Prevention and treatment of CMV infection after allogeneic bone marrow transplant.

CMV infection is the major infectious complication following bone marrow transplantation. It is most often related to reactivation of latent infection in patients who were CMV seropositive before BMT. The incidence and severity have recently been modified by the use of preventive and curative treatments. Prevention of CMV infection with the transfusion of seronegative blood products is useful only when donor and recipient are seronegative. High-dose acyclovir has been shown effective in one randomized study. A multicenter study is currently being performed in Europe to confirm this result. Intravenous gammaglobulins seemed to lower the number of patients who incur interstitial pneumonitis but not the incidence of viremia. They also decreased the incidence of gram-negative sepsis and severe GVH and improved survival. The treatment is based on the use of gancyclovir. Several studies show that gancyclovir is more effective in asymptomatic patients with viral isolation from blood or bronchoalveolar lavage. The addition to gancyclovir of high-dose gammaglobulin improves survival in symptomatic patients with interstitial pneumonitis. This progress in the prevention and treatment of CMV infection has improved the overall results of allogeneic bone marrow transplantation.