Antiviral treatment in patients with cytomegalovirus positive ulcerative colitis

Cytomegalovirus(CMV) is a common virus in patients with ulcerative colitis receiving immunosuppressive drugs. Many studies suggested that CMV infection is an exacerbating factor in patients with ulcerative colitis. The role of CMV in exacerbations of ulcerative colitis has been discussed. One of studies starting this discussion is an article entitled "CMV positive ulcerative colitis: A single center experience and literature review" by Kopylov et al. However, we think that there are some points that should be emphasized about the study. Especially, the small number of patients in the study has led to meaningless results. Large controlled prospective trials are needed to clarify the benefit of antiviral therapy for active ulcerative colitis patients.