Isolated anti-HBc: The Relevance of Hepatitis B Core Antibody-A Review of New Issues

Clinical Significance and Remaining Issues of Anti-HBc Antibody and HBV Core-Related Antigen

Currently, hepatitis B virus (HBV) core antibody (anti-HBc antibody) and HBV core-related antigen (HBcrAg) are widely used as serum markers for diagnosis based on the HBV core region. This review focused on anti-HBc antibodies and HBcrAg and aimed to summarize the clinical significance of currently used assay systems and the issues involved. While anti-HBc is very significant for clinical diagnosis, the clinical significance of quantitative assay of anti-HBc antibody has been reevaluated with improvements in diagnostic performance, including its association with clinical stage and prediction of carcinogenesis and reactivation. In addition, concerning the new HBcrAg, a high-sensitivity assay method has recently been established, and its diagnostic significance, including the prediction of reactivation, is being reevaluated. On the other hand, the quantitative level of anti-HBc antibody expressed in different units among assay systems complicates the interpretation of the results. However, it is difficult to standardize assay systems as they vary in advantages, and caution is needed in interpreting the assay results. In conclusion, with the development of highly sensitive HBcrAg and anti-HBc antibody, a rapid and sensitive detection assay system has been developed and used in clinical practice. In the future, it is hoped that a global standard will be created based on the many clinical findings.

Associations of five blood heavy metals with hepatitis B virus infection and immunity in adults: a cross-sectional study

BACKGROUND

Heavy metal pollution has emerged as a significant concern for human health, prompting increased awareness of its potential adverse effects. While previous research has established a connection between heavy metals and liver function biomarkers, the specific relationship between heavy metals and HBV infection remains unexplored. This cross-sectional study aims to investigate the potential correlations between five blood heavy metals - lead, cadmium, mercury, manganese, and selenium - and the presence of HBsAg, HBsAb, and HBcAb in adults.

METHODS

The study utilized data from NHANES 2007-2018. Participants were classified into four groups based on their infectious status, and the association between heavy metals and HBV infection was analyzed using multiple logistic regression and stratification analysis.

RESULTS

A total of 8431 participants were included, with 5 436 classified as Susceptible, 1 765 as Vaccinated, 865 as Natural Infection, and 103 as Acute/Chronic HBV Infection. The Vaccinated group exhibited a lower mean age (34.52 ± 14.16 years) compared to the other groups. Statistically significant differences in heavy metal concentrations (except selenium) were observed among the groups (P < 0.001). After adjusting for covariates, lead was significantly associated with HBV infection (Q2: OR 2.37, 95%CI 1.04-5.39; Q3: OR 2.34, 95%CI 1.01-5.40), and positive trends were observed for high blood concentrations of mercury (Q4: OR 3.03, 95%CI 1.31-7.04) and manganese (Q4: OR 2.52, 95%CI 1.20-5.28). Furtherly, the presence of lead reduced the protection of HBsAb (Q2: OR 0.84, 95%CI 0.73-0.97; Q3: OR 0.77, 95%CI 0.66-0.90; Q4: OR 0.83, 95%CI 0.70-0.98). Subgroup analysis indicated that cadmium was associated with an increased risk of HBV infection in Asians (OR 1.36, 95%CI 1.03-1.78) and individuals with a BMI range of 25 to 30 (OR 1.60, 95%CI 1.17-2.18).

CONCLUSIONS

The study's findings suggest a correlation between elevated blood Pb concentrations and reduced immunization rates against hepatitis B. Individuals with a positive HBsAg exhibit lower blood Se concentrations and higher blood Hg and Mn concentrations.

Hepatitis B virus infection status and associated factors among health care workers in selected hospitals in Kisumu County, Kenya: A cross-sectional study

Poorly managed medical waste produced at the health facilities are potential source of infections including occupational exposure to Hepatitis B Virus (HBV). This study evaluated the prevalence of HBV infection among healthcare workers (HCWs) in Kisumu County. We determined prevalence of HBV infections among 192 HCWs from nine purposively selected high-patient volume public hospitals in Kisumu County. A structured questionnaire was administered, and 4.0 ml of venous blood sample collected for Hepatitis B surface antigen (HBsAg), hepatitis B surface antibody (anti-HBs) and total hepatitis B core antibody (anti-HBc) testing using enzyme immunoassay (EIA). Of 192 HCWs sampled, 52.1% were males and the median participants age was 34.4 years with interquartile range (IQR) of 11 (28-39) years. Most participants (44%) had worked for between 1-5 years. There was low HBV vaccine uptake with 35.9% completing the required 3 doses, while 40.6% had never been vaccinated. HBV prevalence was 18.8% (36/192), prevalence of past resolved infection was 25.5% (49/192), while 37.5% (72/192) of HCW had evidence of vaccine-derived immunity and 17.7% (34/192) were susceptible. HBV prevalence among HCW who had worked for less than one year and those who had never been vaccinated was 37.5% and 35.9% respectively. Significant risk of HBV lifetime exposure was noted among HCWs with one vaccine dose, those with no known exposure, while highest in those with knowledge on HBV transmission (aOR, 7.97; 95% CI, 2.10-153.3, p-value = 0.008). HCWs who had received ≥2 doses of HBV vaccine (aOR, 0.03; 95% CI, 0.01-0.10, p-value = <0.0001) had significant HBV protection. Duration of service was not associated with HBV among HCWs. HBV prevalence was high among HCWs from nine high patient volume public hospitals in Kisumu County. Efforts to strengthen HBV vaccination uptake and dose completion are needed to reduce HBV infections among HCWs.

