HHV-8 infection in patients with AIDS-related Kaposi's sarcoma in Brazil

The aims of the present study were to determine the prevalence of human her pesvirus type 8 (HHV-8) in HIV-positive Brazilian patients with (HIV+/KS+) and without Kaposi's sarcoma (HIV+/KS-) using PCR and immunofluorescence as says, to assess its association with to evaluate the performance of these t ests in detecting KS disease HHV-8 infection, and to investigate the associ ation between anti-HHV-8 antibody titers, CD4 counts and staging of KS dise ase. Blood samples from 66 patients, 39 HIV+/KS+ and 27 HIV+/KS-, were anal yzed for HHV-8 viremia in peripheral blood mononuclear cells by PCR and HHV -8 antigenemia for latent and lytic infection by immunofluorescence assay. Positive samples for latent nuclear HHV-8 antigen (LNA) antibodies were tit rated out from 1/100 to 1/409,600 dilution. Clinical information was collec ted from medical records and risk behavior was assessed through an intervie w. HHV-8 DNA sequences were detected by PCR in 74.3% of KS+ patients and in 3.7% of KS- patients. Serological assays were similar in detecting anti-LN A antibodies and anti-lytic antigens in sera from KS+ patients (79.5%) and KS- patients (18.5%). HHV-8 was associated with KS whatever the method used , i.e., PCR (odds ratio (OR) = 7.4, 95% confidence 16-25.61) or anti-LNA an d anti-lytic antibodies (OR interval (CI) = 2 = 17.0, 95%CI = 4.91-59.14). Among KS+ patients, HHV-8 titration levels correlated positively with CD4 c ounts (rho 0.48, P = 0.02), but not with KS staging. HHV-8 is involved in t he development of KS in different geographic areas worldwide, as it is in B razil, where HHV-8 is more frequent among HIV+ patients. KS severity was as sociated with immunodeficiency, but no correlation was found between HHV-8 antibody titers and KS staging.