Renocolic fistula as a complication to xanthogranulomatous pyelonephritis

Four patients with xanthogranulomatous pyelonephritis were found to have renocolic fistulae. Coincidentally, the left kidney was involved in all four cases. All patients presented with renal mass. Two cases have had coexistent renal stones, one of them presented with massive upper gastrointestinal bleeding as a result of portal hypertension. Another patient had a history of Schistosomiasis. In none of the patients was the renal condition confidently diagnosed preoperatively, nor was the colonic fistula suspected. In all four patients, nephrectomy was performed together with resection of the involved colon followed by a satisfactory recovery. The possibility of a colonic fistula should be kept in mind as a complication to this rare renal condition in spite of the absence of colonic symptoms and normal finding in barium enema studies.