BACKGROUND: Plasma human immunodeficiency virus type 1 (HIV-1) RNA level is an important parameter for patient management, yet viral load assays from different manufacturers are not standardized. OBJECTIVES AND STUDY DESIGN: In this study, we evaluated the concordance between test results obtained for 1,000 plasma specimens collected from HIV-1-infected individuals measured with the VERSANT HIV-1 RNA 3.0 assay (bDNA) and the COBAS AMPLICOR HIV-1 MONITOR 1.5 test (PCR). We compared viral load values obtained by each of these assays throughout their dynamic ranges, with particular focus on samples with low viral load (i.e. 50-250 copies/mL), and calculated the estimated distribution of distinct plasma viral load levels for the entire study population modeled from the data observed in the study. RESULTS: We found that these two assays show excellent agreement, with a correlation (R(2)) of 0.957 and a slope of 1.004. The mean difference in viral load values between the two assays was less than 0.10-log(10) throughout the dynamic range and 98.2% of all samples had bDNA and PCR results within 0.5-log(10) of each other, a difference that is within the range considered to be a minimal change in plasma viremia. Moreover, the two assays show very similar results across all assay ranges tested. The estimated prevalence of samples with results <50 copies/mL, 50-250 copies/mL, and 250-500,000 copies/mL were 41.6%, 7.7%, and 49.7%, respectively, by the bDNA assay, and 42.4%, 6.9%, and 50.7%, respectively, by the PCR assay. CONCLUSION: Based on our findings from 1,000 clinical specimens, we do not see the need to re-establish a baseline value or apply a conversion factor when switching from one assay to the other. Since the majority of our patient population likely is infected with subtype B virus, it is unclear if our findings will apply to other patient populations with a greater incidence of infection with non-B subtypes.
BACKGROUND: Plasma human immunodeficiency virus type 1 (HIV-1) RNA level is an important parameter for patient management, yet viral load assays from different manufacturers are not standardized. OBJECTIVES AND STUDY DESIGN: In this study, we evaluated the concordance between test results obtained for 1,000 plasma specimens collected from HIV-1-infected individuals measured with the VERSANT HIV-1 RNA 3.0 assay (bDNA) and the COBAS AMPLICOR HIV-1 MONITOR 1.5 test (PCR). We compared viral load values obtained by each of these assays throughout their dynamic ranges, with particular focus on samples with low viral load (i.e. 50-250 copies/mL), and calculated the estimated distribution of distinct plasma viral load levels for the entire study population modeled from the data observed in the study. RESULTS: We found that these two assays show excellent agreement, with a correlation (R(2)) of 0.957 and a slope of 1.004. The mean difference in viral load values between the two assays was less than 0.10-log(10) throughout the dynamic range and 98.2% of all samples had bDNA and PCR results within 0.5-log(10) of each other, a difference that is within the range considered to be a minimal change in plasma viremia. Moreover, the two assays show very similar results across all assay ranges tested. The estimated prevalence of samples with results <50 copies/mL, 50-250 copies/mL, and 250-500,000 copies/mL were 41.6%, 7.7%, and 49.7%, respectively, by the bDNA assay, and 42.4%, 6.9%, and 50.7%, respectively, by the PCR assay. CONCLUSION: Based on our findings from 1,000 clinical specimens, we do not see the need to re-establish a baseline value or apply a conversion factor when switching from one assay to the other. Since the majority of our patient population likely is infected with subtype B virus, it is unclear if our findings will apply to other patient populations with a greater incidence of infection with non-B subtypes.
Authors: Pablo S Rivadeneira; Claude H Moog; Guy-Bart Stan; Cecile Brunet; François Raffi; Virginie Ferré; Vicente Costanza; Marie J Mhawej; Federico Biafore; Djomangan A Ouattara; Damien Ernst; Raphael Fonteneau; Xiaohua Xia Journal: Biores Open Access Date: 2014-10-01
Authors: C Thomas Nugent; Vladislav Nodelman; Cristina Giachetti; Douglas D Richman; David J Looney Journal: J Clin Microbiol Date: 2008-12-30 Impact factor: 5.948
Authors: Jane Greig; Philipp du Cros; Derryck Klarkowski; Clair Mills; Steffen Jørgensen; P Richard Harrigan; Daniel P O'Brien Journal: J Int AIDS Soc Date: 2011-05-12 Impact factor: 5.396
Authors: Luuk Gras; Suzanne Jurriaans; Margreet Bakker; Ard van Sighem; Daniela Bezemer; Christophe Fraser; Joep Lange; Jan M Prins; Ben Berkhout; Frank de Wolf Journal: PLoS One Date: 2009-10-07 Impact factor: 3.240
Authors: Philip A Chan; Sarah E Wakeman; Timothy Flanigan; Susan Cu-Uvin; Erna Kojic; Rami Kantor Journal: AIDS Res Ther Date: 2008-08-14 Impact factor: 2.250
Authors: W Stevens; G Sherman; R Downing; L M Parsons; C-Y Ou; S Crowley; G M Gershy-Damet; K Fransen; M Bulterys; L Lu; J Homsy; T Finkbeiner; J N Nkengasong Journal: Open AIDS J Date: 2008-03-10
Authors: Kimberly A Sollis; Pieter W Smit; Susan Fiscus; Nathan Ford; Marco Vitoria; Shaffiq Essajee; David Barnett; Ben Cheng; Suzanne M Crowe; Thomas Denny; Alan Landay; Wendy Stevens; Vincent Habiyambere; Jos Perrins; Rosanna W Peeling Journal: PLoS One Date: 2014-02-18 Impact factor: 3.240