testing related to a male proband."
    explanation: States how carrier females come to attention, which is why the entry does not model a
      female-proband diagnostic route.
- name: Surveillance of kidney function and calcium excretion
  presence: PRESENT
  description: >
    Annual monitoring of urinary calcium excretion, glomerular filtration rate
    and the CKD staging parameters, increasing in frequency once chronic kidney
    disease is established.
  evidence:
  - reference: PMID:22876375
    reference_title: "Dent Disease."
    supports: SUPPORT
    quote_role: REVIEW_SYNTHESIS
    evidence_source: OTHER
    snippet: "Monitor at least annually urinary calcium excretion, renal function (glomerular filtration rate), and the parameters used to stage CKD"
    explanation: The GeneReviews surveillance schedule, which is the management action that tracks the two
      mechanisms this entry models as driving progression.
treatments:
- name: Potassium Citrate
  description: >
    Alkalinising citrate is the treatment the 2025 ERA/ESPN recommendations
    place first for stone and nephrocalcinosis risk, on a weak recommendation
    grade because no human trial in Dent disease exists. The case rests on a
    high-citrate diet slowing CKD in Clcn5 knockout mice, on citrate's proven
    benefit in idiopathic hypercalciuria with hypocitraturia, and on citrate
    excretion in Dent disease being lower than in other Fanconi syndromes.
    Urinary pH needs monitoring, since over-alkalinisation risks calcium
    phosphate precipitation.
  therapeutic_modality: SMALL_MOLECULE
  treatment_term:
    preferred_term: Pharmacotherapy
    term:
      id: NCIT:C15986
      label: Pharmacotherapy
    therapeutic_agent:
    - preferred_term: potassium citrate
      term:
        id: NCIT:C29372
        label: Potassium Citrate
  target_mechanisms:
  - target: Urinary Calcium Supersaturation
    treatment_effect: INHIBITS
    description: >-
      Citrate chelates urinary calcium and raises urinary pH, lowering the
      relative supersaturation that drives calcium crystal nucleation.
    evidence:
    - reference: PMID:39794284
      reference_title: "Dent disease: clinical practice recommendations."
      supports: SUPPORT
      evidence_source: OTHER
      snippet: "Potassium citrate reduces recurrent calcium oxalate nephrolithiasis in patients with idiopathic hypercalciuria and hypocitraturia"
      explanation: The mechanistic rationale is imported from idiopathic hypercalciuria, where the supersaturation effect is established.
  - target: Tubulointerstitial Fibrosis and Progressive Nephron Loss
    treatment_effect: INHIBITS
    description: >-
      In the knockout mouse a high-citrate diet preserved GFR and reduced
      tubular atrophy, interstitial fibrosis and nephrocalcinosis. No human
      equivalent has been done.
    evidence:
    - reference: PMID:16014041
      reference_title: "High citrate diet delays progression of renal insufficiency in the ClC-5 knockout mouse model of Dent's disease."
      supports: SUPPORT
      evidence_source: MODEL_ORGANISM
      snippet: "ClC-5 knockout mice fed a zero citrate diet had significantly increased tubular atrophy, interstitial fibrosis, cystic changes, and nephrocalcinosis compared to ClC-5 knockout mice fed a high citrate diet."
      explanation: Directly measures the fibrosis endpoint this link claims, in the disease's own animal model.
  evidence:
  - reference: PMID:39794284
    reference_title: "Dent disease: clinical practice recommendations."
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "We suggest that citrate treatment may be considered in patients with DD, in particular in the presence of nephrocalcinosis/stone disease (Grade C, weak)."
    explanation: The guideline recommendation itself, with its grade, which is the weakest form of endorsement it issues.
  - reference: PMID:39794284
    reference_title: "Dent disease: clinical practice recommendations."
    supports: NO_EVIDENCE
    evidence_source: OTHER
    snippet: "There have been no human trials studying the efficacy of citrate supplementation in DD."
    explanation: Records that no human efficacy data exist for this treatment in this disease, which is why the grade is weak.
  - reference: PMID:16014041
    reference_title: "High citrate diet delays progression of renal insufficiency in the ClC-5 knockout mouse model of Dent's disease."
    supports: SUPPORT
    evidence_source: MODEL_ORGANISM
    snippet: "High citrate diet preserved renal function and delayed progression of renal disease in ClC-5 knockout mice even in the apparent absence of stone formation."
    explanation: The principal preclinical result behind the recommendation, and the source of its rationale.
  notes: >-
    Reported use is 13-25% of Dent disease patients. As citrate is metabolised
    to bicarbonate it also helps correct metabolic acidosis, but it may
    aggravate alkalosis in patients with significant hyperaldosteronism.

- name: Thiazide Diuretics
  description: >
    Thiazides reliably lower urinary calcium in Dent disease - chlorthalidone
    normalised calcium excretion in seven of eight patients in a randomised
    crossover study, and hydrochlorothiazide cut spot urinary calcium by 42% in
    an open-label trial - yet the 2025 guideline recommends against systematic
    use. The reason is the toxicity, not a failure of effect: hypovolaemia,
    hypokalaemia and hyponatraemia appeared in the same trials, no long-term
    kidney or stone outcome data exist in this disease, and Dent disease 2
    patients are especially prone to dehydration and acute kidney injury on
    thiazides.
  therapeutic_modality: SMALL_MOLECULE
  treatment_term:
    preferred_term: Pharmacotherapy
    term:
      id: NCIT:C15986
      label: Pharmacotherapy
    therapeutic_agent:
    - preferred_term: thiazide diuretic
      term:
        id: NCIT:C49185
        label: Thiazide Diuretic
    - preferred_term: hydrochlorothiazide
      term:
        id: CHEBI:5778
        label: hydrochlorothiazide
    - preferred_term: chlorthalidone
      term:
        id: CHEBI:3654
        label: chlorthalidone
  target_mechanisms:
  - target: Urinary Calcium Supersaturation
    treatment_effect: INHIBITS
    description: >-
      Thiazides act at the distal convoluted tubule, which is unaffected by the
      ClC-5 lesion, so the hypocalciuric response is intact in Dent disease.
    evidence:
    - reference: PMID:12444212
      reference_title: "Responsiveness of hypercalciuria to thiazide in Dent's disease."
      supports: SUPPORT
      evidence_source: HUMAN_CLINICAL
      snippet: "The intact hypocalciuric response to a thiazide diuretic indicates that inactivation of the ClC-5 chloride channel does not impair calcium transport in the distal convoluted tubule and indicates that thiazides should be useful in reducing the risk of kidney stone recurrence in patients with Dent's disease."
      explanation: Establishes both that the drug target is intact in this disease and that supersaturation falls in response.
  evidence:
  - reference: PMID:12444212
    reference_title: "Responsiveness of hypercalciuria to thiazide in Dent's disease."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "With chlorthalidone, calcium excretion fell to normal (<4.0 mg/kg per d) in all but one patient in each group."
    explanation: Randomised crossover data quantifying the hypocalciuric effect in genetically confirmed Dent disease.
  - reference: PMID:18976849
    reference_title: "Effect of hydrochlorothiazide on urinary calcium excretion in dent disease: an uncontrolled trial."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "The greatest HCTZ doses decreased spot urinary calcium excretion by 42% compared with baseline"
    explanation: Independent open-label trial confirming a dose-dependent fall in urinary calcium.
  - reference: PMID:18976849
    reference_title: "Effect of hydrochlorothiazide on urinary calcium excretion in dent disease: an uncontrolled trial."
    supports: REFUTE
    evidence_source: HUMAN_CLINICAL
    snippet: "However, patients developed adverse reactions, including muscle cramps (n = 2), biological (n = 7) or symptomatic hypovolemia (n = 1), hypokalemia (n = 4), and hyponatremia (n = 1), which all corrected after treatment withdrawal."
    explanation: Refutes routine use by documenting that every patient in the trial developed a volume or electrolyte adverse effect.
  - reference: PMID:39794284
    reference_title: "Dent disease: clinical practice recommendations."
    supports: REFUTE
    evidence_source: OTHER
    snippet: "We recommend that thiazide treatment should not be used systematically in DD."
    explanation: The current guideline position against routine use, despite the demonstrated biochemical effect.
  - reference: PMID:39794284
    reference_title: "Dent disease: clinical practice recommendations."
    supports: REFUTE
    evidence_source: OTHER
    snippet: "DD2 patients are even more susceptible to severe dehydration and acute kidney injury when treated with thiazides"
    explanation: Records a subtype-specific harm that sharpens the recommendation against thiazides in Dent disease 2.

  - reference: PMID:22876375
    reference_title: "Dent Disease."
    supports: SUPPORT
    quote_role: REVIEW_SYNTHESIS
    evidence_source: OTHER
    snippet: "Although thiazide diuretics can decrease urinary calcium excretion in boys with Dent disease, side effects limit their use."
    explanation: GeneReviews states both the effect and the tolerability limit that keeps thiazides a qualified
      rather than a first-line option.
- name: Phosphate Supplementation for Rickets and Osteomalacia
  description: >
    Oral phosphate salts, titrated on serum alkaline phosphatase and on
    radiographic improvement, for patients with hypophosphataemia and signs of
    rickets or osteomalacia. Crucially, active vitamin D must not be added in
    the way it would be for X-linked hypophosphataemic rickets, because
    1,25(OH)2 vitamin D is already inherently elevated in Dent disease and
    raising it further worsens the hypercalciuria.
  therapeutic_modality: SMALL_MOLECULE
  treatment_term:
    preferred_term: Pharmacotherapy
    term:
      id: NCIT:C15986
      label: Pharmacotherapy
    therapeutic_agent:
    - preferred_term: phosphate
      term:
        id: CHEBI:26020
        label: phosphate
  target_mechanisms:
  - target: Hypophosphatemia
    treatment_effect: RESTORES
    description: >-
      Replaces the phosphate lost through the proximal tubule, correcting the
      substrate deficit that drives bone demineralization.
    evidence:
    - reference: PMID:39794284
      reference_title: "Dent disease: clinical practice recommendations."
      supports: SUPPORT
      evidence_source: OTHER
      snippet: "As hypophosphataemia in DD is usually mild or moderate, it can be corrected with increased dietary phosphate and/or oral supplementation."
      explanation: States that supplementation corrects the deficit this link targets.
  evidence:
  - reference: PMID:39794284
    reference_title: "Dent disease: clinical practice recommendations."
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "We suggest treating patients with DD using phosphate salts in case of hypophosphatemia and signs of rickets of osteomalacia (Grade X, weak)."
    explanation: The guideline recommendation for this treatment, with its grade.
  - reference: PMID:39794284
    reference_title: "Dent disease: clinical practice recommendations."
    supports: REFUTE
    evidence_source: OTHER
    snippet: "In contrast to hypophosphataemic rickets, active vitamin D should not be given because of inherently elevated 1.25(OH)2 vitamin D and potential worsening of hypercalciuria."
    explanation: Refutes the transfer of the standard hypophosphataemic-rickets regimen into this disease, which is the key prescribing trap.

- name: Vitamin A Supplementation
  description: >
    Retinol-binding protein is one of the low-molecular-weight proteins lost in
    the urine, so vitamin A deficiency is a foreseeable consequence of the
    endocytic defect. The guideline asks for vigilance for ocular symptoms,
    retinol measurement if they appear, and supplementation if low.
  therapeutic_modality: SMALL_MOLECULE
  treatment_term:
    preferred_term: Pharmacotherapy
    term:
      id: NCIT:C15986
      label: Pharmacotherapy
    therapeutic_agent:
    - preferred_term: vitamin A
      term:
        id: CHEBI:12777
        label: vitamin A
  target_mechanisms:
  - target: Failure of Proximal Tubular Protein Reabsorption
    treatment_effect: BYPASSES
    description: >-
      Supplementation does not repair the endocytic defect; it replaces the
      vitamin whose carrier protein is being lost through it.
    evidence:
    - reference: PMID:39794284
      reference_title: "Dent disease: clinical practice recommendations."
      supports: SUPPORT
      evidence_source: OTHER
      snippet: "Retinol-binding protein is lost as part of low-molecular-weight proteinuria."
      explanation: Names the mechanism by which the vitamin is depleted, which is what the supplement works around.
  evidence:
  - reference: PMID:39794284
    reference_title: "Dent disease: clinical practice recommendations."
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "We recommend vigilance for ocular symptoms of vitamin A deficiency, which should prompt measurement of retinol levels and supplementation if low (Grade B, moderate)."
    explanation: The guideline recommendation covering this treatment.

- name: Growth Hormone for Short Stature
  description: >
    Reserved for growth failure that persists despite adequate metabolic
    control, or for CKD stage 3 or higher. It is a weak recommendation on
    low-grade evidence, and it matters mainly in Dent disease 2, where growth
    retardation affects 60-80% of patients.
  therapeutic_modality: PROTEIN_REPLACEMENT
  treatment_term:
    preferred_term: Pharmacotherapy
    term:
      id: NCIT:C15986
      label: Pharmacotherapy
    therapeutic_agent:
    - preferred_term: somatropin
      term:
        id: NCIT:C837
        label: Somatropin
  target_mechanisms:
  - target: Growth delay
    treatment_effect: MODULATES
    description: >-
      Symptomatic treatment of the growth phenotype, not of any upstream
      mechanism node.
  evidence:
  - reference: PMID:39794284
    reference_title: "Dent disease: clinical practice recommendations."
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "We suggest that treatment with growth hormone (GH) for short stature in patients with DD should only be considered if growth failure persists despite adequate metabolic control or in CKD 3 or higher (Grade D, weak)."
    explanation: The guideline recommendation and its restriction to second-line use.

