Feasibility of anti-HCV reflex HCV Ag screening strategy in an HCV endemic community

Hepatitis C Virus-Core Antigen: Implications in Diagnostic, Treatment Monitoring and Clinical Outcomes

The hepatitis C virus (HCV) infection, a global health concern, can lead to chronic liver disease. The HCV core antigen (HCVcAg), a viral protein essential for replication, offers a cost-effective alternative to HCV RNA testing, particularly in resource-limited settings. This review explores the significance of HCVcAg, a key protein in the hepatitis C virus, examining its structure, function, and role in the viral life cycle. It also evaluates its clinical use in diagnosis and treatment monitoring, comparing its performance to the standard HCV RNA assay using data from PubMed and Google Scholar. HCVcAg assays show high pooled sensitivity (93.5%) and pooled specificity (99.2%) compared to HCV RNA assays, correlating closely (r = 0.87) with HCV RNA levels. Hence, HCVcAg testing offers a cost-effective way to diagnose active HCV infections and monitor treatment, especially in resource-limited settings, but its sensitivity can vary and standardization is needed. HCVcAg also predicts liver disease progression and assesses liver damage risk, aiding patient management. It helps to identify patients at risk for fibrosis or carcinoma, making it vital in hepatitis C care. HCVcAg testing can expand access to HCV care, simplify management, and contribute to global elimination strategies, especially in low- and middle-income countries.

Dual strategy involving hospital-based study and community-based screening to eliminate hepatitis C in remote areas

BACKGROUND

/Purpose: To achieve the World Health Organization goal of eliminating viral hepatitis by 2030, a key strategy in resource-limited areas is to identify the areas with high prevalence and to prioritize screening and treatment intervention. We hypothesized that a hospital-based laboratory database could be used to estimate the township- and village-specific anti-hepatitis C virus (HCV) prevalence.

METHODS

Yunlin County Public Health Bureau has been collecting anti-HCV test data from eight major hospitals. Township- and village-specific screening testing rates and anti-HCV prevalence were calculated for residents 40 years or older. A township with a wide range of anti-HCV prevalence rates was selected for outreach universal screening and for validating the village-specific prevalence of anti-HCV in the analysis of the data from the hospitals.

RESULTS

The overall anti-HCV screening testing rate in Yunlin County was 30.4 %, whereas the anti-HCV prevalence rate for persons 40 years or older was 15.4 %. The village-specific anti-HCV prevalence rates ranged from 3.8 % to 85.8 %. Community-based screening was conducted in Kouhu Township. The village-specific anti-HCV prevalence rates ranged from 0 % to 18.8 %. Three of the four villages had the highest village-specific anti-HCV prevalence in the community-based study and the hospital-based study. Additionally, 95.8 % of the new HCV cases detected by universal screening received anti-HCV therapy.

CONCLUSION

The hospital-based database provided a framework for identifying the villages with high anti-HCV prevalence. Additionally, community-based universal screening should be prioritized for villages with high prevalence in hospital-based databases.

High prevalence of fatty liver and its association with metabolic syndrome among rural adults with chronic hepatitis C: Implications for primary healthcare

BACKGROUND

Chronic hepatitis C (CHC) virus infection is a global health concern that is associated with significant liver-related morbidity and mortality. Owing to the inflammatory pathway, CHC can causefatty liver, liver cirrhosis, and liver cancer and is associated with cardiometabolic diseases, such as hypertension and diabetes. Fatty liver is associated with metabolic disorders, cardiovascular diseases, diabetes, and liver cancer. Hence, the early detection of fatty liver through noninvasive screening in adults with CHC is important in primary healthcare settings. This study aimed to explore the prevalence of fatty liver and its association with metabolic syndrome amongrural adults with CHC.

