Edwardsiella tarda, a member of the family Enterobacteriaceae found in aquatic environments, is an unusual cause of human disease. We herein report a case of acute colitis caused by E. tarda. A 73-year-old man who had a poorly controlled diabetes mellitus underwent, further examination of his digestive system by our hospital from his home doctor. He had right flank discomfort and soft stool on the previous day. Abdominal ultrasonography revealed focal wall thickening of the ascending colon. Colonoscopic examination revealed mucosal redness, swelling, and submucosal tumor-like elevated lesions. The histopathological finding revealed erosive colitis. In the stool culture, E. tarda was identified, and no other pathogenic bacteria were detected. Abdominal computed tomography revealed focal wall thickening from the cecum to the ascending colon. His symptoms improved with conservative therapy.