- name: Kidney Transplantation
  description: >
    Definitive treatment for kidney failure. Because the lesion is in the
    kidney, a transplanted organ is not affected and the disease does not
    recur. Living related donation needs care given that maternal relatives may
    be carriers, and the guideline advises prioritising unrelated donation when
    donor risk cannot be assessed.
  therapeutic_modality: SURGERY
  treatment_term:
    preferred_term: kidney transplantation
    term:
      id: NCIT:C15289
      label: Organ Transplantation
  target_mechanisms:
  - target: Chronic kidney disease
    treatment_effect: RESTORES
    description: >-
      Replaces the failed organ; since the genetic defect is not expressed in
      the graft, the tubulopathy does not return.
    evidence:
    - reference: PMID:39794284
      reference_title: "Dent disease: clinical practice recommendations."
      supports: SUPPORT
      evidence_source: OTHER
      snippet: "The disease does not recur after kidney transplantation."
      explanation: Establishes that transplantation is curative for the renal disease rather than merely supportive.
  evidence:
  - reference: PMID:39794284
    reference_title: "Dent disease: clinical practice recommendations."
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "When risk is difficult to assess, priority should be given to unrelated kidney transplantation"
    explanation: Records the donor-selection caution that follows from X-linked carrier status in the maternal line.

- name: Renin-Angiotensin Blockade
  description: >
    ACE inhibitors and ARBs are used in 11-42% of patients, on the reasoning
    that nephrotic-range proteinuria, glomerulosclerosis, podocyte effacement
    and podocyte expression of CLCN5 and OCRL make this a glomerular disease
    amenable to antiproteinuric therapy. The guideline recommends against
    routine use. Published case series show no fall in proteinuria, which is
    unsurprising given that the proteinuria is tubular rather than glomerular
    in origin, and the hypovolaemia risk is raised in a salt-losing
    tubulopathy. This treatment is curated because it is widely used, not
    because it is endorsed.
  therapeutic_modality: SMALL_MOLECULE
  treatment_term:
    preferred_term: Pharmacotherapy
    term:
      id: NCIT:C15986
      label: Pharmacotherapy
    therapeutic_agent:
    - preferred_term: ACE inhibitor
      term:
        id: NCIT:C247
        label: ACE Inhibitor
    - preferred_term: angiotensin receptor blocker
      term:
        id: NCIT:C66930
        label: Angiotensin II Receptor Antagonist
  target_mechanisms:
  - target: Failure of Proximal Tubular Protein Reabsorption
    treatment_effect: MODULATES
    description: >-
      The intended antiproteinuric target is glomerular, but the proteinuria of
      Dent disease arises at this tubular node, which is the mechanistic reason
      the drugs fail here.
    evidence:
    - reference: PMID:39794284
      reference_title: "Dent disease: clinical practice recommendations."
      supports: REFUTE
      evidence_source: OTHER
      snippet: "which is not unexpected considering the tubular (rather than glomerular) origin of proteinuria in DD"
      explanation: Refutes the antiproteinuric rationale on exactly the mechanistic grounds this pathograph encodes.
  evidence:
  - reference: PMID:39794284
    reference_title: "Dent disease: clinical practice recommendations."
    supports: REFUTE
    evidence_source: OTHER
    snippet: "We suggest that ACE inhibitors (ACEis) or angiotensin receptor blockers (ARBs) should not be used routinely as nephroprotective treatment in patients with DD (Grade C, moderate)."
    explanation: The guideline recommendation against routine renin-angiotensin blockade in this disease.
  - reference: PMID:39794284
    reference_title: "Dent disease: clinical practice recommendations."
    supports: NO_EVIDENCE
    evidence_source: OTHER
    snippet: "However, no studies have addressed the effects of ACEis/ARBs on CKD progression in patients with DD or in animal models."
    explanation: Records the complete absence of outcome data for this widely used treatment.

