Resistance to antiretroviral drugs in treated and drug-naive patients in the Democratic Republic of Congo.

Background: We studied virological outcome and drug resistance in patients on antiretroviral therapy (ART) in health care centers in the Democratic Republic of Congo and looked for the presence of drug resistance in antiretroviral-naive patients attending the same clinics.

Methods: In 2008, we conducted a cross-sectional survey among patients on ART for ≥ 12 months in 4 major cities [Kinshasa (n = 289), Matadi (n = 198), Lubumbashi (n = 77), and Mbuji-Mayi (n = 103)]. Genotypic drug resistance tests were done with an in-house assay on samples with viral load >1000 copies/mL.