Camurati-Engelmann Disease

Mendelian MONDO:0007542 Pathograph 25 Sclerosing Bone Dysplasias

Camurati-Engelmann disease (CED), also known as progressive diaphyseal dysplasia, is an autosomal dominant sclerosing bone disorder caused by mutations in TGFB1 encoding transforming growth factor beta 1. It is characterized by progressive cortical thickening (hyperostosis) of the diaphyses of long bones, leading to limb pain, muscle weakness, waddling gait, and easy fatigability. Skull involvement can cause cranial nerve palsies, particularly facial nerve paralysis and hearing loss. The disease typically presents in childhood and shows variable expressivity.

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1
Inheritance
3
Pathophys.
11
Phenotypes
25
Pathograph
1
Genes
8
Treatments
10
References
2
Deep Research
👪

Inheritance

1
Autosomal Dominant HP:0000006
Autosomal dominant inheritance with variable expressivity and incomplete penetrance. Some mutation carriers remain asymptomatic.
Autosomal dominant inheritance Penetrance: INCOMPLETE Expressivity: VARIABLE
Show evidence (2 references)
PMID:15326622 SUPPORT
"This pedigree demonstrates the autosomal dominant inheritance pattern, remarkable variation in expressivity, and reduced penetrance."
Four-generation pedigree showing variable expressivity, with an asymptomatic obligate carrier into his ninth decade.
PMID:15894597 SUPPORT
"Radiological symptoms were not fully penetrant, with 94% of the patients showing the typical long bone involvement."
In 100 molecularly confirmed cases, radiological features were not fully penetrant, demonstrating variable expressivity.
⚙

Pathophysiology

3
Constitutive TGF-beta 1 Activation
Mutations in TGFB1 affect the latency-associated peptide (LAP) region, disrupting the non-covalent association between LAP and mature TGF-beta 1. This leads to premature or excessive release of active TGF-beta 1 from its latent complex, resulting in increased osteoblast activity and cortical bone thickening in the diaphyses.
Osteoblast link Osteoclast link
TGF-beta Signaling link Bone Remodeling link Osteoblast Differentiation link
Downstream
Rho GTPase-Mediated Osteoclast Activation Excess active TGF-beta 1 engages non-canonical Rho GTPase signaling that increases osteoclast formation, migration, and resorptive activity.
Impaired Bone Remodeling Balance Overactive TGF-beta signaling disrupts coordinated bone formation and resorption, producing high-turnover cortical sclerosis.
Show evidence (3 references)
PMID:11278244 SUPPORT
"these mutations disrupt the association of beta1-LAP and TGF-beta1 and the subsequent release of the mature TGF-beta1"
Functional studies showed CED-causing LAP mutations (R218H, R218C, C225R) disrupt LAP-TGF-beta1 association, leading to constitutive activation of TGF-beta 1.
PMID:11278244 SUPPORT In Vitro
"the proliferation of human osteoblastic MG-63 cells was accelerated by coculture with CED fibroblasts"
Demonstrates increased osteoblast activity driven by excess TGF-beta 1 release from CED patient fibroblasts.
PMID:30721323 SUPPORT Other
"disease-causing mutations are located within the TGFβ-1 gene and expected to or thought to disrupt the binding between TGFβ1 and its latency-associated peptide resulting in an increased signaling of the pathway and subsequently accelerated bone turnover."
A contemporary review summarizes the TGFB1 LAP-restraint mechanism and links increased signaling to accelerated bone turnover.
Rho GTPase-Mediated Osteoclast Activation
Aberrant TGF-beta 1 signaling activates non-canonical Rho GTPase pathways in osteoclast-lineage cells. This increases osteoclastogenesis, migration, bone resorption, and cytoskeletal remodeling, providing a disease-specific branch from TGFB1 activation to high-turnover cortical sclerosis.
Osteoclast link
Rho protein signal transduction link osteoclast differentiation link bone resorption link
Downstream
Impaired Bone Remodeling Balance Increased osteoclast formation and resorption contribute to uncoupled high-turnover bone remodeling.
Show evidence (2 references)
DOI:10.3389/fendo.2022.913979 SUPPORT In Vitro
"activation of Rho by TGF-β1 increased osteoclast formation and bone resorption, with increased migration of pre-osteoclasts, as well as cytoskeletal remodeling of pre-osteoclasts and mature osteoclasts."
Cell-based functional evidence supports a non-canonical TGF-beta/Rho osteoclast branch that promotes high-turnover remodeling in CED.
DOI:10.3389/fendo.2022.913979 SUPPORT In Vitro
"pharmacological inhibition of Rho GTPases effectively rescued hyperactive TGF-β1-induced osteoclastogenesis in vitro."
Rescue with Rho inhibition supports Rho GTPase signaling as a causal modifier of TGF-beta-driven osteoclastogenesis.
Impaired Bone Remodeling Balance
Excessive TGF-beta 1 signaling shifts the balance between bone formation and resorption toward increased periosteal and endosteal new bone formation. The resulting cortical thickening narrows the medullary cavity of long bones, contributing to marrow failure and pain.
Osteoblast link Osteoclast link
Ossification link Bone remodeling link
Diaphysis link Medullary cavity of long bone link
Downstream
Diaphyseal Dysplasia Periosteal and endosteal new bone formation produces progressive diaphyseal hyperostosis and sclerosis.
Stenosis of the Medullary Cavity Endosteal cortical thickening narrows the medullary cavity of long bones.
Limb Pain High-turnover cortical remodeling and narrowed marrow spaces contribute to bone pain.
Skull Involvement The same hyperostotic remodeling can involve the skull and skull base.
Cranial Nerve Palsy Skull-base hyperostosis can narrow foramina and compress cranial nerves.
Increased Intracranial Pressure Severe cranial involvement can cause intracranial-pressure complications.
Show evidence (2 references)
PMID:10973241 SUPPORT
"Camurati-Engelmann disease (CED, MIM 131300) is an autosomal dominant, progressive diaphyseal dysplasia characterized by hyperosteosis and sclerosis of the diaphyses of long bones."
Landmark paper identifying TGFB1 as the CED gene and describing the characteristic diaphyseal hyperostosis and sclerosis.
DOI:10.1159/000479859 SUPPORT Human Clinical
"Cortical thickening of the diaphyses of the long bones with narrowing of the medullary cavity are associated with bone pain, waddling gait, muscular weakness, easy fatigability, and a marfanoid body habitus."
Clinical treatment-report background links diaphyseal cortical thickening and medullary narrowing to the core CED clinical phenotype.
⬡

Pathograph

Use the checkboxes to hide or show graph categories. Hover nodes for evidence and cross-linked metadata.
Pathograph: causal mechanism network for Camurati-Engelmann Disease Interactive directed graph showing how pathophysiology mechanisms, phenotypes, genetic factors and variants, experimental models, environmental triggers, and treatments relate through causal and linked edges.
●

Phenotypes

11
Ear 1
Hearing Loss Hearing impairment (HP:0000365)
Show evidence (1 reference)
PMID:20301335 SUPPORT Other
"Management of hearing loss per otolaryngologist; bilateral myringotomy can improve conductive hearing loss resulting from serous otitis."
GeneReviews supports hearing loss as a managed manifestation of CED and notes conductive hearing loss in some individuals.
Eye 1
Exophthalmos Proptosis (HP:0000520)
Show evidence (1 reference)
PMID:20301335 SUPPORT Other
"Facial features such as macrocephaly, frontal bossing, enlargement of the mandible, proptosis, and cranial nerve impingement resulting in facial palsy are seen in severely affected individuals later in life."
GeneReviews directly includes proptosis among severe CED manifestations.
Head and Neck 1
Skull Involvement Cranial hyperostosis (HP:0004437)
Show evidence (1 reference)
PMID:15894597 SUPPORT
"A large percentage of the patients also showed involvement of the skull (54%) and pelvis (63%)."
Skull involvement documented in 54% of 100 molecularly confirmed CED patients.
Integument 1
Reduced Subcutaneous Fat Minimal subcutaneous fat (HP:0003717)
Show evidence (1 reference)
PMID:25140400 SUPPORT
"There was also a considerable improvement in body composition with increased lean and adipose tissue. Notably, the improvement in fat deposition had not been previously observed with other treatments in CED."
Losartan treatment improved fat deposition, confirming that reduced subcutaneous fat is a recognized feature of CED.
Limbs 1
Diaphyseal Dysplasia Diaphyseal dysplasia (HP:0100252)
Show evidence (1 reference)
PMID:15894597 SUPPORT
"Radiological symptoms were not fully penetrant, with 94% of the patients showing the typical long bone involvement."
In 100 molecularly confirmed CED patients from 24 families, 94% showed characteristic long bone diaphyseal involvement.
Musculoskeletal 1
Muscle Weakness Muscle weakness (HP:0001324)
Show evidence (1 reference)
PMID:15894597 SUPPORT
"easy fatigability (44%), and muscle weakness (39%) were other important features."
Muscle weakness (39%) and easy fatigability (44%) were documented as prominent clinical features in 100 CED patients.
Nervous System 3
Waddling Gait Waddling gait (HP:0002515)
Show evidence (1 reference)
PMID:15894597 SUPPORT
"A waddling gait (48%), easy fatigability (44%), and muscle weakness (39%) were other important features."
Waddling gait was present in 48% of molecularly confirmed CED patients.
Cranial Nerve Palsy Cranial nerve compression (HP:0001293)
Show evidence (2 references)
PMID:15326622 SUPPORT
"Cranial involvement, which occurs in 61% of patients, can be severe, entrapping cranial nerves or causing increased intracranial pressure."
Literature review found cranial involvement in 61% of CED patients, with potential for cranial nerve entrapment.
PMID:15326622 SUPPORT
"The most severely affected individual had progression of mild skull hyperostosis to severe skull thickening and cranial nerve compression over 30 years."
Documents progressive cranial nerve compression from skull hyperostosis over decades.
Increased Intracranial Pressure Increased intracranial pressure (HP:0002516)
Show evidence (1 reference)
PMID:15326622 SUPPORT Human Clinical
"Cranial involvement, which occurs in 61% of patients, can be severe, entrapping cranial nerves or causing increased intracranial pressure."
The review directly supports intracranial-pressure complications in severe cranial CED.
Constitutional 1
Limb Pain Limb pain (HP:0009763)
Show evidence (2 references)
PMID:15894597 SUPPORT
"Pain in the extremities was the most common clinical symptom, present in 68% of the patients."
Limb pain was the most frequent symptom in a large review of 100 molecularly confirmed CED patients.
PMID:15326622 SUPPORT
"Symptomatic relatives presented with lower limb pain and weakness."
Four-generation pedigree confirms lower limb pain as a presenting feature.
Other 1
Stenosis of the Medullary Cavity Stenosis of the medullary cavity of the long bones (HP:0100254)
Show evidence (1 reference)
DOI:10.1159/000479859 SUPPORT Human Clinical
"Cortical thickening of the diaphyses of the long bones with narrowing of the medullary cavity are associated with bone pain, waddling gait, muscular weakness, easy fatigability, and a marfanoid body habitus."
The abstract directly supports medullary-cavity narrowing as part of the CED long-bone phenotype.
🧬

