Background: The appendix is occasionally involved in patients with distal ulcerative colitis. This study investigated the clinical significance of patchy involvement at the appendiceal orifice in ulcerative colitis.
Methods: Colonoscopy was performed in 40 patients with active distal ulcerative colitis of mild to moderate severity. Patients were divided into 2 groups based on the presence or absence (positive or negative) of involvement at the appendiceal orifice at colonoscopy. Clinical activity, histologic grade of inflammation, and subsequent clinical course were compared between patients who were positive (appe(+)) and negative (appe(-)).
Results: Twenty-three patients had involvement at the appendiceal orifice (reddish mucosa with mucinous exudate). The proximal-most extent of involvement by ulcerative colitis, the endoscopic grade, and clinical activity were not different between appe(+) and appe(-) groups. However, histologic grade of inflammation in the ascending colon was higher in the appe(+) group than in the appe(-) group. The endoscopic remission rate at 12 months was higher in the appe(+) group than in the appe(-) group (84% vs. 40%, p < 0.05).
Conclusions: In patients with distal ulcerative colitis, involvement at the appendiceal orifice may be indicative of histologically active disease, which responds reasonably well to pharmacotherapy.