Tuberous sclerosis with striking renal involvement in a family.

We describe five cases of tuberous sclerosis in members of one family, all having renal involvement but with differences in age of onset and mode of presentation. Clinical, laboratory, and pathologic features helpful in diagnosing this condition and in distinguishing it from polycystic kidney disease and renal neoplasms are stressed. Tuberous sclerosis should always be considered in differential diagnosis of patients with multiple cystic renal lesions, particularly when age of onset of symptoms ranges from infancy to adult life in different members of one family. Absence both of specific glomerular or tubular lesions in ultrastructure and of major abnormalities in renal tubular function supports the existing concept that replacement of nephrons by hamartomatous lesions is the cause of progressive renal failure.