Association of self-limited cytomegalovirus colitis and shigellosis in an immunocompetent patient.

Cytomegalovirus (CMV) infection of the colon has been rarely reported in immunocompetent patients. Patients with severe acute illness or disseminated CMV infection have high mortality. In contrast, the patients with local injury of the colon due either to other gastrointestinal infections or to anal intercourse, who are otherwise healthy, usually have self-limited disease. The CMV infection is believed to be the bystander and may be treated conservatively. Concomitant CMV colitis and other gastrointestinal infections occur exclusively in immunosuppressed patients. We report, to our knowledge, the first case of co-infection of the colon with CMV and Shigella in an immunocompetent patient. The hypothesis is that the mucosal damage caused by Shigella infection may predispose the colon to secondary CMV invasion.