TY - JOUR
T1 - Use of an HIV-1 reverse-transcriptase enzyme-activity assay to measure HIV-1 viral load as a potential alternative to nucleic acid-based assay for monitoring antiretroviral therapy in resource-limited settings
AU - Iqbal, H. Syed
AU - Balakrishnan, P.
AU - Cecelia, Anitha J.
AU - Solomon, Suniti
AU - Kumarasamy, N.
AU - Madhavan, Vidya
AU - Murugavel, K. G.
AU - Ganesh, Aylur K.
AU - Solomon, Sunil Suhas
AU - Mayer, Kenneth H.
AU - Crowe, Suzanne M.
PY - 2007/12
Y1 - 2007/12
N2 - An inexpensive and technically less-demanding methodology to quantify HIV-1 viral load would be of great value for resource-limited settings, where the nucleic-acid amplification technique (NAAT) is impractical and/or resource-prohibitive. In this study, an HIV-1 reverse-transcriptase enzyme-activity assay (ExaVir Load assay, version 1) was compared with the gold standard RT-PCR assay, Roche HIV-1 Amplicor Monitor, version 1.5. A total of 121 plasma specimens were used for the evaluation. ExaVir Load had a sensitivity of 97 % and a specificity of 71 % in identifying specimens with <400 copies ml-1 in the Roche RT-PCR assay as being less than the detection limit of the assay (5500 copies ml-1). The mean difference (95% limits of agreement) between Roche RT-PCR and ExaVir Load was -0.23 (-1.59 to 1.13) log10(copies ml-1) by Bland-Altman analysis. Significant negative correlations were seen between CD4+ T-cell counts and the ExaVir Load assay (r=-0.32, P<0.05), and between CD4+ T-cell counts and the Roche RT-PCR (r=-0.38, P<0.01). The present study with HIV-1 showed a strong correlation between the ExaVir Load assay and the RT-PCR assay. Hence, the ExaVir Load assay could be considered for use in resource-limited settings as an alternative viral-load assay to the standard NAAT-based assay after further evaluation with prospective specimens.
AB - An inexpensive and technically less-demanding methodology to quantify HIV-1 viral load would be of great value for resource-limited settings, where the nucleic-acid amplification technique (NAAT) is impractical and/or resource-prohibitive. In this study, an HIV-1 reverse-transcriptase enzyme-activity assay (ExaVir Load assay, version 1) was compared with the gold standard RT-PCR assay, Roche HIV-1 Amplicor Monitor, version 1.5. A total of 121 plasma specimens were used for the evaluation. ExaVir Load had a sensitivity of 97 % and a specificity of 71 % in identifying specimens with <400 copies ml-1 in the Roche RT-PCR assay as being less than the detection limit of the assay (5500 copies ml-1). The mean difference (95% limits of agreement) between Roche RT-PCR and ExaVir Load was -0.23 (-1.59 to 1.13) log10(copies ml-1) by Bland-Altman analysis. Significant negative correlations were seen between CD4+ T-cell counts and the ExaVir Load assay (r=-0.32, P<0.05), and between CD4+ T-cell counts and the Roche RT-PCR (r=-0.38, P<0.01). The present study with HIV-1 showed a strong correlation between the ExaVir Load assay and the RT-PCR assay. Hence, the ExaVir Load assay could be considered for use in resource-limited settings as an alternative viral-load assay to the standard NAAT-based assay after further evaluation with prospective specimens.
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U2 - 10.1099/jmm.0.47456-0
DO - 10.1099/jmm.0.47456-0
M3 - Article
C2 - 18033828
AN - SCOPUS:37249066240
SN - 0022-2615
VL - 56
SP - 1611
EP - 1614
JO - Journal of Medical Microbiology
JF - Journal of Medical Microbiology
IS - 12
ER -