Multicenter clinical comparative evaluation of Alinity m HIV-1 assay performance.

Abstract Background Accurate, rapid detection of HIV-1 RNA is critical for early diagnosis, treatment decision making, and long-term management of HIV-1 infection. Objective We evaluated the diagnostic performance of the Alinity m HIV-1 assay, which uses a dual target/dual probe design against highly conserved target regions of the HIV-1 genome and is run on the fully automated Alinity m platform. Study design This was an international, multisite study that compared the diagnostic performance of the Alinity m HIV-1 assay to four commercially available HIV-1 assays routinely used in nine independent clinical laboratories. Alinity m HIV-1 assay precision, detectability, and reproducibility was compared across four study sites. Results The Alinity m HIV-1 assay produced comparable results to currently available HIV-1 assays (correlation coefficient >0.995), with an overall bias of -0.1 to 0.10 Log10 copies/mL. The Alinity m HIV-1 assay and its predecessor m2000 HIV-1 assay demonstrated comparable detection of 16 different HIV-1 subtypes (R2 = 0.956). A high level of agreement (>88 %) between all HIV-1 assays was seen near clinical decision points of 1.7 Log10 copies/mL (50 copies/mL) and 2.0 Log10 copies/mL (200 copies/mL). Alinity m HIV-1 assay precision was 0.08 and 0.21 Log10 copies/mL at VLs of 1000 and 50 copies/mL, respectively, with a high level of detectability (≥97 % hit rate) and reproducibility across sites. Conclusions The Alinity m HIV-1 assay provides comparable diagnostic accuracy to current HIV-1 assays, and when run on the Alinity m system, has the capacity to shorten the time between diagnosis and treatment

A Higher Correlation of HCV Core Antigen with CD4+ T Cell Counts Compared with HCV RNA in HCV/HIV-1 Coinfected Patients

Development of HCV infection is typically followed by chronic hepatitis C (CHC) in most patients, while spontaneous HCV viral clearance (SVC) occurs in only a minority of subjects. Compared with the widespread application of HCV RNA testing by quantitative RT-PCR technique, HCV core antigen detection may be an alternative indicator in the diagnosis of hepatitis C virus infections and in monitoring the status of infectious individuals. However, the correlation and differences between these two indicators in HCV infection need more investigation, especially in patients coinfected by HIV-1. In this study, a total of 354 anti-HCV and/or anti-HIV serum positive residents from a village of central China were enrolled. Besides HCV-related hepatopathic variables including clinical status, ALT, AST, anti-HCV Abs, as well as the altered CD4+/CD8+ T cell counts, HCV core antigen and HCV viral load were also measured. The concentration of serum HCV core antigen was highly correlated with level of HCV RNA in CHC patients with or without HIV-1 coinfection. Of note, HCV core antigen concentration was negatively correlated with CD4+ T cell count, while no correlation was found between HCV RNA level and CD4+ T cell count. Our findings suggested that quantitative detection of plasma HCV core antigen may be an alternative indicator of HCV RNA qPCR assay when evaluating the association between HCV replication and host immune status in HCV/HIV-1 coinfected patients

Antiretroviral-naive and -treated HIV-1 patients can harbour more resistant viruses in CSF than in plasma

Objectives The neurological disorders in HIV-1-infected patients remain prevalent. The HIV-1 resistance in plasma and CSF was compared in patients with neurological disorders in a multicentre study. Methods Blood and CSF samples were collected at time of neurological disorders for 244 patients. The viral loads were >50 copies/mL in both compartments and bulk genotypic tests were realized. Results On 244 patients, 89 and 155 were antiretroviral (ARV) naive and ARV treated, respectively. In ARV-naive patients, detection of mutations in CSF and not in plasma were reported for the reverse transcriptase (RT) gene in 2/89 patients (2.2%) and for the protease gene in 1/89 patients (1.1%). In ARV-treated patients, 19/152 (12.5%) patients had HIV-1 mutations only in the CSF for the RT gene and 30/151 (19.8%) for the protease gene. Two mutations appeared statistically more prevalent in the CSF than in plasma: M41L (P = 0.0455) and T215Y (P = 0.0455). Conclusions In most cases, resistance mutations were present and similar in both studied compartments. However, in 3.4% of ARV-naive and 8.8% of ARV-treated patients, the virus was more resistant in CSF than in plasma. These results support the need for genotypic resistance testing when lumbar puncture is performe

