Hydronephrosis in the neonate and young infant: current concepts.

Asymptomatic neonates with urological abnormalities that were discovered antenatally or during screening sonography in the neonatal period differ in a number of important ways from those presenting later with overt clinical signs and symptoms of urological disease. The accumulated experience with these neonates over the past decade has led to important advances in our understanding of the epidemiology, diagnosis, and management of congenital disorders of the urinary tract.