Evaluation of the NucliSens EasyQ assay in HIV-1-infected individuals in South Africa
Journal of Virological Methods
Dept. of Molec. Med. and Haematology, School of Pathology, Fac. Hlth. Sci., Univ. W., York Rd., Parktown 2193, South Africa
We compared the performance of the NucliSens EasyQ assay (bioMerieux) combined with the manual NucliSens miniMag extraction methodology to the Roche Cobas Ampliprep/Standard Amplicor Monitor methodology (Roche Diagnostics) for HIV-1 RNA quantitation in HIV-1-infected individuals in South Africa. Plasma samples (284) from HIV sero-positive patients at different stages of infection were analyzed. The distribution of results was typical of the clinical samples received at the laboratory where 20% have viral load results <400 copies/ml (2.6 log) and 18% have viral load results >750 000 copies/ml (5.8 log) using the Roche Amplicor Monitor standard assay. All statistical analyses were performed using log10-transformed values for all the variables in the analyses, i.e. log10EasyQIU/ml, and log10RNA (log 10 copies/ml, Amplicor). Roche values were converted from RNA copies per ml to IU/ml by multiplying the Roche value by 0.51. HIV RNA levels quantitated by the NucliSens EasyQ assay correlated significantly with those of the Roche Cobas Amplicor Monitor assay (r = 0.874, p < 0.0001). Reproducibility of the NucliSens EasyQ assay in the log 6 IU range yielded CV variance of 1.3-2.84% for two well-trained technologists. In addition, a retrospective evaluation of the performance of the NucliSens EasyQ assay in 102 runs (2448) samples was conducted in the laboratory over a 4-month interval. Factors considered during this evaluation included time taken to perform the assay, volume requirements, number of required repeats, potential for contamination. © 2004 Elsevier B.V. All rights reserved.
virus RNA; article; assay; blood sampling; controlled study; correlation analysis; extraction; human; Human immunodeficiency virus 1; intermethod comparison; laboratory test; priority journal; quantitative analysis; reproducibility; South Africa; statistical analysis; virus load; Acquired Immunodeficiency Syndrome; HIV-1; Humans; Reproducibility of Results; Retrospective Studies; RNA, Viral; Viral Load; Human immunodeficiency virus 1