Ureteropelvic junction obstruction during the first year of life.

Over the past three years, 28 children less than one year of age, were operated on for ureteropelvic junction obstruction. Our results demonstrate that congenital hydronephrosis most commonly presents antenatally, and that early postnatal correction can be performed safely. The high surgical success rate, with a relatively short hospital stay (3-4 days), is attributed to early diagnosis, when the pelviureteral tissues are relatively healthy and nephron maturation is at maximum. The practice of delaying surgical correction of an obstructed hydronephrotic kidney on the basis of "stable" renal function is unwarranted, since it denies such kidneys their full potential for recoverability.