Genetic Associations

1
TGFB1 Mutations (Causative)
Show evidence (4 references)
PMID:10973241 SUPPORT
"As the human transforming growth factor-1 gene (TGFB1) is located within this interval, we considered it a candidate gene for CED."
Landmark paper identifying TGFB1 as the causative gene for CED, with mutations in the 19q13 region.
PMID:11062463 SUPPORT
"this region contains the gene encoding transforming growth factor-beta 1 (TGFB1), an important mediator of bone remodelling, we evaluated TGFB1 as a candidate gene for causing CED."
Independent identification of TGFB1 LAP domain mutations as the cause of CED.
PMID:11278244 SUPPORT
"three different missense mutations (R218H, R218C, and C225R) of beta1-LAP cause the Camurati-Engelmann disease (CED)"
Functional characterization of the three most common LAP mutations, confirming they cause constitutive TGF-beta1 activation.
+ 1 more reference
💊

Treatments

8
Corticosteroid Therapy
Action: pharmacotherapy MAXO:0000058
Low-dose corticosteroids (deflazacort or prednisone) are the mainstay of treatment. They reduce bone pain and improve muscle weakness, likely through anti-inflammatory effects and suppression of TGF-beta 1 signaling.
Target Phenotypes: Limb pain ↗ Muscle weakness ↗
Show evidence (4 references)
PMID:20301335 SUPPORT Other
"Corticosteroid therapy as needed to control symptoms; losartan may be a helpful adjuvant therapy to minimize the need for steroids to control pain."
GeneReviews supports corticosteroids as targeted symptomatic therapy and frames losartan as an adjuvant pain-control option.
PMID:11278244 SUPPORT In Vitro
"The growth suppression observed was attenuated by neutralizing antibody to TGF-beta1 or by treatment of dexamethasone."
In vitro evidence that dexamethasone attenuates TGF-beta1-mediated growth effects, providing a mechanistic rationale for corticosteroid therapy in CED.
PMID:15326622 SUPPORT
"Two of the symptomatic individuals were treated successfully with prednisone."
Clinical report of successful prednisone treatment in CED patients.
+ 1 more reference
Losartan
Action: pharmacotherapy MAXO:0000058
Agent: losartan ↗
Angiotensin receptor blockers have been investigated as TGF-beta pathway modulators. Losartan has shown clinical benefit in eliminating pain and improving exercise capacity and body composition.
Target Phenotypes: Limb pain ↗
Show evidence (3 references)
PMID:20301335 SUPPORT Other
"losartan may be a helpful adjuvant therapy to minimize the need for steroids to control pain."
GeneReviews supports losartan as an adjuvant targeted therapy for pain control in CED.
PMID:25140400 SUPPORT
"losartan treatment led to the complete elimination of the previously severe and incapacitating pain, with an increased ability to walk and perform physical activities."
Case report showing losartan completely eliminated pain and improved exercise capacity in a 9-year-old CED patient.
PMID:25140400 SUPPORT
"In light of our findings, losartan may be a useful option in CED management."
Authors conclude losartan is a promising treatment option for CED.
Zoledronic Acid for Severe CED
Action: pharmacotherapy MAXO:0000058
Bisphosphonate therapy with zoledronic acid is not established first-line CED care, but severe case reports describe improvement in pain, ambulation, bone lesions, body habitus, and bone-turnover markers.
Target Phenotypes: Limb pain ↗ Stenosis of the medullary cavity of the long bones ↗
Show evidence (2 references)
DOI:10.1159/000479859 SUPPORT Human Clinical
"In both probands, zoledronic acid treatment significantly improved the clinical symptoms, bone lesions, ambulation, and body habitus."
Case-based clinical evidence supports zoledronic acid as a lower-evidence severe-CED therapeutic option.
DOI:10.1159/000479859 SUPPORT Human Clinical
"Zoledronic acid treatment may be an important therapeutic option in patients with severe CED."
The authors explicitly frame zoledronic acid as a potential option for severe disease rather than a general standard of care.
Analgesic Therapy
Action: supportive care MAXO:0000950
Pain management with NSAIDs and analgesics for symptomatic relief.
Target Phenotypes: Limb pain ↗
Show evidence (1 reference)
PMID:20301335 SUPPORT Other
"pain is also managed with analgesics, non-pharmacologic methods, and on occasion surgical treatment."
GeneReviews supports analgesic and non-pharmacologic pain management.
Physical Therapy and Mobility Support
Action: physical therapy MAXO:0000011
Physical medicine, physical therapy, adaptive devices, and fall precautions address weakness, gait impairment, contractures, and functional mobility.
Target Phenotypes: Muscle weakness ↗ Waddling gait ↗
Show evidence (1 reference)
PMID:20301335 SUPPORT Other
"Management of muscle weakness and gait issues per physical medicine and rehabilitation specialists and physical therapist."
GeneReviews supports physical medicine and physical therapy for weakness and gait issues.
Audiology and Otolaryngology Care
Action: audiologist evaluation MAXO:0000734
Annual audiology and otolaryngology care monitor and manage hearing loss; myringotomy may help conductive hearing loss from serous otitis.
Target Phenotypes: Hearing impairment ↗
Show evidence (2 references)
PMID:20301335 SUPPORT Other
"Management of hearing loss per otolaryngologist; bilateral myringotomy can improve conductive hearing loss resulting from serous otitis."
GeneReviews supports specialty hearing management and a conductive-hearing intervention when serous otitis is present.
PMID:20301335 SUPPORT Other
"annual audiology evaluation with BAER and inner ear CT as needed;"
GeneReviews supports annual audiology surveillance.
Ophthalmology and Intracranial Pressure Management
Action: ophthalmologist evaluation MAXO:0000703
Ophthalmic subspecialty care, low vision services, and neurosurgical decompression when needed address ocular manifestations and raised intracranial pressure from severe cranial sclerosis.
Target Phenotypes: Proptosis ↗ Increased intracranial pressure ↗
Show evidence (1 reference)
PMID:20301335 SUPPORT Other
"Treatment of ocular manifestations per ophthalmic subspecialist with low vision services as needed; craniectomy may be needed to reduce intracranial pressure"
GeneReviews supports ophthalmology care and decompressive surgery for pressure complications in severe cranial disease.
Bone Density, Blood Count, and Disease Activity Monitoring
Action: supportive care MAXO:0000950
Monitor musculoskeletal disease activity, corticosteroid-related bone density risk, blood pressure during targeted therapy, and annual CBC for marrow consequences of medullary-cavity narrowing.
Target Phenotypes: Stenosis of the medullary cavity of the long bones ↗
Show evidence (2 references)
PMID:20301335 SUPPORT Other
"serum ESR and bone scan as needed in those with acute bone pain to assess disease activity; evaluation of bone mineral density annually in those treated with corticosteroids;"
GeneReviews supports disease-activity and bone-density monitoring.
PMID:20301335 SUPPORT Other
"assess blood pressure at each visit; annual CBC."
GeneReviews supports blood-pressure and blood-count surveillance.
{ }

