Association of antiretroviral therapy with detection of HIV-1 RNA and DNA in the anorectal mucosa of homosexual men

Objective: To determine whether combination antiretroviral therapy is assoc iated with reduced detection of HIV-1 RNA and DNA in the anorectal mucosa o f men who have sex with men (MSM). Design: Cross-sectional study of 233 MSM recruited from community and clini c sites in Seattle, Washington between July 1996 and December 1997. Methods: HIV-1 RNA and HIV-1 DNA were detected in anorectal swab specimens by polymerase chain reaction amplification assays. Results: HIV-1 RNA was detected significantly less often in anorectal speci mens from users of combination antiretroviral therapies, whether a protease inhibitor was received (15/89; 17%) or not (16/53; 30%), than in men not r eceiving therapy (43/88; 49%) (P < 0.001, P = 0.03, respectively). In contr ast, HIV-I DNA was detected only slightly less frequently in anorectal spec imens obtained from men receiving protease inhibitors (35/81; 43%) or rever se transcriptase inhibitors alone (22/48; 46%) than in specimens from men n ot receiving therapy (45/78; 58%) (P = 0.07, P = 0.20, respectively). Among men with < 50 copies HIV-1 RNA/ml plasma, detection of HIV-1 RNA in anorec tal specimens was rare (1/54; 2%) but detection of HIV-1 DNA was common (14 /50; 28%). Conclusions: Combination antiretroviral therapy is associated with reductio ns in HIV-1 RNA, but HIV-1 DNA remains detectable in the anorectal canal of almost half of MSM receiving such therapy. Condom use during anal intercou rse should be encouraged, regardless of plasma viral load response to poten t antiretroviral therapy. (C) 2000 Lippincott Williams & Wilkins.