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Background: Hepatitis C virus (HCV) genotyping is required for tailoring the dose and duration of antiviral therapy, predicting virological response rates, and selecting future treatment options., Objective: To establish whether baseline genotypes, performed by INNO-LiPA Version 1.0 (v1.0), before 2008, were valid for making treatment decisions now or whether genotypic determination should be repeated. Furthermore, to evaluate concordance between Abbott RealTime genotype II assay (RT) and genotyping by sequencing HCV C/E1, NS5A, NS5B., Study Design: Genotyping by RT and sequencing was performed on paired historic and current specimens from 50 patients previously baseline genotyped using INNO-LiPA., Results: Of 100 samples from 50 patients, ≥ 2 of HCV genomic target regions yielded a sequence that was suitable for genotyping, with 100% concordance, providing no evidence of recombination events. Genotype and subtype prediction based on RT and sequencing agreed in 62.8% historic and 72.7% current specimens, with a kappa coefficient score of 0.48 and 0.76, respectively. LiPA could not subtype 46% of HCV gt1 infections, and LiPA subgenotype was only in agreement with RT and sequencing in 28.6% cases, where matched baseline and historic specimens were available. Three patients were indeterminate by RT, and five patients with HCV gt1 infections could not be subtyped by RT. However, RT revealed mixed infections in five patients where sequencing detected only single HCV infection at 20% threshold., Conclusion: Genotyping by sequencing, exhibited excellent concordance, with moderate to good agreement with RT, and could resolve RT indeterminates and subtype HCV-gt1 infections not possible by LiPA., (Copyright © 2015 Elsevier B.V. All rights reserved.)

Background: The quantitative measurement of HIV-1 RNA levels in plasma ('viral load') is essential in the management of HIV-infected patients., Objective: The new Artus HIV-1 QS-RGQ assay ('Artus(HIV)') for HIV-1 RNA quantification in plasma was compared to the Abbott RealTime HIV-1 assay ('RealTime') following automated RNA isolation by the QIAsymphony and Abbott m2000 extractors, respectively. Emphasis was placed on assay performance with diverse HIV-1 subtypes and in patients receiving antiretroviral therapy (ART)., Study Design: Plasma from 211 patients (105 subtype B, 87 non-B subtypes; 147 on ART) and serial dilutions of the WHO 2nd International HIV-1 RNA Standard (WHO-IS) were tested by the two assays in parallel. Assay relationship and agreement were determined by linear regression, correlation analysis, and Bland-Altman analysis., Results: With 125 specimens quantified by both assays, measurements were linearly associated and strongly correlated. Overall Artus reported higher levels by mean 0.24 (95% confidence interval [CI] 0.16-0.32) log(10) copies/ml (P < 0.0001); 5 samples (subtypes A, B, CRF01, CRF03) fell outside the 95% agreement. Discordant results were obtained with 11 and 13 samples quantified by either ArtusHIV or RealTime alone respectively, at levels generally close to the lower limit of quantification, giving an overall discordance rate of 24/211 (11%). Both assays generally under-quantified the WHO-IS by between 0.1 and 0.4 log(10) copies/ml across seven dilutions., Conclusions: The ArtusHIV assay offers performance comparable to that of the RealTime assay across a wide range of HIV-1 subtypes and among both treated and untreated patients., (Copyright © 2013 Elsevier B.V. All rights reserved.)