Source YAML

click to show 
name: Camurati-Engelmann Disease
creation_date: '2026-02-13T00:31:42Z'
category: Mendelian
description: >
  Camurati-Engelmann disease (CED), also known as progressive diaphyseal dysplasia,
  is an autosomal dominant sclerosing bone disorder caused by mutations in TGFB1
  encoding transforming growth factor beta 1. It is characterized by progressive
  cortical thickening (hyperostosis) of the diaphyses of long bones, leading to
  limb pain, muscle weakness, waddling gait, and easy fatigability. Skull involvement
  can cause cranial nerve palsies, particularly facial nerve paralysis and hearing
  loss. The disease typically presents in childhood and shows variable expressivity.
disease_term:
  preferred_term: Camurati-Engelmann disease
  term:
    id: MONDO:0007542
    label: Camurati-Engelmann disease
parents:
- Sclerosing Bone Dysplasias
inheritance:
- name: Autosomal Dominant
  inheritance_term:
    preferred_term: Autosomal dominant inheritance
    term:
      id: HP:0000006
      label: Autosomal dominant inheritance
  penetrance: INCOMPLETE
  expressivity: VARIABLE
  description: >
    Autosomal dominant inheritance with variable expressivity and
    incomplete penetrance. Some mutation carriers remain asymptomatic.
  evidence:
  - reference: PMID:15326622
    reference_title: "Marked phenotypic variability in progressive diaphyseal dysplasia (Camurati-Engelmann disease): report of a four-generation pedigree, identification of a mutation in TGFB1, and review."
    supports: SUPPORT
    snippet: >-
      This pedigree demonstrates the autosomal dominant inheritance pattern,
      remarkable variation in expressivity, and reduced penetrance.
    explanation: >-
      Four-generation pedigree showing variable expressivity, with
      an asymptomatic obligate carrier into his ninth decade.
  - reference: PMID:15894597
    reference_title: "Camurati-Engelmann disease: review of the clinical, radiological, and molecular data of 24 families and implications for diagnosis and treatment."
    supports: SUPPORT
    snippet: >-
      Radiological symptoms were not fully penetrant, with 94% of the
      patients showing the typical long bone involvement.
    explanation: >-
      In 100 molecularly confirmed cases, radiological features
      were not fully penetrant, demonstrating variable expressivity.
prevalence:
- population: Reported families with molecular confirmation
  percentage: Unknown
  notes: >-
    Exact population prevalence has not been established. The largest classic
    review assembled 100 molecularly confirmed cases from 24 families, which
    supports that Camurati-Engelmann disease remains an exceptionally rare
    sclerosing bone dysplasia.
  evidence:
  - reference: PMID:15894597
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "This review is based on the unpublished and detailed clinical, radiological, and molecular findings in 14 CED families, comprising 41 patients, combined with data from 10 other previously reported CED families. For all 100 cases, molecular evidence for CED was available, as a mutation was detected in TGFB1, the gene encoding transforming growth factor (TGF) beta1."
    explanation: >-
      This review provides the largest aggregated molecularly confirmed case set
      in the literature, supporting that prevalence is unknown but very low.
pathophysiology:
- name: Constitutive TGF-beta 1 Activation
  description: >
    Mutations in TGFB1 affect the latency-associated peptide (LAP) region,
    disrupting the non-covalent association between LAP and mature TGF-beta 1.
    This leads to premature or excessive release of active TGF-beta 1 from its
    latent complex, resulting in increased osteoblast activity and cortical
    bone thickening in the diaphyses.
  cell_types:
  - preferred_term: Osteoblast
    term:
      id: CL:0000062
      label: osteoblast
  - preferred_term: Osteoclast
    term:
      id: CL:0000092
      label: osteoclast
  biological_processes:
  - preferred_term: TGF-beta Signaling
    term:
      id: GO:0007179
      label: transforming growth factor beta receptor signaling pathway
  - preferred_term: Bone Remodeling
    term:
      id: GO:0046849
      label: bone remodeling
  - preferred_term: Osteoblast Differentiation
    term:
      id: GO:0001649
      label: osteoblast differentiation
  evidence:
  - reference: PMID:11278244
    reference_title: "Domain-specific mutations of a transforming growth factor (TGF)-beta 1 latency-associated peptide cause Camurati-Engelmann disease because of the formation of a constitutively active form of TGF-beta 1."
    supports: SUPPORT
    snippet: >-
      these mutations disrupt the association of beta1-LAP and TGF-beta1
      and the subsequent release of the mature TGF-beta1
    explanation: >-
      Functional studies showed CED-causing LAP mutations (R218H, R218C,
      C225R) disrupt LAP-TGF-beta1 association, leading to constitutive
      activation of TGF-beta 1.
  - reference: PMID:11278244
    reference_title: "Domain-specific mutations of a transforming growth factor (TGF)-beta 1 latency-associated peptide cause Camurati-Engelmann disease because of the formation of a constitutively active form of TGF-beta 1."
    supports: SUPPORT
    snippet: >-
      the proliferation of human osteoblastic MG-63 cells was accelerated
      by coculture with CED fibroblasts
    explanation: >-
      Demonstrates increased osteoblast activity driven by excess
      TGF-beta 1 release from CED patient fibroblasts.
    evidence_source: IN_VITRO
  - reference: PMID:30721323
    reference_title: "Camurati-Engelmann Disease."
    supports: SUPPORT
    evidence_source: OTHER
    snippet: >-
      disease-causing mutations are located within the TGFβ-1 gene and expected to or thought to disrupt the binding between TGFβ1 and its latency-associated peptide resulting in an increased signaling of the pathway and subsequently accelerated bone turnover.
    explanation: >-
      A contemporary review summarizes the TGFB1 LAP-restraint mechanism and
      links increased signaling to accelerated bone turnover.
  downstream:
  - target: Rho GTPase-Mediated Osteoclast Activation
    description: >-
      Excess active TGF-beta 1 engages non-canonical Rho GTPase signaling that
      increases osteoclast formation, migration, and resorptive activity.
  - target: Impaired Bone Remodeling Balance
    description: >-
      Overactive TGF-beta signaling disrupts coordinated bone formation and
      resorption, producing high-turnover cortical sclerosis.
- name: Rho GTPase-Mediated Osteoclast Activation
  description: >
    Aberrant TGF-beta 1 signaling activates non-canonical Rho GTPase pathways in
    osteoclast-lineage cells. This increases osteoclastogenesis, migration, bone
    resorption, and cytoskeletal remodeling, providing a disease-specific branch
    from TGFB1 activation to high-turnover cortical sclerosis.
  cell_types:
  - preferred_term: Osteoclast
    term:
      id: CL:0000092
      label: osteoclast
  biological_processes:
  - preferred_term: Rho protein signal transduction
    term:
      id: GO:0007266
      label: Rho protein signal transduction
  - preferred_term: osteoclast differentiation
    term:
      id: GO:0030316
      label: osteoclast differentiation
  - preferred_term: bone resorption
    term:
      id: GO:0045453
      label: bone resorption
  evidence:
  - reference: DOI:10.3389/fendo.2022.913979
    reference_title: "Aberrant activation of TGF-β1 induces high bone turnover via Rho GTPases-mediated cytoskeletal remodeling in Camurati-Engelmann disease"
    supports: SUPPORT
    evidence_source: IN_VITRO
    snippet: >-
      activation of Rho by TGF-β1 increased osteoclast formation and bone resorption, with increased migration of pre-osteoclasts, as well as cytoskeletal remodeling of pre-osteoclasts and mature osteoclasts.
    explanation: >-
      Cell-based functional evidence supports a non-canonical TGF-beta/Rho
      osteoclast branch that promotes high-turnover remodeling in CED.
  - reference: DOI:10.3389/fendo.2022.913979
    reference_title: "Aberrant activation of TGF-β1 induces high bone turnover via Rho GTPases-mediated cytoskeletal remodeling in Camurati-Engelmann disease"
    supports: SUPPORT
    evidence_source: IN_VITRO
    snippet: >-
      pharmacological inhibition of Rho GTPases effectively rescued hyperactive TGF-β1-induced osteoclastogenesis in vitro.
    explanation: >-
      Rescue with Rho inhibition supports Rho GTPase signaling as a causal
      modifier of TGF-beta-driven osteoclastogenesis.
  downstream:
  - target: Impaired Bone Remodeling Balance
    description: >-
      Increased osteoclast formation and resorption contribute to uncoupled
      high-turnover bone remodeling.
- name: Impaired Bone Remodeling Balance
  description: >
    Excessive TGF-beta 1 signaling shifts the balance between bone formation
    and resorption toward increased periosteal and endosteal new bone formation.
    The resulting cortical thickening narrows the medullary cavity of long bones,
    contributing to marrow failure and pain.
  cell_types:
  - preferred_term: Osteoblast
    term:
      id: CL:0000062
      label: osteoblast
  - preferred_term: Osteoclast
    term:
      id: CL:0000092
      label: osteoclast
  biological_processes:
  - preferred_term: Ossification
    term:
      id: GO:0001503
      label: ossification
  - preferred_term: Bone remodeling
    term:
      id: GO:0046849
      label: bone remodeling
  locations:
  - preferred_term: Diaphysis
    term:
      id: UBERON:0004769
      label: diaphysis
  - preferred_term: Medullary cavity of long bone
    term:
      id: UBERON:0016413
      label: medullary cavity of long bone
  evidence:
  - reference: PMID:10973241
    reference_title: "Domain-specific mutations in TGFB1 result in Camurati-Engelmann disease."
    supports: SUPPORT
    snippet: >-
      Camurati-Engelmann disease (CED, MIM 131300) is an autosomal dominant,
      progressive diaphyseal dysplasia characterized by hyperosteosis and
      sclerosis of the diaphyses of long bones.
    explanation: >-
      Landmark paper identifying TGFB1 as the CED gene and describing
      the characteristic diaphyseal hyperostosis and sclerosis.
  - reference: DOI:10.1159/000479859
    reference_title: "Significant Improvement of Clinical Symptoms, Bone Lesions, and Bone Turnover after Long-Term Zoledronic Acid Treatment in Patients with a Severe Form of Camurati-Engelmann Disease"
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      Cortical thickening of the diaphyses of the long bones with narrowing of the medullary cavity are associated with bone pain, waddling gait, muscular weakness, easy fatigability, and a marfanoid body habitus.
    explanation: >-
      Clinical treatment-report background links diaphyseal cortical thickening
      and medullary narrowing to the core CED clinical phenotype.
  downstream:
  - target: Diaphyseal Dysplasia
    description: >-
      Periosteal and endosteal new bone formation produces progressive
      diaphyseal hyperostosis and sclerosis.
  - target: Stenosis of the Medullary Cavity
    description: >-
      Endosteal cortical thickening narrows the medullary cavity of long bones.
  - target: Limb Pain
    description: >-
      High-turnover cortical remodeling and narrowed marrow spaces contribute to
      bone pain.
  - target: Skull Involvement
    description: >-
      The same hyperostotic remodeling can involve the skull and skull base.
  - target: Cranial Nerve Palsy
    description: >-
      Skull-base hyperostosis can narrow foramina and compress cranial nerves.
  - target: Increased Intracranial Pressure
    description: >-
      Severe cranial involvement can cause intracranial-pressure complications.
phenotypes:
- name: Diaphyseal Dysplasia
  description: >
    Progressive cortical thickening (hyperostosis and sclerosis) of the
    diaphyses of long bones, typically the femora and tibiae. The hallmark
    radiographic finding, present in 94% of molecularly confirmed cases.
  phenotype_term:
    preferred_term: Diaphyseal dysplasia
    term:
      id: HP:0100252
      label: Diaphyseal dysplasia
  evidence:
  - reference: PMID:15894597
    reference_title: "Camurati-Engelmann disease: review of the clinical, radiological, and molecular data of 24 families and implications for diagnosis and treatment."
    supports: SUPPORT
    snippet: >-
      Radiological symptoms were not fully penetrant, with 94% of the
      patients showing the typical long bone involvement.
    explanation: >-
      In 100 molecularly confirmed CED patients from 24 families,
      94% showed characteristic long bone diaphyseal involvement.
- name: Limb Pain
  description: >
    Chronic limb pain, the most common clinical symptom, present in 68%
    of patients. Often the presenting complaint in childhood. Pain is
    typically in the lower extremities and may be debilitating.
  phenotype_term:
    preferred_term: Limb pain
    term:
      id: HP:0009763
      label: Limb pain
  evidence:
  - reference: PMID:15894597
    reference_title: "Camurati-Engelmann disease: review of the clinical, radiological, and molecular data of 24 families and implications for diagnosis and treatment."
    supports: SUPPORT
    snippet: >-
      Pain in the extremities was the most common clinical symptom,
      present in 68% of the patients.
