Fatal adult case of severe lymphocytopenia associated with reactivation ofhuman herpesvirus 6

It has been suggested that immunosuppression associated with human herpesvi rus 6 (HHV-6) infection is a result of functional impairment or direct dest ruction of immunological cells. The ability of the virus to infect and dest roy lymphocytes may cause progressive immunodeficiency in an infant with pr imary HHV-6 infection. An adult patient is described who had a fatal cytome galovirus (CMV) infection due to severe and prolonged lymphocyte depletion associated with HHV-6 reactivation. The HHV-6 antibody titers were increase d significantly after reactivation, and the virus was isolated from his per ipheral blood mononuclear cells. The quantity of both HHV-6 and CMV DNA was determined by using real-time PCR in plasma samples collected serially. HH V-6 DNAemia persisted for 1 month, which started just 1 week after the onse t of lymphocytopenia. In contrast to HHV-6, CMV DNAemia was detected in the terminal phase of the illness. Thus, HHV-6 reactivation may have been the cause of the severe lymphocyte depletion and fatal CMV infection. (C) 2002 Wiley-Liss, Inc.