METHODS

This was a series of cohort studies related to the elimination of the CHC burden around the western coastal Yunlin County, Taiwan, between August 2018 and July 2021. A cross-sectional study was conducted after hepatitis C virus RNA confirmation in a hepatitis C- endemic area. A gastrointestinal physician or radiologist assessed fatty liver by ultrasonography. Fatty liver was classified into four grades: normal, mild, moderate, and severe. Three liver enzyme biomarkers were identified. According to the Taiwan national standard, metabolic syndrome was defined based on the presence of three or more of the five abnormal biomarkers, including increased waist circumference, elevated blood pressure, elevated fasting blood glucose level, elevated triglyceride level, and low high-density lipoprotein cholesterol level.

RESULTS

A total of 256 rural adults with CHC were enrolled. The mean age of the participants was 67.5 (standard deviation = 11.8) years, with a low educational level. High prevalence of fatty liver (79%), central obesity (54.3%), elevated blood pressure (55.5%),elevated fasting blood glucose (FBG) level (44.9%), and metabolic syndrome (37.9%) were observed.The results showed that adults with CHC with moderate to severe fatty liver were significantly associated with an increased risk of increased waist circumference (P < 0.001), increased blood pressure (P < 0.001), low high-density lipoprotein cholesterol level (P < 0.05), and elevated liver enzyme biomarker levels (all P < 0.05) after adjusting for age, sex, and educational level. Furthermore, adults with CHC with moderate to severe fatty liver were significantly associated with a greater risk of metabolic syndrome (odds ratio = 2.85, 95% confidence interval = 1.66 to 4.92).

CONCLUSIONS

The findings demonstrate a high prevalence of fatty liver in rural adults with CHC, which is significantly associated with obesity, metabolic syndrome, and elevated liver biomarker levels. Clinicians and primary healthcare providers must encourage patients with CHC to receive antiviral therapy combined with weight loss management and lifestyle modification, allowing general improvements in their liver and cardiometabolic health.

TASL, TADE, and DAROC consensus for the screening and management of hepatitis C in patients with diabetes

Diabetes mellitus (DM) and hepatitis C virus (HCV) infection are prevalent diseases globally and emerging evidence demonstrates the bidirectional association between the two diseases. Direct-acting antivirals (DAAs) for HCV have a high treatment success rate and can significantly reduce the risks of short and long-term complications of HCV infection. However, despite the evidence of the association between diabetes and HCV and the benefits of anti-HCV treatment, previously published guidelines did not focus on the universal HCV screening for patients with diabetes and their subsequent management once confirmed as having HCV viremia. Nonetheless, screening for HCV among patients with diabetes will contribute to the eradication of HCV infection. Thus, the three major Taiwan medical associations of diabetes and liver diseases endorsed a total of 14 experts in the fields of gastroenterology, hepatology, diabetology, and epidemiology to convene and formulate a consensus statement on HCV screening and management among patients with diabetes. Based on recent studies and guidelines as well as from real-world clinical experiences, the Taiwan experts reached a consensus that provides a straightforward approach to HCV screening, treatment, and monitoring of patients with diabetes.

Diagnostic performance of hepatitis C core antigen assay to identify active infections: A systematic review and meta-analysis

Hepatitis C virus (HCV) core antigen (HCVcAg) assay is an alternative for diagnosing HCV infection in a single step. This meta-analysis aimed to evaluate the Abbott ARCHITECT HCV Ag assay's diagnostic performance (validity and utility) for diagnosing active hepatitis C. PubMed, EMBASE, Scopus, Web of Science, and Cochrane Library were searched until 10 January 2023. The protocol was registered at the prospective international register of systematic reviews (PROSPERO: CRD42022337191). Abbott ARCHITECT HCV Ag assay was the test for evaluation, and nucleic acid amplification tests with a cut-off ≤50 IU/mL were the gold standard. Statistical analysis was performed using STATA with the MIDAS module and random-effects models. The bivariate analysis was conducted on 46 studies (18,116 samples). The pooled sensitivity was 0.96 (95% CI = 0.94-0.97), specificity 0.99 (95% CI = 0.99-1.00), positive likelihood ratio 141.81 (95% CI = 72.39-277.79), and negative likelihood ratio 0.04 (95% CI = 0.03-0.06). The area under the summary receiver operating characteristic curve was 1.00 (95% CI = 0.34-1.00). For active hepatitis C prevalence values of 0.1%-15%, the probability that a positive test was a true positive was 12%-96%, respectively, indicating that a confirmatory test should be necessary, particularly with a prevalence ≤5%. However, the probability that a negative test was a false negative was close to zero, indicating the absence of HCV infection. The validity (accuracy) of the Abbott ARCHITECT HCV Ag assay for screening active HCV infection in serum/plasma samples was excellent. Although the HCVcAg assay showed limited diagnostic utility in low prevalence settings (≤1%), it might help diagnose hepatitis C in high prevalence scenarios (≥5%).