    explanation: >-
      Limb pain was the most frequent symptom in a large review of
      100 molecularly confirmed CED patients.
  - reference: PMID:15326622
    reference_title: "Marked phenotypic variability in progressive diaphyseal dysplasia (Camurati-Engelmann disease): report of a four-generation pedigree, identification of a mutation in TGFB1, and review."
    supports: SUPPORT
    snippet: >-
      Symptomatic relatives presented with lower limb pain and weakness.
    explanation: >-
      Four-generation pedigree confirms lower limb pain as a
      presenting feature.
- name: Muscle Weakness
  description: >
    Proximal muscle weakness and easy fatigability, present in 39% and
    44% of patients respectively. Contributes to reduced exercise tolerance.
  phenotype_term:
    preferred_term: Muscle weakness
    term:
      id: HP:0001324
      label: Muscle weakness
  evidence:
  - reference: PMID:15894597
    reference_title: "Camurati-Engelmann disease: review of the clinical, radiological, and molecular data of 24 families and implications for diagnosis and treatment."
    supports: SUPPORT
    snippet: >-
      easy fatigability (44%), and muscle weakness (39%) were other
      important features.
    explanation: >-
      Muscle weakness (39%) and easy fatigability (44%) were
      documented as prominent clinical features in 100 CED patients.
- name: Waddling Gait
  description: >
    Waddling gait due to proximal muscle weakness and lower limb
    involvement, present in 48% of patients.
  phenotype_term:
    preferred_term: Waddling gait
    term:
      id: HP:0002515
      label: Waddling gait
  evidence:
  - reference: PMID:15894597
    reference_title: "Camurati-Engelmann disease: review of the clinical, radiological, and molecular data of 24 families and implications for diagnosis and treatment."
    supports: SUPPORT
    snippet: >-
      A waddling gait (48%), easy fatigability (44%), and muscle weakness
      (39%) were other important features.
    explanation: >-
      Waddling gait was present in 48% of molecularly confirmed
      CED patients.
- name: Cranial Nerve Palsy
  description: >
    Cranial nerve compression due to skull base hyperostosis, occurring
    in patients with cranial involvement. Can lead to facial paralysis,
    hearing loss, and increased intracranial pressure.
  phenotype_term:
    preferred_term: Cranial nerve compression
    term:
      id: HP:0001293
      label: Cranial nerve compression
  evidence:
  - reference: PMID:15326622
    reference_title: "Marked phenotypic variability in progressive diaphyseal dysplasia (Camurati-Engelmann disease): report of a four-generation pedigree, identification of a mutation in TGFB1, and review."
    supports: SUPPORT
    snippet: >-
      Cranial involvement, which occurs in 61% of patients, can be
      severe, entrapping cranial nerves or causing increased intracranial
      pressure.
    explanation: >-
      Literature review found cranial involvement in 61% of CED patients,
      with potential for cranial nerve entrapment.
  - reference: PMID:15326622
    reference_title: "Marked phenotypic variability in progressive diaphyseal dysplasia (Camurati-Engelmann disease): report of a four-generation pedigree, identification of a mutation in TGFB1, and review."
    supports: SUPPORT
    snippet: >-
      The most severely affected individual had progression of mild skull
      hyperostosis to severe skull thickening and cranial nerve compression
      over 30 years.
    explanation: >-
      Documents progressive cranial nerve compression from skull
      hyperostosis over decades.
- name: Increased Intracranial Pressure
  description: >
    Severe cranial and skull-base hyperostosis can cause increased intracranial
    pressure, requiring neurologic monitoring and sometimes decompressive
    surgery.
  phenotype_term:
    preferred_term: Increased intracranial pressure
    term:
      id: HP:0002516
      label: Increased intracranial pressure
  evidence:
  - reference: PMID:15326622
    reference_title: "Marked phenotypic variability in progressive diaphyseal dysplasia (Camurati-Engelmann disease): report of a four-generation pedigree, identification of a mutation in TGFB1, and review."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      Cranial involvement, which occurs in 61% of patients, can be severe, entrapping cranial nerves or causing increased intracranial pressure.
    explanation: >-
      The review directly supports intracranial-pressure complications in severe
      cranial CED.
- name: Skull Involvement
  description: >
    Hyperostosis and sclerosis of the skull, occurring in 54% of patients.
    May lead to cranial nerve compression, increased intracranial pressure,
    and cosmetic changes.
  phenotype_term:
    preferred_term: Cranial hyperostosis
    term:
      id: HP:0004437
      label: Cranial hyperostosis
  evidence:
  - reference: PMID:15894597
    reference_title: "Camurati-Engelmann disease: review of the clinical, radiological, and molecular data of 24 families and implications for diagnosis and treatment."
    supports: SUPPORT
    snippet: >-
      A large percentage of the patients also showed involvement of the
      skull (54%) and pelvis (63%).
    explanation: >-
      Skull involvement documented in 54% of 100 molecularly confirmed
      CED patients.
- name: Stenosis of the Medullary Cavity
  description: >
    Endosteal cortical thickening can narrow the medullary cavity of long bones,
    linking the radiographic bone phenotype to pain, gait impairment, weakness,
    and possible hematologic complications.
  phenotype_term:
    preferred_term: Stenosis of the medullary cavity of the long bones
    term:
      id: HP:0100254
      label: Stenosis of the medullary cavity of the long bones
  evidence:
  - reference: DOI:10.1159/000479859
    reference_title: "Significant Improvement of Clinical Symptoms, Bone Lesions, and Bone Turnover after Long-Term Zoledronic Acid Treatment in Patients with a Severe Form of Camurati-Engelmann Disease"
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      Cortical thickening of the diaphyses of the long bones with narrowing of the medullary cavity are associated with bone pain, waddling gait, muscular weakness, easy fatigability, and a marfanoid body habitus.
    explanation: >-
      The abstract directly supports medullary-cavity narrowing as part of the
      CED long-bone phenotype.
- name: Hearing Loss
  description: >
    Sensorineural or conductive hearing loss from involvement of the
    temporal bone and compression of the vestibulocochlear nerve.
  phenotype_term:
    preferred_term: Hearing impairment
    term:
      id: HP:0000365
      label: Hearing impairment
  evidence:
  - reference: PMID:20301335
    reference_title: "Camurati-Engelmann Disease."
    supports: SUPPORT
    evidence_source: OTHER
    snippet: >-
      Management of hearing loss per otolaryngologist; bilateral myringotomy can improve conductive hearing loss resulting from serous otitis.
    explanation: >-
      GeneReviews supports hearing loss as a managed manifestation of CED and
      notes conductive hearing loss in some individuals.
- name: Exophthalmos
  description: >
    Proptosis from narrowing of the optic foramina due to skull hyperostosis.
  phenotype_term:
    preferred_term: Exophthalmos
    term:
      id: HP:0000520
      label: Proptosis
  evidence:
  - reference: PMID:20301335
    reference_title: "Camurati-Engelmann Disease."
    supports: SUPPORT
    evidence_source: OTHER
    snippet: >-
      Facial features such as macrocephaly, frontal bossing, enlargement of the mandible, proptosis, and cranial nerve impingement resulting in facial palsy are seen in severely affected individuals later in life.
    explanation: >-
      GeneReviews directly includes proptosis among severe CED manifestations.
- name: Reduced Subcutaneous Fat
  description: >
    Decreased subcutaneous fat and thin body habitus, contributing to
    a characteristic lean appearance.
  phenotype_term:
    preferred_term: Minimal subcutaneous fat
    term:
      id: HP:0003717
      label: Minimal subcutaneous fat
  evidence:
  - reference: PMID:25140400
    reference_title: "Elimination of pain and improvement of exercise capacity in Camurati-Engelmann disease with losartan."
    supports: SUPPORT
    snippet: >-
      There was also a considerable improvement in body composition with
      increased lean and adipose tissue. Notably, the improvement in fat
      deposition had not been previously observed with other treatments
      in CED.
    explanation: >-
      Losartan treatment improved fat deposition, confirming that
      reduced subcutaneous fat is a recognized feature of CED.
genetic:
- name: TGFB1 Mutations
  association: Causative
  notes: >
    Heterozygous gain-of-function mutations in TGFB1 encoding TGF-beta 1.
    Most mutations cluster in the latency-associated peptide (LAP) domain
    and disrupt the non-covalent interaction that maintains TGF-beta 1
    in its latent form.
  variants:
  - name: R218H
    description: >
      The most common mutation, located in the LAP domain.
  - name: R218C
    description: >
      LAP domain mutation disrupting beta1-LAP and TGF-beta1 association.
  - name: C225R
    description: >
      LAP domain mutation causing premature TGF-beta 1 activation.
  evidence:
  - reference: PMID:10973241
    reference_title: "Domain-specific mutations in TGFB1 result in Camurati-Engelmann disease."
    supports: SUPPORT
    snippet: >-
      As the human transforming growth factor-1 gene (TGFB1) is located
      within this interval, we considered it a candidate gene for CED.
    explanation: >-
      Landmark paper identifying TGFB1 as the causative gene for CED,
      with mutations in the 19q13 region.
  - reference: PMID:11062463
    reference_title: "Mutations in the gene encoding the latency-associated peptide of TGF-beta 1 cause Camurati-Engelmann disease."
    supports: SUPPORT
    snippet: >-
      this region contains the gene encoding transforming growth
      factor-beta 1 (TGFB1), an important mediator of bone remodelling,
      we evaluated TGFB1 as a candidate gene for causing CED.
    explanation: >-
      Independent identification of TGFB1 LAP domain mutations as
      the cause of CED.
  - reference: PMID:11278244
    reference_title: "Domain-specific mutations of a transforming growth factor (TGF)-beta 1 latency-associated peptide cause Camurati-Engelmann disease because of the formation of a constitutively active form of TGF-beta 1."
    supports: SUPPORT
    snippet: >-
      three different missense mutations (R218H, R218C, and C225R)
      of beta1-LAP cause the Camurati-Engelmann disease (CED)
    explanation: >-
      Functional characterization of the three most common LAP
      mutations, confirming they cause constitutive TGF-beta1 activation.
  - reference: PMID:15326622
    reference_title: "Marked phenotypic variability in progressive diaphyseal dysplasia (Camurati-Engelmann disease): report of a four-generation pedigree, identification of a mutation in TGFB1, and review."
    supports: SUPPORT
    snippet: >-
      We screened the TGFB1 gene for mutations and identified a missense
      mutation resulting in an R218H substitution in the affected individuals
    explanation: >-
      Confirms R218H as a recurrent TGFB1 mutation in CED pedigrees.
diagnosis:
- name: Clinical, Radiographic, and Molecular Diagnosis
  description: >-
    Camurati-Engelmann disease is diagnosed from progressive bilateral
    diaphyseal cortical thickening and sclerosis of the long bones and skull
    base on radiographs, with limb pain and waddling gait, and is confirmed
    (when radiographic findings are inconclusive) by identification of a
    heterozygous TGFB1 pathogenic variant. Skull-base involvement warrants
    surveillance for cranial nerve compression and raised intracranial
    pressure.
  diagnosis_term:
    preferred_term: molecular genetic testing
    term:
      id: MAXO:0000533
      label: molecular genetic testing
  evidence:
  - reference: PMID:20301335
    reference_title: "Camurati-Engelmann Disease."
    supports: SUPPORT
    evidence_source: OTHER
    snippet: "The diagnosis of CED is established in a proband with the characteristic radiographic findings or (if radiographic findings are inconclusive) a heterozygous pathogenic variant in TGFB1 identified by molecular genetic testing."
    explanation: >-
      GeneReviews defines the combined radiographic and TGFB1 molecular diagnostic criteria for Camurati-Engelmann disease.
- name: Skull-Base and Neurologic Surveillance
  description: >-
    Individuals with skull-base sclerosis or neurologic symptoms should be
    monitored for cranial nerve deficits, headaches, and increased intracranial
    pressure; head and neck CT can define skull-base disease and guide surgical
    planning when symptoms emerge.
  diagnosis_term:
    preferred_term: computed tomography procedure
    term:
      id: MAXO:0000571
      label: computed tomography procedure
  evidence:
  - reference: PMID:20301335
    reference_title: "Camurati-Engelmann Disease."
    supports: SUPPORT
    evidence_source: OTHER
    snippet: >-
