Clinical and Molecular Spectrum of Infantile Hypercalcemia Type I: Insights Into CYP24A1 Variants
Authors' conclusion
Monoallelic or biallelic PVs in the CYP24A1 gene play a significant role in the aetiology of hypercalcemia and/or nephrocalcinosis/nephrolithiasis. Early genetic diagnosis is essential for guiding clinical management, particularly to avoid inappropriate vitamin D supplementation and to minimize the risk of long-term renal complications.
Study context
- Population
- Patients from six families with hypercalcemia, normal or elevated 25(OH)D3, suppressed or low-normal parathyroid hormone (PTH), and hypercalciuria and/or nephrocalcinosis6 families
- Participants
- 8 patients
- Outcome
- Clinical and molecular spectrum of IH with CYP24A1 PVs
Main finding
As reported in the abstract
- Age at presentation, median (range 5.0-44.4 months)
- 9.1 months
- Referred for vomiting
- 50%
- Born to consanguineous parents
- 4 (50%)
- Serum calcium, mean ± SD (median 3.5; range 2.8-4.6), elevated
- 3.6 ± 0.7 mmol/L
- 25(OH)D3, mean ± SD (median 845.4; range 89.9-2069), elevated
- 970.7 ± 880.5 nmol/L
- Hypercalciuria and/or nephrocalcinosis
- 87.5%
- Distinct CYP24A1 pathogenic variants (PVs) identified in eight patients
- 8
- Homozygous / compound heterozygous / heterozygous patients
- 2 / 4 / 2
Observational data: associations, not effects.
Further findings
1,25(OH)₂D₃ levels (available for three patients)
- Two patients with biallelic PVs had elevated concentrations; the monoallelic patient had a normal level
Mild hypercalcemia and/or nephrocalcinosis/nephrolithiasis in monoallelic parents
- Monoallelic parents affected
- 40%
Original publication
Clinical and Molecular Spectrum of Infantile Hypercalcemia Type I: Insights Into CYP24A1 Variants. Clin Endocrinol (Oxf). Published 1 December 2025. doi:10.
Composed by AI from the published abstract and checked against it. How Briefs are made →