Spontaneous ureterocolic fistula: a rare complication of colonic diverticular disease.

Spontaneous ureterocolic fistula is rare and usually caused by urinary calculi. We present the fifth reported case of spontaneous ureterocolic fistula caused by diverticular disease of the colon. Review of these cases revealed a preponderance of women (3:1 ratio), with mean age of 77 years. These patients may have a protracted course before an accurate diagnosis is made (up to 10 years) because of the typical vague presentation. Urologic symptoms predominate, especially urinary tract infection (100%), fecaluria (75%), and abdominal (75%) or flank pain (50%). Barium enema is the most reliable diagnostic test in demonstrating the fistula (75%) compared with intravenous pyelogram (33%) or retrograde pyelogram (25%). The left ureter is usually involved (75%). Surgical intervention is generally directed towards resection of the diseased bowel with primary anastomosis when feasible. Surgical manipulation of the urinary system is unnecessary except for removing a non-functioning, infected kidney. Results of surgery were excellent, with 100 per cent cure and one unrelated mortality on long term follow-up. We recognize the potential for increase in this type of internal fistula, given the increasing lifespan and the established increase in incidence of colonic diverticular disease with advancing age. The correct diagnosis can often be determined preoperatively (75%), and surgical intervention is routinely successful.