ESPE Abstracts

Objective: To present a patient with hypercalcemia caused by a parathyroid adenoma and a deletion of the VDR gene.

Case clinic: The case is that of a 13-year-old male who presented with hypercalcemia, muscle weakness, nephrocalcinosis, two pathological fractures and a family history of nephrocalcinosis. Physical examination was unremarkable, except the presence of a fracture of the left femur. Laboratory findings: Total serum calcium 14.4 mg/dl (8.5 a 10.2 mg/dL), ionic calcium 4.24 mmol/l (1.20-1.38 mmol/l), serum phosphate 3.3 mg/dl (4.0 a 7.0 mg/dl.), urinary calcium normal, serum PTH 233 pmol/l (10 a 55 pg/mL), alkaline phosphatase 390 U/l (86-315 U/L.), 25 (OH)D 18 ng/ml (20 y 40 ng/ml), 1-25(OH)D 189 pg/ml (15,2 – 90,1 pg/ml). Left femoral x-ray with fracture. Bone densitometry showed vertebral and hip osteoporosis. Scintigraphy with sestamibi revealed a right lower parathyroid adenoma. A heterozygous C2 T>C mutation of the VDR gene was found. The parathyroid adenoma was removed surgically with resolution of the hypercalcemia.

Conclusion: VDR Gene mutations can lead to secondary parathyroid adenomas and hypercalcemia.