pattern of inheritance of idiopathic hypercalciuria in two families

idiopathic hypercalciuria is a leading cause of frequency-dysuria syndrome in childhood. different modes of inheritance have been suggested in this disease. this article presents the occurrence of idiopathic hypercalciuria in all children of two families. in the first family, a 5.5 year old girl with a history of renal stones and dysuria due to hypercalciuria, had two involved brothers and one sister. in the second family, hypercalciuria and medullary nephrocalcinosis were detected in two siblings who were admitted for polyuria and dysuria. idiopathic type of hypercalciuria was diagnosed in these two families by normal laboratory exams and exclusion of other causes of normocalcemic hypercalciuria. according to the involvement of all offsprings (both sexes) in these two families, it is suggested that idiopathic hypercalciuria is an autosomal dominant disease with complete penetration.