outcome of antenatally diagnosed hydronephrosis

15 patients with an antenatal diagnosis of hydronephrosis were evaluated with a false positive rate of 4%. 8 patients had bilateral and 7 unilateral hydronephrosis. The commonest final diagnosis in patients with bilateral dilatation was posterior urethral valve [43%] and when unilateral, pelviureteric junction obstruction [57%]. 4 patients [27% of total] had normal physical examination at birth, abnormalities only being detected on investigations. All patients had eventual normal renal function