HIV-1 viral load: comparative evaluation of three commercially available assays in Argentina

Viral load (HIV-RNA copies per milliliter of plasma) has good correlation to prognosis considering progression to AIDS. The evaluation of commercial kits to measure viral load has become a need to find the most specific, sensitive and reproducible procedure to follow up HIV-infected patients. Hereby, a comparative analysis was done by using three different assays available in Argentina for quantitation of HIV-RNA in plasma. A plasma panel: 20 from HIV-1 infected individuals (9 asymptomatic and 11 symptomatic) and 9 from HIV-1 seronegative individuals was studied. Samples were run by Amplicor HIV-1 Monitor (Roche Diagnostic System, USA) Quantiplex HIV-1 RNA 2.0 Assay (Chiron Corporation, USA) and NASBA HIV-1 RNA QT (Organon Teknika, Holland). RNA was extracted from 0.2 ml of plasma for Amplicor, 0.1 ml and 1 ml of plasma for NASBA and, duplicates of 1 ml of plasma was centrifuged and pellet was used for bDNA assay no RNA extraction step. For a given specimen, a log difference of