Neonatal urological ultrasound: diagnostic inaccuracies and pitfalls.

Ninety one patients with urinary tract abnormalities diagnosed before birth were reviewed. Diagnoses based on prenatal and postnatal ultrasound scans alone were compared with the final diagnoses after full urological investigations, with operative or necropsy confirmation in 79 cases. The results confirmed that ultrasound examination before birth usually detects nonspecific abnormalities and although scanning after birth is more accurate it is not absolutely reliable. A diagnosis of "multicystic kidney' made on ultrasound scan alone is especially prone to error. Such mistakes can be avoided if full urological investigation is undertaken in every case.