Multicenter Performance Evaluation of a New TaqMan PCR Assay for Monitoring Human Immunodeficiency Virus RNA Load

A TaqMan real-time PCR assay, the COBAS TaqMan human immunodeficiency virus (HIV) (HPS-CTMHIV) PCR assay, recently developed for the quantification of HIV type 1 RNA in plasma, was evaluated in comparison with the licensed COBAS AMPLICOR HIV-1 MONITOR (CAHIM) assay. In this study, we have analyzed the tests' sensitivities, precisions, and linearities using multiple replicates of a standard panel of HIV RNA covering a 7-logarithm range of concentrations, as well as serial threefold dilutions of high-titer clinical samples. The subtype inclusivity was also investigated, using a panel of subtypes A to H, while a collection of 160 clinical samples was analyzed to assess the tests' specificities and the systems' similarities. The results of these experiments showed that the HPS-CTMHIV assay has a sensitivity of 53 copies/ml (95% hit rate), 100% specificity, and good intra- and interassay precision. The results of the HPS-CTMHIV assay were linear in the 50- to 10(7)-copies/ml range, with a correlation coefficient (R) for expected versus observed results of 0.98. Compared to the CAHIM assay, the HPS-CTMHIV assay showed a high correlation (R = 0.99) across the dynamic range of RNA concentrations that, for the CAHIM assay, requires two different sample preparations. Equivalent performances were also observed for the two systems in the detection and quantification of HIV subtypes A to H. These data indicate that the HPS-CTMHIV assay may be one of the tests of choice for monitoring viral load throughout the course of HIV infection and during highly active antiretroviral therapy

Hepatitis C subtype distribution in chronically infected patients with mild liver fibrosis in France: the GEMHEP study

International audienc

Comparison of a Newly Developed Automated and Quantitative Hepatitis C Virus (HCV) Core Antigen Test with the HCV RNA Assay for Clinical Usefulness in Confirming Anti-HCV Results ▿

Hepatitis C virus (HCV) is a global health care problem. Diagnosis of HCV infection is mainly based on the detection of anti-HCV antibodies as a screening test with serum samples. Recombinant immunoblot assays are used as supplemental tests and for the final detection and quantification of HCV RNA in confirmatory tests. In this study, we aimed to compare the HCV core antigen test with the HCV RNA assay for confirming anti-HCV results to determine whether the HCV core antigen test may be used as an alternative confirmatory test to the HCV RNA test and to assess the diagnostic values of the total HCV core antigen test by determining the diagnostic specificity and sensitivity rates compared with the HCV RNA test. Sera from a total of 212 treatment-naive patients were analyzed for anti-HCV and HCV core antigen both with the Abbott Architect test and with the molecular HCV RNA assay consisting of a reverse transcription-PCR method as a confirmatory test. The diagnostic sensitivity, specificity, and positive and negative predictive values of the HCV core antigen assay compared to the HCV RNA test were 96.3%, 100%, 100%, and 89.7%, respectively. The levels of HCV core antigen showed a good correlation with those from the HCV RNA quantification (r = 0.907). In conclusion, the Architect HCV antigen assay is highly specific, sensitive, reliable, easy to perform, reproducible, cost-effective, and applicable as a screening, supplemental, and preconfirmatory test for anti-HCV assays used in laboratory procedures for the diagnosis of hepatitis C virus infection

O112 : HBsAg clearance after addition of 48 weeks of pegifn in HBeAg negative CHB patients on nucleos(T)ide therapy with undetectable hbvdna for at least one year: final results from ANRS-HB06 pegan study: multicenter randomized controlled phase III trial

International audienceno abstrac