Epidemiological and molecular characterization of HBV and HCV infections in HIV-1-infected inmate population in Italy: a 2017-2019 multicenter cross-sectional study

HBV/HCV co-infection is common in HIV-1-infected prisoners. To investigate the characteristics of HIV co-infections, and to evaluate the molecular heterogeneity of HIV, HBV and HCV in prisoners, we carried-out a multicenter cross-sectional study, including 65 HIV-1-infected inmates enrolled in 5 Italian detention centers during the period 2017-2019. HIV-1 subtyping showed that 77.1% of inmates were infected with B subtype and 22.9% with non-B subtypes. Italian nationals were all infected with subtype B (93.1%), except two individuals, one infected with the recombinant form CRF72_BF1, and the other with the HIV-1 sub-subtype A6, both previously not identified in inmates of Italian nationality. Non-Italian nationals were infected with subtype B (52.6%), CRFs (36.8%) and sub-subtypes A1 and A3 (5.2%). HIV variants carrying resistance mutations to NRTI, NNRTI, PI and InSTI were found in 7 inmates, 4 of which were never exposed to the relevant classes of drugs associated with these mutations. HBV and/or HCV co-infections markers were found in 49/65 (75.4%) inmates, while 27/65 (41.5%) showed markers of both HBV and HCV coinfection. Further, Italian nationals showed a significant higher presence of HCV markers as compared to non-Italian nationals (p = 0.0001). Finally, HCV phylogenetic analysis performed in 18 inmates revealed the presence of HCV subtypes 1a, 3a, 4d (66.6%, 16.7% and 16.7%, respectively). Our data suggest the need to monitor HIV, HBV and HCV infections in prisons in order to prevent spreading of these viruses both in jails and in the general population, and to implement effective public health programs that limit the circulation of different genetic forms as well as of viral variants with mutations conferring resistance to treatment.

Prevalence of overt and occult hepatitis B virus infection among an incarcerated population of Central-Western Brazil

Brazilian prison complexes are characterized by overcrowded cells and precarious conditions, leading to chronically low vacancy. Brazilian studies involving overt and occult infection (OBI) in this population are still scarce despite the vulnerability of people deprived of liberty to hepatitis B. Therefore, this study estimated the prevalence of HBV infection (overall and OBI) in individuals deprived of liberty in prisons in Central-Western Brazil. In addition, factors associated with HBV infection were evaluated. This cross-sectional study was conducted with a total of 1083 prisoners who were tested for serological hepatitis B markers and HBV DNA from 2017 to 2020. Factors associated with lifetime HBV infection were investigated using logistic regression. An overall prevalence of HBV infection of 10.1% (95% CI: 8.42-12.11) was detected. Only 32.8% (95% CI: 30.08-35.76) had isolated anti-HBs positivity (serological evidence of HBV vaccination). Indeed, more than half of the population was susceptible to HBV infection (57.1%; 95% CI: 54.15-60.13). HBV DNA was detected in one HBsAg-positive sample (n=1/9; 11%). Also, HBV DNA was detected in five HBsAg-negative samples (n=5/1074), resulting in a prevalence of 0.5% (95% CI: 0.15-1.08) for occult infection. After the multivariate analysis, sexual intercourse with a partner living with HIV was a predictor independently associated with HBV exposure (OR: 4.3; 95% CI: 1.26-14.55; p<0.020). These data demonstrate the need for preventive measures, mainly aimed at health education and better strategies for hepatitis B screening to control this infection in prisons more effectively.

Effect of Anti-HBs on Mortality Among Resolved HBV Infection: a Population-Based Prospective Cohort Study

INTRODUCTION

Surveillance programs after hepatitis B surface antigen (HBsAg) loss are not yet well established, and the role of hepatitis B surface antibodies (anti-HBs) remains controversial. We aimed to evaluate the risk factors for increased mortality and the association between anti-HBs and all-cause and cause-specific mortality in a representative US (United States) population of patients with resolved HBV (Hepatitis B virus) infections.

METHODS

Data were taken from the US National Health and Nutrition Examination Survey (NHANES) 1999-2018. A total of 3455 US adults with resolved HBV infection [defined as hepatitis B surface antigen (HBsAg) negative/anti-hepatitis B core antigen (anti-HBc) positive] were enrolled in this study. The primary outcome measures were all-cause and cause-specific mortality from baseline until 31 December 2019.

RESULTS

During a mean follow-up of 10.3 years, 741 deaths occurred. Age, race, marital status, smoking status, physical activity level, and presence of cirrhosis, diabetes, cardiovascular diseases, chronic obstructive pulmonary diseases, cancer, and anti-HBs were significant factors for increased mortality, and a nomogram tool was developed and validated for the risk stratification of mortality. Compared with participants who were anti-HBs positive, those who were anti-HBs negative had a 23% (hazard ratio 1.23, 95% CI 1.02-1.46) higher risk of all-cause mortality in NHANES 1999-2018. For cause-specific mortality, the fully adjusted hazard ratios of participants who were anti-HBs negative were 0.71 (95% CI 0.48-1.06) for heart disease, 1.44 (95% CI 1.01-2.05) for cancer, and 1.44 (95% CI 1.13-1.83) for other conditions, compared to those of participants who were anti-HBs positive.

