IEMbase 0525: CTNS-related nephropathic cystinosis
Scope
| Field | Value |
|---|---|
| IEMbase ID | 525 |
| Nosology | 1.11.01.02 |
| Gene | CTNS |
| External IDs | OMIM:219800; OMIM:219900; OMIM:219750; ORPHA:411634 |
| Generated mapping | AMBIGUOUS; identifier match on OMIM:219750 |
| Candidate DisMech targets | Cystinosis.yaml; Cystinosis.yaml#Non-nephropathic ocular cystinosis |
| Review date | 2026-07-07 |
IEMbase phenotype signal
IEMbase represents this as CTNS-related nephropathic cystinosis, with juvenile cystinosis and CTNS as alternate labels. The record is autosomal recessive, treatability is marked yes, and treatment rows list oral cysteamine bitartrate and cysteamine eyedrops.
The characteristic biochemical rows include increased cystine in fibroblasts and white blood cells, aminoaciduria, urinary losses of albumin, glucose, phosphate, potassium, sodium, calcium, and uric acid, low plasma bicarbonate, low plasma phosphate, low plasma potassium, and low or normal free carnitine. Clinical rows emphasize renal Fanconi syndrome, chronic renal failure, polyuria, rickets, renal osteodystrophy, nephrocalcinosis/nephrolithiasis, failure to thrive, corneal cystine crystals, photophobia, retinopathy, hypogonadism, male infertility, hypothyroidism, diabetes, myopathy, swallowing difficulty, and later neurologic involvement.
DisMech phenotype coverage
Cystinosis.yaml is the correct local target, but the generated mapping is
ambiguous because the IEMbase row carries the ocular-cystinosis OMIM identifier
alongside nephropathic infantile and juvenile identifiers. The local file
explicitly models CTNS lysosomal cystine transporter deficiency and has
nephropathic infantile, nephropathic juvenile, and non-nephropathic ocular
subtypes.
Local coverage is strong for CTNS/cystinosin biology, lysosomal cystine accumulation, proximal tubule dysfunction, renal Fanconi syndrome, progressive kidney disease, corneal crystal disease, oral and ophthalmic cysteamine, and replacement therapy for Fanconi losses.
Concordance and completeness
Judgement: correct local cystinosis target; manually resolve the ambiguity to the nephropathic cystinosis context rather than the ocular-only subtype.
IEMbase and DisMech agree on CTNS, lysosomal cystine storage, autosomal recessive inheritance, Fanconi syndrome, renal progression, corneal crystals, photophobia, and cysteamine therapy. IEMbase is useful as a detailed analyte checklist for tubular solute wasting and extrarenal late manifestations.
Curation actions
- Keep this record mapped to
Cystinosis.yaml, with nephropathic infantile and juvenile subtype context. - Do not use OMIM:219750 alone to collapse this record to ocular cystinosis.
- Preserve the IEMbase renal-wasting analytes, free-carnitine row, endocrine, gonadal, ocular, myopathy, swallowing, and neurologic prompts for future review.