Urinary ascites in the newborn.

Seven cases of neonatal urinary ascites secondary to obstructive uropathy are reported. In 2 the bladder had perforated; in 4 there was perirenal extravasation; in 1 the site of leakage was not determined. A localised parenchymal perforation was found in 3 kidneys. Treatment was by temporary urinary diversion followed by operative relief of the obstruction. Six patients survive in good health; 1 infant died from causes unrelated to the ascites or the urinary tract. It is suggested that spontaneous urinary tract perforation with the development of ascites is often beneficial in the long term since it decompresses the obstructed system and lessens renal parenchymal damage.