[Circulating metabolites of vitamin D in 14 children with hypercalcemia]

Circulating vitamin D metabolite concentrations, i.e. 25-(OH)D, 24,25-(OH)2D, 1,25-(OH)2D have been assayed in 14 hypercalcemic children. Results are as follows: a) Children with vitamin D intoxication (n = 2) had elevated serum 25-(OH)D and 24,25-(OH)2D concentrations but their 1,25-(OH)2D concentrations were similar to those found in normocalcemic children (10-110 pg/ml); b) Children with familial idiopathic hypercalcemia and hypocalciuria (n = 5), children with hypercalcemia and either Bartter's syndrome (n = 1), hemangiomatosis (n = 1), osteopetrosis after medullary graft (n = 1), also had 1,25-(OH)2D concentrations in the normal range; c) In contrast, 1,25-(OH)2D were elevated (160-470 pg/ml) in the four children with severe idiopathic hypercalcemia and elfin facies.