RESUMO
The performance of the Abbott m2000rt RealTime HIV-1 assay (RealTime HIV-1) with manual sample preparation was compared against the ROCHE COBAS AmpliPrep/AMPLICOR HIV-1 MONITOR Test v1.5 (CAP/CA HIV-1) using samples collected from 100 donors infected with HIV and 20 donors not infected with HIV in northern Tanzania where HIV-1 subtypes A, C, D, and their recombinant forms predominate. The RealTime HIV-1 appeared to have more within-run variability at high HIV-1 RNA concentrations, but total assay variability over the dynamic range tested was within the manufacturer's claim of <0.3 SD copies/mL. Accuracy studies showed 100% concordance for positive and negative values. When continuous values were examined, CAP/CA HIV-1 yielded higher values than the RealTime HIV-1 at higher nominal HIV-1 RNA concentrations. The RealTime HIV-1 assay showed excellent linearity between 2.5 and 7.0 log copies/mL. Of negative samples, 100% showed negative results, and >95% of samples with nominal concentrations of 40 copies/mL were detected at > or = 40 copies/mL by RealTime HIV-1. Manual sample preparation may contribute to higher total assay variability. This study suggests that the Abbott m2000rt RealTime HIV-1 assay with manual sample preparation is an acceptable and feasible alternative to the conventional ROCHE COBAS AmpliPrep/AMLICOR HIV-1 Monitor v1.5 assay and that the RealTime HIV-1 assay performs well on samples from East Africa.
