A young girl with recurrent calculosis and hypercalcemia

Mutations of the CYP24A1 gene are associated with alterations in the activity of the enzyme 25-OH-D-24-hydroxylase, resulting in dysfunction of the metabolism of vitamin D. This enzymatic deficiency may cause hypercalcemia, low parathyroid hormone levels, hypercalciuria, nephrolithiasis and nephrocalcinosis. The clinical case of a young woman with recurrent renal lithiasis, hypercalcemia and hypercalciuria is described. These features are linked to deficiency of the enzyme 25-OH-D-24-hydroxylase, therefore to a biallelic mutation of the CYP24A1 gene.