Multicenter evaluation of the elecsys® anti-HCV II assay for the diagnosis of hepatitis C virus infection

Comparison of a dual antibody and antigen HCV immunoassay to standard of care algorithmic testing

The Centers for Disease Control and Prevention (CDC) guidelines for hepatitis C virus (HCV) testing, although effective, may miss crucial diagnostic opportunities. The goal of this study was to assess the utility of an antibody (Ab) and antigen (Ag) combination immunoassay as an alternative to traditional HCV screening. Remnant specimens from 1,341 patients with concurrent third-generation serologic (Roche anti-HCV-II) and nucleic acid amplification testing (NAAT) were assessed using the HCV Duo Ab/Ag immunoassay (Roche). Patient demographics, risk factors, and standard of care (SOC) laboratory results from the medical records were recorded. Overall, 99.0% (197/199) of the HCV Duo Ab+/Ag+specimens accurately identified active infections as confirmed by NAAT, and 99.9% (670/671) Ab-/Ag- samples corresponded to those without HCV infections. Individually, the HCV Duo Ab component demonstrated a 95.6% positive percent agreement (PPA) (95% CI = 93.8-96.9) and 99.1% negative percent agreement (NPA) (98.8-99.6) compared with SOC anti-HCV II Ab assay. The HCV Duo Ag had a 73.5% PPA (67.9-78.4) and 99.8% NPA (99.3-100) with NAAT. Among RNA+ specimens, 73.4% (197/267) were HCV Duo Ag+, and 265/267 (99.3%) were successfully detected on the HCV Duo Ab component. Notably, 5/7 (71.4%) Ab-/RNA +specimens were detected by HCV Duo, which would have been missed by traditional algorithmic testing. Fourth generation HCV Duo Ab/Ag assay demonstrated comparable performance to SOC testing and shortens the diagnostic window but does not eliminate the need for NAAT in all patients. Ab/Ag testing identified several Ab-/RNA+ cases, a subgroup often undiagnosed by current algorithmic testing, demonstrating promise for improved diagnostic efficiency and accuracy in HCV detection.IMPORTANCEThis study highlights the potential of a combined hepatitis C virus (HCV) Duo antibody (Ab) and antigen (Ag) immunoassay to improve early detection of HCV infections. Traditional Ab-only screening methods recommended by the Centers for Disease Control and Prevention may miss early-stage infections. The HCV Duo assay showed high accuracy, detecting nearly all active infections confirmed by nucleic acid amplification testing. Dual detection of HCV Ab and Ag shortens the diagnostic window, enabling intervention and treatment in a single visit, which is crucial for improving patient outcomes and reducing HCV transmission, especially in areas with limited access to confirmatory molecular testing.

Prevalence of Transfusion-Transmitted Infections (HCV, HIV, Syphilis and Malaria) in Blood Donors: A Large-Scale Cross-Sectional Study

Blood plays a major role in transmitting infectious diseases such as hepatitis C virus (HCV), human immunodeficiency virus (HIV), hepatitis B virus (HBV), syphilis, malaria, and many others. Thus, this study sought to evaluate the distribution of HCV, HIV, syphilis, and malaria among blood donors in Yemen. This is a cross-sectional study, conducted on blood donors at the national center in Yemen. Blood donors’ specimens were serologically tested for the presence of anti-HCV and anti-HIV antibodies, as well as anti-Treponema pallidum, anti-Plasmodium falciparum, and anti-Plasmodium vivax. A total of 16,367 donors were included in this study. Based on the donor’s occupation, the study showed that the relative seroprevalence of anti-HCV Ab among the donors was statistically significant, and relatively high prevalence was found among military donors (2.8%). Positive HIV antibody tests were only reported in 33 male donors (0.2%), who were mostly manual workers. A remarkably high prevalence of anti-Treponema pallidum was observed among manual workers (3.1%). There was a statistically significant difference in the distribution of anti-malaria Ab based on residency and age groups. This study revealed that the prevalence of HCV, HIV, syphilis, and malaria among donors was 2.0%, 0.2%, 2.4%, and 0.7%, respectively. Further genotyping studies are necessary to provide a complete picture of the prevalence of transfusion-transmitted infections (TTIs).