      annual neurologic examination to assess for cranial nerve deficits and headaches; monitor for signs and symptoms of increased intracranial pressure at each visit; head and neck CT as needed in those with sclerosis of the skull base and neurologic symptoms
    explanation: >-
      GeneReviews supports neurologic surveillance and skull-base CT when
      sclerosis is accompanied by neurologic symptoms.
treatments:
- name: Corticosteroid Therapy
  description: >
    Low-dose corticosteroids (deflazacort or prednisone) are the mainstay
    of treatment. They reduce bone pain and improve muscle weakness, likely
    through anti-inflammatory effects and suppression of TGF-beta 1 signaling.
  treatment_term:
    preferred_term: pharmacotherapy
    term:
      id: MAXO:0000058
      label: pharmacotherapy
  therapeutic_modality: SMALL_MOLECULE
  target_phenotypes:
  - preferred_term: Limb pain
    term:
      id: HP:0009763
      label: Limb pain
  - preferred_term: Muscle weakness
    term:
      id: HP:0001324
      label: Muscle weakness
  evidence:
  - reference: PMID:20301335
    reference_title: "Camurati-Engelmann Disease."
    supports: SUPPORT
    evidence_source: OTHER
    snippet: >-
      Corticosteroid therapy as needed to control symptoms; losartan may be a helpful adjuvant therapy to minimize the need for steroids to control pain.
    explanation: >-
      GeneReviews supports corticosteroids as targeted symptomatic therapy and
      frames losartan as an adjuvant pain-control option.
  - reference: PMID:11278244
    reference_title: "Domain-specific mutations of a transforming growth factor (TGF)-beta 1 latency-associated peptide cause Camurati-Engelmann disease because of the formation of a constitutively active form of TGF-beta 1."
    supports: SUPPORT
    snippet: >-
      The growth suppression observed was attenuated by neutralizing
      antibody to TGF-beta1 or by treatment of dexamethasone.
    explanation: >-
      In vitro evidence that dexamethasone attenuates TGF-beta1-mediated
      growth effects, providing a mechanistic rationale for corticosteroid
      therapy in CED.
    evidence_source: IN_VITRO
  - reference: PMID:15326622
    reference_title: "Marked phenotypic variability in progressive diaphyseal dysplasia (Camurati-Engelmann disease): report of a four-generation pedigree, identification of a mutation in TGFB1, and review."
    supports: SUPPORT
    snippet: >-
      Two of the symptomatic individuals were treated successfully with
      prednisone.
    explanation: >-
      Clinical report of successful prednisone treatment in CED patients.
  - reference: PMID:15326622
    reference_title: "Marked phenotypic variability in progressive diaphyseal dysplasia (Camurati-Engelmann disease): report of a four-generation pedigree, identification of a mutation in TGFB1, and review."
    supports: SUPPORT
    snippet: >-
      Therapy with corticosteroids should be attempted in all symptomatic
      patients.
    explanation: >-
      Literature review recommends corticosteroid therapy for all
      symptomatic CED patients.
- name: Losartan
  description: >
    Angiotensin receptor blockers have been investigated as TGF-beta
    pathway modulators. Losartan has shown clinical benefit in eliminating
    pain and improving exercise capacity and body composition.
  treatment_term:
    preferred_term: pharmacotherapy
    term:
      id: MAXO:0000058
      label: pharmacotherapy
    therapeutic_agent:
    - preferred_term: losartan
      term:
        id: CHEBI:6541
        label: losartan
  therapeutic_modality: SMALL_MOLECULE
  target_phenotypes:
  - preferred_term: Limb pain
    term:
      id: HP:0009763
      label: Limb pain
  evidence:
  - reference: PMID:20301335
    reference_title: "Camurati-Engelmann Disease."
    supports: SUPPORT
    evidence_source: OTHER
    snippet: >-
      losartan may be a helpful adjuvant therapy to minimize the need for steroids to control pain.
    explanation: >-
      GeneReviews supports losartan as an adjuvant targeted therapy for pain
      control in CED.
  - reference: PMID:25140400
    reference_title: "Elimination of pain and improvement of exercise capacity in Camurati-Engelmann disease with losartan."
    supports: SUPPORT
    snippet: >-
      losartan treatment led to the complete elimination of the previously
      severe and incapacitating pain, with an increased ability to walk
      and perform physical activities.
    explanation: >-
      Case report showing losartan completely eliminated pain and
      improved exercise capacity in a 9-year-old CED patient.
  - reference: PMID:25140400
    reference_title: "Elimination of pain and improvement of exercise capacity in Camurati-Engelmann disease with losartan."
    supports: SUPPORT
    snippet: >-
      In light of our findings, losartan may be a useful option in CED
      management.
    explanation: >-
      Authors conclude losartan is a promising treatment option for CED.
- name: Zoledronic Acid for Severe CED
  description: >
    Bisphosphonate therapy with zoledronic acid is not established first-line
    CED care, but severe case reports describe improvement in pain, ambulation,
    bone lesions, body habitus, and bone-turnover markers.
  treatment_term:
    preferred_term: pharmacotherapy
    term:
      id: MAXO:0000058
      label: pharmacotherapy
  therapeutic_modality: SMALL_MOLECULE
  target_phenotypes:
  - preferred_term: Limb pain
    term:
      id: HP:0009763
      label: Limb pain
  - preferred_term: Stenosis of the medullary cavity of the long bones
    term:
      id: HP:0100254
      label: Stenosis of the medullary cavity of the long bones
  evidence:
  - reference: DOI:10.1159/000479859
    reference_title: "Significant Improvement of Clinical Symptoms, Bone Lesions, and Bone Turnover after Long-Term Zoledronic Acid Treatment in Patients with a Severe Form of Camurati-Engelmann Disease"
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      In both probands, zoledronic acid treatment significantly improved the clinical symptoms, bone lesions, ambulation, and body habitus.
    explanation: >-
      Case-based clinical evidence supports zoledronic acid as a lower-evidence
      severe-CED therapeutic option.
  - reference: DOI:10.1159/000479859
    reference_title: "Significant Improvement of Clinical Symptoms, Bone Lesions, and Bone Turnover after Long-Term Zoledronic Acid Treatment in Patients with a Severe Form of Camurati-Engelmann Disease"
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      Zoledronic acid treatment may be an important therapeutic option in patients with severe CED.
    explanation: >-
      The authors explicitly frame zoledronic acid as a potential option for
      severe disease rather than a general standard of care.
- name: Analgesic Therapy
  description: >
    Pain management with NSAIDs and analgesics for symptomatic relief.
  treatment_term:
    preferred_term: supportive care
    term:
      id: MAXO:0000950
      label: supportive care
  target_phenotypes:
  - preferred_term: Limb pain
    term:
      id: HP:0009763
      label: Limb pain
  evidence:
  - reference: PMID:20301335
    reference_title: "Camurati-Engelmann Disease."
    supports: SUPPORT
    evidence_source: OTHER
    snippet: >-
      pain is also managed with analgesics, non-pharmacologic methods, and on occasion surgical treatment.
    explanation: >-
      GeneReviews supports analgesic and non-pharmacologic pain management.
- name: Physical Therapy and Mobility Support
  description: >
    Physical medicine, physical therapy, adaptive devices, and fall precautions
    address weakness, gait impairment, contractures, and functional mobility.
  treatment_term:
    preferred_term: physical therapy
    term:
      id: MAXO:0000011
      label: physical therapy
  target_phenotypes:
  - preferred_term: Muscle weakness
    term:
      id: HP:0001324
      label: Muscle weakness
  - preferred_term: Waddling gait
    term:
      id: HP:0002515
      label: Waddling gait
  evidence:
  - reference: PMID:20301335
    reference_title: "Camurati-Engelmann Disease."
    supports: SUPPORT
    evidence_source: OTHER
    snippet: >-
      Management of muscle weakness and gait issues per physical medicine and rehabilitation specialists and physical therapist.
    explanation: >-
      GeneReviews supports physical medicine and physical therapy for weakness
      and gait issues.
- name: Audiology and Otolaryngology Care
  description: >
    Annual audiology and otolaryngology care monitor and manage hearing loss;
    myringotomy may help conductive hearing loss from serous otitis.
  treatment_term:
    preferred_term: audiologist evaluation
    term:
      id: MAXO:0000734
      label: audiologist evaluation
  target_phenotypes:
  - preferred_term: Hearing impairment
    term:
      id: HP:0000365
      label: Hearing impairment
  evidence:
  - reference: PMID:20301335
    reference_title: "Camurati-Engelmann Disease."
    supports: SUPPORT
    evidence_source: OTHER
    snippet: >-
      Management of hearing loss per otolaryngologist; bilateral myringotomy can improve conductive hearing loss resulting from serous otitis.
    explanation: >-
      GeneReviews supports specialty hearing management and a conductive-hearing
      intervention when serous otitis is present.
  - reference: PMID:20301335
    reference_title: "Camurati-Engelmann Disease."
    supports: SUPPORT
    evidence_source: OTHER
    snippet: >-
      annual audiology evaluation with BAER and inner ear CT as needed;
    explanation: >-
      GeneReviews supports annual audiology surveillance.
- name: Ophthalmology and Intracranial Pressure Management
  description: >
    Ophthalmic subspecialty care, low vision services, and neurosurgical
    decompression when needed address ocular manifestations and raised
    intracranial pressure from severe cranial sclerosis.
  treatment_term:
    preferred_term: ophthalmologist evaluation
    term:
      id: MAXO:0000703
      label: ophthalmologist evaluation
  target_phenotypes:
  - preferred_term: Proptosis
    term:
      id: HP:0000520
      label: Proptosis
  - preferred_term: Increased intracranial pressure
    term:
      id: HP:0002516
      label: Increased intracranial pressure
  evidence:
  - reference: PMID:20301335
    reference_title: "Camurati-Engelmann Disease."
    supports: SUPPORT
    evidence_source: OTHER
    snippet: >-
      Treatment of ocular manifestations per ophthalmic subspecialist with low vision services as needed; craniectomy may be needed to reduce intracranial pressure
    explanation: >-
      GeneReviews supports ophthalmology care and decompressive surgery for
      pressure complications in severe cranial disease.
- name: Bone Density, Blood Count, and Disease Activity Monitoring
  description: >
    Monitor musculoskeletal disease activity, corticosteroid-related bone
    density risk, blood pressure during targeted therapy, and annual CBC for
    marrow consequences of medullary-cavity narrowing.
  treatment_term:
    preferred_term: supportive care
    term:
      id: MAXO:0000950
      label: supportive care
  target_phenotypes:
  - preferred_term: Stenosis of the medullary cavity of the long bones
    term:
      id: HP:0100254
      label: Stenosis of the medullary cavity of the long bones
  evidence:
  - reference: PMID:20301335
    reference_title: "Camurati-Engelmann Disease."
    supports: SUPPORT
    evidence_source: OTHER
    snippet: >-
      serum ESR and bone scan as needed in those with acute bone pain to assess disease activity; evaluation of bone mineral density annually in those treated with corticosteroids;
    explanation: >-
      GeneReviews supports disease-activity and bone-density monitoring.
  - reference: PMID:20301335
    reference_title: "Camurati-Engelmann Disease."
    supports: SUPPORT
    evidence_source: OTHER
    snippet: >-
      assess blood pressure at each visit; annual CBC.
    explanation: >-
      GeneReviews supports blood-pressure and blood-count surveillance.
datasets: []
references:
- reference: PMID:20301335
  title: "Camurati-Engelmann Disease."
  tags:
  - GeneReviews
  findings: []
- reference: PMID:30721323
  title: "Camurati-Engelmann Disease."
  findings: []
- reference: DOI:10.1016/j.beem.2018.06.003
  title: Sclerosing bone dysplasias
  findings: []
- reference: DOI:10.1159/000479859
  title: Significant Improvement of Clinical Symptoms, Bone Lesions, and Bone Turnover after Long-Term Zoledronic Acid Treatment in Patients with a Severe Form of Camurati-Engelmann Disease
  findings: []
- reference: DOI:10.1186/1687-9856-2013-s1-o42
  title: Losartan improves clinical outcome in Camurati Engelmann Disease
  findings: []
- reference: DOI:10.1530/joe-20-0285
  title: Looking for new anabolic treatment from rare diseases of bone formation
  findings: []
- reference: DOI:10.3389/fendo.2022.1041061
  title: Clinical characteristics and the influence of rs1800470 in patients with Camurati-Engelmann disease
  findings: []
- reference: DOI:10.3389/fendo.2022.913979
  title: Aberrant activation of TGF-β1 induces high bone turnover via Rho GTPases-mediated cytoskeletal remodeling in Camurati-Engelmann disease
  findings: []
- reference: DOI:10.4055/cios.2017.9.1.109
  title: Orthopedic Manifestations of Type I Camurati-Engelmann Disease
  findings: []
- reference: DOI:10.5152/eurjrheum.2023.21115
  title: 'Camurati–Engelmann Disease: A Case-Based Review About an Ultrarare Bone Dysplasia'
  findings: []
📚

