Performance characteristics of a combined hepatitis C virus core antigen and anti-hepatitis C virus antibody test in different patient groups

Performance of Elecsys® HCV Duo Immunoassay for Diagnosis and Assessment of Treatment Response in HCV Patients with or without HIV Infection

BACKGROUND/OBJECTIVES

The Elecsys® HCV Duo immunoassay (Roche Diagnostics International Ltd., Rotkreuz, Switzerland) detects both antibodies to hepatitis C virus (anti-HCV) and HCV core antigen (HCV-Ag) and has shown excellent diagnostic performance in blood donor samples. We aim to validate its use for diagnosing chronic HCV infection and assessing sustained virological response (SVR) post-direct-acting antivirals (DAAs) in patients with or without HIV infection.

METHODS

Blood samples from 100 healthy controls, as well as 64 HCV mono-infection and 136 HCV-HIV coinfections, were collected before and 12-24 weeks after DAAs. The assay performance for determining active infection at baseline and SVR was compared with HCV RNA.

RESULTS

Overall, 156 (78.0%) of HCV-infected patients had HCV genotype 1, and the SVR rate was 96.5%. The sensitivity, specificity, and area under the ROC curve (AUROC) for HCV diagnosis at baseline were 99.50% (95% confidence interval [CI], 96.82-99.97%), 100% (95%CI, 95.39-100%), and 0.998 (95%CI, 0.992-1.003), respectively. The corresponding results for HCV-Ag in determining SVR were 57.14% (95%CI, 20.24-88.19%), 97.41% (95%CI, 93.73-99.04%), and 0.773 (95%CI, 0.543-1.003), respectively. The assay also exhibited comparable sensitivity and specificity between HCV mono- and coinfection.

CONCLUSIONS

Our study showed that the Elecsys® HCV Duo immunoassay effectively diagnosed HCV infection, regardless of HIV status, making it suitable for managing high-risk populations in resource-limited settings.

Comparison of two immunoassays for concurrent detection of HCV antigen and antibodies among HIV/HCV co-infected patients in dried serum/plasma spots

Hepatitis C virus (HCV) antigen/antibody (Ag/Ab) assays offer the benefit of reducing the window period compared to assays that detect only HCV-Ab. In this study the performance of the Murex Ag/Ab (Murex, Abbott) and Monolisa Ag/Ab Ultra (Monolisa, Bio-Rad) ELISAs was compared for the use of filter dried serum/plasma spots (DS/PS) with a focus on the sensitivity and the percentage of correct positive test results. Correct positive ELISA results were assumed for samples that subsequently tested positive for HCV RNA by RT-qPCR, or RNA negative samples that tested positive in a Western blot (confirmed ELISA results). Sensitivity was evaluated from DS/PS eluates using HCV seroconversion panels [plasma samples of subtypes-(St) 1a, 2b)] and longitudinal HCV antibody positive serum panels (St 1b, 2b, 3a, and 4d). The proportion of correct positive test results was evaluated using 1102 newly diagnosed HIV positive clinical dried serum spots (DSS) eluates for screening of potential HCV co-infection. For the plasma HCV seroconversion samples, which were used as a reference for DSS eluates, the Murex became reactive earlier for antigen positive bleeds. However, for the HCV antibody positive eluates and dilutions thereof, the Monolisa demonstrated a superior sensitivity. Of the clinical DSS 22.8 % (28/123) of samples reactive in the Murex were negative in a subsequent RT-qPCR and Western blot, while only 1.9 % (2/105) of the samples reactive in the Monolisa were negative in these confirmatory assays. Our results indicate that the Monolisa provides fewer false positive results for HCV detection in DSS, whereas for undiluted plasma or serum samples, the Murex can serve as an additional diagnostic tool to narrow the window period.

