title: Comparison of three current viral load assays for the quantitation of human immunodeficiency virus type 1 RNA in plasma.
abstract: The LCx HIV RNA quantitative assay (Abbott Laboratories, Delkenheim, Germany) was compared with the Versant HIV-1 RNA 3.0 (bDNA) assay (Bayer, Tarrytown, NY) and the COBAS Amplicor HIV-1 Monitor v1.5 test (Roche Diagnostics, Branchburg, NJ), using plasma samples of various viral load levels from HIV-1-infected patients. Considering the lower limit of the linear range of 50 copies/ml of both assays, the detection range of the LCx was 127/151 (84.1%) versus the 131/151 (86.8%) of the bDNA 3.0 assay, while overall agreement between the two assays was 93.4% (141/151). LCx and bDNA 3.0 results were found to be strongly correlated (r = 0.96). The fitted regression line was described by the equation log10(LCx copies/ml) = 0.05 + 1.06 x log10(bDNA 3.0 copies/ml) with 95% CI for the estimated slope and intercept at 1.01, 1.12 and -0.16, 0.26, respectively. Similarly, the detection range of the LCx was 115/148 (77.7%) versus the 128/148 (86.5%) of the Monitor v1.5 test. A 91.2% concordance (135/148) was observed between these two assays at a cut-off of 50 copies/ml. LCx and Monitor v1.5 results were highly correlated (r = 0.96). The fitted regression line was described by the equation log10(LCx copies/ml) = 0.06 + 1.03 x log(10)(Monitor v1.5 copies/ml) with 95% CI for the estimated slope and intercept at 0.97, 1.09 and -0.16, 0.28, respectively.
authors.affiliation: Department of Hygiene and Epidemiology, Athens University Medical School, 75 Mikras Asias Street, GR-115 27 Athens, Goudi, Greece. ahatzak@med.uoa.gr
authors.forename: Antigoni
authors.initials: A
authors.lastname: Katsoulidou
authors.forename: Eleni
authors.initials: E
authors.lastname: Papachristou
authors.forename: Maria
authors.initials: M
authors.lastname: Petrodaskalaki
authors.forename: Vana
authors.initials: V
authors.lastname: Sypsa
authors.forename: Cleo G
authors.initials: CG
authors.lastname: Anastassopoulou
authors.forename: Panagiotis
authors.initials: P
authors.lastname: Gargalianos
authors.forename: Anastasia
authors.initials: A
authors.lastname: Karafoulidou
authors.forename: Marios
authors.initials: M
authors.lastname: Lazanas
authors.forename: Theodoros
authors.initials: T
authors.lastname: Kordossis
authors.forename: Anastasia
authors.initials: A
authors.lastname: Andoniadou
authors.forename: Angelos
authors.initials: A
authors.lastname: Hatzakis
mesh_terms: D015497:HIV-1 / Q000302:isolation & purification*; D006801:Humans; D025202:Molecular Diagnostic Techniques / Q000379:methods; D012367:RNA, Viral / Q000097:blood*; D011933:Reagent Kits, Diagnostic; D012044:Regression Analysis; D012680:Sensitivity and Specificity; D019562:Viral Load
chemical_list: D012367:RNA, Viral; D011933:Reagent Kits, Diagnostic