Community-based screening by Anti-HCV reflex HCV Ag test and accessible post-screening care toward elimination of hepatitis C in two hyperendemic townships

BACKGROUND

Hyperendemic townships of hepatitis C virus (HCV) infection should devote extra efforts to eliminate HCV. We aimed to evaluate efficacy of the screening and linkage to care in two HCV hyperendemic townships.

METHODS

Village-to-village HCV screening using anti-HCV reflex HCV Ag test was conducted in two HCV hyperendemic rural townships (Lioujiao and Yijhu). All residents aged 30 years or older were invited. Those patients detected as infected were referred to nearby hospitals or clinics in Lioujiao and to an accessible outreach hepatology clinic in Yijhu.

RESULTS

The populations of Lioujiao and Yijhu townships at time of survey were 18,389 and 14,787 with 6086 (33.1%) and 4604 (31.1%) having ever been previously screened, and 1517 and 1071 responded to this screening respectively. Their crude screening coverage rates were 41.5% and 38.5%, and adjusted screening coverage rates were 54.3% and 94.6% respectively. The prevalence rates of anti-HCV and HCV Ag were 17.9% and 11.9% in Lioujiao, and 9.2% and 5.6% in Yijhu respectively, with their rates of antigenemia (HCV Ag/anti-HCV) being 62.1% and 60.6% respectively. Numbers needed to test (NNT) to find a candidate for anti-viral treatment were 9 and 18. For linkage to care, treatment rate by referral (Lioujiao) was slightly lower than by accessible outreach hepatology clinic (Yijhu) (84.9% vs. 93.3%, p = 0.093). Overall successful sustained virological response rate at week 12 was 98.2% (161/164) in outreach hepatology clinic.

CONCLUSION

Since NNT was low, it was worthwhile conducting intensive screening in these hyperendemic townships. For high treatment rate, accessible outreach hepatology clinic is feasible especially in areas without adequate medical resources.

Community-Based Screening for Hepatitis B and C Infectivity Using Two Quantitative Antigens to Identify Endemic Townships

Screening and linkage to care are essential to achieve viral hepatitis elimination before 2030. The accurate identification of endemic areas is important for controlling diseases with geographic aggregation. Viral activity drives prognosis of chronic hepatitis B and hepatitis C virus infection. This screening was conducted in Chiayi County from 2018–2019. All residents aged 30 years or older were invited to participate in quantitative HBsAg (qHBsAg) and HCV Ag screening. Among the 4010 participants (male:female = 1630:2380), the prevalence of qHBsAg and HCV Ag was 9.9% (396/4010) and 4.1% (163/4010), respectively. High-prevalence townships were identified, three for qHBsAg > 15% and two for HCV Ag > 10%. The age-specific prevalence of qHBsAg was distributed in an inverse U-shape with a peak (16.0%, 68/424) for subjects in their 40 s; for HCV, prevalence increased with age. Concentrations of qHBsAg < 200 IU/mL were found in 54% (214/396) of carriers. The rate of oral antiviral treatment for HCV was 75.5% (114/151), with subjects younger than 75 years tending to undergo treatment (85.6% vs. 57.4%, p < 0.001). QHBsAg and HCV Ag core antigens can reflect the concentration of the viral load, which serves as a feasible screening tool. Using quantitative antigen screening for hepatitis B and C in community-based screening, two hyperendemic townships were identified from an endemic county.

