Influenza-Related Colitis: A Summary on a Sparsely Mentioned Colorectal Disorder

Background: Influenza is an important viral respiratory disease. The disease mainly affects the respiratory organ. In severe cases, patients may die from this condition. To date, influenza remains a problematic infectious disease. The atypical manifestations of influenza are observable in clinical practice. The colorectal presentations of influenza are highly interesting. Methods and Evidence Acquisition: The authors searched and summarized clinical data from articles published in an international database regarding colitis in influenza. Results: Influenza-related colitis is an important medical condition that includes various types. Hemorrhagic colitis is a rare but possible clinical complication of influenza. In a patient with influenza-related colitis, lower abdominal pain, bloody diarrhea and hematochezia may be present. Severe colonic bleeding might occur for which hemostatic therapy is required. On the other hand, antiviral therapy is itself a possible cause of colitis. In a patient with influenza receiving oseltamivir, a possible adverse effect of this antiviral drug is hemorrhagic colitis. The problem might be acute; the patient usually complains of abdominal pain, diarrhea, and hematochezia after the first administration of oseltamivir. In addition to hemorrhagic colitis, ischemic colitis due to influenza is also observable. The patient might require colectomy, and this condition might even lead to death. Another possible colonic complication of influenza is colonic apoptosis secondary to influenzarelated fulminant hemophagocytic lymphohistiocytosis; the patient would have abdominal pain and skin rash. Conclusion: There is the possibility that colonic complications occur in any patient with influenza. The practitioner should recognize the possibility that there might be a colorectal manifestation in any patient with influenza.