CONCLUSIONS

Among US adults with resolved HBV infections, anti-HBs-negative status was associated with an increased risk of death from all causes and cancer, implying that the role of anti-HBs in resolved HBV infection should not be ignored. On the public health level, more rigorous surveillance was needed for populations of individuals who were isolated anti-HBc positive.

Hepatitis B burden and population immunity in a high endemicity city - a geographically random household epidemiology study for evaluating achievability of elimination

This study aimed to provide reference for evaluating the achievability of hepatitis B virus (HBV) elimination in a high endemicity city with universal neonatal vaccination in place for over 30 years. Between September 2018 and October 2020, 2085 citizens from 1143 geographically random households in Hong Kong completed a questionnaire and had blood-testing for HBV markers (anti-HBs, HBsAg, anti-HBc, HBeAg). We evaluated the epidemiology and examined factors associated with HBV exposure, vaccination and chronic diseases. The proportion of households with HBsAg positive index participants was 9.2% (95% CI 7.5%-10.9%). The age- and sex-adjusted HBsAg prevalence was 6.3% (95% CI 5.3%-7.4%), compared to >10% in those born in 1960-1970 and among non-local born citizens, and <1% in people born after introduction of neonatal vaccination. Among 155 HBsAg positive participants, 59% were aware of their infection status with 10% on treatment and 10/150 (6.7%) HBeAg positive. More than 40% (872/2064) tested negative for both HBsAg and anti-HBs, contributed by the lack of immunity in older adults and the waning immunity of vaccines. Hong Kong has remained at high-intermediate HBV endemicity state. The moderate level of anti-HBs positivity and very low treatment coverage (10%) among HBsAg positive participants pose challenges for achieving the HBV elimination target.

Isolated Hepatitis B Core Antibody Positivity and Long-Term Liver-Related Mortality in Korea: A Cohort Study

INTRODUCTION

Whether isolated hepatitis B core antibody (anti-HBc) positivity is a risk factor for long-term liver-related outcomes in hepatitis B virus (HBV)-endemic areas remains unclear. We aimed to investigate liver-related and liver cancer mortality of isolated anti-HBc positivity in Korean adults.

METHODS

A cohort study comprised 609,299 Korean adults who underwent hepatitis B serologic markers, as a part of health examination. Liver-related and liver cancer mortality were determined using the National Death Records.

RESULTS

During a median follow-up of 9.0 years (interquartile range, 5.5-13.7 years), 554 liver-related deaths were identified (liver-related mortality, 9.6 cases per 10 5 person-years). The prevalence of isolated anti-HBc positivity was 3.8% (n = 23,399) and was age-dependent. After adjustment for age, sex, and other confounders, hazard ratios (95% confidence interval) for liver-related mortality in isolated anti-HBc-positive and hepatitis B surface antigen-positive subjects compared with HBV-unexposed subjects were 1.69 (1.22-2.33) and 27.02 (21.45-34.04), respectively. These associations were pronounced in the analyses using liver cancer mortality as an outcome. Among isolated anti-HBc-positive patients, the risks of liver-related and liver cancer mortality were significantly higher in those with high fibrosis-4 scores compared with patients unexposed to HBV with the multivariable-adjusted hazard ratios (95% confidence interval) of 15.59 (9.21-26.37) and 72.66 (36.96-142.86), respectively.

DISCUSSION

In this cohort of Korean adults, isolated anti-HBc positivity was associated with an increased risk of liver-related and liver cancer mortality, especially when accompanied by a high fibrosis score. Isolated anti-HBc positivity may be an independent risk factor for liver-related outcomes, especially in high-endemic areas.

Isolated anti-HBc is an independent risk factor for tumor recurrence in intrahepatic cholangiocarcinoma after curative resection

BACKGROUND

Intrahepatic cholangiocarcinoma (ICC) is a poorly understood and aggressive malignancy with increasing incidence and mortality. Hepatitis B virus (HBV) infection is recognized as one of the important risk factors of ICC. There are few reports focusing on whether isolated antibody to hepatitis B core antigen (isolated anti-HBc, IAHBc) have prognostic role in ICC, while positive hepatitis B surface antigen (HBsAg) has been reported to be associated with the prognosis of ICC. The aim of this study was to investigate the prognostic value of IAHBc in ICC patients after curative resection, in order to identify those who have the high risk of ICC recurrence in the early stage.

METHODS

We divided 209 ICC patients who underwent curative resection into 4 groups: group I (n = 40), HBsAg (-)/antibody to hepatitis B surface antigen (anti-HBs) (-)/anti-HBc (+); group II (n = 70), HBsAg (+)/anti-HBc (-); group III (n = 55), HBsAg (-)/anti-HBs (+)/anti-HBc (+); and group IV (n = 44), HBsAg (-)/anti-HBc (-). We compared the recurrence-free survival (RFS) and overall survival (OS) among these four groups.

RESULTS

The median follow-up time was 16.93 months (range 1-34.6 months). The 1- and 2-year RFS and OS rates were 60% and 42%, and 78% and 63% respectively in all patients. Compared to the whole non-IAHBc patients (group II + group III + group IV), IAHBc patients (group I) showed significantly lower RFS at 1 year (39.8% vs. 64.4%, P = 0.001) and 2 years (20.7% vs. 46.7%, P = 0.001). When compared to other three individual groups, IAHBc patients (group I) also had the lowest RFS. We did not find significant difference in OS among the four groups. Further multivariate analysis revealed that IAHBc was an independent risk factor of RFS.