Rapid and Sensitive Detection of Hepatitis C Virus in Clinical Blood Samples Using Reverse Transcriptase Polymerase Spiral Reaction

This study established a new polymerase spiral reaction (PSR) that combines with reverse transcription reactions for HCV detection targeting 5'UTR gene. To avoid cross-contamination of aerosols, an isothermal amplification tube (IAT), as a separate containment control, was used to judge the result. After optimizing the RT-PSR reaction system, its effectiveness and specificity were tested against 15 different virus strains which included 8 that were HCV positive and 7 as non-HCV controls. The results showed that the RT-PSR assay effectively detected all 8 HCV strains, and no false positives were found among the 7 non-HCV strains. The detection limit of our RT-PSR assay is comparable to the real-time RT-PCR, but is more sensitive than the RT-LAMP. The established RT-PSR assay was further evaluated for detection of HCV in clinical blood samples, and the resulting 80.25% detection rate demonstrated better or similar effectiveness compared to the RT-LAMP (79.63%) and real-time RT-PCR (80.25%). Overall, the results showed that the RT-PSR assay offers high specificity and sensitivity for HCV detection with great potential for screening HCV in clinical blood samples.

Diagnostic accuracy of tests to detect Hepatitis C antibody: a meta-analysis and review of the literature

BACKGROUND

Although direct-acting antivirals can achieve sustained virological response rates greater than 90% in Hepatitis C Virus (HCV) infected persons, at present the majority of HCV-infected individuals remain undiagnosed and therefore untreated. While there are a wide range of HCV serological tests available, there is a lack of formal assessment of their diagnostic performance. We undertook a systematic review and meta-analysis to evaluate he diagnostic accuracy of available rapid diagnostic tests (RDT) and laboratory based EIA assays in detecting antibodies to HCV.

METHODS

We used the PRISMA checklist and Cochrane guidance to develop our search protocol. The search strategy was registered in PROSPERO (CRD42015023567). The search focused on hepatitis C, diagnostic tests, and diagnostic accuracy within eight databases (MEDLINE, EMBASE, the Cochrane Central Register of Controlled Trials, Science Citation Index Expanded, Conference Proceedings Citation Index-Science, SCOPUS, Literatura Latino-Americana e do Caribe em Ciências da Saúde and WHO Global Index Medicus. Studies were included if they evaluated an assay to determine the sensitivity and specificity of HCV antibody (HCV Ab) in humans. Two reviewers independently extracted data and performed a quality assessment of the studies using the QUADAS tool. We pooled test estimates using the DerSimonian-Laird method, by using the software R and RevMan. 5.3.

RESULTS

A total of 52 studies were identified that included 52,673 unique test measurements. Based on five studies, the pooled sensitivity and specificity of HCV Ab rapid diagnostic tests (RDTs) were 98% (95% CI 98-100%) and 100% (95% CI 100-100%) compared to an enzyme immunoassay (EIA) reference standard. High HCV Ab RDTs sensitivity and specificity were observed across screening populations (general population, high risk populations, and hospital patients) using different reference standards (EIA, nucleic acid testing, immunoblot). There were insufficient studies to undertake subanalyses based on HIV co-infection. Oral HCV Ab RDTs also had excellent sensitivity and specificity compared to blood reference tests, respectively at 94% (95% CI 93-96%) and 100% (95% CI 100-100%). Among studies that assessed individual oral RDTs, the eight studies revealed that OraQuick ADVANCE® had a slightly higher sensitivity (98%, 95% CI 97-98%) compared to the other oral brands (pooled sensitivity: 88%, 95% CI 84-92%).

CONCLUSIONS

RDTs, including oral tests, have excellent sensitivity and specificity compared to laboratory-based methods for HCV antibody detection across a wide range of settings. Oral HCV Ab RDTs had good sensitivity and specificity compared to blood reference standards.

