Human immunodeficiency virus 1 (HIV-1) infection is most commonly transmitted by sexual contact across mucosal surfaces. Information on concordance in drug resistance profile between blood plasma and anogenital compartments in resource-limited settings is limited. We aimed to determine discordances in genotypic drug resistance-associated mutations (DRAMs) between blood plasma and semen or rectal secretions among newly diagnosed, antiretroviral therapy (ART)-naive, HIV-1-infected Thai men who have sex with men (MSM). Blood plasma, semen, and rectal secretions of HIV-1-infected Thai MSM enrolled from the Test and Treat cohort were tested for genotypic mutations in the reverse transcriptase and protease genes. Seven participants with baseline DRAMs in blood plasma were included in this analysis. In anogenital samples, HIV-1 RNA could be fully amplified for DRAMs assessment in semen from three participants and in rectal secretions from four participants. DRAMs were identified in semen from two of three participants and in rectal secretions from four of four participants. Three participants had DRAMs in anogenital compartments that were not detected in blood plasma-one had DRAMs in semen that was not detected in blood plasma (I54FI) and two had DRAMs in rectal secretions that was not detected in blood plasma (I47IM; K70N, L74I, Y115F, M184V, K103N, V108I, and H221Y). Discordance in DRAMs between blood plasma and anogenital compartments is not uncommon among newly diagnosed, ART-naive, HIV-1-infected Thai MSM. Monitoring of drug-resistant virus in these vector compartments is warranted particularly as pre-exposure prophylaxis and treatment as prevention are increasingly used as the mainstay strategies to end the AIDS epidemic.
Keywords: HIV-1; compartmentalization; genotype; rectal secretions; resistance; semen.