CONCLUSIONS

IAHBc is an independent poor prognostic factor for tumor recurrence in ICC patients after curative resection.

Anti-HBc IgG Responses Occurring at the Early Phase of Infection Correlate Negatively with HBV Replication in a Mouse Model

Anti-HBc IgG is usually recognized as a diagnostic marker of hepatitis B, while the functional role anti-HBc IgG in HBV infection has not been fully elucidated. In this study, we firstly investigated the relationship between the anti-HBc IgG responses and the replication of HBV using AAV8-1.3HBV infected C57BL/6N mice. Our data showed that the anti-HBc IgG responses at the early phase of infection correlated negatively with the concentrations of circulating HBsAg and HBV DNA at both the early and chronic phases of infection. This observation was confirmed by an independent experiment using AAV8-1.3HBV infected C57BL/6J mice. Furthermore, to comprehend the potential causal relationship between the anti-HBc IgG responses and HBV infection, mice were treated with an anti-HBc monoclonal antibody at three days post AAV8-1.3HBV infection. Our data showed that the anti-HBc mAb significantly suppressed the fold increase of circulating HBsAg level, and the protective effect was not affected by NK cell depletion. Collectively, our study demonstrated that anti-HBc antibodies occurring at the early phase of HBV infection may contribute to the constraint of the virus replication, which might be developed as an immunotherapy for hepatitis B.

HBV seroprevalence and liver fibrosis status among population born before national immunization in Southern Thailand: Findings from a health check-up program

Background

Hepatitis B virus (HBV) infection is the leading cause of liver-related death worldwide, particularly in Asia. Patients with either current or past HBV infection are at risk of cirrhosis and hepatocellular carcinoma (HCC). Here, we investigated the HBV seroprevalence in residents of southern Thailand born before the national vaccination program.

Methods

A cross-sectional study of individuals born before the nationwide HBV vaccination program who sought check-up programs which included HBV serology and abdominal ultrasound at a tertiary care hospital in southern Thailand from 2019 to 2020 was conducted. HBV serology, cirrhosis and liver fibrosis status (determined by ultrasonography and FIB-4), and clinical notes regarding management following HBsAg+ detection were obtained.

Results

Of 1,690 eligible individuals, the overall prevalence of HBsAg+ and HBsAg-antiHBc+, indicating current and past HBV infections, were 2.9% and 27.8%, respectively. Among current HBV patients, 87.8% were unaware of their infection. Cirrhosis was found in 8.2%, 1.1%, and 0.3% of patients with current, past, and no HBV infection, respectively (p<0.001). One-fourth of past HBV patients had FIB-4≥1.45, which indicated indeterminate or significant liver fibrosis, which may increase the risk of HCC.

Conclusion

The prevalence of HBsAg+ in Southern Thailand was 2.9%, and that of past infection (HBsAg-antiHBc+) was 27.8%. Patients with current and past HBV infection have an increased risk of cirrhosis and significant liver fibrosis. Most current HBV patients were unaware of their infection. Identifying patients with current and past HBV infection who are at risk for HCC and linking them to a cascade of care is necessary to reduce the burden of HBV-related liver diseases in Thailand.

Blood Lead Exposure and Association With Hepatitis B Core Antibody in the United States: NHANES 2011–2018

The objective of this project was to explore the distribution and related factors of blood lead and the association between blood lead and hepatitis B core antibody (HBcAb). All the data were from the U.S. National Health and Nutrition Examination Survey (NHANES). In total, 15,097 (aged 20–80 years) participants were included. Participants without a history of blood transfusion were more likely to be exposed to lower levels of blood lead [−2.30 (−3.13, −1.47) for HBcAb (–) and −2.23 (−4.54, 0.08) for HBcAb (+)]. The odds ratio (OR) of HBcAb (+) increased with blood lead and the result was 1.09 (1.06, 1.12). This study showed that older adults, men, people with a lower education level, a lower ratio of family income to poverty (PIR), a lower body mass index (BMI), or a history of blood transfusion, people who lived with a companion or with a total number of people in the family >3, people living in the United States for a longer time, U.S. citizens by birth or naturalization, and people not born in the United States were associated with higher blood lead exposure, and blood lead had a positive association with HBcAb (+).

Significance of anti-HBc serological status in primary immune thrombocytopenia

The association of previous hepatitis B virus (HBV) exposure [hepatitis B surface antigen (HBsAg) negative, hepatitis B core antibody (anti-HBc/HBcAb) positive] with disease severity and decision on treatment option in primary immune thrombocytopenia (ITP) patients remains unclear. Data from 725 patients diagnosed with ITP were analyzed to elucidate the association between anti-HBc serological status and disease severity. Data from a published prospective study [high-dose dexamethasone (HD-DXM), HD-DXM plus recombinant human thrombopoietin, NCT01734044] and two retrospective studies (standard-dose and low-dose rituximab) were rearranged to evaluate the impact of anti-HBc serological status on the response and outcome to ITP-specific treatments and the risk of HBV reactivation related to these treatments. The prevalence of HBsAg^- HBcAb⁺ and HBsAg^- HBcAb^- in ITP patients was 51·03% and 48·97% respectively. Compared to the HBsAg^- HBcAb^- group, patients in the HBsAg^- HBcAb⁺ group had lower platelet count, higher bleeding score, and longer hospitalization (P = 0·002, 0·033, and 0·008 respectively). Moreover, the initial complete response rate of HBsAg^- HBcAb⁺ patients was lower than that of HBsAg^- HBcAb^- patients (45·2% vs 59·8%, P = 0·027). In conclusion, previous HBV exposure was correlated with disease severity and hospitalization in ITP patients. Anti-HBc positivity may be considered as a predictor for poor response to ITP-specific treatments.

