Renal and Vascular Phenotypic Characterization of Patients With Enamel Renal Syndrome Due to a Pathogenic Variant of the FAM20A Gene and Pathophysiological Study of Ectopic Calcifications

NCT07285421 | Not Yet Recruiting

• 3 other identifiers: APHP2406922024-A02589-3824.05810.000413
• Study Type: interventional
• Target: 30
• Locations: 1 country
• Sites: 2

Brief Summary

In the research, the investigators will characterize the renal and vascular damage and look for factors favoring the formation of calcification induced by enamel renal syndrome. Patients will undergo four investigations, as part of their routine care, to assess their renal impairment. Each investigation will require a day in the Physiology Department of the George Pompidou European Hospital. The 4 tests are designed to

• precisely measure your renal filtration capacity,
• evaluate your body's calcium and phosphate regulation,
• evaluate your capacity to regulate the elimination of water from the body
• assess your body's ability to regulate "acid" intake. As part of the research, an additional 20 ml blood sample and a urine sample will be taken during the other samples taken as part of routine care. Healthy volunteers will undergo blood and urine tests, dental X-rays and renal ultrasound. For healthy volunteers, the aim of the dental X-ray and renal ultrasound is to check that there are no dental or renal abnormalities, so as to rule out not only email-rein syndrome, but also any dental or renal abnormalities that might resemble it. The aim of blood and urine sampling is to measure various molecules that promote calcification or inhibit the calcification process, so as to be able to compare results obtained in healthy subjects with those obtained in patients with enamel renal syndrome. Each healthy subject will be selected to be matched by age and sex to each of the patients included in the study.

Conditions

Enamel Renal Syndrome

Keywords

FAM20A; enamel renal syndrome

Outcome Measures

Primary Outcomes (1)

• Glomerular filtration rate

  Glomerular filtration rate measurement by measure of renal 99mTc-DTPA clearance

  Up to 18 months

Secondary Outcomes (10)

• Comparison of urine proteome between patients and healthy volunteers

  Up to 18 months

• Maximal urine osmolality

  Up to 18 months

• Level of dp-uc MGP

  Up to 18 months

• Level of Fetuin A

  Up to 18 months

• Level of Osteoprotegerin

  Up to 18 months

Study Arms (2)

Healthy volunteers

OTHER

The control group will be made up of healthy volunteers, in order to provide a reference population, matched for the analyses carried out as part of the research, i.e. metabolome, proteome and plasma factors of mineralization.

Diagnostic Test: urinary proteome; Diagnostic Test: urinary metabolome; Diagnostic Test: Evaluation of plasma mineralization factors; Diagnostic Test: Renal ultrasound; Radiation: dental panoramic x-ray; Biological: Blood and urine minimal biology

Enamel Renal Syndrome Patient

EXPERIMENTAL

The population to be studied is a population of adult patients suffering from enamel renal syndrome with FAM20A mutation.

Diagnostic Test: urinary proteome; Diagnostic Test: urinary metabolome; Diagnostic Test: Evaluation of plasma mineralization factors

Interventions

urinary proteome DIAGNOSTIC_TEST

Volume 2 ml, with protease inhibitor made one time for each arm of the protocol

Enamel Renal Syndrome Patient; Healthy volunteers

urinary metabolome DIAGNOSTIC_TEST

Sample collected once in the protocol for each arm.

Enamel Renal Syndrome Patient; Healthy volunteers

Evaluation of plasma mineralization factors DIAGNOSTIC_TEST

Complementary plasma analysis during another blood sample collection for both arms

Also known as: Propensity score, Osteoprotegerin, dp-uc MGP, Fetuin A

Enamel Renal Syndrome Patient; Healthy volunteers

Renal ultrasound DIAGNOSTIC_TEST

Verification of normal renal morphology, absence of nephrocalcinosis

Healthy volunteers

dental panoramic x-ray RADIATION

Verification of normal dentition

Healthy volunteers

Blood and urine minimal biology BIOLOGICAL

Fasting blood: creatinine, blood ions (Na + K + Cl + CO2 + Proteins), calcium, phosphate, CBC (Complete Blood Count), liver function tests, lipid profile); Morning fasting urine: creatinine, calcium, phosphate, protein, urinalysis (ECBU)

Healthy volunteers

Eligibility Criteria

• Age: 18 Years - 90 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Informed patient who does not object to participating in the study
• Age ≥ 18 years
• Be affiliated to a social security scheme or be a beneficiary of such a scheme
• Able to understand the interest and constraints of the study
• Suffering from enamel-renal syndrome with a proven pathogenic variant of FAM20A

You may not qualify if:

• Pregnancy
• Breast-feeding
• Simultaneous participation in a therapeutic trial
• Patient under guardianship or curatorship
• Patient under court protection or family guardianship
• Patient under AME
• Enamel-renal syndrome with pathogenic variation in a gene other than FAM20A

Sponsors & Collaborators

• Assistance Publique - Hôpitaux de Paris: lead
• Fondation Université de Paris: collaborator
• Université de Liège: collaborator
• Institut Necker Enfants Malades: collaborator

Study Sites (2)

HEGP - clinical investigation center

Paris, 75015, France

Location

HEGP - physiology department

Paris, 75015, France

Location

MeSH Terms

Conditions

Amelogenesis imperfecta nephrocalcinosis

Interventions

Radiography, Panoramic; Blood Specimen Collection

Intervention Hierarchy (Ancestors)

Radiography, Dental; Radiography; Diagnostic Imaging; Diagnostic Techniques and Procedures; Diagnosis; Diagnosis, Oral; Dentistry; Specimen Handling; Clinical Laboratory Techniques; Punctures; Surgical Procedures, Operative; Investigative Techniques

Central Study Contacts

Cléo Bourgeois

CONTACT

0156095638; cleo.bourgeois@aphp.fr

Elise Bouderlique, MD

CONTACT

0156092866; elise.bouderlique@aphp.fr

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: NON RANDOMIZED
• Masking: NONE
• Purpose: OTHER
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: May 28, 2025
• First Posted: December 16, 2025
• Study Start: January 1, 2026
• Primary Completion (Estimated): October 30, 2029
• Study Completion (Estimated): October 30, 2029
• Last Updated: December 16, 2025

Record last verified: 2025-12

Data Sharing

• IPD Sharing: Will share
• Shared Documents: STUDY PROTOCOL, ICF
• Time Frame: Two years after the last publication
• Access Criteria: Data sharing requires approval from both the sponsor and the Principal Investigator (PI), contingent upon a scientific project and the PI team's scientific contribution. The founder may also participate in the decision-making process. Teams seeking to acquire IPD must engage with the sponsor and the IP team to discuss the scientific (and commercial) objectives, the specific IPD required, the preferred data transmission format, and the proposed timeline. The necessity to inform patients about data sharing or the obligation to undertake procedures with data protection authorities will be evaluated. The provision of data through the secure institutional tools of the sponsor AP-HP will be prioritized. Technical feasibility and financial support considerations will precede the obligatory formalization of a contract, including detailed description of data processing and general and specific security measures. The processing must adhere to the European General Data Protection Regulation

Locations

FR (2)