[Asymptomatic, excessive hypercalcemia n a 12-year-old boy].

A cervical lymph node enlarged since 3 weeks was to be removed in a 12-year-old boy, whose only complaint was slight fatigue. Routine screening revealed hypercalcemia of 7.3-8.1 mval/l. This rose to 9.2 mval/l despite furosemide-induced high fluid turnover and prednisone while diagnostic evaluation proceeded. Serum phosphate was low consistently. Malignancy, vitamin D-intoxication, immobilisation and familial conditions could be ruled out as causes. Highly elevated serum-parathormone levels inspite of hypercalcemia, and ultrasonography of the neck were the most helpful evidence of a parathyroid adenoma. Calcitonin was effective in lowering serum-calcium to 6-7 mval/l preoperatively.