A Study of Prevalence of Occult Hepatitis B Virus Infection, Knowledge and Preventive Practices Against Hepatitis B Virus in Barbers Serving the Armed Forces

OBJECTIVE

Hepatitis B virus (HBV) infection is a major health problem in the world. Barbers deal with frequent abrasions/lacerations due to sharp equipment, making them a high-risk group. Determination of HBsAg positive status excludes most reservoirs of transmission in the population. However, Occult Hepatitis B continues to be a source of transmission. The aim of this study was to study the prevalence of occult HBV infection in barbers serving the armed forces clientele and evaluate their knowledge and preventive practices against HBV transmission.

METHODS

Seventy-nine HBsAg negative barbers were included in this study and interviewed for the status of immunisation and preventive practices. Anti-HBc total and HBV DNA levels were measured along with a complete haemogram, LFT, PT INR, ultrasound abdomen and Fibroscan of the liver.

RESULTS

The prevalence of occult Hepatitis B status was 3.79%. Among barbers who were anti-HBc total positive, 100% were found to have replicative HBV DNA status. All barbers (100%) were unaware of the existence and modes of HBV transmission and were never screened for HBV; 98.73% of barbers followed improper disinfection practices and were never immunised.

CONCLUSION

The prevalence of occult HBV infection in barbers, absence of immunisation, unawareness and improper disinfection practices are significantly at risk for transmission to the unaware clients. It is important to educate barbers, establish a universal disinfection procedure and implement a system of compulsory Hepatitis B vaccination before the commencement of their trade work.

Association of anti-HBc and liver inflammation in HBeAg-negative chronic hepatitis B virus-infected patients with normal ALT and detectable HBV DNA

Serum hepatitis B core antibody (anti-HBc) is associated with liver inflammation in chronic hepatitis B patients. This study aimed to investigate whether anti-HBc could serve as a predictor of significant liver inflammation in hepatitis B e antigen (HBeAg)-negative chronic hepatitis B virus (HBV) infected patients with normal alanine aminotransferase (ALT) and detectable HBV DNA. Treatment-naïve HBeAg-negative chronic HBV infected patients with normal ALT and detectable HBV DNA who underwent liver biopsy were retrospectively included from two medical centers. Liver inflammation grade was evaluated using the Scheuer scoring system and significant liver inflammation was defined as ≥G2. Serum anti-HBc levels were measured by commercial immunoassays (Abbott GmbH & Co. KG). A total of 117 patients were included and 50 (42.7%) patients showed significant liver inflammation. Serum anti-HBc levels in patients with significant liver inflammation were significantly higher than patients with no or mild liver inflammation (<G2) (p < 0.001). High serum anti-HBc (odds ratio 1.562, 95% confidential interval 1.157-2.110, p = 0.004) was an independent risk factor of significant liver inflammation. The area under the receiver operating characteristic curve of serum anti-HBc in predicting significant liver inflammation was 0.769 and the optimal cut-off value was 10.87 S/CO, with a sensitivity of 59.2% and a specificity of 87.9%. Our data revealed that a substantial of HBeAg-negative chronic infection patients with normal ALT and detectable HBV DNA showed significant liver inflammation. Serum anti-HBc can predict significant liver inflammation in these patients.

Estimated prevalence and number of persons with isolated antibody to hepatitis B core antigen and associated occult hepatitis B, United States, 2001-2018

Persons with isolated antibody to HBV core antigen (IAHBc) may have occult HBV infection (OBI), which is associated with reactivation and potential risk for hepatocellular carcinoma and HBV transmission. We used National Health and Nutrition Examination Survey (NHANES) data to estimate US IAHBc prevalence and published studies of IAHBc-associated OBI prevalence to estimate OBI burden. During 2001-2018, IAHBc prevalence was 0.8% (approximately 2.1 million persons); OBI burden range was 35,500-83,600 persons. These data support the need for more robust estimates of IAHBc-associated OBI prevalence in the general US population.

Prediction of hepatic inflammation in chronic hepatitis B patients with a random forest-backward feature elimination algorithm

BACKGROUND

Persistent liver inflammatory damage is the main risk factor for developing liver fibrosis, cirrhosis, and even hepatocellular carcinoma in chronic hepatitis B (CHB) patients. Thus, accurate prediction of the degree of liver inflammation is a high priority and a growing medical need.

AIM

To build an effective and robust non-invasive model for predicting hepatitis B-related hepatic inflammation.

METHODS

A total of 650 treatment-naïve CHB (402 HBeAg-positive and 248 HBeAg-negative) patients who underwent liver biopsy were enrolled in this study. Histological inflammation grading was assessed by the Ishak scoring system. Serum quantitative hepatitis B core antibody (qAnti-HBc) levels and 21 immune-related inflammatory factors were measured quantitatively using a chemiluminescent microparticle immunoassay. A backward feature elimination (BFE) algorithm utilizing random forest (RF) was used to select optional features and construct a combined model. The diagnostic abilities of the model or variables were evaluated based on the estimated area under the receiver operating characteristics curve (AUROC) and compared using the DeLong test.

