A Hidden Secondary Hyperparathyroidism: A Case Report

The secondary hyperparathyroidism is defined by an elevated parathyroid hormone (PTH) secondary to a decrease in calcemia. We report the case of a 15-year old female, followed for 3 years at the nephrology department for a nephrocalcinosis and which was addressed to us for the suspicion of a primary hyperparathyroidism. We noted in her personal history renal lithiasis. The physical examination found a tooth dystrophy with decalcified teeth and diffuse bone pain. First blood tests: calcemia: 85mg/L (80-105), phosphoremia: 55mg/L (40-70) and PTH: 147.6pg/ml high (15-65). Second blood tests: calcemia: 90.85mg/L (81-104), phosphoremia: 40.14mg/L (25-46) and PTH: 169.4pg/ml high (15-65). The blood tests were completed with a dosage of 25-hydroxy-vitamin D: 11ng/ml (deficiency), 24 hours calciuria : 198mg/24h (4.4mg/Kg/24h), high. The renal ultrasound showed a nephrocalcinosis. The patient received a vitamin D treatment than the normalizing of the vitamin D was obtained (30.53ng/ml) and PTH too (56pg/ml, standards: 15-80). The diagnosis of a primary hyperparathyroidism will be retained after eliminating a secondary hyperparathyroidism.