Clinical performance evaluation of Elecsys HIV Duo, Anti-HCV II, HBsAg II, Anti-HBc II, and Syphilis assays for routine screening of first-time blood donor samples at a French blood donation center

OBJECTIVES

Implementing fully automated analyzers has become a crucial safety step in blood donation centers. The Elecsys® assays were evaluated on the cobas e 801 module (Roche Diagnostics) for routine first-time blood donor screening.

MATERIALS & METHODS

Five Elecsys infectious disease assays were tested on the cobas e 801 module at Etablissement Français du Sang, Montpellier, France (March-April 2018). The performance of Elecsys HIV Duo, Anti-HCV II, HBsAg II, Anti-HBc II, and Syphilis assays was compared with PRISM HIV O Plus, HCV, HBsAg, HBcore, and newbio pk TPHA assays (specificity analyses)/ARCHITECT Syphilis TP (sensitivity analyses), respectively. Specificity was determined in residual fresh serum samples from unselected first-time blood donors (n≥5195 per parameter). Elecsys assay sensitivity was tested using 30 preselected, positively characterized samples per assay and compared with archived routine testing data for comparator assays.

RESULTS

Across all parameters, specificities for repeatedly reactive samples ranged from 99.81-100.00% for Elecsys assays and 99.71-99.98% for comparator assays. Sensitivities of Elecsys and comparator assays were the same for hepatitis C (85.19%), hepatitis B surface antigen (70.00%), hepatitis B core antigen antibodies (100.00%), and syphilis (100.00%). The sensitivity of the Elecsys HIV Duo assay was higher than the comparator assay (83.33% vs. 76.67%), but the difference was not statistically significant.

CONCLUSIONS

Elecsys infectious disease assays on the cobas e 801 module demonstrated high specificity and sensitivity for screening first-time blood donor samples, and were comparable with other commercially available assays. The Elecsys assays are reliable tests for screening blood donations.

Drassanes Exprés: a public and confidential testing service for asymptomatic STIs with same-day result notification

BACKGROUND

STIs are a major public health concern. Screening programmes for asymptomatic users are key components of STI control. Traditional limitations of screening programmes include low population coverage and delays in treatments, thus reducing the expected impact on STI control. In our centre, the normal time from test to results was 4 days, and 7 days until treatment was established.To reduce time to treatment and to increase population coverage, we developed 'Drassanes Exprés', a testing service for asymptomatic STIs. The objectives of this study were to provide a guide for the implementation of a service with these characteristics and to evaluate the results of this intervention.

METHODS

The Drassanes Exprés programme was launched in Spain on 07 November 2016 as a public, confidential and free-of-charge testing service for asymptomatic STIs, with same-day result notification. For this walk-in service, confidentiality was obtained by registering all information into the Laboratory Internal Software instead of the Electronic Patient Records. Samples were processed in a point-of-care laboratory and result notification was provided via mail or short message service.Information about workflow, screening protocols and result interpretation is detailed. Additionally, demographic characteristics, STI prevalence, and time from patients' sample collection to notification and treatment are analysed.

RESULTS

Between 07 November 2016 and 07 November 2019, 13 993 users attended the Drassanes Exprés screening programme. Of these, 0.5% were transgender people, 29.3% women, 45.2% men who have sex with men and 25.1% men who have sex with women. The median age was 31 years (range: 26-39 years). Overall, 14.6% of users tested positive for at least one STI. The most prevalent infection was Chlamydia trachomatis (8.3%), followed by Neisseria gonorrhoeae (5.7%), syphilis (1.8%), HIV (0.4%) and hepatitis C virus (0.2%). The median time from test to results was 2.4 hours (range: 2-3.1 hours). Of 2049 users diagnosed with an STI, treatment was achieved in 97.0% of cases; the average time to treatment was 2.0 days.

CONCLUSIONS

Drassanes Exprés is the first public programme for rapid, asymptomatic, STI screening and treatment in Spain. Assessing high-risk practices and providing confidentiality, easy access and rapid results/treatments are key elements in the development of STI screening programmes.