Village-to-village screening for hepatitis B and C using quantitative HBsAg and anti-HCV testing with reflex HCV core antigen tests in the remote communities of a resource-rich setting: a population-based prospective cohort study

OBJECTIVES

Community-based screening for hepatitis B virus (HBV) and hepatitis C virus (HCV) is essential for hepatitis elimination. This study attempted to increase screening accessibility and efficacy by using alternative tools.

DESIGN

Population-based prospective cohort study.

SETTING

Hepatitis elimination program at Yunlin County, Taiwan.

PARTICIPANTS

All 4552 individuals participated in 60 screening sessions of a community-based HBV and HCV screening project in five rural townships with approximately 95 000 inhabitants in central-western Taiwan.

INTERVENTIONS

To increase accessibility, 60 outreach screening sessions were conducted in 41 disseminative sites. Quantitative HBV surface antigen (qHBsAg) and anti-HCV testing with reflex HCV core antigen (HCV Ag) tests were employed as alternative screening tools.

MAIN OUTCOME MEASURES

Calculate village-specific prevalence of HBsAg, anti-HCV and HCV Ag and establish patient allocation strategies according to levels of qHBsAg HCV Ag and alanine aminotransferase (ALT).

RESULTS

Of 4552 participants, 553, 697 and 290 were positive for HBsAg, anti-HCV and HCV Ag, respectively; 75 of them had both HBsAg and anti-HCV positivity. The average (range) number of participants in each screening session was 98 (31-150). The prevalence rates (range) of HBsAg, anti-HCV and HCV Ag were 12.1% (4.3%-19.4%), 15.3% (2.6%-52.3%) and 6.4% (0%-30.2%), respectively. The HCV Ag positivity rate among anti-HCV-positive participants was 42% (0%-100%). Using cut-off values of >200 IU/mL for qHBsAg, >3 fmol/L for HCV Ag and >40 IU/mL for ALT as criteria for patient referral, we noted an 80.2% reduction in referral burden. Three villages had high anti-HCV prevalences of 52.3%, 53.8% and 63.4% with corresponding viraemic prevalences of 23.2%, 30.1% and 22% and thus constituted newly identified HCV-hyperendemic villages.

CONCLUSION

Outreach hepatitis screening increases accessibility for residents in rural communities. Screening HBV and HCV through qHBsAg and HCV Ag tests provides information concerning viral activities, which might be conducive to precise patient allocation in remote communities.

HCV core antigen plays an important role in the fight against HCV as an alternative to HCV-RNA detection

Objective

To discuss the clinical significance of HCV‐cAg testing in the diagnosis, activity determination, and monitoring of therapeutic effectiveness of HCV infection and its advantages compared with HCV‐RNA and anti‐HCV antibodies detection.

Methods

By summarizing the published literature, the advantages and significance of HCV core antigen detection were sought.

Results

The expression of HCV‐cAg is highly consistent with that of HCV‐RNA, but compared with HCV‐RNA, detection of HCV‐cAg is easy to operate, time saving, and low cost. HCV‐cAg can be detected within 12~15 days after infection, and the window period can be shortened by5~7 weeks. HCV‐cAg is a serological indicator of virus replication, which can distinguish previous infection of HCV or current infection. HCV‐cAg detection is more suitable for immunocompromised, hemodialysis, organ transplant patients. HCV‐cAg also can be used to monitor antiviral efficacy and predict sustained virological response (SVR).

Conclusion

HCV core antigen has similar clinical sensitivity to NAT and can be used as a substitute for HCV‐RNA in the diagnosis of virus infection. Combined detection of HCV‐cAg and antibody serology can help doctors detect HCV infection earlier, accurately diagnose different stages of HCV infection, and evaluate the therapeutic effect of antiviral drugs, which are beneficial in the prevention and treatment of hepatitis C.