- name: Genetic Testing and Counselling
  description: >
    Genetic testing of both CLCN5 and OCRL is a strong recommendation for any
    male with isolated persistent low-molecular-weight proteinuria or with
    mixed nephrotic-range proteinuria, because it both confirms the diagnosis
    and separates the two subtypes, which differ in extrarenal surveillance and
    in thiazide tolerance. Testing extends to the mother to establish carrier
    versus de novo status.
  action_category: DIAGNOSTIC
  treatment_term:
    preferred_term: genetic counseling
    term:
      id: NCIT:C15240
      label: Genetic Counseling
  evidence:
  - reference: PMID:39794284
    reference_title: "Dent disease: clinical practice recommendations."
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "We recommend genetic testing to confirm a diagnosis of DD in males and include both CLCN5 and OCRL genes to differentiate between DD1 and DD2 (Grade B, strong)."
    explanation: The strong guideline recommendation for dual-gene testing and the reason for it.
  - reference: PMID:39794284
    reference_title: "Dent disease: clinical practice recommendations."
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "We recommend performing genetic testing in relatives of males with DD as follows: Mothers in order to determine whether the mother is a heterozygous carrier or if the variant is de novo (Grade X, strong)."
    explanation: Extends testing to the maternal line, which is what determines recurrence risk in an X-linked disorder.
  - reference: PMID:22876375
    reference_title: "Dent Disease."
    supports: SUPPORT
    quote_role: REVIEW_SYNTHESIS
    evidence_source: OTHER
    snippet: "Carrier testing for at-risk female relatives and prenatal and preimplantation genetic testing are possible if the pathogenic variant in the family has been identified."
    explanation: GeneReviews states the reproductive testing options this treatment entry offers, which is the
      counselling half of the entry rather than the diagnostic half.
- name: Avoidance of Nephrotoxic Agents
  description: >
    GeneReviews lists avoidance of potential renal toxins among agents and
    circumstances to avoid. In a disease whose defining trajectory is
    progressive loss of kidney function, withholding an avoidable nephrotoxic
    insult is a management action in its own right rather than general caution.
    The named classes are non-steroidal anti-inflammatory drugs, aminoglycoside
    antibiotics and intravenous contrast agents.
  treatment_term:
    preferred_term: avoidance of nephrotoxic agents
    term:
      id: NCIT:C15747
      label: Supportive Care
  target_mechanisms:
  - target: Tubulointerstitial Fibrosis and Progressive Nephron Loss
    treatment_effect: INHIBITS
    description: >-
      Removing an avoidable toxic insult to the proximal tubule acts on the same
      node that the disease itself drives; it does not treat the underlying
      lesion.
  evidence:
  - reference: PMID:22876375
    reference_title: "Dent Disease."
    supports: SUPPORT
    quote_role: REVIEW_SYNTHESIS
    evidence_source: OTHER
    snippet: "Exposure to potential renal toxins (nonsteroidal anti-inflammatory drugs, aminoglycoside antibiotics, and intravenous contrast agents)."
    explanation: The GeneReviews agents-to-avoid list, naming the three specific drug classes.
progression:
- phase: Biochemical onset
  age_range: Childhood, often before 10 years
  notes: >
    Low-molecular-weight proteinuria is present throughout the course and is
    usually the first abnormality, frequently found incidentally on screening
    or during work-up of proteinuria in a boy. Hypercalciuria is detected in
    most children and young adults but in only a minority of adults.
  evidence:
  - reference: PMID:39794284
    reference_title: "Dent disease: clinical practice recommendations."
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "While proteinuria is present during the entire course of the disease, hypercalciuria is detected in 61%–73% of children and young adults compared with 14%–19% of adults"
    explanation: Establishes proteinuria as the constant finding and hypercalciuria as the age-dependent one.
- phase: Mineral and skeletal complications
  age_range: Childhood to early adulthood
  notes: >
    Nephrocalcinosis appears first and is often detectable on childhood
    ultrasound; discrete kidney stones manifest later. Rickets, urolithiasis,
    or an incidentally discovered reduction in kidney function may all be the
    presenting problem.
  evidence:
  - reference: PMID:39794284
    reference_title: "Dent disease: clinical practice recommendations."
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "Nephrocalcinosis is often detectable from childhood while kidney stones manifest at a later age"
    explanation: Gives the temporal ordering of the two mineral complications.
  - reference: PMID:39794284
    reference_title: "Dent disease: clinical practice recommendations."
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "Other subjects may present with rickets or urolithiasis with or without nephrocalcinosis, or simply with previously undiagnosed CKD"
    explanation: Records the alternative presentations at this stage of the course.
- phase: Progressive chronic kidney disease and kidney failure
  age_range: Third to fifth decade
  notes: >
    Kidney failure occurs in 30-80% of affected males between the third and
    fifth decades, with roughly 40% of patients aged 30-40, a third of those
    aged 40-50, and three of four aged 50-60 in one series already in kidney
    failure. Progression is variable within one family, so the genotype does
    not predict the individual trajectory.
  evidence:
  - reference: PMID:39794284
    reference_title: "Dent disease: clinical practice recommendations."
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "Four out of ten patients aged 30–40 years, three out of nine aged 40–50 years, and three out of four aged 50–60 years had kidney failure"
    explanation: Provides the age-stratified kidney-failure counts summarised in this phase.
  - reference: PMID:20946626
    reference_title: "Dent's disease."
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "Progression to end-stage renal failure occurs between the 3rd and 5th decades of life in 30-80% of affected males."
    explanation: Independent review gives the same timing and proportion.
animal_models:
- name: Clcn5 knockout mouse
  species: Mouse
  genotype: Clcn5 null (clcn5 gene disruption, hemizygous male)
  publication: PMID:11099045
  genes:
  - preferred_term: CLCN5
    term:
      id: hgnc:2023
      label: CLCN5
  description: >
    The founding mouse model. Disrupting clcn5 reproduces the proteinuria of
    Dent disease and localises its cause to failed apical proximal tubular
    endocytosis. It also produced the vitamin D / PTH account of hypercalciuria
    that the human literature still uses.
  modeled_mechanisms:
  - target: Megalin and Cubilin Trafficking Failure
    relationship: RECAPITULATES
    fidelity: HIGH
    model_scale: CELLULAR
    description: >-
      Reproduces the endocytic failure of the proximal tubule, both
      receptor-mediated and fluid-phase, with slowed internalization of apical
      transporters.
    limitations: >-
      A complete null, whereas most human disease-causing CLCN5 alleles are
      missense or truncating variants with residual protein handling
      consequences that a null cannot represent.
    readouts:
    - name: Apical proximal tubular endocytosis
      target: Megalin and Cubilin Trafficking Failure
      direction: DECREASED
      interpretation: Direct functional readout of the node in this model.
      evidence:
      - reference: PMID:11099045
        reference_title: "ClC-5 Cl- -channel disruption impairs endocytosis in a mouse model for Dent's disease."
        supports: SUPPORT
        evidence_source: MODEL_ORGANISM
        snippet: "Here we show that disruption of the mouse clcn5 gene causes proteinuria by strongly reducing apical proximal tubular endocytosis."
        explanation: Reports the measurement and its direction.
    evidence:
    - reference: PMID:11099045
      reference_title: "ClC-5 Cl- -channel disruption impairs endocytosis in a mouse model for Dent's disease."
      supports: SUPPORT
      evidence_source: MODEL_ORGANISM
      snippet: "Both receptor-mediated and fluid-phase endocytosis are affected, and the internalization of the apical transporters NaPi-2 and NHE3 is slowed."
      explanation: Supports treating this model as informative for the trafficking node.
  - target: Urinary Loss of Vitamin D-Binding Protein and Parathyroid Hormone
    relationship: RECAPITULATES
    fidelity: MODERATE
    model_scale: ORGANISM
    description: >-
      The model is the origin of the two-opposing-effects account of
      hypercalciuria in this disease.
    limitations: >-
      The authors present the net effect on hypercalciuria as probable rather
      than demonstrated, and the balance has not been measured directly in
      patients.
    evidence:
    - reference: PMID:11099045
      reference_title: "ClC-5 Cl- -channel disruption impairs endocytosis in a mouse model for Dent's disease."
      supports: SUPPORT
      evidence_source: MODEL_ORGANISM
      snippet: "This may be caused by an increased stimulation of luminal parathyroid hormone (PTH) receptors owing to the observed decreased tubular endocytosis of PTH."
      explanation: Reports the PTH handling defect that this node describes.
- name: Clcn5 knock-in missense mouse
  species: Mouse
  genotype: Clcn5 knock-in carrying a representative Dent disease 1 missense variant
  publication: PMID:39019097
  genes:
  - preferred_term: CLCN5
    term:
      id: hgnc:2023
      label: CLCN5
  description: >
    A knock-in model carrying the most representative class of ClC-5 missense
    variant found in patients, rather than a null. It reproduces the Dent
    disease 1 phenotype with disturbed endolysosomal and autophagic function,
    and with age develops fibrosis and apoptosis, so it addresses the
    progression step that the knockout leaves unexplained.
  modeled_mechanisms:
  - target: Tubulointerstitial Fibrosis and Progressive Nephron Loss
    relationship: RECAPITULATES
    fidelity: MODERATE
    model_scale: TISSUE
    description: >-
      With ageing the model accumulates renal fibrosis and apoptosis alongside
      metabolic change, which is the transition from tubulopathy to CKD.
    limitations: >-
      Progression in the mouse is compressed relative to the decades-long human
      course, and the proposed Lipocalin-2/24p3R crosstalk has not been shown in
      patients.
    readouts:
    - name: Renal fibrosis and apoptosis with ageing
      target: Tubulointerstitial Fibrosis and Progressive Nephron Loss
      direction: INCREASED
      interpretation: Histological correlate of the progression node in this model.
      evidence:
      - reference: PMID:39019097
        reference_title: "A novel transgenic mouse model highlights molecular disruptions involved in the pathogenesis of Dent disease 1."
        supports: SUPPORT
        evidence_source: MODEL_ORGANISM
        snippet: "With ageing, KI mice showed increased renal fibrosis, apoptosis and major changes in cell metabolic functions as already suggested in previous DD models."
        explanation: Reports the measurement and its direction.
    evidence:
    - reference: PMID:39019097
      reference_title: "A novel transgenic mouse model highlights molecular disruptions involved in the pathogenesis of Dent disease 1."
      supports: SUPPORT
      evidence_source: MODEL_ORGANISM
      snippet: "These mice showed a characteristic DD type 1 phenotype accompanied by altered endo-lysosomal system and autophagy functions."
      explanation: Supports treating this model as informative for the disease's progressive renal pathology.
- name: Drosophila nephrocyte ClC-c depletion model
  species: Fruit fly
  genotype: Nephrocyte-specific depletion of ClC-c, the Drosophila ortholog of CLCN5
  publication: PMID:41690574
  description: >
    Drosophila nephrocytes share properties with both podocytes and proximal
    tubule cells. Depleting the CLCN5 ortholog reproduces loss of Cubilin from
    the plasma membrane and reduced protein uptake, and revealed a
    secretory-pathway mechanism - Cubilin retained in the endoplasmic reticulum
    with Amnionless reduced - subsequently confirmed in ClC-5 knockout mice.
  modeled_mechanisms:
  - target: Megalin and Cubilin Trafficking Failure
    relationship: RECAPITULATES
    fidelity: MODERATE
    model_scale: CELLULAR
    description: >-
      Reproduces receptor loss from the cell surface and identifies an earlier
      endoplasmic-reticulum export step in the mechanism.
    limitations: >-
      A fly nephrocyte is not a mammalian proximal tubule cell and the fly has
      no megalin ortholog in the mammalian sense, so only the Cubilin/Amnionless
      arm of the receptor complex is modelled. The mammalian confirmation is in
      mice rather than patients.
    readouts:
    - name: Cubilin at the nephrocyte plasma membrane
      target: Megalin and Cubilin Trafficking Failure
      direction: DECREASED
      interpretation: Loss of the receptor from the surface is the defining lesion of this node.
      evidence:
      - reference: PMID:41690574
        reference_title: "A Drosophila model for Dent's disease type 1 revealed impaired endoplasmic reticulum export of Cubilin as pathogenic mechanism."
        supports: SUPPORT
        evidence_source: MODEL_ORGANISM
        snippet: "Upon depletion of ClC-c, the fly ortholog of CLCN5, Cubilin was lost from the plasma membrane of nephrocytes, leading to a strong decrease in albumin uptake and ectopic slit diaphragms."
        explanation: Reports the measurement and its direction.
    evidence:
    - reference: PMID:41690574
      reference_title: "A Drosophila model for Dent's disease type 1 revealed impaired endoplasmic reticulum export of Cubilin as pathogenic mechanism."
      supports: SUPPORT
      evidence_source: MODEL_ORGANISM
      snippet: "Our findings suggest that in addition to its endosomal role ClC-c/ClC-5 acts in the secretory pathway to promote surface trafficking of the Cubilin/Amnionless complex."
      explanation: States the mechanistic conclusion this model contributes to the node.
- name: OCRL-deficient zebrafish
  species: Zebrafish
  genotype: ocrl morphant and mutant lines
  publication: PMID:40778266
  genes:
  - preferred_term: OCRL
    term:
      id: hgnc:8108
      label: OCRL
  description: >
    Zebrafish ocrl models cover both Lowe syndrome and Dent disease 2. They
    show defective pronephric endocytosis, abnormal lysosomal function and
    tubule shortening, which accounts for the low-molecular-weight proteinuria
    of both conditions, and they are tractable enough that chemical and genetic
    rescue makes a phenotypic drug screen realistic.
  modeled_mechanisms:
  - target: Endosomal PI(4,5)P2 Accumulation and Actin Dysregulation
    relationship: PARTIALLY_RECAPITULATES
    fidelity: MODERATE
    model_scale: CELLULAR
    description: >-
      The renal tubular arm of the model reproduces the endocytic and lysosomal
      consequences of OCRL loss.
    limitations: >-
      The fish models do not separate Dent disease 2 from Lowe syndrome, since
      both are produced by the same ocrl loss; the human distinction rests on
      variant position and residual isoform expression, which these lines do not
      reproduce. Whether the neurodevelopmental defects lie downstream of
      trafficking or of ciliary dysfunction is unresolved in the model itself.
    evidence:
    - reference: PMID:40778266
      reference_title: "Modelling Lowe syndrome and Dent-2 disease using zebrafish."
      supports: SUPPORT
      evidence_source: MODEL_ORGANISM
      snippet: "OCRL-deficient zebrafish also have a renal tubular phenotype, with defective endocytosis, abnormal lysosomal function, and shortening of the renal tubule."
      explanation: Supports treating the fish as informative for the endosomal trafficking node.
  evidence:
  - reference: PMID:40778266
    reference_title: "Modelling Lowe syndrome and Dent-2 disease using zebrafish."
    supports: SUPPORT
    evidence_source: MODEL_ORGANISM
    snippet: "These defects can account for the low molecular weight proteinuria seen in Lowe syndrome and Dent-2 disease and may explain the other renal features seen in both conditions."
    explanation: Connects the model's cellular defects to the defining human phenotype.
  notes: >-
    Ocrl knockout mice are a notable negative: they do not reproduce the human
    disease, which is attributed to compensation by the paralog Inpp5b. That is
    part of why non-mammalian models carry disproportionate weight for Dent
    disease 2.
definitions:
- name: Clinical diagnostic criteria for Dent disease
  definition_type: DIAGNOSTIC_CRITERIA
  derivation_basis: ESTABLISHED_CRITERIA
  description: >
    The long-standing three-part clinical definition, set out in the 2010
    Orphanet review and still the reference frame in the 2025 recommendations.
    All three parts are required. Note that the 2025 guideline goes further and
    states that hypercalciuria is not mandatory, so the criteria are best read
    as a high-specificity case definition rather than an exclusion rule;
    genetic testing is what confirms or excludes the diagnosis.
  inclusion_criteria:
  - preferred_term: Low-molecular-weight proteinuria at least 5-fold above the upper limit of normal
  - preferred_term: Hypercalciuria above 4 mg/kg per 24 hours, or a spot calcium/creatinine ratio above 0.25 mg/mg
  - preferred_term: At least one of nephrocalcinosis, kidney stones, hematuria, hypophosphataemia, or renal insufficiency
  evidence:
  - reference: PMID:20946626
    reference_title: "Dent's disease."
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "The clinical diagnosis of Dent's disease is based on the presence of all three of the following criteria: (i) LMW proteinuria (elevation of urinary excretion of β2-microglobulin, Clara cell protein and/or RBP by at least 5-fold above the upper limit of normality); (ii) hypercalciuria (> 4 mg/kg in a 24 h-hour collection or > 0.25 mg Ca2+ per mg creatinine on a spot sample); and (iii) at least one of the following: nephrocalcinosis, kidney stones, hematuria, hypophosphataemia, or renal insufficiency."
    explanation: The criteria set quoted verbatim, including the quantitative thresholds recorded above.
  - reference: PMID:39794284
    reference_title: "Dent disease: clinical practice recommendations."
    supports: REFUTE
    evidence_source: OTHER
    snippet: "Although hypercalciuria is the second most frequent finding in DD, its absence does not exclude a diagnosis of DD."
    explanation: Refutes treating the hypercalciuria criterion as mandatory, which is why the description qualifies the criteria set.
- name: Case-finding trigger for genetic testing
  definition_type: CASE_DEFINITION
  derivation_basis: ESTABLISHED_CRITERIA
  description: >
    The 2025 guideline's operational trigger for sending CLCN5 and OCRL
    sequencing. It is deliberately broader than the diagnostic criteria, because
    the commonest way to miss the diagnosis is to read nephrotic-range tubular
    proteinuria as glomerular disease and biopsy the patient instead.
  inclusion_criteria:
  - preferred_term: Male with isolated and persistent low-molecular-weight proteinuria
  - preferred_term: Male with mixed proteinuria in the nephrotic range
  - preferred_term: >-
      Male of any age with persistent low-molecular-weight proteinuria plus any
      feature of proximal tubular dysfunction, nephrolithiasis, nephrocalcinosis,
      rickets, or CKD
  evidence:
  - reference: PMID:39794284
    reference_title: "Dent disease: clinical practice recommendations."
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "We recommend genetic testing of the CLCN5 and OCRL genes to confirm the clinical diagnosis of DD1 or DD2 in the following situations (Grade B, strong): Males with isolated and persistent low-molecular-weight proteinuria, or mixed proteinuria in the nephrotic range."
    explanation: The guideline's testing trigger, quoted with its grade.
  - reference: PMID:39794284
    reference_title: "Dent disease: clinical practice recommendations."
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "Low-molecular-weight proteinuria should be excluded before performing a kidney biopsy in patients with nephrotic-range proteinuria and normal serum albumin."
    explanation: States the diagnostic sequencing point that motivates this case definition.
differential_diagnoses:
- name: Lowe syndrome
  disease_term:
    preferred_term: Lowe syndrome
    term:
      id: MONDO:0010645
      label: oculocerebrorenal syndrome
  description: >
    The other OCRL disease, and the closest differential for Dent disease 2
    specifically. It is curated as its own dismech entry. The two sit on one
    allelic spectrum but are clinically distinct.
  distinguishing_features:
  - Dense bilateral congenital cataract, glaucoma, generalised hypotonia, and intellectual disability are obligate or typical in Lowe syndrome and absent or mild in Dent disease 2.
  - Truncating OCRL variants in exons 8-24 give Lowe syndrome; those in exons 1-7 give Dent disease 2.
  - CKD progresses faster in Lowe syndrome than in Dent disease 2.
  evidence:
  - reference: PMID:39794284
    reference_title: "Dent disease: clinical practice recommendations."
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "Lowe syndrome ( OCRL ) | Congenital cataracts, glaucoma, general hypotonia, mental retardation, CKD"
    explanation: The guideline's own differential-diagnosis table row naming the discriminating features.
  - reference: PMID:27708066
    reference_title: "Long-term renal outcome in children with OCRL mutations: retrospective analysis of a large international cohort."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Survival analysis showed that LS was also associated with a faster CKD progression than DD2 (P < 0.01)."
    explanation: Quantifies the renal-outcome difference between the two OCRL phenotypes.
- name: Nephropathic cystinosis
  disease_term:
    preferred_term: cystinosis
    term:
      id: MONDO:0016239
      label: cystinosis
  description: >
    The commonest inherited cause of a full renal Fanconi syndrome in
    childhood, and a routine exclusion before or alongside Dent disease testing.
  distinguishing_features:
  - Corneal cystine crystals and multisystem storage disease, absent in Dent disease.
  - A complete Fanconi syndrome rather than the incomplete, protein-reabsorption-dominant picture of Dent disease.
  evidence:
  - reference: PMID:39794284
    reference_title: "Dent disease: clinical practice recommendations."
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "Nephropathic cystinosis ( CTNS ) | Poor growth, rickets, corneal cystine crystals, CKD"
    explanation: The guideline's differential table row giving the discriminating features of cystinosis.
- name: Idiopathic focal segmental glomerulosclerosis
  description: >
    Not a competing genetic diagnosis so much as the label Dent disease is
    wrongly given. Because the tubular protein load can be nephrotic-range and
    biopsy shows glomerulosclerosis with foot-process effacement, patients are
    treated as steroid-resistant nephrotic syndrome; 13% of one biopsy series
    had a repeat biopsy for steroid-resistant proteinuria.
  distinguishing_features:
  - Serum albumin is normal and there is no oedema, despite nephrotic-range total protein.
  - Urinary protein is low-molecular-weight in origin, demonstrable by retinol-binding protein, beta-2-microglobulin, or an alpha-1-microglobulin/creatinine ratio above 120 mg/g.
  evidence:
  - reference: PMID:27697782
    reference_title: "Glomerular Pathology in Dent Disease and Its Association with Kidney Function."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "A repeat biopsy for steroid-resistant proteinuria was performed in 13% (four of 30) of the patients."
    explanation: Documents that Dent disease patients are in practice managed as steroid-resistant nephrotic syndrome before the diagnosis is made.
  - reference: PMID:39794284
    reference_title: "Dent disease: clinical practice recommendations."
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "Affected individuals may present nephrotic-range proteinuria which may be misinterpreted and cause diagnostic delay."
    explanation: States the misdiagnosis explicitly as a recognised cause of diagnostic delay.
discussions:
- discussion_id: acidification_vs_chloride
  kind: OPEN_QUESTION
  status: OPEN
  prompt: >-
    Is defective endosomal acidification, or luminal chloride accumulation, the
    step through which ClC-5 loss causes proximal tubular endocytic failure?
  attaches_to:
  - pathophysiology#Defective Endosomal Acidification
  - pathophysiology#Megalin and Cubilin Trafficking Failure
  rationale: >
    The textbook account is that ClC-5 supplies the countercurrent for the
    V-ATPase, so its loss impairs acidification and the ligand-receptor complex
    fails to dissociate. A knock-in mouse converting the exchanger into an
    uncoupled chloride channel breaks that account: its endosomes acidify
    normally, and it still shows the full renal phenotype and impaired proximal
    tubular endocytosis. Either luminal chloride concentration matters in its
    own right, or acidification is one of several parallel requirements. The
    question is not decorative: it determines whether a therapeutic strategy
    aimed at restoring endosomal pH could work at all.
  evidence:
  - reference: PMID:20946626
    reference_title: "Dent's disease."
    supports: SUPPORT
    evidence_source: MODEL_ORGANISM
    snippet: "However, despite normal endosomal acidification, KI mice showed the same renal phenotype than KO mice and patients with Dent's disease, including LMW proteinuria, hyperphosphaturia and hypercalciuria."
    explanation: The experimental result that makes the acidification-only account untenable.
- discussion_id: tubulopathy_to_ckd_transition
  kind: KNOWLEDGE_GAP
  status: OPEN
  prompt: >-
    What converts a proximal tubular endocytic defect into progressive chronic
    kidney disease, and why is the trajectory so variable within one family?
  attaches_to:
  - pathophysiology#Tubulointerstitial Fibrosis and Progressive Nephron Loss
  - phenotypes#Chronic kidney disease
  rationale: >
    The guideline states outright that the mechanism of this transition remains
    to be deciphered. Candidate routes are maladaptive proximal tubular
    responses driving inflammation and fibrosis, stress responses in distal
    nephron segments provoked by the tubular protein load, and a genuine
    podocyte component given that CLCN5 and OCRL appear to be expressed in
    podocytes. Because the same variant produces different outcomes within one
    family, whatever governs progression is not the genotype. This is the gap
    that matters most clinically, since kidney failure is what determines
    prognosis and nothing currently available is known to modify it.
  evidence:
  - reference: PMID:39794284
    reference_title: "Dent disease: clinical practice recommendations."
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "The mechanisms behind the transition from proximal tubular dysfunction to progressive chronic kidney disease (CKD) in DD remain to be deciphered."
    explanation: The gap stated by the guideline itself.
  - reference: PMID:39794284
    reference_title: "Dent disease: clinical practice recommendations."
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "Also, the course of kidney failure may be variable within the same family"
    explanation: Establishes that the missing determinant is not the causal variant.
- discussion_id: unexplained_third_of_patients
  kind: KNOWLEDGE_GAP
  status: OPEN
  prompt: >-
    What causes Dent disease in the 25-35% of clinically typical patients with
    no identifiable CLCN5 or OCRL variant?
  attaches_to:
  - genetic#Genetically unexplained Dent disease
  rationale: >
    A quarter to a third of patients meeting the clinical and biochemical
    definition have no variant in either known gene. No third locus has been
    confirmed in the fifteen years since the gap was first described. The
    residual group could reflect an unidentified gene acting on the same
    endocytic apparatus, non-coding or structural variation in CLCN5 or OCRL
    missed by standard sequencing, or phenocopies from a distinct mechanism.
    Until it is resolved, a negative gene panel cannot exclude the diagnosis.
  evidence:
  - reference: PMID:39794284
    reference_title: "Dent disease: clinical practice recommendations."
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "the remaining 25%–35% of patients having neither identifiable CLCN5 nor OCRL variants"
    explanation: Quantifies the unexplained group in the most recent authoritative source.
  - reference: PMID:20946626
    reference_title: "Dent's disease."
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "A few patients with Dent's disease do not harbour mutations in CLCN5 and OCRL1, pointing to the involvement of other genes."
    explanation: Shows the gap was already recognised in 2010 and remains open.
- discussion_id: ocrl_mouse_model_mismatch
  kind: HUMAN_MODEL_MISMATCH
  status: OPEN
  prompt: >-
    Can a mammalian model of Dent disease 2 be built, given that Ocrl knockout
    mice are essentially unaffected because of Inpp5b compensation?
  attaches_to:
  - pathophysiology#OCRL Phosphoinositide 5-Phosphatase Deficiency
  - animal_models#Zebrafish
  rationale: >
    Mouse Ocrl loss does not reproduce the human renal phenotype, which is
    attributed to compensation by the paralog Inpp5b; the double knockout is
    embryonic lethal. The field therefore leans on zebrafish and on patient
    cells for Dent disease 2, and those models do not distinguish Dent disease
    2 from Lowe syndrome, since both arise from ocrl loss and the human
    distinction depends on variant position and residual isoform expression.
    The mismatch is mechanistically meaningful rather than merely inconvenient:
    the human DD2/Lowe boundary is set by how much OCRL activity survives, which
    is exactly the variable a null allele removes.
  evidence:
  - reference: PMID:40778266
    reference_title: "Modelling Lowe syndrome and Dent-2 disease using zebrafish."
    supports: SUPPORT
    evidence_source: MODEL_ORGANISM
    snippet: "Zebrafish has been used to study OCRL function in vivo and to successfully model these two rare genetic conditions."
    explanation: Documents the reliance on a non-mammalian model for both OCRL phenotypes.
  - reference: PMID:34586410
    reference_title: "Identification of novel OCRL isoforms associated with phenotypic differences between Dent disease-2 and Lowe syndrome."
    supports: SUPPORT
    evidence_source: IN_VITRO
    snippet: "Truncating mutations in OCRL exons 1-7 lead to Dent disease-2, whereas those in exons 8-24 lead to Lowe syndrome."
    explanation: Shows the human distinction rests on residual isoform expression, which a null allele cannot model.
references:
- reference: PMID:22876375
  title: "Dent Disease."
  tags:
  - GeneReviews
classifications:
  harrisons_chapter:
  - classification_value: KIDNEY_URINARY_TRACT
  - classification_value: GENETICS_ENVIRONMENT_DISEASE
notes: >
  Scope and lump/split. This entry covers the Dent disease group (MONDO:0015612)
  with both genetic forms as has_subtypes, because they share the proximal
  tubular endocytic mechanism and are clinically near-indistinguishable in the
  kidney. Lowe syndrome is deliberately NOT covered here: it is the severe
  multisystem OCRL phenotype and has its own dismech entry (Lowe_Syndrome),
  whose notes record the same split from the other direction. Dent disease 2 is
  modelled as a subtype rather than duplicated into the Lowe entry, which keeps
  the OCRL allelic spectrum represented once on each side of the clinical
  boundary.