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.

Clinical diagnostic performance of light-initiated chemiluminescent assay compared with the Architect chemiluminescence immunoassay for detection of HCV antibody

BACKGROUND

Hepatitis C virus antibody (anti-HCV) test had been approved as a preliminary screening test for HCV infection. Light-initiated chemiluminescent assay (LiCA) was a homogenous method. We aimed to assess the clinical diagnostic performance of LiCA and compare it with that of chemiluminescence immunoassay (CLIA) which was widely used in clinical laboratories.

METHODS

A total of 10 772 patients from the Peking University Third Hospital were enrolled. The serum samples were detected on the ChIVD LiCA500 and Abbott Architect i2000SR platforms. Recombinant immunoblot assay (RIBA) and HCV RNA assay were used for confirmation.

RESULTS

The negative agreement rate between ChIVD LiCA anti-HCV assay and Abbott Architect anti-HCV assay was 99.91%, the positive agreement rate was 37.31%, the total agreement rate was 98.74%, and the kappa coefficient (κ) was 0.519. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of ChIVD LiCA anti-HCV assay were 96.39%, 99.95%, 89.58%, and 99.97%, respectively, which were superior to those of Abbott Architect anti-HCV assay (93.98%, 99.25%, 51.90%, and 99.95%, respectively).

CONCLUSION

ChIVD LiCA anti-HCV assay was a highly sensitive, specific homogenous method with good diagnostic performance, and was applicable for the routine screening of HCV infection in clinical laboratories.

Differential reactivity of anti-hepatitis C virus screening assays in patients with waning antibodies

Hepatitis C virus (HCV) leads to persistent infection. Viral clearance can be obtained through pharmacological treatment or spontaneously. After viral clearance, anti-HCV antibodies (Abs) slowly decline and finally disappear. Subjects with a resolved HCV infection are reactive to anti-HCV screening assays for a long time. These subjects pose a diagnostic challenge, and therefore, a more accurate interpretation of laboratory tests is needed for cases with resolved HCV infection. However, the performances of anti-HCV screening assays against declining anti-HCV Abs have not been assessed. Here we evaluated 1509 samples with different screening assays. Screening assays provided discrepant results in patients with waning Abs. The identification of signal-to-cut-off values indicative of waning Abs for each anti-HCV assay could avoid unnecessary confirmatory tests and reduce the impact of misdiagnosis.

Development of a Rapid Automated Fluorescent Lateral Flow Immunoassay to Detect Hepatitis B Surface Antigen (HBsAg), Antibody to HBsAg, and Antibody to Hepatitis C

Background

Accurate, rapid, and cost-effective screening tests for hepatitis B virus (HBV) and hepatitis C virus (HCV) infection may be useful in laboratories that cannot afford automated chemiluminescent immunoassays (CLIAs). We evaluated the diagnostic performance of a novel rapid automated fluorescent lateral flow immunoassay (LFIA).

Methods

A fluorescent LFIA using a small bench-top fluorescence reader, Automated Fluorescent Immunoassay System (AFIAS; Boditech Med Inc., Chuncheon, Korea), was developed for qualitative detection of hepatitis B surface antigen (HBsAg), antibody to HBsAg (anti-HBs), and antibody to HCV (anti-HCV) within 20 minutes. We compared the diagnostic performance of AFIAS with that of automated CLIAs—Elecsys (Roche Diagnostics GmbH, Penzberg, Germany) and ARCHITECT (Abbott Laboratories, Abbott Park, IL, USA)—using 20 seroconversion panels and 3,500 clinical serum samples.

Results

Evaluation with the seroconversion panels demonstrated that AFIAS had adequate sensitivity for HBsAg and anti-HCV detection. From the clinical samples, AFIAS sensitivity and specificity were 99.8% and 99.3% for the HBsAg test, 100.0% and 100.0% for the anti-HBs test, and 98.8% and 99.1% for the anti-HCV test, respectively. Its agreement rates with the Elecsys HBsAg, anti-HBs, and anti-HCV detection assays were 99.4%, 100.0%, and 99.0%, respectively. AFIAS detected all samples with HBsAg genotypes A-F and H and anti-HCV genotypes 1, 1a, 1b, 2a, 2b, 4, and 6. Cross-reactivity with other infections was not observed.