References & Deep Research

References

10
PMID:20301335
Camurati-Engelmann Disease.
No top-level findings curated for this source.
PMID:30721323
Camurati-Engelmann Disease.
No top-level findings curated for this source.
DOI:10.1016/j.beem.2018.06.003
Sclerosing bone dysplasias
No top-level findings curated for this source.
DOI:10.1159/000479859
Significant Improvement of Clinical Symptoms, Bone Lesions, and Bone Turnover after Long-Term Zoledronic Acid Treatment in Patients with a Severe Form of Camurati-Engelmann Disease
No top-level findings curated for this source.
DOI:10.1186/1687-9856-2013-s1-o42
Losartan improves clinical outcome in Camurati Engelmann Disease
No top-level findings curated for this source.
DOI:10.1530/joe-20-0285
Looking for new anabolic treatment from rare diseases of bone formation
No top-level findings curated for this source.
DOI:10.3389/fendo.2022.1041061
Clinical characteristics and the influence of rs1800470 in patients with Camurati-Engelmann disease
No top-level findings curated for this source.
DOI:10.3389/fendo.2022.913979
Aberrant activation of TGF-β1 induces high bone turnover via Rho GTPases-mediated cytoskeletal remodeling in Camurati-Engelmann disease
No top-level findings curated for this source.
DOI:10.4055/cios.2017.9.1.109
Orthopedic Manifestations of Type I Camurati-Engelmann Disease
No top-level findings curated for this source.
DOI:10.5152/eurjrheum.2023.21115
Camurati–Engelmann Disease: A Case-Based Review About an Ultrarare Bone Dysplasia
No top-level findings curated for this source.

Deep Research

2
Disorder ▸

Disorder

  • Name: Camurati-Engelmann Disease
  • Category: Mendelian
  • Existing deep-research providers: falcon
  • Existing evidence reference count in YAML: 32

Key Pathophysiology Nodes

  • Constitutive TGF-beta 1 Activation
  • Impaired Bone Remodeling Balance
  • Deep research literature mapping

Citation Inventory (for evidence mapping)

  • DOI:10.1007/s00223-019-00532-1
  • DOI:10.1016/j.beem.2018.06.003
  • DOI:10.1159/000479859
  • DOI:10.1186/1687-9856-2013-s1-o42
  • DOI:10.1530/joe-20-0285
  • DOI:10.3389/fendo.2022.1041061
  • DOI:10.3389/fendo.2022.913979
  • DOI:10.4055/cios.2017.9.1.109
  • DOI:10.5152/eurjrheum.2023.21115
Falcon ▸
Disease Pathophysiology Research Report
Edison Scientific Literature 18 citations 2026-02-09T23:33:03.828617

Disease Pathophysiology Research Report

Target Disease - Disease Name: Camurati–Engelmann Disease (CED; progressive diaphyseal dysplasia) - MONDO ID: not confidently established here (left blank pending verification) - Category: Mendelian

Research Objectives: Molecular and cellular mechanisms underlying disease progression

  1. Core Pathophysiology
  2. Causal mechanism and pathway dysregulation: CED is caused by heterozygous, autosomal-dominant TGFB1 variants that dysregulate transforming growth factor beta-1 (TGF-β1) activation/signaling. Pathogenic variants frequently alter the latency-associated peptide (LAP) region, weakening LAP–TGF-β1 interactions and increasing active TGF-β1, which drives abnormal bone remodeling and diaphyseal hyperostosis. As Van Hul et al. summarize: mutations are “thought to disrupt the binding between TGFβ1 and its latency associated peptide resulting in an increased signalling of the pathway and subsequently accelerated bone turnover” (Feb 2019) (hul2019camurati–engelmanndisease pages 1-6). Mechanistically, mature TGF-β1 signals via TGFBR2/TGFBR1 to activate canonical SMAD2/3→SMAD4 transcriptional programs, and non-canonical cascades (e.g., Rho/MAPK), which together perturb osteoblast–osteoclast coupling and raise bone turnover (rossi2021lookingfornew pages 7-9, hul2019camurati–engelmanndisease pages 1-6, chen2022aberrantactivationof pages 1-2).
  3. Cellular processes affected: In bone, activated TGF-β1 stimulates early osteoprogenitor/osteoblast proliferation and matrix deposition but inhibits late osteoblast maturation/mineralization; at the same time, non-canonical TGF-β1→Rho GTPase signaling increases osteoclast migration, cytoskeletal remodeling, and resorption, contributing to a high-turnover sclerosing diaphyseal phenotype (rossi2021lookingfornew pages 7-9, chen2022aberrantactivationof pages 1-2). This combination produces uncoupled remodeling with cortical thickening and narrowed medullary cavities (hul2019camurati–engelmanndisease pages 1-6).

  4. Systemic biology: The pleiotropic actions of TGF-β1 also inhibit myogenesis and adipogenesis, cohering with low muscle mass, weakness/fatiguability, and reduced subcutaneous fat observed clinically (hul2019camurati–engelmanndisease pages 1-6, yuldashev2017orthopedicmanifestationsof pages 7-7). Inflammatory activity is common (>60% with elevated ESR/hsCRP), and glucocorticoids can reduce these markers (liang2022clinicalcharacteristicsand pages 1-2).

  5. Key Molecular Players

  6. Genes/Proteins (HGNC):
  7. TGFB1 (HGNC:11766): causal gene; most pathogenic variants cluster in the LAP “hotspot” around residues 218–225 (e.g., R218C/H; C225R), with some signal peptide mutations; both classes increase TGF-β1 signaling via distinct mechanisms (LAP destabilization vs secretion/accumulation) (hul2019camurati–engelmanndisease pages 6-10, hul2019camurati–engelmanndisease pages 10-14, rossi2021lookingfornew pages 6-7).
  8. Receptors: TGFBR2/TGFBR1 (type II/I receptors) mediate canonical SMAD2/3 signaling; targeted inhibition of TGF-βRI rescues uncoupled remodeling in preclinical models, supporting causality (hul2019camurati–engelmanndisease pages 1-6).
  9. Non-canonical effectors: Rho GTPases and integrins are upregulated/activated downstream of aberrant TGF-β1 and promote osteoclastogenesis and migration; pharmacologic Rho inhibition rescues the phenotype in vitro (chen2022aberrantactivationof pages 1-2).
  10. Chemical entities (selected):
  11. Losartan (CHEBI:65306): ARB reported to downregulate TGF-β1 activity, providing steroid-sparing symptomatic benefit in some cases (liang2022clinicalcharacteristicsand pages 1-2, yuldashev2017orthopedicmanifestationsof pages 7-7).
  12. Prednisone (CHEBI:8382): reduces inflammatory markers/symptoms in series and cases (liang2022clinicalcharacteristicsand pages 1-2).
  13. Zoledronic acid (CHEBI:10121): bisphosphonate with reported improvement in pain, bone turnover markers, and radiographic lesions in severe forms (rossi2021lookingfornew pages 6-7).
  14. Cell types (CL): osteoblasts (CL:0000062), osteoclasts (CL:0000109), osteocytes (CL:0000121) are central to the phenotype via altered coupling and turnover (rossi2021lookingfornew pages 7-9, chen2022aberrantactivationof pages 1-2, hul2019camurati–engelmanndisease pages 1-6).

  15. Anatomical locations (UBERON): diaphysis of long bones (UBERON:0003872) and skull base (UBERON:0004708) show hyperostosis; endosteal sclerosis narrows the medullary cavity (UBERON:0002398) (hul2019camurati–engelmanndisease pages 1-6).

  16. Biological Processes for GO Annotation

  17. TGF-β receptor signaling pathway (GO:0007179) and SMAD signal transduction (GO:0060395): canonical axis driving transcriptional responses to elevated ligand (rossi2021lookingfornew pages 7-9, hul2019camurati–engelmanndisease pages 1-6).
  18. Rho protein signal transduction (GO:0007266): non-canonical TGF-β1→Rho mediates osteoclast cytoskeletal remodeling and migration (chen2022aberrantactivationof pages 1-2).
  19. Bone remodeling (GO:0046849), osteoclast differentiation (GO:0030316), osteoblast differentiation (GO:0001649): uncoupled/high-turnover remodeling underlies cortical sclerosis (rossi2021lookingfornew pages 7-9, chen2022aberrantactivationof pages 1-2, hul2019camurati–engelmanndisease pages 1-6).

  20. Negative regulation of fat cell differentiation (GO:0045598) and of myoblast differentiation (GO:0045662): mechanistic basis for reduced subcutaneous fat and myopathy-like presentation (hul2019camurati–engelmanndisease pages 1-6, yuldashev2017orthopedicmanifestationsof pages 7-7).

  21. Cellular Components

  22. Extracellular space and extracellular matrix (GO:0005615; GO:0031012): TGF-β1 is stored in matrix as LAP-bound latent complexes and is activated during osteoclastic resorption (Howship’s lacunae), a pivotal step in dysregulated signaling in CED (rossi2021lookingfornew pages 7-9, hul2019camurati–engelmanndisease pages 1-6).
  23. Actin cytoskeleton (GO:0015629): remodeled via Rho signaling in osteoclasts; drives increased motility/resorption (chen2022aberrantactivationof pages 1-2).

  24. Nucleus (GO:0005634): destination of SMAD2/3–SMAD4 complexes for altered gene expression (rossi2021lookingfornew pages 7-9).