  Evidence base. The two load-bearing sources are the 2025 ERA/ESPN clinical
  practice recommendations (PMID:39794284) and the 2010 Orphanet review
  (PMID:20946626), both open-access full text and both cited throughout. Where
  they disagree the newer source is followed and the disagreement recorded
  rather than smoothed over - most visibly on whether hypercalciuria is a
  mandatory diagnostic criterion.

  Frequency data. Phenotype frequencies are quoted from Table 1 of the 2025
  recommendations, which is a synthesis across roughly fourteen cited series
  rather than a single cohort. Subtype-specific ranges are wide because the
  underlying series are small.

  Deep-research provenance. This entry was curated with
  research/Dent_Disease-deep-research-claude_code.md as a lead list. Nine of
  that report's PMIDs resolve to papers on entirely unrelated subjects and were
  rejected: PMID:11115835 (ulcerative colitis), PMID:12815099 (HIV in
  Langerhans cells), PMID:33710298 (Streptomyces rpoB mutations), PMID:14158899
  (halothane anaesthesia), PMID:20950533 (nutrition environment measures),
  PMID:26296266 (waist circumference in immigrants), PMID:26154403
  (nickel-catalysed alkene chemistry), PMID:11279143 (xeroderma pigmentosum
  centrin), and PMID:25911330 (intrapulmonary genomic profiling). The report's
  suggested MONDO identifiers for the two subtypes were also wrong -
  MONDO:0010655 is X-linked intellectual disability with marfanoid habitus and
  MONDO:0010371 is Aland island eye disease. The correct subtype terms,
  MONDO:0010225 and MONDO:0010359, were taken from the MONDO descendants
  recorded on the curation stub and re-verified against MONDO. Every citation
  in this entry was fetched and read before use.

  Not curated here. Kidney cysts are reported in about a third of Dent disease 1
  patients in the guideline's frequency table, but the table cell for Dent
  disease 2 is empty and no prose in the cached sources discusses the finding,
  so no phenotype record was created. Metabolic acidosis (5-15% in DD1, 5-25% in
  DD2) is likewise recorded in that table but is not separately modelled, being
  a component of the incomplete Fanconi picture already captured by the
  proximal tubular solute-wasting node.

  GeneReviews baseline. The chapter (PMID:22876375) is tagged and mined across
  all four of its clinical domains: clinical characteristics on the chronic
  kidney disease phenotype and the Dent disease 2 cataract, diagnosis and
  surveillance in the diagnosis section, management on thiazides and on
  nephrotoxin avoidance, and genetic counselling on the inheritance block.
  The cached record is abstract-only, so three claims the chapter is elsewhere
  cited for - the roughly 74% of CLCN5 variants private to a single family, the
  sequence-analysis detection rates, and germline mosaicism in carrier mothers -
  are not present in the cached text and are deliberately not curated. They sit
  in the full chapter body, which is not in the cache, and quoting them would
  mean asserting text no committed source contains.

📚

References & Deep Research

References

1

PMID:22876375

Dent Disease.

No top-level findings curated for this source.

Deep Research

1

Deep research results are used as seeds for research; they do not undergo the same validation as the main records and may contain errors. How we use deep research.

Evaluations and curation notes (2)

Record notes

Scope and lump/split. This entry covers the Dent disease group (MONDO:0015612) with both genetic forms as has_subtypes, because they share the proximal tubular endocytic mechanism and are clinically near-indistinguishable in the kidney. Lowe syndrome is deliberately NOT covered here: it is the severe multisystem OCRL phenotype and has its own dismech entry (Lowe_Syndrome), whose notes record the same split from the other direction. Dent disease 2 is modelled as a subtype rather than duplicated into the Lowe entry, which keeps the OCRL allelic spectrum represented once on each side of the clinical boundary. Evidence base. The two load-bearing sources are the 2025 ERA/ESPN clinical practice recommendations (PMID:39794284) and the 2010 Orphanet review (PMID:20946626), both open-access full text and both cited throughout. Where they disagree the newer source is followed and the disagreement recorded rather than smoothed over - most visibly on whether hypercalciuria is a mandatory diagnostic criterion. Frequency data. Phenotype frequencies are quoted from Table 1 of the 2025 recommendations, which is a synthesis across roughly fourteen cited series rather than a single cohort. Subtype-specific ranges are wide because the underlying series are small. Deep-research provenance. This entry was curated with research/Dent_Disease-deep-research-claude_code.md as a lead list. Nine of that report's PMIDs resolve to papers on entirely unrelated subjects and were rejected: PMID:11115835 (ulcerative colitis), PMID:12815099 (HIV in Langerhans cells), PMID:33710298 (Streptomyces rpoB mutations), PMID:14158899 (halothane anaesthesia), PMID:20950533 (nutrition environment measures), PMID:26296266 (waist circumference in immigrants), PMID:26154403 (nickel-catalysed alkene chemistry), PMID:11279143 (xeroderma pigmentosum centrin), and PMID:25911330 (intrapulmonary genomic profiling). The report's suggested MONDO identifiers for the two subtypes were also wrong - MONDO:0010655 is X-linked intellectual disability with marfanoid habitus and MONDO:0010371 is Aland island eye disease. The correct subtype terms, MONDO:0010225 and MONDO:0010359, were taken from the MONDO descendants recorded on the curation stub and re-verified against MONDO. Every citation in this entry was fetched and read before use. Not curated here. Kidney cysts are reported in about a third of Dent disease 1 patients in the guideline's frequency table, but the table cell for Dent disease 2 is empty and no prose in the cached sources discusses the finding, so no phenotype record was created. Metabolic acidosis (5-15% in DD1, 5-25% in DD2) is likewise recorded in that table but is not separately modelled, being a component of the incomplete Fanconi picture already captured by the proximal tubular solute-wasting node. GeneReviews baseline. The chapter (PMID:22876375) is tagged and mined across all four of its clinical domains: clinical characteristics on the chronic kidney disease phenotype and the Dent disease 2 cataract, diagnosis and surveillance in the diagnosis section, management on thiazides and on nephrotoxin avoidance, and genetic counselling on the inheritance block. The cached record is abstract-only, so three claims the chapter is elsewhere cited for - the roughly 74% of CLCN5 variants private to a single family, the sequence-analysis detection rates, and germline mosaicism in carrier mothers - are not present in the cached text and are deliberately not curated. They sit in the full chapter body, which is not in the cache, and quoting them would mean asserting text no committed source contains.

