Viral load of human herpesvirus 8 in peripheral blood of human immunodeficiency virus-infected patients with Kaposi's sarcoma

Viral load is an important marker of activity of viral diseases for a numbe r of viruses. We wished to evaluate whether the viral load of human herpesv irus 8 (HHV-8) in peripheral blood was a consistent feature of Kaposi's sar coma (KS) patients and whether the viral load correlated with human immunod eficiency virus (HIV) RNA levels, CD4 counts, and/or the HHV-8 seroreactivi ty. Fifty-four consecutive plasma samples from 14 patients with KS were eva luated for HHV-8 viral load by quantitative real-time PCR. Samples were ana lyzed at the start of highly active antiretroviral therapy (HAART) and at d ifferent intervals during treatments. The median HHV-8 DNA load before HAAR T treatment was 8,998 (ranging from 170 to 40,100) copies/ml and 12,270 (ra nging from 40 to 142,575) copies/ml during HAART. There were both increasin g and decreasing trends. There was an association between HHV-8 DNA and HIV RNA viral loads (odds ratio [OR] = 5.40; 95% confidence interval [95% CI], 1.54 to 18.98) and between HHV-8 viral load and CD4 cell counts (OR = 7.24 ; 95% CI, 1.30 to 40.35). High HHV-8 viral load was also correlated with th e titers of antibodies to the lytic HHV-8 antigen detected with immunofluor escence (P < 0.01), but not with antibodies to the latent HHV-8 antigen. In conclusion, we found that HHV-8 viremia in KS is associated with HIV viral load, CD4 cell counts, and lytic HHV-8 serological reactivity. HHV-8 viral load monitored by real time PCR might be useful for determination HHV-8 vi ral load during the follow-up of KS patients.