RESULTS

Four features were selected to predict moderate-to-severe inflammation in CHB patients using the RF-BFE method. These predictive features included qAnti-HBc, ALT, AST, and CXCL11. Spearman’s correlation analysis indicated that serum qAnti-HBc, ALT, AST, and CXCL11 levels were positively correlated with the histology activity index (HAI) score. These selected features were incorporated into the model to establish a novel model named I-3A index. The AUROC [0.822; 95% confidence interval (CI): 0.790-0.851] of the I-3A index was significantly increased compared with qAnti-HBc alone (0.760, 95%CI: 0.724-0.792, P < 0.0001) in all CHB patients. The use of an I-3A index cutoff value of 0.41 produced a sensitivity of 69.17%, specificity of 81.44%, and accuracy of 73.8%. Additionally, the I-3A index showed significantly improved diagnostic performance for predicting moderate-to-severe inflammation in HBeAg-positive and HBeAg-negative CHB patients (0.829, 95%CI: 0.789-0.865 and 0.810, 95%CI: 0.755-0.857, respectively).

CONCLUSION

The selected features of the I-3A index constructed using the RF-BFE algorithm can effectively predict moderate-to-severe liver inflammation in CHB patients.

Treatment of Hepatitis C Genotypes 1 to 5 in Sub-Saharan Africa Using Direct-Acting Antivirals

There is limited knowledge of the use of direct acting antivirals (DAAs) for the treatment of hepatitis C virus (HCV) in sub-Saharan Africa. We prospectively evaluated individuals infected with HCV genotypes 1 to 5 in Addis Ababa, Ethiopia. Liver fibrosis was assessed by AST-platelet ratio index score and cirrhosis by imaging and laboratory values. All 164 individuals completed treatment. The majority of patients had genotype 4 (76%), and 19% of participants showed evidence of cirrhosis. Sustained virologic response (SVR) across all genotypes was 98.8%. In those with cirrhosis, SVR was 93.5% and in non-cirrhotics 100%. Our study demonstrates broad genotype successful treatment of HCV with DAAs in sub-Saharan Africa, demonstrating the feasibility of HCV elimination in resource-limited settings.

Positive Hepatitis B Core Antibody Is Associated With Cirrhosis and Hepatocellular Carcinoma in Nonalcoholic Fatty Liver Disease

OBJECTIVES

Previous exposure to hepatitis B virus (HBV) may increase the risk of hepatocellular carcinoma (HCC) in patients with chronic hepatitis C. We aim to study the impact of previous HBV infection on the severity and outcomes of patients with nonalcoholic fatty liver disease (NAFLD).

METHODS

This was a multicenter study of 489 patients with biopsy-proven NAFLD and 69 patients with NAFLD-related or cryptogenic HCC. Antihepatitis B core antibody (anti-HBc) was used to detect the previous HBV infection.

RESULTS

In the biopsy cohort, positive anti-HBc was associated with lower steatosis grade but higher fibrosis stage. 18.8% and 7.5% of patients with positive and negative anti-HBc had cirrhosis, respectively (P < 0.001). The association between anti-HBc and cirrhosis remained significant after adjusting for age and metabolic factors (adjusted odds ratio 2.232; 95% confidence interval, 1.202-4.147). At a mean follow-up of 6.2 years, patients with positive anti-HBc had a higher incidence of HCC or cirrhotic complications (6.5% vs 2.2%; P = 0.039). Among patients with NAFLD-related or cryptogenic HCC, 73.9% had positive anti-HBc. None of the patients had positive serum HBV DNA. By contrast, antihepatitis B surface antibody did not correlate with histological severity.

DISCUSSION

Positive anti-HBc is associated with cirrhosis and possibly HCC and cirrhotic complications in patients with NAFLD. Because a significant proportion of NAFLD-related HCC may develop in noncirrhotic patients, future studies should define the role of anti-HBc in selecting noncirrhotic patients with NAFLD for HCC surveillance.

Characterization of occult hepatitis B in high-risk populations in Kenya

Occult hepatitis B infection (OBI) is defined as the presence of hepatitis B virus (HBV) DNA in the liver or serum in the absence of detectable HBV surface antigen (HBsAg). OBI poses a risk for the development of cirrhosis and hepatocellular carcinoma. The prevalence of OBI in Kenya is unknown, thus a study was undertaken to determine the prevalence and molecular characterization of OBI in Kenyan populations at high risk of HBV infection. Sera from two Nairobi cohorts, 99 male sex workers, primarily having sex with men (MSM-SW), and 13 non-MSM men having HIV-positive partners, as well as 65 HBsAg-negative patients presenting with jaundice at Kenyan medical facilities, were tested for HBV serological markers, including HBV DNA by real-time PCR. Positive DNA samples were sequenced and MSM-SW patients were further tested for hepatitis C virus (HCV) infection. Of the 166 HBsAg-negative samples tested, 31 (18.7%; 95% confidence interval [CI] 13.5–25.3) were HBV DNA positive (i.e., occult), the majority (20/31; 64.5%) of which were HBV core protein antibody positive. HCV infection was not observed in the MSM-SW participants, although the prevalence of HBsAg positivity was 10.1% (10/99; 95% CI 5.6–17.6). HBV genotype A was predominant among study cases, including both HBsAg-positive and OBI participants, although the data suggests a non-African network transmission source among MSM-SW. The high prevalence of HBV infection among MSM-SW in Kenya suggests that screening programmes be instituted among high-risk cohorts to facilitate preventative measures, such as vaccination, and establish entry to treatment and linkage to care.