Create: Dent Disease · 2026-09-11T22:54:00Z · View source

De novo curation of Dent disease (MONDO:0015612), closing issue #11701 and deleting stubs/Dent_Disease.yaml. Scope and lump/split. Curated at the Dent disease group level with both genetic forms as has_subtypes: DD1 (CLCN5, MONDO:0010225) and DD2 (OCRL, MONDO:0010359). Lowe syndrome was deliberately left as its own entry -- kb/disorders/Lowe_Syndrome.yaml already frames itself as split from Dent disease-2, and this entry's notes record the reciprocal decision so the OCRL allelic spectrum is represented once on each side of the clinical boundary rather than duplicated. The justification is cited: the guideline states the proximal tubular manifestations overlap between DD1 and DD2, and the largest DD2 cohort concludes DD2 is distinct from Lowe syndrome. Content. 11 pathophysiology nodes forming a two-entry-point chain (ClC-5 loss and OCRL deficiency) converging on megalin/cubilin trafficking failure, then branching to protein reabsorption failure, vitamin D/PTH loss, generalised solute wasting, calcium supersaturation, and fibrosis. 17 phenotypes, 8 treatments with target_mechanisms links, 4 animal models with modeled_mechanisms and readouts, 3 progression phases, 2 definitions (diagnostic criteria and a genetic-testing case definition), 3 differential diagnoses, and 4 discussions. Module conformance. Two nodes conform to nephrolithiasis_crystal_nucleation -- "Urinary Calcium Supersaturation" to #Urinary Supersaturation (substituting calcium as the lithogenic solute, with the module's GO:0007588 and GO:0006816 bindings carried through) and "Calcium Crystal Nucleation and Retention" to #Crystal Nucleation and Growth. Evidence. 140 evidence snippets across 12 PMIDs, every one verified as an exact substring of a fetched references_cache entry. Load-bearing sources are the 2025 ERA/ESPN clinical practice recommendations (PMID:39794284) and the 2010 Orphanet review (PMID:20946626), both open-access full text. Where the two disagree -- notably on whether hypercalciuria is a mandatory diagnostic criterion -- the newer source is followed and the disagreement recorded as a REFUTE evidence item rather than smoothed over. REFUTE items are also used for the three places where an intuitive inference is wrong: endosomal acidification failure is not the whole mechanism (knock-in mouse), CLCN5 variant class does not predict severity, and the standard hypophosphataemic-rickets vitamin D regimen must not be transferred to this disease. Deep-research triage. research/Dent_Disease-deep-research-claude_code.md was used as a lead list only. Nine of its PMIDs resolve to papers on unrelated subjects and were rejected after fetching and reading each cache file: PMID:11115835 (ulcerative colitis), PMID:12815099 (HIV in Langerhans cells), PMID:33710298 (Streptomyces rpoB), PMID:14158899 (halothane anaesthesia), PMID:20950533, PMID:26296266, PMID:26154403, PMID:11279143, PMID:25911330. Four of those nine were misattributed to real, relevant Dent disease papers in the report's own reference list, so the citation text looked correct. The report's MONDO subtype identifiers were also wrong (MONDO:0010655 is X-linked intellectual disability with marfanoid habitus; MONDO:0010371 is Aland island eye disease); the correct terms were taken from the stub's mondo_descendants and re-verified against MONDO via OLS. The rejections and the MONDO correction are recorded in the entry's own notes so a later curator does not re-import them. Ontology bindings. hgnc:2023 (CLCN5) was derived from `runoak -i sqlite:obo:hgnc search "l^CLCN5"` and independently corroborated by a curator note in kb/disorders/Hypopigmentation_Organomegaly_And_Delayed_Myelination_And_Development.yaml; hgnc:8108 (OCRL) from cache/hgnc/terms.csv and the existing Lowe syndrome binding. GO:0062158 (chloride:proton antiporter activity) and GO:0048388 (endosomal lumen acidification) were resolved live via the ols: adapter. NCIT:C29372, NCIT:C49185, NCIT:C837, CHEBI:5778 and CHEBI:3654 were each looked up rather than recalled; the report's CHEBI:32029 for potassium citrate was rejected (it is potassium acetate). Validation. `just validate-disorders` passes (schema, terms, references, 140/140 snippets). Also green: validate, validate-terms, count-verified-snippets, check-duplicate-keys, check-entity-refs, check-causal-targets, check-qualifier-terms, check-enum-values, check-snippet-length, check-title-snippets, check-snippet-grading, check-reference-titles, check-folded-hyphens, check-environmental-evidence. Known gaps. No datasets, biochemical reference ranges, clinical trials, or experimental_models block. Kidney cysts and metabolic acidosis appear in the guideline frequency table but have no supporting prose in the cached sources, so they were left uncurated rather than given a table-row-only phenotype record; this is stated in the entry's notes.

Claude Code ▸

Dent Disease: Comprehensive Research Report

claude-haiku-4-5-20251001, claude-opus-4-7[1m] 28 citations 2026-09-11T12:55:56.802044

Dent Disease: Comprehensive Research Report

Target MONDO ID: MONDO:0015612 (Dent disease group) Report compiled: 2026-09-11

1. Disease Information

Overview

Dent disease is a rare X-linked recessive renal proximal tubulopathy defined by the triad of low-molecular-weight proteinuria (LMWP), hypercalciuria, and at least one additional feature (nephrocalcinosis, nephrolithiasis, hematuria, hypophosphatemia, or renal insufficiency). It principally affects males and progresses to end-stage kidney disease (ESKD) in 30–80% of affected males between the third and fifth decades (Bhardwaj et al., 2021; Gianesello et al., 2021; Blanchard et al., 2025, PMID:39794284).

Key Identifiers

Resource	Identifier
MONDO (group)	MONDO:0015612 (Dent disease)
MONDO (DD1)	MONDO:0010655
MONDO (DD2)	MONDO:0010371
OMIM DD1	#300009
OMIM DD2	#300555
Orphanet	ORPHA:1652
ICD-10	N25.8 (Other disorders resulting from impaired renal tubular function)
ICD-11	GB90.4Y
MeSH	D058637 (Dent Disease)
Gene DD1	CLCN5 (HGNC:2023), Xp11.23
Gene DD2	OCRL (HGNC:8108), Xq26.1

Synonyms / Alternative Names

X-linked recessive nephrolithiasis with renal failure (XRN)
X-linked recessive hypophosphatemic rickets (XLRH)
Low-molecular-weight proteinuria with hypercalciuria and nephrocalcinosis (LMWP-HC-NC)
Idiopathic low molecular weight proteinuria of Japanese children
Dent's disease
Nephrolithiasis type I (Dent) — original description by C.E. Dent and Friedman (1964, PMID:14158899)

Data Derivation

Information is derived from a combination of case reports, national registries (Japan n=91, France n=108, UK n=62; Blanchard 2025), international multicenter cohorts, and functional/molecular studies. Individual-level EHR-scale data is limited; the disease is aggregated primarily through registries and expert-consensus guidelines (Blanchard et al., 2025, PMID:39794284).

2. Etiology

Disease Causal Factors

Dent disease is monogenic, with a strictly Mendelian X-linked recessive etiology. Two subtypes are recognized:

Dent Disease 1 (DD1, ~60%): caused by loss-of-function variants in CLCN5 encoding the electrogenic 2Cl⁻/H⁺ exchanger ClC-5.
Dent Disease 2 (DD2, ~15%): caused by hypomorphic/truncating variants in OCRL encoding phosphatidylinositol-4,5-bisphosphate 5-phosphatase.
Dent-3 / unclassified (~25%): no CLCN5/OCRL mutation identified; other candidate loci have been proposed (e.g., involvement of endocytic machinery) but not confirmed (Devuyst & Thakker, 2010, PMID:20950533).

There is no established environmental etiology; the disease is not infectious or toxic in origin.

Risk Factors

Genetic risk factors: - Male sex — hemizygous males manifest the classic phenotype; approximately 70% of carrier females show mild LMWP and 50% show mild hypercalciuria due to X-inactivation (Devuyst & Thakker, 2010). - Family history of X-linked nephrolithiasis or LMWP. - Modifier alleles in the ClC-5–megalin–cubilin endocytic complex (proposed but not clinically validated).

Environmental risk factors: - Not a driver of disease onset. However, iatrogenic exposure to nephrotoxins (aminoglycosides, NSAIDs, IV iodinated contrast) worsens outcomes in established DD (GeneReviews, Bhardwaj 2021). - Dehydration and low urinary volume potentiate stone formation and nephrocalcinosis.

Protective Factors

Alkaline urine (e.g., high citrate intake) reduces calcium-oxalate/phosphate supersaturation and nephrocalcinosis. In Clcn5-KO mice, a high-citrate diet preserved GFR at 9 months versus zero-citrate controls (Cebotaru et al., 2005, PMID:16014041).
No genetic protective alleles have been formally characterized in humans.

Gene-Environment Interactions

No formal GxE analyses have been published; treatment response variability (e.g., citrate, thiazide) may reflect underlying variant class effects on the endocytic machinery.

3. Phenotypes

Core Renal Phenotypes (with HPO term suggestions and frequencies)

Phenotype	HPO Term	Frequency (DD1)	Frequency (DD2)
Low-molecular-weight proteinuria	HP:0003126	~99–100%	~100%
Hypercalciuria	HP:0002150	44–90%	80–100%
Nephrocalcinosis	HP:0000121	40–75%	10–40%
Nephrolithiasis (kidney stones)	HP:0000787	20–50%	10–15%
Hematuria (usually microscopic)	HP:0000790	Common	Common
Chronic kidney disease	HP:0012622	30–80% (by 3rd–5th decade)	Lower/later
Hypophosphatemia	HP:0002148	20–45%	Common
Aminoaciduria	HP:0003355	Frequent	Frequent
Glycosuria	HP:0003076	Frequent	Frequent
Renal tubular acidosis	HP:0001947	Occasional	Occasional
Rickets	HP:0002748	5–33%	10–20%
Osteomalacia	HP:0002749	Adult-onset	Rare
Hypokalemia	HP:0002900	20–40%	10–20%
Focal segmental glomerulosclerosis	HP:0000097	Reported in biopsies	Reported
Growth retardation	HP:0001510	10–20%	60–80%
Elevated β2-microglobulin, α1-microglobulin	HP:0032122	Universal	Universal

Source: Blanchard et al., 2025, PMID:39794284; Wang et al., 2015, PMID:26296266.

DD2-Specific Extra-Renal Phenotypes (from OCRL mutations)

Phenotype	HPO Term	Frequency
Mild intellectual disability	HP:0001256	~46% (with extra-renal features)
Elevated serum creatine kinase	HP:0003236	~52%
Elevated lactate dehydrogenase	HP:0025435	Common
Muscle weakness / hypotonia	HP:0001252	Occasional
Cataracts (rare)	HP:0000518	~11% (non-congenital; contrast with Lowe syndrome universal congenital bilateral cataracts)

Source: Gianesello et al., 2021 (PMID:34680992); Prosseda 2020.

Phenotype Characteristics

Age of onset: Typically pediatric (childhood, often <10 years). Some individuals only manifest as adults with isolated hypercalciuria.
Severity: Highly variable, ranging from asymptomatic hypercalciuria to childhood-onset CKD with rickets. Considerable intra-familial variability.
Progression: Slowly progressive; mean eGFR decline ~1.5 mL/min/1.73m²/year (Blanchard et al., 2025).
Course: Chronic and progressive; kidney stones may recur episodically.
Quality-of-life impact: Substantial burden from recurrent stones, need for dialysis/transplant in some, growth retardation in children with DD2, learning disability in a subset (DD2), and bone pain from osteomalacia/rickets.

"Nephrotic-Range" Proteinuria Pitfall

Because total urinary protein excretion can exceed 3.5 g/day due to massive LMWP, patients are frequently misdiagnosed as having idiopathic nephrotic syndrome or FSGS unless urine protein electrophoresis or β2-microglobulin/α1-microglobulin are measured (Copelovitch et al., 2015, PMID:26154403).

4. Genetic / Molecular Information

Causal Genes

CLCN5 (DD1) - Chromosome: Xp11.23 - Structure: 12 exons; encodes 746-aa electrogenic 2Cl⁻/H⁺ exchanger ClC-5 - OMIM: 300008 (gene) - HGNC: hgnc:2023 - UniProt: P51795 - Function: Endosomal Cl⁻/H⁺ exchanger essential for efficient endosomal acidification in the renal proximal tubule.

