Evaluation of the NucliSens EasyQ assay in HIV-1-infected individuals in 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 >750000 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 (log10 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 log6IU 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.
Stevens
W
W
Department of Molecular Medicine and Haematology, School of Pathology, Faculty of Health Sciences, University of Witwatersrand and the National Health Laboratory Service, South Africa. wendy.stevens@nhls.ac.za
Wiggill
T
T
Horsfield
P
P
Coetzee
L
L
Scott
L E
LE
D000163:Acquired Immunodeficiency Syndrome / Q000821:virology*; D015497:HIV-1 / Q000302:isolation & purification*; D006801:Humans; D012367:RNA, Viral / Q000032:analysis*; D015203:Reproducibility of Results; D012189:Retrospective Studies; D019562:Viral Load
D012367:RNA, Viral