Abscess and fistulae in Crohn's disease.

In a series of 360 patients with Crohn's disease 18% have developed a complication of abscess and/or fistula. Both complications can be spontaneous but more commonly occur in patients who have had a previous operation. There is a high incidence of fistula after laparotomy without resection of diseased bowel. Simple drainage of an abscess is usually followed by a fistula and fistulae do not close spontaneously. The optimal surgical treatment for fistula and for deep abscess is excision in continuity with the diseased segment of intestine.