VIRUS BURDEN IN LYMPH-NODES AND BLOOD OF SUBJECTS WITH PRIMARY HUMAN-IMMUNODEFICIENCY-VIRUS TYPE-1 INFECTION ON BITHERAPY

At present, it is not known whether undetectable plasma viremia corres ponds to an absence of human immunodeficiency virus type 1 (HIV-1) rep lication in lymphoid tissues. This issue has been explored in 11 subje cts with primary HIV-I infection treated with zidovudine plus didanosi ne by evaluating virologic markers in blood and lymphoid tissues 9-18 months after initiation of treatment. These markers include plasma vir emia, measured with a sensitive assay with a detection limit of 20 HIV -1 RNA copies/mL, infectious virus titers and proviral DNA in lymph no de mononuclear cells, and HIV-1 RNA in lymphoid tissue. Five subjects had plasma viremia <20 copies/mL and showed no evidence of viral repli cation in lymphoid tissue. Six subjects had both detectable plasma vir emia and evidence of HIV-1 RNA in lymphoid tissue. The results indicat e that absence of detectable HIV RNA in lymphoid tissue is associated with viremia levels of HIV-1 RNA <20 copies/mL.