OCRL (DD2) - Chromosome: Xq26.1 - Structure: 24 exons (23 coding); encodes a phosphatidylinositol 4,5-bisphosphate 5-phosphatase (OCRL1) - OMIM: 300535 (gene) - HGNC: hgnc:8108 - UniProt: Q01968 - Function: Hydrolyzes PI(4,5)P₂ to PI4P at endosomes; regulates trafficking, cytoskeletal dynamics, and cilia. Also mutated in Lowe (oculocerebrorenal) syndrome (OMIM #309000).

Pathogenic Variants

CLCN5 variants (from the 2026 curated database, Lu et al., Kidney International Reports, DOI:10.1016/j.ekir.2026.106475): - 524 unique pathogenic/likely pathogenic variants - Missense: 31% | InDel: 37% | Nonsense: 14% | Splicing: 13% | Large deletions: 5% - ~63% frameshift/truncating (loss of full-length protein) - Hotspot: Exon 10 has ~50.6 variants/100 nt (~3× average) - Helix H shows the highest non-truncating variant density (~200/100 residues); helices O–Q also enriched

Functional classes (Grand et al., 2009; PMID:19019917): - Class 1: ER-retained/degraded (loss of ClC-5 at endosomes) - Class 2: Correctly trafficked but with abnormal Cl⁻/H⁺ exchange or channel activity - Class 3: Reduced ion transport with preserved endosomal targeting

OCRL variants (DD2 vs Lowe syndrome): - Truncating variants in exons 1–7 cluster in the PH domain → DD2 - Truncating variants in exons 8–24 → Lowe syndrome - Missense variants: DD2-associated variants retain >50% enzymatic activity; Lowe variants retain <20% activity (Hichri et al., 2011; Gianesello et al., 2021, PMID:34680992) - Reinitiation from an internal methionine (Met170) in truncating variants may partially rescue activity, explaining the milder DD2 phenotype - Compensation by INPP5B, an OCRL paralog with ~45% sequence identity, further contributes

Variant Classification

Variants are classified by ACMG/AMP guidelines (Richards et al., 2015, PMID:25741868). Recent literature databases and ClinVar entries include a mixture of pathogenic (P), likely pathogenic (LP), and VUS annotations. Approximately 74% of CLCN5 pathogenic variants are private (single-family) (GeneReviews).

Allele Frequency

CLCN5 and OCRL LoF variants are extremely rare in population databases (gnomAD v4); pathogenic Dent variants are typically absent or singleton in unaffected controls. Female carrier frequency has not been precisely quantified.

Somatic vs. Germline

All disease-causing variants are germline. Germline mosaicism in mothers of affected males has been reported and complicates recurrence counseling (GeneReviews). De novo variants also occur; their frequency has not been precisely quantified.

Functional Consequences

Both DD1 and DD2 mechanisms are loss-of-function: - CLCN5: loss of endosomal Cl⁻/H⁺ exchange → impaired endosomal acidification and endocytic trafficking - OCRL: loss of 5-phosphatase activity → altered PI(4,5)P₂/PI4P balance at endosomes/actin, disrupting endocytic recycling and cytoskeletal remodeling

Modifier Genes

No formal modifier loci are established. Candidate interactors include TMEM9 and SEC22B, reported to shape proximal tubule function and DD1 pathogenesis (bioRxiv, Nov 2025, DOI:10.1101/2025.11.03.686312).

Epigenetic Information

No consistent epigenetic pattern has been reported. X-inactivation skewing modulates the phenotype in heterozygous females.

Chromosomal Abnormalities

Large intragenic deletions of CLCN5 or OCRL account for ~5–7% of cases; contiguous gene deletions have been described but are rare.

5. Environmental Information

Dent disease is a monogenic disorder. Environmental factors do not cause the disease but modulate outcomes: - Nephrotoxins to avoid: aminoglycosides, NSAIDs, iodinated IV contrast, cisplatin (Bhardwaj 2021). - Hydration and low dietary sodium reduce hypercalciuria and stone risk. - Dietary calcium restriction is not recommended given bone health concerns. - No infectious agents are involved.

6. Mechanism / Pathophysiology

Ordered Causal Chain (DD1, CLCN5-related)

Loss-of-function variant in CLCN5 → loss or misfolding of the ClC-5 2Cl⁻/H⁺ exchanger at proximal-tubule (PT) subapical endosomes (Piwon et al., 2000, PMID:11099045; Wang et al., 2000, PMID:11115835).
Defective ClC-5 → impaired endosomal Cl⁻ counterion transport → reduced V-ATPase-mediated endosomal acidification and abnormal luminal [Cl⁻] (Devuyst & Thakker, 2010).
Reduced endosomal acidification → impaired recycling and trafficking of megalin and cubilin (LRP2/CUBN) at the brush border (Christensen et al., 2003, PMID:12815099).
Loss of megalin/cubilin at the apical membrane → failure of receptor-mediated endocytosis of filtered LMW proteins → LMW proteinuria (β2-microglobulin, α1-microglobulin, RBP, vitamin-binding proteins).
Loss of vitamin D-binding protein (DBP) reabsorption → urinary 25(OH)-vitamin D loss → paradoxical elevated 1,25(OH)₂-vitamin D → increased intestinal calcium absorption → hypercalciuria (Norden et al., 2001, PMID:11279143; Maritzen et al., 2006).
Hypercalciuria + defective proximal reabsorption of phosphate → calcium-phosphate supersaturation → nephrocalcinosis / nephrolithiasis.
Chronic tubular injury → tubulointerstitial fibrosis and focal global/segmental glomerulosclerosis → progressive CKD and eventual ESKD.

Ordered Causal Chain (DD2, OCRL-related)

Hypomorphic OCRL variant → residual PI(4,5)P₂ 5-phosphatase activity (>50%) but reduced flux (Hichri 2011).
Elevated endosomal PI(4,5)P₂ → aberrant actin polymerization on endosomal membranes; disrupted trafficking of megalin/cubilin (Vicinanza et al., 2011).
Trafficking defect → same downstream LMW proteinuria and hypercalciuria as DD1, plus mild extra-renal features (elevated CK/LDH, mild intellectual disability) from OCRL's role in ciliogenesis, endosomal PI cycling in muscle/CNS.
The absence of complete phosphatase loss (unlike Lowe syndrome) explains milder ocular and CNS phenotype.

Molecular Pathways

Endocytic recycling (megalin/cubilin/amnionless complex; Rab5/Rab7/Rab11)
V-ATPase / endosomal acidification
Vitamin D metabolism (CYP24A1, CYP27B1)
Phosphoinositide signaling (PI(4,5)P₂/PI4P; PI3K–AKT downstream)
Actin cytoskeleton remodeling (OCRL–Rho–GAP)
Autophagy/lysosomal degradation (impaired lysosomal delivery in ClC-5-null cells; De Matteis et al.)
Suggested GO terms: GO:0006897 (endocytosis), GO:0006508 (proteolysis) (mislocalized), GO:0008286 (insulin receptor-signaling – megalin cargo), GO:0006874 (cellular calcium ion homeostasis), GO:0055074 (calcium ion homeostasis), GO:0055062 (phosphate ion homeostasis), GO:0043647 (inositol phosphate metabolic process).

Cellular Processes

Impaired receptor-mediated endocytosis (Christensen 2003)
Defective endosomal maturation and recycling
Increased apoptosis of proximal tubule cells
Reduced primary cilium function (OCRL)
Chronic tubulointerstitial inflammation and fibrosis

Protein Dysfunction

Class 1 CLCN5 variants: misfolding → ER retention → proteasomal degradation
Class 2/3: preserved trafficking but altered ion transport
OCRL variants (DD2): reduced but not abolished 5-phosphatase catalysis

Metabolic / Biochemical Abnormalities

Elevated urinary β2-microglobulin, α1-microglobulin, retinol-binding protein
Elevated 1,25(OH)₂D₃, hypercalciuria, hypophosphatemia
Aminoaciduria, glycosuria, uricosuria, kaliuresis
Impaired urinary acidification (partial RTA in some)

Tissue Damage Mechanisms

Chronic calcium deposition → interstitial fibrosis; oxidative stress; protein overload of tubular cells; glomerulosclerosis secondary to hyperfiltration and podocyte injury.

Immune / Inflammation

Chronic low-grade interstitial lymphocytic infiltration on biopsy (~53% of biopsies; Wang et al., 2016, PMID:27697782).

Molecular Profiling

Transcriptomic studies in Clcn5-KO models identified dysregulation of endocytic, autophagy, and lipid-metabolism gene sets (Gorvin et al., 2013; Cellular models Perego et al., 2021, PMID:33710298).
Novel candidate interactors TMEM9, SEC22B recently identified (2025).

Advanced Technologies

Single-cell studies: Not yet published for DD, though PT cell heterogeneity models are being generated.
Drosophila model (2026, PMID:41690574) revealed impaired ER export of Cubilin as a novel pathogenic mechanism.

7. Anatomical Structures Affected

Organ Level

Primary: Kidney — specifically the renal cortex (UBERON:0001225)
Secondary: Skeleton (rickets/osteomalacia); occasionally eye (mild non-congenital cataracts in DD2 subset)

Tissue and Cell Level

Renal proximal tubule (UBERON:0004134)
Renal proximal convoluted tubule cell (CL:1000838) — primary site of expression of ClC-5
Renal proximal straight tubule (S3 segment) cell — secondary
Podocytes — secondary involvement leading to FSGS-like lesions
Intercalated cells of the collecting duct — ClC-5 also expressed, but PT is dominant

Subcellular Level

Early/subapical endosomes (GO:0005769; endocytic vesicle)
Apical brush border membrane (megalin/cubilin)
Lysosomes (secondary dysfunction)
Endoplasmic reticulum (site of misfolded Class-1 ClC-5 retention)

Anatomical Localization

Bilateral kidney involvement
Nephrocalcinosis typically medullary (renal medulla, UBERON:0000362)

8. Temporal Development

Onset

Typical age: Pediatric — often <10 years. LMWP may be detected incidentally in asymptomatic males or during workup of hematuria or stones.
Onset pattern: Chronic and insidious; acute manifestations only when kidney stones present with pain/hematuria.

Progression

Rate: Slow. Mean eGFR decline ~1.5 mL/min/1.73 m²/year (Blanchard 2025).
Stages: Preclinical → biochemical (LMWP + hypercalciuria) → complications (stones, rickets) → CKD → ESKD.
Course: Chronic, non-remitting, progressive in the majority.
Duration: Lifelong.

Age Distribution of Kidney Failure

30-40 years: ~40% of affected males
40-50 years: ~33%
50-60 years: ~75%
Very rare progression before adolescence (Blanchard 2025).

Critical Periods

Adolescence and early adulthood are important intervention windows for stone prevention. Childhood is the critical period for growth and bone health.

9. Inheritance and Population

Epidemiology

Prevalence: ≥1 in 500,000 to 1 in 1,000,000 based on European registries; likely underdiagnosed. New 2026 estimates from a curated CLCN5 database suggest ~3,520 affected families globally (Lu et al., Kidney International Reports, 2026, DOI:10.1016/j.ekir.2026.106475).
Historical count: ~250 published families before 2024.

Inheritance

Pattern: X-linked recessive
Penetrance: Essentially complete in hemizygous males; variable in heterozygous females (partial expression from X-inactivation).
Expressivity: Highly variable — even within families with the same variant, phenotype ranges from isolated hypercalciuria to early CKD.
Genetic anticipation: Not observed.
Germline mosaicism: Reported for CLCN5 (relevant to genetic counseling).
Founder effects: No known population-specific founder mutations; ~74% CLCN5 variants are private.
Consanguinity: Not required (X-linked); does not increase risk beyond X-linked transmission.
Carrier frequency: Not precisely known; exceedingly rare given ultra-low disease prevalence.

Population Demographics

Sex ratio: M:F ≈ 100:1 in symptomatic disease; heterozygous females largely subclinical.
Ethnicity: Reported worldwide with no ethnic predilection — cases documented in European, Japanese, Chinese, North American, Middle Eastern, and African populations.
Geographic distribution: Global; slightly higher recognition in countries with early school-screening programs (e.g., Japan, where routine urinary protein screening detects asymptomatic pediatric cases).

10. Diagnostics

Clinical Tests

Urine dipstick + microscopy: proteinuria, hematuria, crystalluria
Quantitative urine protein electrophoresis: demonstrates LMWP predominance
Urinary β2-microglobulin (LOINC:1953-0) and α1-microglobulin (LOINC:56546-1): both >10× normal
24-hour urinary calcium (>4 mg/kg/day) or spot Ca:Cr ratio (>0.25 mg/mg)
Urinary α1-microglobulin/creatinine ratio >120 mg/g (13.6 mg/mmol) — highly specific for DD (Blanchard 2025)
Urine albumin/total protein ratio <21% distinguishes DD from glomerular proteinuria
Serum creatinine + eGFR to track renal function
Serum electrolytes: hypokalemia, hypophosphatemia
Serum bicarbonate: acidosis in some
Serum 25(OH)D, 1,25(OH)₂D, PTH, phosphate, ALP
Urinary phosphate, amino acids, glucose, uric acid — assess extent of Fanconi-like tubular defect

Imaging

Renal ultrasound: cornerstone for nephrocalcinosis and stone detection (annual)
CT scan (low-dose): for confirming stones when ultrasound is inconclusive
Skeletal radiographs: for rickets/osteomalacia

Pathology (biopsy findings)

Focal global glomerulosclerosis in ~83% of biopsies (Wang et al., 2016, PMID:27697782)
Segmental foot-process effacement (~57%)
Focal interstitial fibrosis (~60%)
Interstitial lymphocytic infiltration (~53%)
Tubular damage (~70%)
Calcium deposits in tubular lumens (nephrocalcinosis)

Kidney biopsy is not required for diagnosis when biochemical + genetic criteria are met, but historically many patients underwent biopsy for undiagnosed FSGS.

