BACKGROUND It remains controversial whether or not cytomegalovirus infection in patients with active ulcerative colitis reflects a nonpathogenic colonization or a pathogenic disease warranting antiviral therapy.

GOALS The aim of this study was to determine the prevalence of cytomegalovirus infection in patients with active ulcerative colitis and the therapeutic efficacy of ganciclovir against cytomegalovirus infection in patients with steroid-refractory ulcerative colitis.

STUDY A prospective, multicenter study was conducted in 72 patients with moderate-to-severe ulcerative colitis who were treated with intravenous steroids. The presence of cytomegalovirus was evaluated serologically and histopathologic examination, including immunohistochemical staining. In patients with steroid-refractory ulcerative colitis, cytomegalovirus infections were treated with intravenous ganciclovir. In patients with steroid-responsive ulcerative colitis, steroid therapy was continued irrespective of cytomegalovirus infection.

RESULTS The evidence of cytomegalovirus infection was found in 31 patients (43%) with moderate-to-severe active ulcerative colitis. In patients with steroid-refractory ulcerative colitis, the cytomegalovirus infection rate increased to 67% (14 of 21). No significant clinical and endoscopic differences existed between patients with and without a cytomegalovirus infection; however, the amount of steroids used during the flare-up period was significantly higher in patients with a cytomegalovirus infection (P = 0.013). Eleven of 14 patients (79%) with steroid-refractory ulcerative colitis and a cytomegalovirus infection improved with ganciclovir treatment. Cytomegalovirus infections in the steroid-responsive group (17 of 31) did not require ganciclovir therapy.

CONCLUSIONS Cytomegalovirus infections are frequently observed in patients with moderate-to-severe ulcerative colitis, especially steroid-refractory ulcerative colitis. Ganciclovir was effective in patients with steroid-refractory ulcerative colitis who had a cytomegalovirus infection.