Who to test and how to test for chronic hepatitis C infection - 2016 WHO testing guidance for low- and middle-income countries

Testing and diagnosis of hepatitis C virus (HCV) infection is the gateway for access to both treatment and prevention services, and crucial for an effective hepatitis epidemic response. In contrast to HIV, a systematic approach to hepatitis C testing has been fragmented and limited to a few countries, and there remains a large burden of undiagnosed cases globally. Key challenges in the current hepatitis testing response, include lack of simple, reliable, and low cost diagnostic tests, laboratory capacity, and testing facilities; inadequate data to guide country-specific hepatitis testing approaches and who to test; stigmatization and social marginalization of some groups with or at risk of viral hepatitis; and lack of international or national guidelines on hepatitis testing for resource-limited settings. New tools to support the hepatitis global response include the 2016 Global Hepatitis Health Sector Strategy which include targets for testing and diagnosis, and World Health Organization (WHO) 2016 hepatitis testing guidelines for adults, adolescents, and children in low- and middle-income countries. The testing guidance complements recent published WHO guidance on the prevention, care and treatment of chronic hepatitis C and hepatitis B infection. These testing guidelines outline the public health approach to strengthening and expanding current testing practices for HCV and HBV and address what serological and virological assays to use, and who to test, as well as interventions to promote linkage to prevention and care after testing. They are intended for use across all age groups and populations. See boxes for key recommendations. Future directions and innovations in viral hepatitis testing include use of point-of-care assays for nucleic acid testing (NAT) and core antigen; validation of dried blood spots specimens with different commercial serological and NAT assays; multiplex and polyvalent platforms for integrated testing of HIV, HBV and HCV; and potential for self-testing.

MicroRNA let-7g cooperates with interferon/ribavirin to repress hepatitis C virus replication

MicroRNAs (miRNA) have been implicated in HCV infection. The present study analyzed the effects of let-7g on HCV infection in vitro, in clinical tissue and serum samples. Here, we show that the expression of let-7g in serum and liver tissue is significantly higher in patients with sustained virologic response (SVR). We show that interferon (IFN)/ribavirin (RBV) induces let-7g expression through p38/AP-1 signaling. Overexpression of let-7g reduced HCV gene or core protein level and inhibited the HCV viral load. The let-7g and IFN/RBV have additively inhibitory effect on HCV replication. These data implicate let-7g as a new therapeutic drug to additively cooperate with IFN/RBV to repress HCV replication. Key messages: let-7g expression is increased in serum and liver tissue of patients with SVR. Interferon/ribavirin induces let-7g expression through p38/AP-1 signaling. Overexpression of let-7g can repress HCV replication. Let-7g additively cooperates with interferon/ribavirin to repress HCV replication. Lin28B silencing can reverse let-7g expression and repress HCV replication.

Huge gap between clinical efficacy and community effectiveness in the treatment of chronic hepatitis C: a nationwide survey in Taiwan

Peginterferon/ribavirin provides a substantially high treatment efficacy for chronic hepatitis C virus (HCV) infections in Asians. Whether the clinical efficacy can be translated to community effectiveness remains unclear. The disease awareness, treatment accessibility, recommendations, acceptance, and barriers to anti-HCV treatment were explored to clarify the issue with a 3-step nationwide investigation in Taiwan. A crude HCV-infected population was estimated using databases from 3 large-scale surveillance studies and age-/geographic-specific population database. HCV awareness and accessibility were investigated at the patient level in 58,129 residents. The recommendations/acceptances and barriers to treatment at the provider level were evaluated using a prospective, nationwide approach to 89 gastroenterologists/hepatologists. The estimated 10-year interval age-adjusted anti-HCV-seropositive population is 745,109 (3.28%), with an anticipated HCV-viremic population of 554,361. Of anti-HCV-seropositive subjects, 36.2% had disease awareness. Among those with awareness, 39.6% had accessibility. The recommendation/acceptance rate of antiviral therapy was 70.6%. The treatment rate was 10.1% and 13.7% for the anti-HCV-seropositive and HCV-viremic population, respectively. With an anticipated treatment success rate of 80% in Taiwan, 8.1% of the anti-HCV-seropositive and 10.9% of the HCV-viremic population achieved successful treatment. The major treatment barriers were fear of adverse effects (37%), major disorders (17.6%), ineligibility for insurance reimbursement (17.6%), and lack of therapy awareness (11.3%). Despite the high rates of treatment response and nationwide coverage of insurance reimbursement, there remains a large gap between clinical efficacy and community effectiveness in anti-HCV treatment in Taiwan. Increasing disease awareness/treatment accessibility and introducing new therapeutic strategies with high tolerability are warranted.