Conclusions

The AFIAS HBsAg, anti-HBs, and anti-HCV tests demonstrated diagnostic performance equivalent to current automated CLIAs. AFIAS could be used for a large-scale HBV or HCV screening in low-resource laboratories or low-to middle-income areas.

Performance evaluation of the mindray anti-HCV assay for the detection of hepatitis C virus infection

BACKGROUND

Anti-hepatitis C virus (anti-HCV) antibody assays are recommended for HCV infection screening. The Mindray anti-HCV assay, based on a third-generation immunoassay, was recently launched in China. We aimed to evaluate its diagnostic performance compared with that of two other widely used assays.

METHODS

Six HCV infection seroconversion panels were used to evaluate the sensitivity of the assay for early detection. A total of 1952 clinical samples were tested by the Mindray anti-HCV, Elecsys anti-HCV II, and Architect anti-HCV assays. Samples with reactive results using at least one anti-HCV assay were further tested with the recombinant immunoblot assay (RIBA). Inconsistent results were investigated by the HCV RNA assay and HCV core antigen assay. HCV infection diagnosis was made according to the results of laboratory tests and medical records.

RESULTS

The Mindray anti-HCV assay and Elecsys anti-HCV II assay detected seroconversion in an average of 12.5 days and 10.5 days, respectively, and this difference was not significant (P = .818). Of the 1952 cases, 90 were categorized as "HCV infection" and 1862 were categorized as "no HCV infection." The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), positive likelihood ratio (LR+), and negative likelihood ratio (LR-) of each assay were as follows: the Mindray anti-HCV assay, 95.6%, 99.2%, 85.1%, 99.8%, 118.6 and 0.045, respectively; the Architect anti-HCV assay, 98.9%, 95.2%, 50.0%, 99.9%, 20.69 and 0.012, respectively; and the Elecsys anti-HCV II assay, 96.7%, 99.9%, 98.9%, 99.8%, 1799.9 and 0.033, respectively. There were significant differences in the specificity, PPV and LR+ among the three assays (P < .001). There were no significant differences in the sensitivity, NPV or LR- among the three assays (P > .05).

CONCLUSIONS

The Mindray anti-HCV assay displays a similar sensitivity to the Elecsys anti-HCV II assay with respect to the early detection of HCV infection. The Mindray anti-HCV assay shows excellent diagnostic performance and is suitable for the screening of HCV infection.

Anti-hepatitis C virus seroprevalence in the working age population in Poland, 2004 to 2014

Hepatitis C virus (HCV) infection is considered by the World Health Organization (WHO) to be a serious public health concern and one of the major public health priorities. In 2005, it was estimated that there are 185 million anti-HCV positive people in the world, which constitutes 2.8% of the global population. Our study estimates the anti-HCV seroprevalence in the working age population (15–64 years-old), mostly urban and suburban residents, in Poland from 2004 to 2014. The studied group consisted of 61,805 working-age population representatives whose data were obtained from electronic medical records of an outpatient clinic network operating on a countrywide level. Positive anti-HCV test results were obtained in 957 patients, representing 1.5% of the whole population studied throughout the analysed period. The average age of all anti-HCV positive patients was 36.8 years. Analysis of the data suggests that the proportion of anti-HCV positive patients decreased over the study period (mean positive anti-HCV = -0.0017 × year + 3.3715; R² = 0.7558). In 2004, positive results were noted among 3.2% of patients undergoing HCV antibody tests, but in 2014, the percentage of patients with a positive result stood at 1.1%. The apparent decrease affected men and women similarly. Our study also provides evidence that screening people born before 1965 could be beneficial.

Retrospective analysis on the diagnostic performances and signal-to-cut-off ratios of the Elecsys Anti-HCV II assay

BACKGROUND

Anti-HCV assays are widely used as a screening tool for HCV infection. However, diagnostic performances and effective signal-to-cut-off ratios (S/COs) for predicting true HCV infections would vary according to the assays used. Thus, we evaluated the diagnostic performances of the new Elecsys Anti-HCV assay.

