Mechanisms of cytomegalovirus disease

With the growing numbers of patients immunocompromised by AIDS or organ/bone marrow transplants, cytomegalovirus (CMV) infection has become a major cause for concern. Cytomegalovirus remains a leading cause of morbidity and mortality in these patient groups, despite the advent of new drugs and prophylactic strategies. During acute disease the virus can infect a variety of cell types, including cells of epithelial origin as well as endothelial and infiltrating inflammatory cells. Although the sites of viral persistence have not been identified, cells of the monocytic and endothelial linages are likely candidates for maintaining persistence in the human host. Immunosuppression commonly results in the reactivation of latent virus, and is followed by a variety of different disease processes. The mechanism through which CMV produces disease is most likely through direct tissue damage, but indirect immunological mechanisms may also play a role.