Hepatitis C virus infection increases risk of developing end-stage renal disease using competing risk analysis

Background

Chronic kidney disease (CKD) and hepatitis C virus (HCV) infection are closely linked and both increase patient mortality. The association of HCV and risk of developing end-stage renal disease (ESRD) has not been analyzed with competing risk model.

Method

We enrolled a prospective cohort of 4,185 patients (mean age, 62 years; 41% female) registered in the CKD integrated care program at two affiliated hospitals of Kaohsiung Medical University in Taiwan between November 11, 2002 and May 31, 2009. With competing risk model, we analyzed the association of HCV infection, defined by seropositive of anti-HCV antibody, and hepatitis B virus (HBV) infection, defined by seropositive of HBV surface antigen, with the risk of entering ESRD.

Results

The prevalence of HCV infection was 7.6% and it increased with the CKD stages (trend test, P<0.001), while the prevalence of HBV infection was 7.4% and no specific trend among CKD stages (tend test, P = 0.1). During the 9,101 person-year follow-up period, there were 446 death and 1,205 patients entering ESRD. After adjusting death as the competing risk, the estimated 5-year cumulative incidence rate of ESRD among patients with and without HCV infection were 52.6% and 38.4%, respectively (modified log-rank, P<0.001). Multivariable analysis showed that HCV infection, but not HBV infection, had higher risk of developing ESRD compared with cases without infection (HCV, HR: 1.32, 95% CI: 1.07–1.62; HBV, HR: 1.10, 95% CI: 0.89–1.35). Subgroup analyses showed consistent results.

Conclusions

With death-adjusted competing risk analysis, HCV infection is associated with an increased risk of developing ESRD in CKD cohort.

Epidemiology and impact of HIV coinfection with hepatitis B and hepatitis C viruses in Sub-Saharan Africa

Human immunodeficiency virus (HIV), Hepatitis B (HBV) and Hepatitis C (HCV) are blood-borne viruses with potentially shared routes of transmission. In high-income settings, the impact of antiretroviral therapy (ART) on survival has unmasked chronic liver disease from viral hepatitis B or hepatitis C as a leading cause of morbidity and mortality in individuals with HIV infection. It is now feared that progressive liver disease may threaten the success of ART programmes in developing countries, where HCV or HBV testing and monitoring are not yet systematic among HIV-infected patients and ART use is generally blind to these co-infections. We set out to review recent data from Sub-Saharan Africa, in order to build a detailed and up-to-date picture of the epidemiology and emerging impact of HBV and HCV coinfection in countries at the heart of the HIV pandemic. There is a preponderance of HIV/HBV coinfection compared to HIV/HCV in this region, and significant caveats exist regarding the accuracy of published HCV seroprevalence surveys. Morbidity and mortality of coinfection is significant, and may be further enhanced in African populations due to the influence of host, viral and environmental factors. Careful scrutiny of the coinfection problem is vital to inform an approach to directing resources, planning public health initiatives, providing clinical care, and guiding future research.

Hepatitis C virus infection among injection drug users with and without human immunodeficiency virus co-infection