Baseline Level of Hepatitis B Core Antibody Predicts Spontaneous Hepatitis B e Antigen (HBeAg) Seroconversion in HBeAg-Positive Children With a Normal Alanine Aminotransferase Level

It is not clear whether baseline hepatitis B core antibody (anti-HBc) level in hepatitis B e antigen (HBeAg)-positive children with a normal alanine aminotransferase (ALT) level is predictive of spontaneous HBeAg seroconversion. We investigated the correlation between anti-HBc level and the natural course of chronic hepatitis B (CHB) virus (HBV) infection in children, particularly the ability of baseline anti-HBc level to predict spontaneous HBeAg seroconversion during long-term follow-up. HBeAg-positive children with untreated CHB and a normal ALT level were followed longitudinally. Anti-HBc level was determined by double-sandwich immunoassay. Effects of anti-HBc levels and other parameters on spontaneous HBeAg seroconversion and the natural course of CHB were assessed. A total of 182 children (106 males) with a median age at enrollment of 10.6 years (interquartile range [IQR], 10.3-15.3) were followed for a median of 19.8 years (IQR, 11.9-21.9). Spontaneous HBeAg seroconversion occurred in 85 children (46.7%) during the follow-up. A baseline anti-HBc titer of >500 IU/mL (hazard ratio [HR] = 2.81), HBV genotype B and B + C (HR = 3.46), and a baseline hepatitis B surface antigen titer of ≤4.8 log₁₀  IU/mL (HR = 3.09) were predictive of spontaneous HBeAg seroconversion, based on multivariable survival analysis (P < 0.001). In cases remaining HBeAg positive, their anti-HBc levels increased gradually during follow-up because of ongoing inflammation. Conclusion: Baseline anti-HBc level is predictive of spontaneous HBeAg seroconversion in HBeAg-positive children with a normal ALT level. Anti-HBc level reflects anti-HBV immune response in the HBeAg-positive normal ALT phase of CHB.

Prevalence and characteristics of occult hepatitis B virus infection in Japanese human immunodeficiency virus-infected patients

Occult hepatitis B virus (HBV) infection (OBI) is hepatitis B surface antigen (HBsAg) negative but with detectable HBV DNA. Although HIV infection has been reported to be a risk factor for OBI, the prevalence and clinical features of OBI in Japanese HIV infected patients have not been documented. This retrospective, single-center study was conducted to determine the prevalence and characteristic of OBI in Japanese antiretroviral therapy (ART) naïve HIV infected patients. OBI was defined as the presence of serum HBV DNA but without detectable HBsAg. Of the 147 ART naïve HIV infected patients, OBI was detected in 9 (6.1%) patients; 2 (4.3%) of 47 with both anti-HBs and anti-HBc positive, 6 (27.3%) of 22 with anti-HBc alone, and 1 (2.0%) of 50 with both anti-HBs and anti-HBc negative. The mean HBV DNA level was low at 28.7 ± 18.2 IU/mL. The proportion of OBI patients with anti-HBc alone was significantly higher than that of non-OBI patients (66.7% vs 14.5%, P = 0.001). In addition, the prevalence of AIDS (acquired immunodeficiency syndrome)-defining illnesses in the OBI group was significantly higher than in the non-OBI group (77.8% vs 35.5%, P = 0.001). No significant difference was found in the CD4 count or alanine aminotransferase levels of these two groups. This is the first study to reveal the prevalence and clinical features of OBI in Japanese HIV-infected patients. The persistence of anti-HBc alone and AIDS-defining illnesses were associated with the occurrence of OBI in these patients.

Effective Use of the Laboratory in the Management of Patients with Inflammatory Bowel Diseases

Inflammatory bowel disease (IBD) comprises a group of chronic, intestinal inflammatory disorders, including ulcerative colitis and Crohn's disease. IBD is characterized by periods of relapse and remission. Long-term progressive intestinal inflammation can result in severe and devastating complications, such as intestinal strictures and/or fistulae. Immune suppressive medications with potent side effects are often used to control inflammation and limit disease activity. Laboratory tests guide various decisions in clinical management of IBD. We discuss tests used to diagnose IBD, assess for relapse or remission, monitor the effectiveness of therapeutic regimen, screen for the maintenance of health, and diagnose or prevent complications.

The burden of HBV infection in HCV patients in Italy and the risk of reactivation under DAA therapy

BACKGROUND

There is increasing awareness of HBV reactivation in HCV-RNA-positive/HBV-coinfected patients with chronic liver disease (CLD) treated with oral direct-acting antivirals (DAAs).

AIM

To provide figures on the prevalence of HBV markers in HCV-RNA-positive subjects in Italy, where these findings are lacking.

METHODS

All subjects aged ≥18 years with CLD consecutively referring to Italian liver units located throughout country were prospectively enrolled in two national surveys in 2001 and 2014.

RESULTS

The total number of HCV-RNA-positive cases was 6984; 356 (5.1%) subjects vaccinated against HBV were excluded. A total of 6628 cases were evaluated. The prevalence rates of HBsAg, isolated anti-HBc and anti-HBc/anti-HBs-positivity were 2.9%, 8.1% and 14.7%, respectively. Among the estimated one million HCV-RNA-positive subjects in Italy, a substantial number of subjects are at risk of HBV reactivation due to DAA therapy. The prevalence of liver cirrhosis was higher than that of CLD in HBsAg-positive subjects (4.4% vs. 2.6%, p < 0.01) but not in those positive for other HBV markers.

