Acute cytomegalovirus infection superimposed on corticosteroid-naïve ulcerative colitis.

Most cases of cytomegalovirus (CMV) colitis that develop in patients with inflammatory bowel disease (IBD) are caused by a reactivation of a latent virus; acute CMV infections are rare. Treatment with immunosuppressive agents further increases the infection risk. Here, we present a 32-year-old man with acute CMV-mononucleosis and colitis, superimposed on corticosteroid-naïve ulcerative colitis (UC). The diagnosis was confirmed by a viral-like prodrome, positive CMV antigenemia (C7-HRP), a positive CMV IgM titer, the presence of atypical lymphocytes, mild transaminase elevation, and immunohistological detection of CMV positive cells in his colonic mucosa. Gancyclovir was intravenously administered, and all symptoms were improved.