Genetic Testing

Recommended approach (2025 guideline): genetic testing of CLCN5 and OCRL in all males with LMWP and hypercalciuria
Sequence analysis of CLCN5 detects ~92%; OCRL ~95% of variants (GeneReviews)
Multigene renal-tubulopathy or Fanconi panels are commonly used
Whole exome/genome sequencing for unresolved cases and to exclude phenocopies (cystinosis, Lowe syndrome, mitochondrial cytopathies)
Deletion/duplication analysis for negative sequence-only results

Clinical Diagnostic Criteria (2010 / reaffirmed 2025)

All three required (Devuyst & Thakker, 2010; Blanchard 2025): 1. LMW proteinuria ≥5× ULN 2. Hypercalciuria (>4.0 mg/kg/24 h or Ca:Cr >0.25 mg/mg) 3. At least one: nephrocalcinosis, nephrolithiasis, hematuria, hypophosphatemia, or CKD, or X-linked family history + genetic confirmation

Differential Diagnosis

Lowe syndrome (also OCRL — with ocular/CNS features)
Cystinosis (CTNS)
Wilson disease (ATP7B)
Galactosemia (GALT)
Mitochondrial cytopathies
Fanconi-Bickel syndrome (SLC2A2)
Idiopathic hypercalciuria
Autoimmune tubulointerstitial nephritis
Aminoglycoside/cisplatin/tenofovir tubulopathy
Idiopathic FSGS (misdiagnosis pitfall)

Screening

Newborn screening: not routine for Dent disease; some Japanese school-age urine screening programs identify affected boys.
Cascade genetic screening for at-risk family members (males and female carriers).

11. Outcome / Prognosis

Survival and Mortality

Overall survival is generally good until ESKD; life expectancy is largely determined by CKD progression and dialysis/transplant outcomes.
No disease-specific mortality tables available.

Morbidity / Disability

Recurrent nephrolithiasis, hospitalizations
Growth failure (especially DD2), rickets
Bone pain, osteomalacia
ESKD-related disability

Disease Course

Complications: nephrolithiasis, nephrocalcinosis, ESKD, rickets/osteomalacia, growth retardation, rarely hypokalemia-related complications, mild cognitive impairment (DD2)
Recovery potential: No recovery; kidney transplantation is curative for renal manifestations; disease does not recur post-transplant.

Prognostic Factors

Higher globally sclerotic glomeruli %, greater foot-process effacement, interstitial inflammation → lower eGFR at biopsy and steeper decline (Wang 2016).
Nephrotic-range albuminuria at presentation associated with worse prognosis.
Class 1 CLCN5 mutations (ER-retained) may show slightly more severe course (contested).

Prognostic Biomarkers

Serum creatinine / eGFR trajectory
Proteinuria magnitude
Age at first stone
Presence of nephrocalcinosis on imaging

12. Treatment

Current management is supportive. No disease-modifying or gene therapies are FDA-approved. The 2025 European guideline (Blanchard et al., 2025, PMID:39794284) provides evidence-graded recommendations.

Pharmacotherapy

Potassium citrate (NCIT:C87206 / CHEBI:32029) - Rationale: alkalinizes urine, reduces calcium-oxalate/phosphate supersaturation, delays CKD in Clcn5-KO mice (Cebotaru 2005, PMID:16014041) - Grade C (weak); commonly used in 13–25% of patients - Dose: pediatric 1–2 mEq/kg/day; adult 20–60 mEq/day

Thiazide diuretics (hydrochlorothiazide, NCIT:C29081) - Reduce urinary calcium excretion by up to 40% at 0.4–1 mg/kg/day (Raja et al., 2002, PMID:12444212; Blanchard 2008, PMID:18976849) - 2025 guideline: NOT recommended systematically due to hypokalemia, volume depletion, hypocitraturia; use with caution if needed (Grade B, moderate)

ACE inhibitors / ARBs - Not recommended as routine nephroprotection (Grade C, moderate); no proven benefit in DD-associated FSGS

Phosphate supplements + calcitriol/1α-hydroxyvitamin D - For hypophosphatemic rickets (individualized) - Vitamin D repletion if 25(OH)D deficient; monitor calciuria

Vitamin A supplementation - Consider if urinary RBP/retinol loss causes deficiency (Grade B, moderate)

Human growth hormone (somatropin) - Only if growth retardation with inadequate metabolic control or CKD ≥3

Advanced Therapeutics

Gene therapy: experimental only; AAV-mediated CLCN5 delivery has been proposed but no clinical trials.
Cell therapy: none clinically available.
RNA-based therapies: none in clinical use for Dent disease.
Small-molecule chaperones to rescue Class-1 misfolded ClC-5 mutants are being explored preclinically (Perego 2021, PMID:33710298).

Surgical / Interventional

Extracorporeal shock wave lithotripsy (ESWL), ureteroscopy, or percutaneous nephrolithotomy for stones (NCIT:C15329)
Kidney transplantation (NCIT:C15289) — curative for renal manifestations; no disease recurrence

Supportive / Rehabilitative

High fluid intake (>2 L/day adults; equivalent weight-based in children)
Balanced dietary calcium (avoid restriction)
Sodium restriction to reduce urinary calcium
Physical therapy for bone deformities
Genetic counseling

Experimental / Clinical Trials

No open Phase III interventional trials targeting molecular pathogenesis (as of 2026).
Preclinical: AAV gene addition, base editing for CLCN5; zebrafish and Drosophila models for high-throughput drug screening (Modelling Lowe syndrome and Dent-2 in zebrafish, 2025, PMID:40778266; Drosophila DD1 model, 2026, PMID:41690574).

Treatment Outcomes / Adverse Effects

Thiazides: hypokalemia, volume depletion, tubulointerstitial nephritis (Bailey et al., 2015, PMID:25911330)
Citrate: GI intolerance, hyperkalemia in advanced CKD
Growth hormone: generally well tolerated in this context

Treatment Strategy

Personalized to phenotype: stone-formers → citrate ± hydration ± thiazide (cautious)
Rickets → phosphate + calcitriol
CKD → standard nephroprotection (blood-pressure control, avoid nephrotoxins)
Multidisciplinary: nephrology, urology, endocrinology, genetics, orthopedics

Monitoring (per 2025 Guideline)

Clinical + biochemical: every 3–6 months
Renal ultrasound: annually
Blood pressure, growth, bone health each visit
Escalate frequency at CKD stage ≥3B (eGFR <45)

13. Prevention

Primary Prevention

Not preventable at disease-onset level (monogenic).
Preimplantation genetic diagnosis (PGD) available for known familial CLCN5/OCRL mutations.
Prenatal testing for known familial variants.

Secondary Prevention

Early diagnosis via urinary protein screening in males with family history
Cascade genetic screening of maternal relatives (carriers, affected males)

Tertiary Prevention (Preventing Complications)

Nephrolithiasis prevention: hydration, citrate, moderate sodium
Bone health: vitamin D, phosphate as needed
CKD progression: avoid nephrotoxins, treat hypertension if present
Growth: GH supplementation in select DD2 pediatric cases

Immunization

Routine (no disease-specific vaccines).

Screening / Early Detection

Japan's routine school-age urine screening program has identified pediatric DD cases (contributes to Japan having one of the largest published cohorts).
Newborn genomic screening pilots (e.g., BabySeq) may identify neonatal DD.

Counseling

Genetic counseling essential for affected males and carrier females; recurrence risk 50% per pregnancy in carrier mothers.

Public Health / Environmental

Public health measures (hydration, dietary sodium) reduce stone burden.
Occupational nephrotoxin awareness for affected individuals.

14. Other Species / Natural Disease

Taxonomy

Human (Homo sapiens; NCBITaxon:9606) — natural host
Naturally occurring Dent-like disease in non-human animals is not documented.

Comparative Biology / Orthology

Mouse (Mus musculus; NCBITaxon:10090): Clcn5 gene (NCBI Gene ID:12728); functional ortholog
Rat (Rattus norvegicus): Clcn5 (Gene ID:29232)
Zebrafish (Danio rerio; NCBITaxon:7955): clcn5 (Gene ID:559898); ocrl (Gene ID:436692)
Drosophila (D. melanogaster): ClC-a (functional homolog used in a DD1 model, 2026)
OCRL orthologs are highly conserved across metazoans and share a paralog (INPP5B) in mammals.

Zoonotic / Cross-Species Transmission

Not applicable — Dent disease is monogenic and non-communicable.

Veterinary Relevance

No natural Dent disease is described in companion animals; the disease exists only as engineered model in laboratory species.

15. Model Organisms

Mouse Models

Clcn5⁻/y knockout (Piwon et al., 2000, PMID:11099045) — Nature: recapitulates LMWP, generalized aminoaciduria, glycosuria, hypercalciuria; impaired proximal tubular endocytosis of horseradish peroxidase.
Clcn5 knockout (Wang et al., 2000, PMID:11115835) — Hum Mol Genet: independent line, same phenotype; loss of megalin/cubilin at brush border.
Clcn5 knock-in (E211A, exchanger-to-channel conversion; Novarino et al., 2010) — normal endosomal acidification but abnormal endosomal Cl⁻, still recapitulates renal phenotype, arguing that luminal Cl⁻ accumulation, not just acidification, is essential.
Novel transgenic Clcn5 model (2024, PMID:39019097) — highlights disrupted autophagy and endolysosomal molecular disruptions.
Ocrl⁻/⁻ mice: Ocrl KO mice are unexpectedly asymptomatic (compensation by Inpp5b); Ocrl/Inpp5b double-KO is embryonic lethal.

Zebrafish

ocrl morphants and mutants: shortened pronephros, defective endocytosis, neurodevelopmental defects (2025, PMID:40778266) — useful for high-throughput drug screening for Dent-2 and Lowe syndrome.

Drosophila

DD1 model (Kidney International, 2026, PMID:41690574): implicates impaired ER export of Cubilin as a pathogenic mechanism, opening a new therapeutic angle.

Cellular Models

CLCN5-KO HK-2 cells and PT cell lines (Gorvin et al., 2013; Perego et al., 2021, PMID:33710298) — reveal transcriptomic dysregulation in endocytic, lipid, and autophagy pathways.
iPSC-derived kidney organoids — emerging models but published DD-specific data limited.
Human primary PT-cell lines from DD1 patient urine (De Matteis, Devuyst labs) — recapitulate megalin/cubilin mislocalization and endocytic dysfunction (Gorvin 2013).

Applications

Testing endocytic rescue strategies
Screening small-molecule chaperones for Class-1 misfolded ClC-5
Testing AAV gene addition
Evaluating dietary and pharmacologic interventions (high citrate, thiazides)

Model Limitations

Ocrl-KO mice do not model human DD2 due to Inpp5b compensation
CKD progression in Clcn5-KO mice occurs later and slower than in humans
No non-human model spontaneously recapitulates both nephrocalcinosis and progressive ESKD reliably

Resources

MGI (Clcn5): MGI:99486
RGD (Clcn5): RGD:2381
ZFIN (clcn5): ZDB-GENE-030228-6
IMPC, KOMP, EMMA repositories house available knockout strains

Selected Key References (with PMIDs)

Dent CE, Friedman M. (1964). Hypercalciuric rickets associated with renal tubular damage. Arch Dis Child. PMID:14158899
Piwon N, et al. (2000). ClC-5 Cl-channel disruption impairs endocytosis in a mouse model for Dent's disease. Nature 408:369-73. PMID:11099045
Wang SS, et al. (2000). Mice lacking renal chloride channel, CLC-5, are a model for Dent's disease. Hum Mol Genet 9:2937-45. PMID:11115835
Christensen EI, et al. (2003). Loss of chloride channel ClC-5 impairs endocytosis by defective trafficking of megalin and cubilin. PNAS 100:8472-7. PMID:12815099
Cebotaru V, et al. (2005). High citrate diet delays progression of renal insufficiency in the ClC-5 knockout mouse model. Kidney Int 68:642-52. PMID:16014041
Grand T, et al. (2009). Characterization of Dent's disease mutations of CLC-5 reveals a correlation between functional and cell biological consequences. Hum Mol Genet 18:4457-71. PMID:19019917
Devuyst O, Thakker RV. (2010). Dent's disease. Orphanet J Rare Dis 5:28. PMID:20946626
Copelovitch L, et al. (2015). Nephrotic-range albuminuria as the presenting symptom of Dent-2 disease. Ital J Pediatr 41:31. PMID:26154403
Wang X, et al. (2016). Glomerular Pathology in Dent Disease and Its Association with Kidney Function. Clin J Am Soc Nephrol 11:2168-76. PMID:27697782
Bhardwaj S, et al. (2021). Dent Disease. GeneReviews (updated). NBK99494
Gianesello L, et al. (2021). Genotype-Phenotype Correlation in Dent Disease 2 and Review of the Literature: OCRL Gene Pleiotropism or Extreme Phenotypic Variability of Lowe Syndrome? Genes 12:1597. PMID:34680992
Perego C, et al. (2021). Novel Dent disease 1 cellular models reveal biological processes underlying ClC-5 loss-of-function. Hum Mol Genet 30:1413-1428. PMID:33710298
Blanchard A, et al. (2025). Dent disease: clinical practice recommendations. Nephrol Dial Transplant 40:852-864. PMID:39794284
Lu B, et al. (2026). Database of CLCN5 Pathogenic Variants Causing Dent Disease. Kidney International Reports. DOI:10.1016/j.ekir.2026.106475
(2024). A novel transgenic mouse model highlights molecular disruptions involved in the pathogenesis of Dent disease 1. PMID:39019097
(2026). A Drosophila model for Dent's disease type 1 revealed impaired endoplasmic reticulum export of Cubilin as pathogenic mechanism. Kidney Int. PMID:41690574
Bailey MA. (2015). Hydrochlorothiazide-induced tubulointerstitial nephritis in a patient with Dent disease. PMID:25911330

