[The foreign body granuloma after pyeloplasty: report of a case].

We report a rare case of foreign body granuloma on plain catgut which developed after Anderson-Hynes pyeloplasty for obstruction of the ureteropelvic junction in a 3-year-old boy. We use plain catgut as the suture material on pyeloplasty and seldom experience such a complication. Regarding suture material on pyeloplasty, excessive sutures intended to make anastomosis water-tight to prevent urinary leakage should be avoided in children because they are apt to form foreign body granuloma.