[Hypercalcemia in childhood. A boy with asymptomatic hypocalciuric hypercalcemia].

The diagnostic work-up of a patient with (familial) hypocalciuric hypercalcemia (FHH) is discussed. The patient showed no clinical signs of hypercalcemia. There were no indications of vitamin D intoxication. In the first degree family members no hypercalcemia was found. Physical examination was normal. In contrast to hyperparathyroidism, FHH is usually symptomless. Furthermore, FHH is characterized by a normal chloride/phosphate ratio, a normal, but relatively high, serum parathyroid hormone level, a relatively low urinary calcium excretion, a calcium-creatinine clearance ratio less than 0.01 and a normal cyclic AMP excretion.