METHODS

A total of 41 694 cases tested by the Elecsys Anti-HCV II assay (Roche Diagnostics, Germany) during January 2013 to December 2015 were retrospectively analyzed by comparing with the diagnosis on HCV infections determined by patients' medical records and results of laboratory tests.

RESULTS

Excluding 62 cases with unclear history of HCV infection, 430 and 41 202 cases were respectively assorted as "true infection" and "no evidence of infection," and 99.85% of the initial results by the Elecsys assay were concordant with the diagnosis on HCV infection. Sensitivity, specificity, positive and negative predictive values were respectively 99.30%, 99.86%, 88.04%, and 99.99%, where the prevalence of the HCV infection was 1.0%. The area under the receiver operating characteristics curve value of the Elecsys assay was 0.9980 (95% confidence interval [CI]=0.9944 to 1.0017). The S/CO by the Elecsys assay for predictive of a true-positive ≥95% of the time was 19.0 (95% CI=15.0 to 25.1).

CONCLUSION

The Elecsys Anti-HCV II assay showed excellent diagnostic performances, particularly in terms of sensitivity, specificity, and NPV. However, the results obtained by this assay with S/CO less than a certain value would need to be retested by HCV RNA PCR or another anti-HCV assay.

Evaluation of the Novel HISCL Chemiluminescence Enzyme Immunoassay for Laboratory Screening of Hepatitis C Virus

The hepatitis C virus (HCV) antibody assay remains the first-line screening test to identify HCV infection. The newly arrived HISCL Anti-HCV assay had a satisfactory seroconversion sensitivity. Its sensitivity and specificity were 98.97 and 100% for clinical samples. In general, the HISCL Anti-HCV assay may be a novel choice for clinical HCV screening.

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

BACKGROUND

Detection of antibodies (anti-HCV) against hepatitis C virus (HCV) is indispensable for screening and diagnosis of viral hepatitis and for the viral safety of blood, tissue or organ donations. It gains additional importance by the new HCV drugs which improve the therapeutic possibilities dramatically.

OBJECTIVE

To evaluate the performance of a newly developed immune assay for anti-HCV based on the well-established VIDAS platform.

STUDY DESIGN

The assay was evaluated with samples from anti-HCV negative blood donors and from patients with or without HCV markers in six centres in France, Spain and Egypt. The status of the samples was determined by using CE-marked immune assays (Architect, AxSym, Prism, Vitros), two immunoblots (RIBA, Inno-Lia) and/or HCV RNA results.

RESULTS

Specificity was 99.67% in 10,320 French blood donors without anti-HCV, 99.5% in 200 anti-HCV negative hospitalized European patients and 99.0% in 198 negative patients from Egypt. Sensitivity was 99.7% in 1054 patients pretested positive by other assays; 345 patients with known genotype had genotype 1-6; 61 patients were co-infected with HIV. VIDAS was reactive in 78% of 91 patients with uncertain or very weak anti-HCV. It became on average positive at day 37 with seroconversion panels.

CONCLUSIONS

This multicentric, international study with >12,000 samples show that the new VIDAS anti-HCV assay is very suitable for screening and confirmation of HCV infection. Sensitivity, specificity and recognition of seroconversion compare favorably with well-established CE-marked tests and help to clarify discrepant results obtained with other assays.

Comparison of Elecsys Anti-HCV II Assay With Other HCV Screening Assays

OBJECTIVE

Early detection of hepatitis C virus (HCV) is an important step in preventing progression to cirrhosis and hepatocellular carcinoma. Serologic assays for anti-HCV antibody are valuable first-line tests in the screening and diagnosis of HCV infection. This study's aim was to evaluate the sensitivity and specificity of Elecsys Anti-HCV II assay for HCV screening.

