Human herpesvirus-6 and the course of human immunodeficiency virus infection

The aim of this study is to investigate the relationship between human herpesvirus type 6 (HHV-6) and cytomegalovirus (CMV) infection and progression of AIDS disease. A group of 52 HIV-1-seropositive patients was examined for HHV-6 DNA expression in peripheral blood mononuclear cells and for CMV DNA in serum. We found that 21.1% (n = 52) and 12% (n = 25) of them tested positive for HHV-6 and CMV DNA, respectively. In contrast, only 3.3% (n = 29) and 0% (n = 29) of control healthy HIV-1-seronegative donors tested positive for HHV-6 and CMV, respectively. In light of these results, the possible role of HHV-6 as a cofactor in AIDS development has also been assessed by closely following, over 6 years, the course of an HIV-1-seropositive person who had a dramatic loss in the total number of CD4+ cells along with a spontaneous production of HIV-1 p24 antigen in vitro and who also showed progression to AIDS when coinfected with HHV-6. These observations have spurred our prospective analysis of the possible clinical significance of coinfection with HHV-6 and HIV.