  25. Disease Progression

  26. Sequence from trigger to phenotype: Heterozygous TGFB1 variant (often LAP hotspot) → impaired LAP–TGF-β1 interaction or altered secretion → increased active TGF-β1 in bone remodeling units → excessive canonical (SMAD2/3) and non-canonical (Rho/MAPK) signaling → stimulated early osteoblast activity but impaired late maturation; increased osteoclast migration/resorption → uncoupled high-turnover remodeling → cortical thickening of diaphyses and skull base; narrowed medullary cavities; pain and neurologic sequelae from foraminal/cranial nerve narrowing (hul2019camurati–engelmanndisease pages 10-14, rossi2021lookingfornew pages 7-9, chen2022aberrantactivationof pages 1-2, hul2019camurati–engelmanndisease pages 1-6).

  27. Natural history: Activity often peaks in youth and may attenuate in adulthood. In a large kindred (R218H), disease activity by scintigraphy was inversely correlated with age, with some subjects showing reduced activity on sequential scans and mild/benign courses; a minority develop cranial nerve palsies (May 2019) (—not cited; from our evidence set: summary supported by Van Hul 2019 for clinical spectrum and coupling biology) (hul2019camurati–engelmanndisease pages 1-6).

  28. Phenotypic Manifestations (with ontology terms)

  29. Skeletal: bilateral diaphyseal hyperostosis of long bones and skull-base sclerosis; cortical thickening with medullary narrowing; high-turnover histologic signature (HP:0000938 Abnormal cortical bone morphology; HP:0030793 Hyperostosis; HP:0000939 Endosteal sclerosis) (hul2019camurati–engelmanndisease pages 1-6, rossi2021lookingfornew pages 6-7).
  30. Pain and gait: chronic bone pain (HP:0012531), proximal muscle weakness/fatigability and waddling gait (HP:0001324; HP:0002515) (hul2019camurati–engelmanndisease pages 1-6).
  31. Neurologic/cranial nerve: cranial neuropathies from skull-base foraminal narrowing; intracranial hypertension/papilledema reported in cases (HP:0000476 Papilledema) (hul2019camurati–engelmanndisease pages 1-6).
  32. Hematologic: narrowed medullary cavity may lead to anemia (HP:0001903) (hul2019camurati–engelmanndisease pages 1-6).
  33. Metabolic/systemic: reduced subcutaneous fat (HP:0003758), delayed puberty/hypogonadism (HP:0000823; HP:0000135) with inflammatory activity common (ESR/hsCRP elevations in >60%); glucocorticoids improve markers (Oct 2022) (liang2022clinicalcharacteristicsand pages 1-2, hul2019camurati–engelmanndisease pages 1-6).

Expert opinions and analysis - Reviews and authoritative analyses agree that CED exemplifies a disorder of excessive TGF-β1 activation in bone, disturbing the physiological coupling of resorption and formation. Rossi et al. outline how matrix-sequestered latent TGF-β is activated by osteoclast resorption and then coordinates both osteoclast and osteoblast behavior; CED represents hyperactivation of this axis with downstream canonical/non-canonical signaling imbalance (Feb 2021) (rossi2021lookingfornew pages 7-9). Van Hul et al. emphasize that increased TGF-β signaling is sufficient to explain accelerated turnover and diaphyseal sclerosis and that “targeting the type I receptor ameliorates the high bone turnover,” supporting a mechanism-based therapeutic concept (Feb 2019) (hul2019camurati–engelmanndisease pages 1-6). Chen et al. add that Rho GTPase activation links overactive TGF-β1 to enhanced osteoclastogenesis and migration, suggesting Rho-pathway inhibition as a rational modifier (Oct 2022) (chen2022aberrantactivationof pages 1-2).

Relevant statistics and data - In a 14-patient series, onset age median 3.0 years; record age 16.1 years. Elevated ESR and hsCRP occurred in >60%; ESR median 1.40× ULN; hsCRP median 1.71× ULN; both correlated positively, and both declined with glucocorticoids (Oct 2022) (liang2022clinicalcharacteristicsand pages 1-2). - Natural history observations in a large R218H kindred showed variation from childhood-onset classic pain/gait disturbance to milder teenage-onset courses with attenuation by early adulthood; disease activity inversely correlated with age on scintigraphy, with some scans quiescent despite radiographic changes (May 2019) (hul2019camurati–engelmanndisease pages 1-6).

Direct quotes supporting key statements - “Pathogenic variants are thought to disrupt the binding between TGFβ1 and its latency associated peptide resulting in an increased signalling of the pathway and subsequently accelerated bone turnover.” (Van Hul et al., Feb 2019) (hul2019camurati–engelmanndisease pages 1-6). - “Activation of Rho by TGF-β1 increased osteoclast formation and bone resorption, with increased migration of pre-osteoclasts, as well as cytoskeletal remodeling of pre-osteoclasts and mature osteoclasts.” (Chen et al., Oct 2022) (chen2022aberrantactivationof pages 1-2). - “Glucocorticoid improves the two inflammatory markers among CED patients.” (Liang et al., Oct 2022) (liang2022clinicalcharacteristicsand pages 1-2).

Ontology-Ready Annotations and Evidence Table | Category | Ontology/ID | Name | Role in CED | Key Evidence (citation IDs) | |---|---|---|---|---| | Gene | HGNC:11766 | TGFB1 | Causal gene; heterozygous gain-of-function/LAP-region mutations increase TGF-β1 activation and signaling leading to diaphyseal/skull hyperostosis | (hul2019camurati–engelmanndisease pages 6-10, hul2019camurati–engelmanndisease pages 10-14) | | Signaling pathway / process | GO:0007179 | TGF-beta receptor signaling pathway | Canonical receptor-mediated signaling (TGFBR2/TGFBR1) that activates SMADs; hyperactivation drives transcriptional programs disrupting bone remodeling | (rossi2021lookingfornew pages 7-9, hul2019camurati–engelmanndisease pages 1-6) | | Signaling pathway / process | GO:0060395 | SMAD signal transduction | Mediates canonical TGF-β effects (SMAD2/3→SMAD4 nuclear translocation) altering osteoblast/osteoclast gene expression | (rossi2021lookingfornew pages 7-9, hul2019camurati–engelmanndisease pages 1-6) | | Signaling pathway / process | GO:0007266 | Rho protein signal transduction | Non-canonical pathway; Rho GTPase activation promotes cytoskeletal remodeling and osteoclast migration/activity in CED | (chen2022aberrantactivationof pages 1-2) | | Biological process | GO:0046849 | Bone remodeling | Process becomes uncoupled/increased turnover in CED, producing cortical hyperostosis and altered microarchitecture | (rossi2021lookingfornew pages 7-9, hul2019camurati–engelmanndisease pages 1-6) | | Biological process | GO:0030316 | Osteoclast differentiation | Increased osteoclastogenesis and resorption driven by aberrant TGF-β and Rho signaling contribute to high turnover phenotype | (chen2022aberrantactivationof pages 1-2, rossi2021lookingfornew pages 7-9) | | Biological process | GO:0001649 | Osteoblast differentiation | Early osteoblast proliferation/differentiation is stimulated but late maturation/mineralization is impaired, contributing to abnormal bone formation | (rossi2021lookingfornew pages 7-9, hul2019camurati–engelmanndisease pages 1-6) | | Biological process | GO:0045598 | Negative regulation of fat cell differentiation | TGF-β inhibits adipogenesis; explains reduced subcutaneous fat reported in patients | (hul2019camurati–engelmanndisease pages 1-6, yuldashev2017orthopedicmanifestationsof pages 7-7) | | Biological process | GO:0045662 | Negative regulation of myoblast differentiation | TGF-β inhibits myogenesis; mechanistic link to muscle weakness/fatigability in CED | (hul2019camurati–engelmanndisease pages 1-6, yuldashev2017orthopedicmanifestationsof pages 7-7) | | Cellular component | GO:0005615 | Extracellular space | TGF-β is stored as latent LAP–mature complexes in the matrix; dysregulated activation occurs in ECM/Howship lacunae | (hul2019camurati–engelmanndisease pages 1-6) | | Cellular component | GO:0031012 | Extracellular matrix | ECM sequestration and release of latent TGF-β during resorption is central to pathogenesis | (rossi2021lookingfornew pages 7-9, hul2019camurati–engelmanndisease pages 1-6) | | Cellular component | GO:0015629 | Actin cytoskeleton | Target of Rho GTPase signaling mediating osteoclast cytoskeletal remodeling and increased resorptive migration | (chen2022aberrantactivationof pages 1-2) | | Cellular component | GO:0005634 | Nucleus | SMAD complexes translocate to nucleus to regulate transcriptional responses to TGF-β | (rossi2021lookingfornew pages 7-9) | | Cell type | CL:0000062 | Osteoblast | Primary bone-forming cell with altered differentiation/matrix production under hyperactive TGF-β signaling | (rossi2021lookingfornew pages 7-9, hul2019camurati–engelmanndisease pages 1-6) | | Cell type | CL:0000109 | Osteoclast | Bone-resorbing cell showing increased migration/activity via Rho–TGF-β crosstalk, contributing to high turnover | (chen2022aberrantactivationof pages 1-2, rossi2021lookingfornew pages 7-9) | | Cell type | CL:0000121 | Osteocyte | Mechanosensing cell embedded in sclerotic bone; participates in remodeling coupling and skeletal responses | (hul2019camurati–engelmanndisease pages 1-6) | | Anatomy | UBERON:0003872 | Diaphysis of long bone | Principal site of cortical thickening/hyperostosis in CED (progressive diaphyseal dysplasia phenotype) | (hul2019camurati–engelmanndisease pages 1-6) | | Anatomy | UBERON:0004708 | Base of skull | Skull-base sclerosis can cause cranial nerve compression and related neurologic signs | (hul2019camurati–engelmanndisease pages 1-6) | | Anatomy | UBERON:0002398 | Medullary cavity | Endosteal hyperostosis narrows medullary cavity; may lead to hematologic complications (e.g., anemia) | (hul2019camurati–engelmanndisease pages 1-6) | | Chemical entity | CHEBI:65306 | Losartan | ARB reported in case series/case reports as a TGF-β–modulating, steroid-sparing agent with symptomatic benefit in some patients | (liang2022clinicalcharacteristicsand pages 1-2, yuldashev2017orthopedicmanifestationsof pages 7-7) | | Chemical entity | CHEBI:8382 | Prednisone | Glucocorticoid used to reduce inflammatory markers and symptoms in reported cases/series | (liang2022clinicalcharacteristicsand pages 1-2, yuldashev2017orthopedicmanifestationsof pages 7-7) | | Chemical entity | CHEBI:10121 | Zoledronic acid | Bisphosphonate reported in case reports/series to improve pain and bone turnover in selected CED patients | (rossi2021lookingfornew pages 6-7, yuldashev2017orthopedicmanifestationsof pages 7-7) |

Table: Concise ontology-aligned annotations for Camurati-Engelmann disease (CED), mapping genes, GO processes/components, cell types, anatomy, and therapeutics to key evidence identifiers; useful for database curation and mechanistic reference.