The aim of this study is to explore the prevalence of hepatitis C virus (HCV) infection among injection drug users (IDUs) with and without human immunodeficiency virus (HIV) infection in southern Taiwan. For 562 IDUs (265 anti-HIV negative, 297 anti-HIV positive), we analyzed liver function, anti-HIV antibody, anti-HCV antibody, HCV viral loads, and hepatitis B surface antigen (HBsAg). HIV RNA viral loads and CD4 cell count for anti-HIV-seropositive IDUs and the HCV genotype for HCV RNA-seropositive IDUs were measured. The seroprevalence rates of anti-HIV, anti-HCV, and HBsAg were 52.8%, 91.3%, and 15.3%, respectively. All the anti-HIV-seropositive IDUs were positive for HIV RNA. Anti-HCV seropositivity was the most important factor associated with HIV infection (odds ratio [OR], 25.06; 95% confidence intervals [CI], 8.97-74.9), followed by male gender (OR, 6.12; 95% CI, 4.05-9.39) and HBsAg seropositivity (OR, 1.90; 95% CI, 1.11-3.34). Among IDUs positive for anti-HCV, 80.7% had detectable HCV RNA. HCV viremia after HCV exposure was strongly related to HIV infection (OR, 6.262; 95% CI, 1.515-18.28), but negatively correlated to HBsAg seropositivity (OR, 0.161; 95% CI, 0.082-0.317). HCV genotype 6 was the most prevalent genotype among all IDUs (41.0%), followed by genotypes 1 (32.3%), 3 (12.8%), and 2 (5.6%). In conclusion, about half IDUs were infected with HIV and >90% with HCV infection. Male and seropositivity for HBsAg and anti-HCV were factors related to HIV infection among our IDUs. HIV was positively correlated, whereas hepatitis B co-infection was negatively correlated with HCV viremia among IDUs with HCV exposure. Different HCV molecular epidemiology was noted among IDUs.

Peripheral blood mononuclear cells microRNA predicts treatment outcome of hepatitis C virus genotype 1 infection

BACKGROUNDS

Chronic hepatitis C virus (HCV) infection has been associated with induction of microRNAs (miRNAs) in peripheral blood mononuclear cells (PBMC). We aimed to evaluate the role of PBMC-miRNAs in the treatment outcome to antiviral therapy for HCV genotype 1 (HCV-1) patients.

METHODS

Treatment-naive chronic HCV-1 patients, including 13 in screening phase and 48 in validation phase, were treated with 48weeks of peginterferon/ribavirin. The primary end-point was the achievement of a sustained virological response (SVR, HCV RNA undetectable during 24weeks post-treatment follow-up). Expression profiling of PBMC-miRNAs was performed by quantitative PCR-based array in typical responders and null-responders. Then candidate PBMC-miRNAs were validated by quantitative PCR in an independent validation set.

RESULTS

PBMC-miR-125b was significantly predictive of an SVR, with expression levels of 5.28-fold lower in sustained responders versus null-responders (p=0.0163). In multivariate analysis, PBMC-miR-125b was significantly associated with the achievement of SVR (per 2-fold decrease, odds ratio/95% confidence interval (OR/CI): 2.07/1.14-6.31) independent of sex, age and interleukin-28B genotype. In patients who did not achieve a rapid virological response (RVR, undetectable HCV RNA at treatment week 4), PBMC-miR-125b was the only predictive factor of an SVR (per 2-fold decrease, OR/CI: 2.07/1.14-6.31). However, the circulating and hepatic miR-125b did not show significant difference between responders and non-responders.

CONCLUSIONS

PBMC-miR-125b expression levels were inversely related to the achievement of an SVR in HCV-1 patients, independent of interleukin-28B genotype, and was the single predictor of SVR in non-RVR patients.

High hepatitis B virus surface antigen levels and favorable interleukin 28B genotype predict spontaneous hepatitis C virus clearance in uremic patients

BACKGROUND & AIMS

Host and viral factors interplay in the spontaneous clearance of hepatitis C virus (HCV) infection. We aimed to explore the roles of IL28B genotypes and hepatitis B virus (HBV) infections in spontaneous HCV seroclearance.

METHODS

IL28B rs8099917 genotypes, HCV and HBV markers were determined in 290 patients who were seropositive for HCV antibodies from 1681 total uremic patients on maintenance hemodialysis.

