Objective: To illustrate CT appearances of CDC in hospitalized patients with toxin assay indicant or endoscopic proven CDC.

Material and Method: Two reviewers independently evaluated the colonic abnormalities in the retrospectively identified patients with toxin assay indicant or endoscopic proven CDC that underwent abdominal CT between January 2006 and June 2009. The colonic abnormalities included wall thickening, wall enhancement, the accordion sign, pericolonic stranding, lymphadenopathy, ascites, gut obstruction, and associated findings such as small bowel involvement. They then compared the CT diagnostic findings with lab result and endoscopic findings

Results: Fifteen patients (in 897 patients) with toxin assay indicant or endoscopic proven CDC and underwent abdominal CT were included in the study. Colonic wall thickening (0.5-1.6 cm) and mild degree of pericolonic fat stranding are commonly found in this study. Eleven (73.3%) patients had pancolonic wall thickening and the remaining four (26.6%) had segmental involvement. Accordion sign was demonstrated in 11 (73.3%) patients. No small bowel thickening was detected. Contrast enhanced CT showed superior result to non-contrast enhanced CT for colonic wall thickness evaluation. Accordion sign were not different between contrast enhanced CT in patients that did not received oral/rectal contrast medium administration and non-contrast enhanced CT in patients that received adequate rectal contrast medium administration.

Conclusion: Patients taking a broad spectrum of antibiotic were found to have colonic wall thickening, a mild degree of pericolonic fat stranding, and accordion sign on CT scan. The doctor should be concerned with CDC.

Keywords: Clostridium difficile colitis, Pseudomembranous colitis, Antibiotic associated colitis