Multicenter clinical evaluation of the new 3rd generation assay for detection of antibodies against hepatitis C virus on the VIDAS(®) system

Evaluation of the bioMérieux VIDAS HIV Duo Quick and Anti-HCV assays for dried blood spot based serosurveillance

Serosurveillance is central to monitoring our progress towards HIV and HCV elimination targets proposed for 2030. However, serosurveillance systems are ineffective without reliable serological assays for the detection of HIV and HCV antibodies. Assays should also be compatible with dried blood spot (DBS) samples to facilitate biological sample collection. The VIDAS HIV Duo Quick and Anti-HCV assays are sold as reagents strips and processed by the automated VIDAS benchtop immunoanalyser. While both assays have shown excellent performance in serum and plasma, performance data in DBS samples is lacking. In our study, we evaluate the performance of the VIDAS HIV Duo Quick and Anti-HCV assays in DBS (n = 725) collected during a cross-sectional serosurvey (the Transitions study). The VIDAS HIV Duo quick had a sensitivity and specificity of 94.5% (95% CI 85.1%, 98.5%) and 95.7% (95% CI 93.9%, 97.0%) respectively. Likewise, the VIDAS Anti-HCV had a sensitivity and specificity of 95.6% (95% CI 91.6%, 97.8%) and 95.6% (95% CI 93.5%, 97.0%) respectively. These assays are unlikely to be helpful in low-prevalence settings due to sub-optimal performance, but their performance could likely be improved by optimizing DBS elution protocols which was, unfortunately, not possible during our study.

Metaanálisis de la validez y el desempeño de las pruebas de tamización del virus de la hepatitis C en bancos de sangre, 2000-2018

Este estudio evaluó la validez y desempeño del inmunodiagnóstico del virus de la hepatitis C (VHC), con base en estudios publicados en la literatura científica mundial. Se diseñó y validó un protocolo de búsqueda y selección de investigaciones en las fases de la guía PRISMA, se analizaron los parámetros de sensibilidad, especificidad, cocientes de probabilidad, razón de odds y curva ROC, en MetaDisc. Se tamizaron 4602 estudios, de los cuales sólo 545 se realizaron en bancos de sangre y 18 evaluaron la validez diagnóstica de las pruebas para el VHC. La mayoría de los estudios fueron de Europa y Asia, con un 78 % basados en determinación de anticuerpos. Los estudios con detección de anticuerpos se realizaron en 21 483 donantes sanos y 3 145 infectados en quienes se halló una sensibilidad de 97,8 % (IC 95 % = 97,3 - 98,2), especificidad 99,0 % (IC 95 % = 98,9 - 99,2), cociente de probabilidad positivo 75,4 (IC 95 % = 27,2 - 209,2) y negativo de 0,02 (IC 95 % = 0,01 - 0,07) y área bajo la curva de 99,8 %. Se concluye que la detección de anticuerpos presenta excelente validez, desempeño y utilidad diagnóstica para la detección del VHC en donantes de sangre y población general.

Comparison of 2 different antibody assay methods, Elecsys Anti-HCVII (Roche) and Vidas Anti-HCV (Biomerieux), for the detection of antibody to hepatitis C virus in Egypt

The measurement of antibodies against hepatitis C virus (HCV) is important to screen HCV infection. The aim of this study is to investigate the reliability of 2 commercially available anti-HCV antibody kits used in routine laboratory testing in Egypt. One thousand nine hundred and thirty-one serum samples were analyzed using 2 anti-HCV test systems: Cobas e 411® Elecsys Anti-HCVII and Vidas® Anti-HCV Biomerieux. Discrepant samples were tested using the recombinant immunoblot assay Innogenetics® INNO-LIA HCV Score. Overall agreement of the 2 tests was 94%. Following discrepant sample testing by LIA, sensitivity and specificity using Vidas were 94% and 99%, respectively, while those for Cobas were 97% and 96%, respectively. This study demonstrates superior specificity by Vidas and higher sensitivity by Cobas. Both methods are suitable for laboratory and/or blood screening programs. The concomitant use of a supplementary or confirmatory assay is necessary to compare the accuracy of HCV serological assays.