DESIGN AND METHODS

A total of 1,044 routine sera, 20 known HCV-positive samples, plus 54 preselected weakly positive samples were tested for anti-HCV with Elecsys Anti-HCV II assay, Elecsys Anti-HCV assays, InTec HCV enzymoimmunoassay (EIA), and Livzon Anti-HCV EIA. Interference test was assessed with additional 423 specimens without clinical evidence of HCV infection: preselected HCV weak reactive samples; dialysis samples; anti-HBc (antibody to HBV core antigen) (+), anti-Treponema pallidum (+), and anti-HIV (+) sera; and samples form autoimmune/alcoholic hepatitis or systemic Lupus erythematosus (SLE). Discrepant results were evaluated with recombinant immunoblot assay. The seroconversion panels were evaluated to assess how early each assay could detect HCV infection.

RESULTS

The specificity (99.81%) of the Elecsys Anti-HCV II assay was less than that with the two EIA comparison methods. However, false-negative results were easily seen in the EIA assays. When serial bleeds of HCV panels were compared with the above-mentioned methods, the assay detected acute HCV infection only 3.5 days after a positive HCV-RNA nucleic acid test and earlier than the comparator assays.

CONCLUSION

Sensitivities and specificities of the anti-HCV assays were sufficiently high for use in this study. The Elecsys Anti-HCV II assay is suitable for screening and reliable early detection of HCV infection.

Hepatitis C Virus Seroprevalence in Mongolian Women Assessed by a Novel Multiplex Antibody Detection Assay

BACKGROUND

Hepatitis C virus (HCV) infection causes hepatocellular carcinoma and is an important cause of mortality in both industrialized and developing countries. We developed a single-step high-throughput multiplex serology assay for HCV antibody detection and determined HCV prevalence in a highly endemic country.

METHODS

Five proteins (Core, NS3, NS4A, NS5A, NS5B) each from the three most common subtypes of HCV (1a, 1b, 2a) were recombinantly expressed and used as antigens in a multiplexed antibody detection assay. Multiplex HCV serology was validated with 432 reference sera whose HCV status was established by commercial ELISA, Western blot, and RNA assays. HCV antibodies were determined in 1,023 sera representative for the adult female population of Mongolia.

RESULTS

In reference sera, detection of HCV (mostly Core and NS3) antibodies by multiplex serology showed 100% sensitivity and 99.6% specificity, and was in very good agreement with the commercial diagnostic assays (kappa, 0.96; 95% confidence interval, 0.92-0.99). The role of antibodies to NS4 and NS5 remains to be evaluated. In Mongolia, overall HCV antibody prevalence was 18.9% (17.8% when age-standardized to the world population). HCV seroprevalence increased with age from 10% in women <30 years to 32% in women ≥50 years, but was not related to sexual risk factors.

CONCLUSIONS

The single-step high-throughput multiplex HCV serology assay performs similarly to conventional HCV antibody screening followed by secondary confirmation assays. A very high HCV seroprevalence was confirmed across all socio-economic groups in the female population of Mongolia.

IMPACT

Multiplex HCV serology facilitates large seroepidemiologic studies of HCV infection.

Head-to-head comparison between two screening systems for HBsAG, anti-HBc, anti-HCV and HIV combination immunoassays in an international, multicentre evaluation study

BACKGROUND

Mandatory screening of blood donations for hepatitis B and hepatitis C viruses and human immunodeficiency viruses 1 and 2 requires assays with exceptional sensitivity and specificity. This study reports the results from a direct head-to-head comparison of the Elecsys HBsAG II, Elecsys Anti-HBc, Elecsys Anti-HCV II and Elecsys HIV combi PT immunoassays with the respective ABBOTT PRISM/Architect instrument immunoassays in a multicentre blood bank evaluation study.

STUDY DESIGN AND METHODS

Assay validation was performed in the blood screening laboratories of four blood bank centres in Austria, Germany, Spain and Thailand, where both first-time donor samples (approximately 6000 donors) and repeat donor samples (approximately 14,000 donors) were screened.

RESULTS

Of all screened donor samples, 93 (0.46%) were confirmed to be positive using assays from both manufacturers. The specificity of all immunoassays was >99.5% and was comparable between first-time and multiple-time donors. A direct comparison between the assays from Roche and ABBOTT according to Bland and Altman analysis demonstrated equivalent quality.

