Norovirus gastroenteritis accompanied by ischemic colitis: a case report.

A 57-year-old woman was admitted to our hospital because of frequent bloody diarrhea, vomiting, and abdominal cramps. While the patient was diagnosed with norovirus gastroenteritis based on the presence by chance of positive norovirus antigen in the stool samples, endoscopic as well as pathological examinations demonstrated left-sided ischemic colitis. The patient soon recovered solely by supportive treatment. Although it is believed that patients with viral gastroenteritis do not develop bloody diarrhea, the present case suggested that conditions of viral gastroenteritis, such as intensified peristalsis, elevation of the intraluminal gut pressure, hypovolemia, and hemoconcentration might trigger ischemic colitis resulting in bloody diarrhea. Physicians should not exclude the diagnosis of viral gastroenteritis simply by depending on the presence of bloody diarrhea. Further studies to clarify the incidence of ischemic colitis in patients with viral gastroenteritis are indispensable.