Fig. 3

Distribution of gastrointestinal ulcer in 273 patients with BD. Endoscopy showed that gastrointestinal ulcer in patients with BD may occur in any part of the alimentary tract from the esophagus to the rectum. The main foci of the gastrointestinal ulcer in BD patients are typically the isolated terminal ileum and colon. The numbers of BD patients with gastrointestinal ulcers isolated to ileocecal region, ascending colon, transverse colon, descending colon, sigmoid colon and rectum were 106, 2, 3, 1, 2 and 8, respectively. However, isolated upper gastrointestinal tract involvement, including the esophagus, gastric body, gastric body, gastric antrum, and duodenum, lesions are also detected as well, with a relatively high frequency 30.76% (84/273). 24 patients with multiple segment involvement