CONCLUSIONS

These results suggest that the Elecsys immunoassays for HBV, HCV and HIV infection, with a comparative sensitivity of 100% and a specificity exceeding the common technical specification threshold of >99.5%, meet the stringent performance criteria stipulated for blood donor screening for these infectious agents. Significant differences in the specificity between first-time and repeat donors were not detectable.

Evaluation of the Elecsys(®) Anti-HCV II assay for routine hepatitis C virus screening of different Asian Pacific populations and detection of early infection

BACKGROUND

Early diagnosis of hepatitis C virus (HCV) infection is essential to allow appropriate treatment and prevent transmission.

OBJECTIVES

To evaluate the Elecsys(®) Anti-HCV II assay as a routine screening assay in Asia using a large number of samples from different Asian Pacific populations and compare its performance with other HCV assays routinely used in the region.

STUDY DESIGN

The sensitivity and specificity of the Elecsys(®) Anti-HCV II assay were determined using routine hospital samples and compared with at least one of the following comparator assays at nine independent centers: ARCHITECT™ Anti-HCV; Serodia(®)-HCV Particle Agglutination; Vitros(®) ECi Anti-HCV; Elecsys(®) Anti-HCV; ADVIA Centaur(®) HCV; InTec(®) HCV EIA; or Livzon(®) Anti-HCV. Commercially available seroconversion panels were used to assess sensitivity for early detection of infection.

RESULTS

The Elecsys(®) Anti-HCV II assay was more sensitive in recognizing early infection and detected acute HCV infection earlier on average than the comparator assays for all six panels tested. 7,726 routine samples were tested and 322 identified as HCV positive. Elecsys(®) Anti-HCV II had a sensitivity of 100% and a specificity of 99.66%, both of which were comparable or superior to the results obtained for competitor assays, which ranged from 87.5-100% and 98.98-100%, respectively.

CONCLUSIONS

The Elecsys(®) Anti-HCV II assay has the sensitivity and specificity to support its use as a routine screening method in the Asia Pacific region. Furthermore, this assay shortens the diagnostic window between infection and the detection of antibodies compared with established methods.

Clinical performance of the novel DiaSorin LIAISON(®) XL murex: HBsAg Quant, HCV-Ab, HIV-Ab/Ag assays

BACKGROUND

The fully automated and closed LIAISON(®)XL platform was developed for reliable detection of infection markers like hepatitis B virus (HBV) surface antigen (HBsAg), hepatitis C virus (HCV) antibodies (Ab) or human immunodeficiency virus (HIV)-Ag/Ab. To date, less is known about the diagnostic performance of this system in direct comparison to the common Abbott ARCHITECT(®) platform.

OBJECTIVES

We compared the diagnostic performance and usability of the DiaSorin LIAISON(®)XL with the commonly used Abbott ARCHITECT(®) system.

STUDY DESIGN

The qualitative performance of the above mentioned assays was compared in about 500 sera. Quantitative tests were performed for HBsAg-positive samples from patients under therapy (n=289) and in vitro expressed mutants (n=37). For HCV-Ab, a total number of 155 selected samples from patients chronically infected with different HCV genotypes were tested.

RESULTS

The concordance between both systems was 99.4% for HBsAg, 98.81% for HCV-Ab, and 99.6% for HIV-Ab/Ag. The quantitative LIAISON(®)XL murex HBsAg assay detected all mutants in comparable amounts to the HBsAg wild type and yielded highly reliable HBsAg kinetics in patients treated with antiviral drugs. Dilution experiments using the 2nd International Standard for HBsAg (WHO) showed a high accuracy of this test. HCV-Ab from patients infected with genotypes 1-3 were equally detected in both systems. Interestingly, S/CO levels of HCV-Ab from patients infected with genotype 3 seem to be relatively low using both systems.

CONCLUSIONS

The LIAISON(®)XL platform proved to be an excellent system for diagnostics of HBV, HCV, and HIV with equal performance compared to the ARCHITECT(®) system.