Familial pelviureteric junction hydronephrosis and its association with a duplex pelvicaliceal system and vesicoureteric reflux. A family study.

The incidence of pelviureteric junction (PUJ) hydronephrosis and a bifid pelvicaliceal collecting system was determined in the parents and siblings of 19 patients with PUJ hydronephrosis. The high incidence of hydronephrosis in first degree relatives supports the hypothesis that PUJ hydronephrosis is inherited by an autosomal dominant gene of variable penetrance. There is a genetic inter-relationship between PUJ hydronephrosis and a bifid pelvicaliceal system and therefore indirectly between vesico-ureteric reflux and paraureteric diverticula. Ultrasound screening of the children of adults with PUJ hydronephrosis may lead to earlier diagnosis and treatment, thus preventing renal damage.