CONCLUSIONS

These findings outline the burden of HBV markers among HCV-RNA-positive subjects in Italy, where in 2017 reimbursement for DAA therapy by the National Health System became universal for all patients with chronic HCV infection. HBV vaccination coverage should be greatly extended, since nearly two thirds of subjects in this study resulted negative for any HBV marker.

Management of Hepatitis B Virus Infection: 2018 Guidelines from the Canadian Association for the Study of Liver Disease and Association of Medical Microbiology and Infectious Disease Canada

Hepatitis B virus (HBV) infection is an important public health problem in Canada. In keeping with evolving evidence and understanding of HBV pathogenesis, the Canadian Association for the Study of Liver Disease periodically publishes HBV management guidelines. The goals of the 2018 guidelines are to (1) highlight the public health impact of HBV infection in Canada and the need to improve diagnosis and linkage to care, (2) recommend current best-practice guidelines for treatment of HBV, (3) summarize the key HBV laboratory diagnostic tests, and (4) review evidence on HBV management in special patient populations and include more detail on management of HBV in pediatric populations. An overview of novel HBV tests and therapies for HBV in development is provided to highlight the recent advances in HBV clinical research. The aim and scope of these guidelines are to serve as an up-to-date, comprehensive resource for Canadian health care providers in the management of HBV infection.

Short article: Hepatitis delta in patients with resolved hepatitis B virus infection

BACKGROUND

The hepatitis delta virus (HDV) causes the most aggressive form of chronic viral hepatitis. As HDV replication requires hepatitis B virus (HBV), HDV screening is limited to HBsAg+ carriers. To date, individuals with HDV-antibodies and markers of resolved hepatitis B are considered cured. However, a subset shows elevated liver enzymes and hepatic fibrosis. Could they represent HBsAg-seronegative occult HDV infections?

METHODS

We tested for HDV-antibodies 406 individuals with markers of past HBV exposure.

RESULTS

Overall, 20 (4.9%) were reactive for HDV-antibodies. All were negative for serum HDV-RNA, including four with elevated liver enzymes.

CONCLUSION

These results support the current policy of screening for hepatitis delta only in HBsAg+ individuals.

The dynamics of integration, viral suppression and cell-cell transmission in the development of occult Hepatitis B virus infection

BACKGROUND

Out of several phases of HBV infection, the least understood phase is occult hepatitis B virus infection. The paucity of data due to non-availability of biological tissues and the prerequisite of ultra-sensitive assays for the detection of occult hepatitis B virus infection prompted us to utilize mathematical modeling in determining mechanisms that lead to occult hepatitis B virus infection and characteristics of HBV infection during occult hepatitis B virus infection.

METHODS

We proposed two mathematical models (M1 and M2), considering two different phenomenon for episomal maintenance and accumulation of covalently closed circular DNA (cccDNA) in infected hepatocytes: (i) M1 - recirculation of the relaxed circular DNA/double-stranded linear DNA from cytoplasm to the nucleus, and (ii) M2 - reinfection of infected hepatocytes with virions. We further incorporated the dynamics of integrated Hepatitis B virus DNA (iHBV) to investigate its role in the development of occult hepatitis B virus infection.

RESULTS

The analysis showed that the main mechanism for the spread of infection during occult hepatitis B virus infection is cell-to-cell transmission and not cell-free virus transmission. A significant viral suppression (of at least 99% from its peak production values) was essential but not sufficient in the development of occult hepatitis B virus infection under M1; however under M2, the viral suppression was neither sufficient nor essential as the inhibition of the production of HBsAg without viral suppression can also explain the development of occult hepatitis B virus infection. Our analysis also revealed that occult hepatitis B virus infection seropositive cases are more likely to progress into liver cirrhosis compared to occult hepatitis B virus infection seronegative cases. The iHBV was found to be mostly silent (by either being absent or non-productive for HBsAg) during occult hepatitis B virus infection.

CONCLUSION

The viral suppression is neither essential nor sufficient to explain the development of occult hepatitis B virus infection on its own. Not only the viral suppression but the inhibition -of the production and the export of HBsAg from cccDNA and iHBV also plays an important role in the development of occult hepatitis B virus infection. This is the first study, which incorporates the dynamics of iHBV and shows that HBV primarily spreads via cell-cell transmission during occult hepatitis B virus infection.

Hepatitis B virus reactivation in patients treated with immunosuppressive drugs: a practical guide for clinicians

Hepatitis B virus reactivation (HBVr) is emerging as an important clinical entity, with the advent of highly potent immunosuppression licensed for use as the treatment of a widening range of clinical indications. HBVr can lead to severe acute liver failure and death. Risk can be minimised through appropriate screening, monitoring and antiviral prophylaxis. Screening for serological markers at the -earliest opportunity is recommended. Risk stratification should then be performed on the basis of characteristics of the -underlying disease, markers of viral activity and the potency of proposed immunosuppression. In this review, we summarise the most recent recommendations from the relevant international societies. We also provide suggestions on how a robust multidisciplinary service can be delivered to prevent HBVr in UK clinical practice through optimisation of resources and introduction of checkpoints to prevent the inappropriate administration of immunosuppression to those at significant risk of HBVr.