Abstract
Cytomegalovirus (CMV) is a ubiquitous human herpes virus, which, after often asymptomatic primary infection, establishes a lifelong latent infection that can periodically be reactivated in both immunocompetent and immunosuppressed carriers. Whereas the diagnostic approach in case of a suspicion of CMV reactivation is well defined, the indication for antiviral therapy can often only be made in the context of an extent of organ involvement, the immune status, and comorbidities of the patient. This article reviews the epidemiology, diagnosis, and therapy of CMV reactivation with a focus on inflammatory bowel diseases and potentially different diagnostic and therapeutic approaches in Asia and the Western world.