Budget impact analysis on the introduction of a guideline based hepatitis B and C screening into a routine check-up in the German primary care setting

OBJECTIVES

Systematic screening for chronic hepatitis B and C does not yet exist in Germany. Therefore, the implementation of a screening approach within a preventive medical examination performed by primary care physicians ('Check-Up 35+') was evaluated in a recent prospective multicenter study. The present analysis estimates the financial consequences for the statutory health insurance by budget impact analysis.

MATERIALS AND METHODS

A Markov cohort model was developed consisting of 21 health states. Four different screening scenarios derived from the previous multicenter study were compared to usual care, a strategy without screening for hepatitis. Actual cost data for Germany were calculated and systematic literature searches for all input parameters were performed.

RESULTS

The base case results in incremental costs for the screening strategies compared to no hepatitis screening of 165-227 € per patient in a 20-year horizon. Two main parameters influence the financial consequences: (A) detection and treatment increase the costs in the beginning. (B) Screening avoids hepatitis induced end-stage liver disease. The initial higher costs exceed the later savings. Sensitivity analyses demonstrate a strong impact of medication costs for the treatment of additionally detected hepatitis infections on the outcome. This finding is robust to sensitivity analysis.

CONCLUSIONS

The screening strategy proposed here implies additional costs for the statutory health insurance, however, a decision regarding its usefulness must consider criteria other than cost. For example, the high burden of disease due to liver cirrhosis and liver carcinoma should be considered. Therefore, an additional cost-effectiveness-analysis should be conducted.

The serological markers of acute infection with hepatitis A, B, C, D, E and G viruses revisited

Viral hepatitis is a liver infection caused by one of the six hepatitis viruses: hepatitis A, B, C, D, E, and G virus (HAV to HEV and HGV). These agents differ in their biological, immunological, pathological and epidemiological characteristics. They cause infections that, when symptomatic, lead to clinical manifestations and laboratory findings that are not specific to a particular virus, often making differential diagnosis difficult, especially when no knowledge is available regarding the patient's medical history or the epidemiological background. A number of acute-phase serological markers, such as anti-HAV, anti-HBc, anti-HDV and anti-HEV IgM antibodies, are able to provide a clear indication of an infection caused by HAV, HBV, HDV or HEV. Anti-HCV antibodies and HGV/RNA are used for the diagnosis of HCV and HGV infections. The importance of each of these markers will be reviewed, and different factors that can interfere with the diagnosis of acute infections caused by these viruses will be described.

Evaluation of the VIDAS Anti-HCV Assay for Detection of Hepatitis C Virus Infection

BACKGROUND

Anti-hepatitis C virus antibody (anti-HCV) assays are recommended for screening HCV-infected persons. The VIDAS Anti-HCV Assay (bioMérieux, France), based on the enzyme-linked fluorescence test principle, was recently introduced in Korea. We evaluated the clinical performance of the VIDAS assay.

METHODS

One hundred HCV-positive and 1,002 HCV-negative blood samples confirmed by Architect anti-HCV (Abbott Laboratories, USA) and COBAS TaqMan HCV real-time PCR (Roche Diagnostics, USA) or the Procleix Ultrio Plus Assay (Gen-Probe Incorporated, USA) were obtained from the Human Serum Bank (HSB) and tested by VIDAS. In case of discrepant results, we conducted a recombinant immunoblot assay (RIBA).

RESULTS

The agreement rates for known HCV-positive and HCV-negative samples between the VIDAS assay and the HSB testing were 100% (95% confidence interval [CI]: 96.4-100%) and 99.5% (95% CI: 98.8-99.8%), respectively. One of the five discrepant samples was positive for Core 2+ and NS3-2 2+ reactivity, two samples were negative, and the other two were indeterminate regarding NS4 2+ reactivity in RIBA. We observed a significant but weak positive correlation between the titers of VIDAS and Architect assays (r=0.315, P<0.001).

CONCLUSIONS

The VIDAS anti-HCV assay, developed on the VIDAS automated immunoassay platform based on the ready-to-use, single-sample test concept may be useful in small-to-medium-sized laboratories. It showed good agreement with Architect anti-HCV and COBAS PCR assays and is therefore useful for detection of HCV infection. Weakly test-positive (ambiguous) samples require additional testing by another anti-HCV, RIBA, or HCV RNA assay.