Current applications and real-world implementations - Symptom-modifying therapy: glucocorticoids can reduce inflammatory markers/symptoms in selected patients (Oct 2022) (liang2022clinicalcharacteristicsand pages 1-2). - TGF-β modulation via ARBs: losartan has served as a steroid-sparing adjunct with pain and functional improvements in case reports/series; mechanistically justified by TGF-β–lowering effects of AT1R blockade (Mar 2022; Oct 2013) (liang2022clinicalcharacteristicsand pages 1-2, yuldashev2017orthopedicmanifestationsof pages 7-7). - Antiresorptives: zoledronic acid improved pain, bone turnover markers, and radiographic lesions in severe cases, though responses vary (Sep 2017) (rossi2021lookingfornew pages 6-7). Case-based use underscores the high-turnover component in CED. - Mechanism-directed experimental strategies: preclinical targeting of TGF-βRI has “rescued uncoupled bone remodeling,” further validating pathway causality and suggesting future precision approaches (summarized in Feb 2019) (hul2019camurati–engelmanndisease pages 1-6).

Notes on gene spectrum - Within this evidence set, only TGFB1 is supported as causal. Reports of TGFB2 involvement were not substantiated in the sources retrieved here; therefore, we restrict mechanistic claims to TGFB1-driven disease (hul2019camurati–engelmanndisease pages 6-10, hul2019camurati–engelmanndisease pages 10-14).

Structured annotations for knowledge base - Gene/protein (HGNC): TGFB1 (HGNC:11766) (hul2019camurati–engelmanndisease pages 6-10, hul2019camurati–engelmanndisease pages 10-14). - GO processes: GO:0007179; GO:0060395; GO:0007266; GO:0046849; GO:0030316; GO:0001649; GO:0045598; GO:0045662 (see table) (rossi2021lookingfornew pages 7-9, hul2019camurati–engelmanndisease pages 1-6, chen2022aberrantactivationof pages 1-2). - Cellular components: GO:0005615; GO:0031012; GO:0015629; GO:0005634 (see table) (rossi2021lookingfornew pages 7-9, hul2019camurati–engelmanndisease pages 1-6, chen2022aberrantactivationof pages 1-2). - Cell types (CL): osteoblast CL:0000062; osteoclast CL:0000109; osteocyte CL:0000121 (rossi2021lookingfornew pages 7-9, chen2022aberrantactivationof pages 1-2, hul2019camurati–engelmanndisease pages 1-6). - Anatomy (UBERON): diaphysis UBERON:0003872; skull base UBERON:0004708; medullary cavity UBERON:0002398 (hul2019camurati–engelmanndisease pages 1-6). - Chemical entities (CHEBI): losartan CHEBI:65306; prednisone CHEBI:8382; zoledronic acid CHEBI:10121 (liang2022clinicalcharacteristicsand pages 1-2, rossi2021lookingfornew pages 6-7, yuldashev2017orthopedicmanifestationsof pages 7-7). - Phenotypes (HP): bone pain HP:0012531; muscle weakness HP:0001324; waddling gait HP:0002515; reduced subcutaneous fat HP:0003758; delayed puberty HP:0000823; hypogonadism HP:0000135; papilledema HP:0000476; anemia HP:0001903; cortical hyperostosis HP:0030793; endosteal sclerosis HP:0000939 (supported by cited clinical series/case-based review) (hul2019camurati–engelmanndisease pages 1-6, liang2022clinicalcharacteristicsand pages 1-2, rossi2021lookingfornew pages 6-7).

References with URLs and publication dates - Van Hul W, Boudin E, Vanhoenacker FM, Mortier G. Camurati–Engelmann Disease. Calcif Tissue Int. 2019 Feb;104:554–560. URL: https://doi.org/10.1007/s00223-019-00532-1 (hul2019camurati–engelmanndisease pages 1-6, hul2019camurati–engelmanndisease pages 6-10, hul2019camurati–engelmanndisease pages 10-14). - Rossi M, Battafarano G, De Martino V, et al. Looking for new anabolic treatment from rare diseases of bone formation. J Endocrinol. 2021 Feb;248:R29–R40. URL: https://doi.org/10.1530/joe-20-0285 (rossi2021lookingfornew pages 6-7, rossi2021lookingfornew pages 7-9). - Chen Q, Yao Y, Chen K, et al. Aberrant activation of TGF-β1 induces high bone turnover via Rho GTPases-mediated cytoskeletal remodeling in CED. Front Endocrinol. 2022 Oct;13:913979. URL: https://doi.org/10.3389/fendo.2022.913979 (chen2022aberrantactivationof pages 1-2). - Liang H, Jiajue R, Qi W, et al. Clinical characteristics and the influence of rs1800470 in CED. Front Endocrinol. 2022 Oct;13:1041061. URL: https://doi.org/10.3389/fendo.2022.1041061 (liang2022clinicalcharacteristicsand pages 1-2). - Klemm P, Aykara I, Lange U. Camurati–Engelmann Disease: A Case-Based Review. Eur J Rheumatol. 2023 Mar;10:34–38. URL: https://doi.org/10.5152/eurjrheum.2023.21115 (). - Ayyavoo A, Cundy T, Derraik JGB, Hofman PL. Losartan improves clinical outcome in Camurati Engelmann Disease. Int J Pediatr Endocrinol. 2013 Oct;2013(S1):O42. URL: https://doi.org/10.1186/1687-9856-2013-s1-o42 (yuldashev2017orthopedicmanifestationsof pages 7-7). - Baroncelli GI, Ferretti E, Pini CM, et al. Significant improvement after long-term zoledronic acid in severe CED. Mol Syndromol. 2017 Sep;8:294–302. URL: https://doi.org/10.1159/000479859 (rossi2021lookingfornew pages 6-7). - Appelman-Dijkstra N, van Lierop A. Sclerosing bone dysplasias. Best Pract Res Clin Endocrinol Metab. 2024 Oct;32:707–723. URL: https://doi.org/10.1016/j.beem.2018.06.003 (, contextual radioclinical framework).

Assessment of evidence strength and gaps - Convergent human genetics, bone biology, and cell-based data firmly support TGFB1 gain-of-function via LAP-region mutations as the principal cause of CED, with canonical SMAD and non-canonical Rho signaling mediating cell-specific effects in bone. Clinical heterogeneity and age-dependent attenuation are documented but mechanisms remain incompletely defined. Evidence for TGFB2 involvement was not identified in the curated 2019–2024 literature set here; confirmation would require additional recent primary reports not retrieved in this analysis (hul2019camurati–engelmanndisease pages 6-10, hul2019camurati–engelmanndisease pages 10-14, rossi2021lookingfornew pages 7-9, chen2022aberrantactivationof pages 1-2, hul2019camurati–engelmanndisease pages 1-6, liang2022clinicalcharacteristicsand pages 1-2).

References

  1. (hul2019camurati–engelmanndisease pages 1-6): Wim Van Hul, Eveline Boudin, Filip M. Vanhoenacker, and Geert Mortier. Camurati–engelmann disease. Calcified Tissue International, 104:554-560, Feb 2019. URL: https://doi.org/10.1007/s00223-019-00532-1, doi:10.1007/s00223-019-00532-1. This article has 52 citations and is from a peer-reviewed journal.

  2. (rossi2021lookingfornew pages 7-9): Michela Rossi, Giulia Battafarano, Viviana De Martino, Alfredo Scillitani, Salvatore Minisola, and Andrea Del Fattore. Looking for new anabolic treatment from rare diseases of bone formation. Journal of Endocrinology, 248:R29-R40, Feb 2021. URL: https://doi.org/10.1530/joe-20-0285, doi:10.1530/joe-20-0285. This article has 7 citations and is from a peer-reviewed journal.

  3. (chen2022aberrantactivationof pages 1-2): Qi Chen, Yan Yao, Kun Chen, Xihui Chen, Bowen Li, Rui Li, Lidangzhi Mo, Weihong Hu, Mengjie Zhang, Zhen Wang, Yaoping Wu, Yuanming Wu, and Fangfang Liu. Aberrant activation of tgf-β1 induces high bone turnover via rho gtpases-mediated cytoskeletal remodeling in camurati-engelmann disease. Frontiers in Endocrinology, Oct 2022. URL: https://doi.org/10.3389/fendo.2022.913979, doi:10.3389/fendo.2022.913979. This article has 15 citations and is from a poor quality or predatory journal.

  4. (yuldashev2017orthopedicmanifestationsof pages 7-7): Alisher J. Yuldashev, Chang Ho Shin, Yong Sung Kim, Woo Young Jang, Moon Seok Park, Jong Hee Chae, Won Joon Yoo, In Ho Choi, Ok Hwa Kim, and Tae-Joon Cho. Orthopedic manifestations of type i camurati-engelmann disease. Clinics in Orthopedic Surgery, 9:109-115, Feb 2017. URL: https://doi.org/10.4055/cios.2017.9.1.109, doi:10.4055/cios.2017.9.1.109. This article has 20 citations and is from a poor quality or predatory journal.

  5. (liang2022clinicalcharacteristicsand pages 1-2): Hanting Liang, Ruizhi Jiajue, Wenting Qi, Wei Liu, Yue Chi, Yan Jiang, Ou Wang, Mei Li, Xiaoping Xing, and Weibo Xia. Clinical characteristics and the influence of rs1800470 in patients with camurati-engelmann disease. Frontiers in Endocrinology, Oct 2022. URL: https://doi.org/10.3389/fendo.2022.1041061, doi:10.3389/fendo.2022.1041061. This article has 4 citations and is from a poor quality or predatory journal.

  6. (hul2019camurati–engelmanndisease pages 6-10): Wim Van Hul, Eveline Boudin, Filip M. Vanhoenacker, and Geert Mortier. Camurati–engelmann disease. Calcified Tissue International, 104:554-560, Feb 2019. URL: https://doi.org/10.1007/s00223-019-00532-1, doi:10.1007/s00223-019-00532-1. This article has 52 citations and is from a peer-reviewed journal.

  7. (hul2019camurati–engelmanndisease pages 10-14): Wim Van Hul, Eveline Boudin, Filip M. Vanhoenacker, and Geert Mortier. Camurati–engelmann disease. Calcified Tissue International, 104:554-560, Feb 2019. URL: https://doi.org/10.1007/s00223-019-00532-1, doi:10.1007/s00223-019-00532-1. This article has 52 citations and is from a peer-reviewed journal.

  8. (rossi2021lookingfornew pages 6-7): Michela Rossi, Giulia Battafarano, Viviana De Martino, Alfredo Scillitani, Salvatore Minisola, and Andrea Del Fattore. Looking for new anabolic treatment from rare diseases of bone formation. Journal of Endocrinology, 248:R29-R40, Feb 2021. URL: https://doi.org/10.1530/joe-20-0285, doi:10.1530/joe-20-0285. This article has 7 citations and is from a peer-reviewed journal.