Prophylaxis and treatment of cytomegalovirus infections in the bone marrow transplant recipient

Almost all viral infections after bone marrow transplant (BMT) are attributable to reactivation of latent DNA viruses, especially those of the Herpesvirus family. The first to reactivate is herpes simplex virus, followed by cytomegalovirus (CMV) with a reported peak incidence between 60 and 90 days in most studies and varicella zoster virus about three to 18 months after BMT. Epstein-Barr virus rarely causes detectable illness after BMT and reactivation is only seen in the most profoundly immunosuppressed. The most lethal infection and indeed the most prominent cause of failure overall after allogenic BMT is interstitial pneumonitis which is frequently due to CMV infection. This article considers prophylactic measures against viral infection and preliminary studies of regimens for the treatment of established CMV infections.