Crohn's disease of the anal region

In a previous report from this hospital (Morson and Lockhart-Mummery, 1959) the clinical features and pathology of the anal lesions of Crohn's disease were described. In that paper reference was made to several patients with anal fissures or fistulae, biopsy of which showed a sarcoid reaction, but in whom there was no clinical or radiological evidence of intra-abdominal Crohn's disease. The opinion was expressed that some of these patients might later prove to have intestinal pathology. This present contribution is a follow-up of these cases as well as of others seen subsequently. Involvement of the anus in Crohn's disease has been seen at this hospital in three different ways: 1 Patients who presented with symptoms of intestinal Crohn's disease who, at the same time, also had disease of the anus in the form of ulceration, fistulae, or fissure-in-ano. These patients were referred because of their intestinal symptoms, the involvement of the anus being an associated finding. 2 Patients referred to the hospital because of symptoms of anal disease but who were found also to have intestinal pathology on clinical or radiological investigation at that time. In this group the symptoms caused by the anal disease overshadowed those due to intestinal involvement or else the latter caused no symptoms. 3 Patients who presented with anal lesions which suggested Crohn's disease both clinically and histologically, who had at the time neither clinical nor radiological evidence of intestinal pathology. The object of this paper is to present the clinical features, pathology, and subsequent course of this last group of patients.