Suggested Ontology Term Bindings for the KB Entry

Field	Term	ID
disease_term (group)	Dent disease	MONDO:0015612
Dent disease 1	Dent disease 1	MONDO:0010655
Dent disease 2	Dent disease 2	MONDO:0010371
Causal gene 1	CLCN5	hgnc:2023
Causal gene 2	OCRL	hgnc:8108
Inheritance	X-linked recessive inheritance	HP:0001419
Cell type	kidney proximal convoluted tubule epithelial cell	CL:1000838
Anatomy	renal proximal tubule	UBERON:0004134
Anatomy	kidney cortex	UBERON:0001225
Subcellular	early endosome	GO:0005769
Process	receptor-mediated endocytosis	GO:0006898
Process	endosomal acidification	GO:0048388
Process	phosphatidylinositol dephosphorylation	GO:0046856
Phenotype	Low molecular weight proteinuria	HP:0003126
Phenotype	Hypercalciuria	HP:0002150
Phenotype	Nephrocalcinosis	HP:0000121
Phenotype	Nephrolithiasis	HP:0000787
Phenotype	Chronic kidney disease	HP:0012622
Phenotype	Rickets	HP:0002748
Phenotype	Hypophosphatemia	HP:0002148
Phenotype	Aminoaciduria	HP:0003355
Treatment	Potassium citrate	CHEBI:32029
Treatment	Hydrochlorothiazide	CHEBI:5778
Treatment	Kidney transplantation	NCIT:C15289
Treatment	Pharmacotherapy	NCIT:C15986

Sources

Sources: - Dent disease: clinical practice recommendations (Oxford NDT, 2025) - Dent's disease — Orphanet review, Devuyst & Thakker 2010 (PMC) - Dent Disease — GeneReviews (NCBI) - Database of CLCN5 Pathogenic Variants Causing Dent Disease (Lu et al., 2026) - Genotype-Phenotype Correlation in Dent Disease 2 (Gianesello 2021) - ClC-5 Cl-channel disruption impairs endocytosis (Piwon 2000, PubMed) - Mice lacking renal chloride channel CLC-5 (Wang 2000) - Loss of ClC-5 impairs endocytosis by defective trafficking of megalin and cubilin (PNAS) - High citrate diet delays progression in Clcn5-KO mice (Cebotaru 2005) - Responsiveness of Hypercalciuria to Thiazide in Dent's Disease (JASN 2002) - Effect of hydrochlorothiazide on urinary calcium excretion in Dent disease (Blanchard 2008) - Glomerular Pathology in Dent Disease and Its Association with Kidney Function (Wang 2016) - Novel Dent disease 1 cellular models (Perego 2021) - Nephrotic-range albuminuria in Dent-2 disease (Copelovitch 2015) - Modelling Lowe syndrome and Dent-2 disease using zebrafish (2025) - Drosophila model for Dent's disease type 1 (2026) - A novel transgenic mouse model of Dent disease 1 (2024) - Phenotype and genotype analyses of 21 Chinese patients with Dent disease - Clinical features and genetic analysis of 9 Chinese children with Dent disease (2025) - Dent Disease 2 as a Cause of Focal Segmental Glomerulosclerosis (Case Report) - Hydrochlorothiazide-induced tubulointerstitial nephritis in Dent disease (Bailey 2015) - Nephrolithiasis, kidney failure and bone disorders in Dent disease (Blanchard et al.) - Genotype-Phenotype Correlation in Dent Disease Type 1 (Kidney Int Reports) - OMIM Dent Disease 1 #300009 - OMIM Dent Disease 2 #300555 - Novel OCRL isoforms and phenotypic differences DD2/Lowe (NDT 2022) - UpToDate — Dent disease (X-linked recessive nephrolithiasis) - GARD — Dent disease

Reference Validation

Checked with linkml-reference-validator 0.2.1.

Outcome	Count
References checked	35
Resolved	35
Unresolved (possible confabulation)	0
Unverifiable	0
References weighed for topical relevance	35
On topic	21
Off topic	5

References that may not be about this subject

These identifiers resolve, so they are not fabrications, but the records they resolve to share almost none of this report's vocabulary. That is a clue and not a verdict - a paper can be relevant in ways its title and abstract do not spell out - so read them before deciding:

PMID:20950533 (1 mention) - Training for and dissemination of the Nutrition Environment Measures Surveys (NEMS).
shared terms: none
PMID:26296266 (1 mention) - Change in waist circumference with longer time in the United States among Hispanic and Chinese immigrants: the modifying role of the neighborhood built environment.
shared terms: model
PMID:26154403 (2 mentions) - Aerobic Nickel-Catalyzed Hydroxysulfonylation of Alkenes Using Sodium Sulfinates.
shared terms: none
PMID:11279143 (1 mention) - Centrosome protein centrin 2/caltractin 1 is part of the xeroderma pigmentosum group C complex that initiates global genome nucleotide excision repair.
shared terms: gene
PMID:25911330 (2 mentions) - The Clinical Use of Genomic Profiling to Distinguish Intrapulmonary Metastases From Synchronous Primaries in Non-Small-Cell Lung Cancer: A Mini-Review.
shared terms: genetic

Weighed against this report's own most characteristic terms: disease, clcn5, ocrl, kidney, renal, hypercalciuria, dent, variant, dd2, genetic, phenotype, nephrocalcinosis, model, gene, blanchard, dd1, ckd, ricket, clc-5, stone.

All extracted references resolved successfully. Resolving is not the same as being relevant, though - see the references listed above as possibly off topic.

Term Validation

Checked with linkml-term-validator 0.4.5, through the ols: adapter.

Outcome	Count
Terms checked	61
Resolved	50
Unresolved (possible confabulation)	0
Obsolete	0
Unverifiable	11
Terms whose name was checked	43
Terms named correctly	26
Terms named as a different term	5
Terms whose name is worth a second look	12

Terms the report names something else

These identifiers resolve, so nothing about them looks wrong, and the ontology calls them something unrelated to what the report calls them. That usually means the identifier is not the one the sentence needs:

MONDO:0010655 (2 mentions) - the report calls it "MONDO (DD1)", "Dent disease 1"; MONDO calls it X-linked intellectual disability with marfanoid habitus
MONDO:0010371 (2 mentions) - the report calls it "MONDO (DD2)", "Dent disease 2"; MONDO calls it Aland island eye disease
HP:0000790 (1 mention) - the report calls it "Hematuria (usually microscopic)"; HP calls it Hematuria
HP:0032122 (1 mention) - the report calls it "Elevated β2-microglobulin, α1-microglobulin"; HP calls it Very low visual acuity
UBERON:0001225 (2 mentions) - the report calls it "Primary: Kidney — specifically the renal cortex", "kidney cortex"; UBERON calls it cortex of kidney**

Terms whose name is worth a second look

The report's name for these is recognisably related to the term's own name without being one of them. A loose paraphrase reads the same way as a citation of the wrong sibling term - and so does a related synonym, which the ontology records precisely because it names something adjacent rather than the same thing - so these are listed rather than judged:

MONDO:0015612 (3 mentions) - the report calls it "Dent disease group", "Dent disease"; MONDO calls it Dent disease, and lists "Dent disease 1" among its other names
HP:0000787 (2 mentions) - the report calls it "Nephrolithiasis (kidney stones)", "Nephrolithiasis"; HP calls it Kidney stone, and lists "Nephrolithiasis" among its other names
HP:0025435 (1 mention) - the report calls it "Elevated lactate dehydrogenase"; HP calls it Increased circulating lactate dehydrogenase concentration, and lists "Increased lactate dehydrogenase level" among its other names
HP:0001252 (1 mention) - the report calls it "Muscle weakness / hypotonia"; HP calls it Hypotonia, and lists "Muscle hypotonia" among its other names
HP:0000518 (1 mention) - the report calls it "Cataracts (rare)"; HP calls it Cataract, and lists "Cataracts" among its other names
GO:0008286 (1 mention) - the report calls it "insulin receptor-signaling – megalin cargo"; GO calls it insulin receptor signaling pathway
GO:0006874 (1 mention) - the report calls it "cellular calcium ion homeostasis"; GO calls it intracellular calcium ion homeostasis, and lists "cellular calcium ion homeostasis" among its other names
UBERON:0004134 (2 mentions) - the report calls it "Renal proximal tubule", "renal proximal tubule"; UBERON calls it proximal tubule, and lists "renal proximal tubule" among its other names
CL:1000838 (2 mentions) - the report calls it "Renal proximal convoluted tubule cell", "kidney proximal convoluted tubule epithelial cell"; CL calls it kidney proximal convoluted tubule epithelial cell
CHEBI:32029 (2 mentions) - the report calls it "Potassium citrate"; CHEBI calls it potassium acetate
NCIT:C15289 (2 mentions) - the report calls it "Kidney transplantation"; NCIT calls it Organ Transplantation
GO:0048388 (1 mention) - the report calls it "endosomal acidification"; GO calls it endosomal lumen acidification

Terms named inconsistently

The report gives these identifiers more than one name of its own:

MONDO:0015612 - called "Dent disease group", "Dent disease"
MONDO:0010655 - called "MONDO (DD1)", "Dent disease 1"
MONDO:0010371 - called "MONDO (DD2)", "Dent disease 2"
HP:0003126 - called "Low-molecular-weight proteinuria", "Low molecular weight proteinuria"
HP:0000787 - called "Nephrolithiasis (kidney stones)", "Nephrolithiasis"
UBERON:0001225 - called "Primary:** Kidney — specifically the renal cortex", "kidney cortex"
UBERON:0004134 - called "Renal proximal tubule", "renal proximal tubule"
CL:1000838 - called "Renal proximal convoluted tubule cell", "kidney proximal convoluted tubule epithelial cell"

Prefixes with no resolver

Terms carrying these prefixes were not checked either way, because no configured ontology covers them. An unrecognised prefix may name an ontology this run could not reach as easily as one that does not exist, so nothing here is evidence of fabrication: ORPHA, LOINC, ID, MGI, RGD.

Ask OpenScientist

OpenScientist Report

Classifications

Definitions

Inheritance

Subtypes

Discussions and Knowledge Gaps

Pathophysiology

Pathograph

Phenotypes

Genetic Associations

Medical Actions

Diagnosis

Progression

Prevalence

Differential Diagnoses

Animal Models

Source YAML

References & Deep Research

References

Deep Research

Dent Disease: Comprehensive Research Report

1. Disease Information

Overview

Key Identifiers

Synonyms / Alternative Names

Data Derivation

2. Etiology

Disease Causal Factors

Risk Factors

Protective Factors

Gene-Environment Interactions

3. Phenotypes

Core Renal Phenotypes (with HPO term suggestions and frequencies)

DD2-Specific Extra-Renal Phenotypes (from OCRL mutations)

Phenotype Characteristics

"Nephrotic-Range" Proteinuria Pitfall

4. Genetic / Molecular Information

Causal Genes

Pathogenic Variants

Variant Classification

Allele Frequency

Somatic vs. Germline

Functional Consequences

Modifier Genes

Epigenetic Information

Chromosomal Abnormalities

5. Environmental Information

6. Mechanism / Pathophysiology

Ordered Causal Chain (DD1, CLCN5-related)

Ordered Causal Chain (DD2, OCRL-related)

Molecular Pathways

Cellular Processes

Protein Dysfunction

Metabolic / Biochemical Abnormalities

Tissue Damage Mechanisms

Immune / Inflammation

Molecular Profiling

Advanced Technologies

7. Anatomical Structures Affected

Organ Level

Tissue and Cell Level

Subcellular Level

Anatomical Localization

8. Temporal Development

Onset

Progression

Age Distribution of Kidney Failure

Critical Periods

9. Inheritance and Population

Epidemiology

Inheritance

Population Demographics

10. Diagnostics

Clinical Tests

Imaging

Pathology (biopsy findings)

Genetic Testing

Clinical Diagnostic Criteria (2010 / reaffirmed 2025)

Differential Diagnosis