CYTOMEGALOVIRUS PROPHYLAXIS AND TREATMENT FOLLOWING BONE-MARROW TRANSPLANTATION

OBJECTIVE: TO provide an overview of the role of cytomegalovirus (CMV) in the bone marrow transplant (BMT) population and update the current methods of prevention and treatment of CMV infection and disease, wit h emphasis on CMV interstitial pneumonia (CMV-IP). DATA SOURCES: The c urrent medical literature, including abstracts presented at recent nat ional and international meetings, is reviewed. References were identif ied by searching the MEDLINE database from January 1988 through June 1 994. The reference lists of the published studies and reviews obtained from the initial literature search were reviewed as well. STUDY SELEC TION: Data regarding the epidemiology of CMV, the risk factors associa ted with CMV infection and disease, as well as data on the prevention and the treatment of CMV infection and disease in the BMT population a re cited. Specific attention was focused on randomized, placebo-contro lled studies pertaining to the prevention of CMV infection and disease in CMV-immunoglobulin G positive recipients undergoing allogeneic BMT . Information from nonrandomized, placebo-controlled studies was inclu ded in the absence of stronger data. DATA EXTRACTION: Information cont ributing to CMV in the BMT population was reviewed. Data supporting an d disputing specific preventive and treatment modalities are presented . DATA SYNTHESIS: The incidence of CMV seropositivity in the general p opulation is high and while BMT becomes a widely accepted treatment mo dality, CMV reactivation and subsequent disease, especially CMV-IP, be comes a significant prognostic factor of morbidity and mortality. Even though antiviral agents such as ganciclovir and foscarnet can inhibit the viral replication in vivo, they have not been able to treat CMV-I P effectively. It has been suggested that CMV-IP is an immunopathologi c process that can cause irreversible damage, hence, the low efficacy of antiviral therapy and the associated high mortality. Immunomodulati ng agents such as intravenous immune globulin and cytomegalovirus hype rimmune globulin can increase the efficacy of antivirals in the treatm ent of CMV-IP. This further supports the postulated immunopathologic p rocess of this disease. The lack of understanding of the pathophysiolo gy of the disease compromised the efforts of treatment and led to the development of preventive interventions with antiviral and immunomodul atory regimens that resulted in a significantly lower incidence of inf ection and disease. As a result of current data, the Eastern Cooperati ve Oncology Group has published guidelines for the prevention and trea tment of CMV infection and disease. CONCLUSIONS: The prognosis of CMV disease in the BMT recipients has improved as a result of a wide varie ty of modifications in the management of BMT recipients. These include an increased understanding of the risk factors associated with CMV in fection, routine screening for CMV replication and excretion, and more effective prophylactic regimens. Still, more than half of the patient s who develop pneumonia will die, indicating that more studies are nee ded to increase the understanding of the pathophysiology and refine th e preventive and therapeutic regimens against CMV.