RESULTS

Persistent HCV viremia was observed in 74.6% (214/287) of patients. Logistic regression revealed that the strongest factors associated with spontaneous HCV seroclearance were carriage of rs8099917 TT-type (odds ratio/95% confidence intervals [OR/CI]: 6.22/1.41-27.35, p=0.016), followed by concurrent hepatitis B surface antigen (HBsAg) seropositivity (OR/CI: 2.37/1.06-5.26, p=0.035). The clearance rate was highest among patients with both positive HBsAg/rs8099917 TT-type (44.8%, OR/CI: 20.88/3.5-402.5), followed by positive HBsAg/rs8099917 non-TT-type (28.6%, OR/CI: 8.86/1.8-160.8), and negative HBsAg/rs8099917 TT-type (26.7%, OR/CI: 12.75/1.0-319.4), compared to 4% of negative HBsAg/rs8099917 non-TT-type (trend p=0.0002). HBsAg levels, but not HBV DNA levels, were significantly associated with spontaneous HCV seroclearance. Spontaneous HCV seroclearance rate was 58.3% in patients with HBsAg>200IU/ml/rs8099917 TT-type (OR/CI: 42.54/5.7-908.4), 28.0% in patients with HBsAg<200IU/ml/rs8099917 TT-type or HBsAg>200IU/ml/rs8099917 non-TT-type (OR/CI: 11.12/2.3-201.0), compared to only 3.3% in those with HBsAg<200IU/ml/rs8099917 non-TT-type (trend p=0.0004). Five of 214 (2.3%) HCV viremic patients at enrollment had spontaneous HCV seroclearance during one-year follow-up, which was associated with baseline HCV RNA and HBsAg levels.

CONCLUSIONS

High HBsAg levels and favorable IL28B genotype were additively associated with spontaneous HCV seroclearance in uremic patients.

Simultaneous detection of hepatitis C virus antigen and antibodies in dried blood spots

BACKGROUND

Enzyme immunoassays (EIA) designed to detect hepatitis C virus (HCV) core antigen and anti-HCV antibodies (HCV AgAb) simultaneously can improve the early detection of HCV infection when molecular diagnostic methods are not widely available.

OBJECTIVES

To evaluate the suitability of dried blood spot (DBS) samples for detecting HCV AgAb using commercial EIAs.

STUDY DESIGN

Paired serum and DBS samples were assayed using two commercial EIAs for HCV AgAb (Monolisa™ HCV AgAb ULTRA and Murex HCV AgAb). Manufacturer's recommendations were followed for sera while sample volume, incubation time and cut-off (CO) determination were evaluated for the DBS samples. The values of sensitivity, specificity, inter-rater agreement, detection limit, assay precision and stability of DBS samples at different conditions (22-26°C, 2-8°C and -20°C) were determined.

RESULTS

It was necessary to increase the DBS sample volume fourfold compared to the sera samples to approximate the DBS Optical Density (OD) values to the sera OD values. Using ROC curve to recalculate CO values for the DBS samples, sensitivity was 97.5% for both EIAs, while the specificity was 99.71% for Monolisa™ HCV AgAb ULTRA and 95.95% for Murex HCV AgAb. Accurate testing results were obtained with DBS samples for 60 days at all conditions evaluated; storage at -20°C resulted in low OD variation. Both EIAs demonstrated the same limit of detection among DBS samples [estimated viral load of 3.1 International Units per millilitre (IU/mL)] and low OD value variability in repetitivity and reproducibility studies.

CONCLUSION

DBS samples can be used for the detection of HCV AgAb by EIA as they present comparable performance characteristics and excellent stability among various storage conditions.

APASL consensus statements and management algorithms for hepatitis C virus infection

The Asian Pacific Association for the Study of the Liver (APASL) convened an international working party on the "APASL Consensus Statements and Management Algorithms for Hepatitis C Virus Infection" in December, 2010, in order to revise "Asian Pacific Association for the Study of the Liver consensus statements on the diagnosis, management and treatment of hepatitis C virus infection (J Gastroenterol Hepatol 22:615-633, 2007)". The working party consisted of expert hepatologists from the Asian-Pacific region gathered at Makuhari, Chiba, Japan on 19 December 2010. New data were presented, discussed and debated to draft a revision. Participants of the consensus meeting assessed the quality of cited studies. Finalized recommendations are presented in this review.