Antenatal diagnosis of urinary tract abnormalities: correlation of ultrasound appearance with postnatal diagnosis.

A review was made of the natural history of the urinary tract abnormalities diagnosed antenatally in 18 fetuses in order to correlate the ultrasound appearance with subsequent postnatal diagnosis and prognosis. Unilateral disease, both obstruction and multicystic renal disease, was associated with a good prognosis. Bilateral dysplastic kidneys had a very poor prognosis. The antenatal ultrasound demonstration of bladder distention and/or hydronephrosis, however, does not always signify true obstruction of the urinary tract. This is important in view of the recent introduction of in utero interventions to preserve renal function and prevent pulmonary hypoplasia.