Small bowel gas in severe ulcerative colitis.

The prognostic significance of excess small bowel gas on a plain abdominal radiograph has been assessed in 75 patients with severe attacks of ulcerative colitis requiring intravenous hydrocortisone. The radiographs were reviewed without knowledge of the subsequent outcome. Small bowel distension was defined as the presence of three or more loops of gas filled small bowel. Forty two patients responded to medical treatment and 33 underwent colectomy. The two groups were comparable for age, sex, and length of history. The surgical group had more extensive disease. Of those who did well on medical therapy, 18 (42.9%) had small bowel distension compared with 24 of 33 (72.7%) who failed medical therapy. The difference was significant (p less than 0.05, odds ratio = 3.55, 95% confidence interval of 2.27-5.87). Of the 24 patients with small bowel distension who came to surgery, five had more than four loops of gas filled small bowel. This degree of distension was not seen in any of the patients settling on medical therapy. Thus the presence of small bowel distension on a plain abdominal radiograph in a patient with severe ulcerative colitis may predict a poor response to medical therapy.