A case of a renocolic fistula associated with left staghorn calculus

Abstract

A 57-year-old woman who had been treated for left staghorn calculus in the department of urology in our hospital as an outpatient was seen at our hospital for close exploration because stool guaiac tests were positive at a mass examination. Fiberoptic colonoscopy disclosed a tumor encircling the entire lumen of the descending colon with a part of ulceration. Barium enema showed leakage of barium from the descending colon tumor to the outside of the intestine. Contrast-enhanced abdominal CT scan revealed strongly contracted left staghorn calculus and chronic inflammation in the periphery of the kidney, to which the descending colon which had the thickened wall was adjacent. Accordingly left hemicolectomy associated with left nephrectomy was performed with a suspected diagnosis of a renocolic fistula in which a possibility of malignancy could not be ruled out. During surgery, we saw that the renal arteries and veins had already degenerated and contracted due to severe adhesions from the surroundings of the left kidney to the left diaphragm. Thus we had great difficulties in the identification and dissection between them, and performed an “en-bloc” resection without dissecting the adhesions between the intestine and renal fascia. The resected material showed a fistula from the intestine to the superior calyx. Histopathologically there were the extensively contracted kidney and changes with fibrous proliferation surrounding of it and both acute and chronic inflammatory changes coexisted in the renal pelvis. Hyperplastic change was identified on the colonic mucosa. The patient temporarily developed paralytic intestinal obstruction after the operation, but was discharged very much improved by conservative therapy on the 15^th postoperative day.
Renocolic fistula is a comparatively rare entity and a total of 48 cases, including our case, have been reported in Japan as far as we could review.