[Enterohemorrhagic colitis: comparison of clinical and CT findings]

Abdominal precontrast CT was performed in 12 patients (5 males, 7 females, 29-81 years, mean age; 57.5 years) with enterohemorrhagic colitis due to Escherichia coli O157:H7. Mural thickening was recognized in the terminal ileum (11/12), cecum (12/12), ascending colon (11/12), transverse colon (7/12), descending colon (2/12), and rectosigmoid colon (1/12). Dirty fat sign, lymphadenopathy, and peritoneal fluid collection were seen in 11, 7, and 5 of the 12 cases, respectively. The CT appearance of enterohemorrhagic colitis is one of moderate to severe circumferential thickening. The bowel wall is heterogeneous because of submucosal edema and hemorrhage. The CT appearance is nonspecific, but the condition is mainly seen in the right colon. Precontrast CT is useful in the screening of enterohemorrhagic colitis, especially in mass outbreaks.