Ureteropelvic junction obstruction in newborns and infants.

Of 11 patients less than 1 year old with ureteropelvic junction obstruction 9 presented with an abdominal mass. The ideal method evaluation of such patients with an abdominal mass includes sonography followed by isotope renal scan if the mass is determined to be urinary in origin. Visualization by excretory urography in this age group is often impaired by poor renal concentrating ability and excessive bowel gas. Repair was achieved successfully using a nonintubated, nonstented, dismembered pyeloplasty in 10 of 13 kidneys. The average postoperative hospital stay for this group was 4.8 days. Three kidneys were diverted temporarily by nephrostomy, leading to a complication in 1 that required secondary repair. Average postoperative hospital stay in the diverted group was 15 days. Renal function was excellent following repair in all patients, suggesting that early repair is highly desirable in this age group.