Evaluation of LIAISON® XL system for HBsAg, and anti‐HCV and anti‐HIV/Ag p24

Abstract

The aim of this study was to compare the data obtained using the new LIAISON® XL chemiluminescence system to search for HBsAg, anti-HCV, and anti-HIV1-2/p24 Ag with those obtained using the VITROS system currently adopted by the Microbiology Unit of the Hospital of Legnano. Routine samples of patients who were referred by practitioners for the determination of HBsAg (1,000 samples) and/or anti-HCV (1,002 samples) and/or anti-HIV1-2 (995 samples) were simultaneously analyzed using both systems. The concordant positive and discordant samples were re-examined for confirmation by means of an HBsAg neutralization assay, anti-HCV immunoblot, or anti-HIV1-2 Western blot; HBV-DNA, or HCV-RNA or HIV-RNA was also sought in the discordant samples. Samples of patients known to be positive were tested (100 HBsAg positive, 100 anti-HCV positive, and 100 HIV 1-2 positive) as well throughout treatment, with viremia levels becoming undetectable after treatment. The HBsAg, anti-HCV, and anti-HIV1-2 concordance between the two systems in routine series was respectively 99.8%, 98.5% and 99.7%, and 100% for all markers in samples known positive. The various molecular biology and confirmatory tests of the discordant samples were all negative (except for one anti-HCV positive sample). Measure of Cohen's kappa coefficient for HBsAg, anti-HCV, and anti-HIV gave K values of respectively 0.992, 0.946, and 0.980. In conclusion, the performance of the LIAISON® XL system in the routine laboratory determination for all three markers was comparable with that of the VITROS system. J. Med. Virol. 89:489-496, 2017. © 2016 Wiley Periodicals, Inc.

Occult HBV Infection in Pregnant Women in Northern Benin

“…It is not known why the eradication is not complete, but it has been hypothesised that the occurrence of mutants in the S region may explain the persistence of viremia, although it has also been reported that more than half of the subjects without apparent mutations in the S gene have OBIs [36]. We re-tested our HBV DNA-positive and HBsAg-negative samples using a different test from that used in the previous study that is capable of detecting the most frequent mutants of HBV [42] because it has been suggested that HBsAg should be tested in this way [2]. With this test all samples were negative according to OBIs are characterised by undetectable HBV DNA and non-mutated HBsAg levels [11].…”

Threshold value of LIAISON XL anti‐HCV screening assay predicting positive immunoblotting results

“…As new immunoassay or chemiluminescence screening tests from companies such as Ortho, Abbott and Bayer come onto the market, the tables of threshold values (such as the S/CO ratio) have been updated using the values for each, but there are no indications concerning the recently available chemiluminescence test of DiaSorin. The performance of this system in detecting infectious disease has been previously tested, but not for this specific purpose. The aim of this study was to determine a threshold value for the DiaSorin LIAISON XL anti‐HCV test above which at least 95% of the samples are positive to an additional antibody test.…”