Hepatitis B virus maintains its pro-oncogenic properties in the case of occult HBV infection

Occult hepatitis B virus infection: risk for a blood supply, but how about individuals' health?

The implementation of effective blood donation screening for hepatitis B virus (HBV) anti-core antibodies with highly sensitive molecular HBV DNA detection in low-endemic countries like the United Kingdom has improved blood safety. However, the linkage to care and management for blood donors with occult HBV infection (OBI) is a complex dilemma involving virological, clinical, methodological, and social issues. Limited evidence suggests that OBI may accelerate the progression of liver disease and cancer. The need for a specialist referral for donors identified with OBI carries mixed opinions from blood establishments, hepatologists, and public health. Following extensive multidisciplinary discussions, experts agree upon a need for clear messaging for donors and to consider the oncogenic implications of OBI. Proposals for future studies are identified, and the applicability of the recommendations in low-resource, high-endemic regions is considered, as well as the inclusion of OBI in global hepatitis elimination targets.

Surveillance Following Hepatitis B Surface Antigen Loss: An Issue Requiring Attention

Due to the lack of agents that directly target covalently closed circular DNA and integrated HBV DNA in hepatocytes, achieving a complete cure for chronic hepatitis B (CHB) remains challenging. The latest guidelines recommend (hepatitis B surface antigen) HBsAg loss as the ideal treatment target for improving liver function, histopathology, and long-term prognosis. However, even after HBsAg loss, hepatitis B virus can persist, with a risk of recurrence, reactivation, cirrhosis, and hepatocellular carcinoma. Therefore, follow-up and surveillance are still necessary. With increasing treatment options available for achieving HBsAg loss in patients with CHB, developing effective surveillance strategies has become crucial. Recent studies on outcomes following HBsAg loss provide new insights for refining current surveillance strategies, though further improvement is needed through long-term observation and follow-up.

Prediction of viral oncoproteins through the combination of generative adversarial networks and machine learning techniques

Viral oncoproteins play crucial roles in transforming normal cells into cancer cells, representing a significant factor in the etiology of various cancers. Traditionally, identifying these oncoproteins is both time-consuming and costly. With advancements in computational biology, bioinformatics tools based on machine learning have emerged as effective methods for predicting biological activities. Here, for the first time, we propose an innovative approach that combines Generative Adversarial Networks (GANs) with supervised learning methods to enhance the accuracy and generalizability of viral oncoprotein prediction. Our methodology evaluated multiple machine learning models, including Random Forest, Multilayer Perceptron, Light Gradient Boosting Machine, eXtreme Gradient Boosting, and Support Vector Machine. In ten-fold cross-validation on our training dataset, the GAN-enhanced Random Forest model demonstrated superior performance metrics: 0.976 accuracy, 0.976 F1 score, 0.977 precision, 0.976 sensitivity, and 1.0 AUC. During independent testing, this model achieved 0.982 accuracy, 0.982 F1 score, 0.982 precision, 0.982 sensitivity, and 1.0 AUC. These results establish our new tool, VirOncoTarget, accessible via a web application. We anticipate that VirOncoTarget will be a valuable resource for researchers, enabling rapid and reliable viral oncoprotein prediction and advancing our understanding of their role in cancer biology.

An overview of occult hepatitis B infection (OBI) with emphasis on HBV vaccination

Background

The prevalence of chronic hepatitis B virus (HBV) poses a significant threat to the lives of 257 million individuals globally, potentially resulting in severe outcomes such as liver cirrhosis or hepatocellular carcinoma. Among the existing preventive measures, yeast-derived vaccines have proven to be the most efficacious approach in combatting hepatitis B. Nonetheless, as scientific inquiries focus more on occult HBV infection (OBI) in vaccinated persons and the lingering risk of vertical transmission affecting 10-30 % of babies born to HBsAg-positive mothers, there is a growing apprehension regarding the inability of HBV vaccines to ensure complete immunity. This study aims to offer a more comprehensive understanding of the implications of widespread HBV vaccination initiatives on OBI while tackling the primary limitations associated with current vaccine formulations.

Methods

The exploration was conducted on PubMed, Scopus, and Web of Science databases to pinpoint research on OBI within vaccinated cohorts. A sum of 76 suitable studies was recognized.

Discussion

Multiple studies have documented the occurrence of OBI in fully vaccinated individuals, including both the general population and high-risk groups, such as newborns born to HBsAg-positive mothers. Factors contributing to vaccine failures include low-level anti-HBs antibodies, high maternal viral loads in mother-to-child transmission cases, as well as the presence of vaccine escape mutants and heterologous HBV genotypes. However, further research is needed to precisely understand the impact of active immunization on the emergence of OBI in vaccinated populations. Nonetheless, it is apparent that the advancement of more effective HBV vaccines could potentially lead to the extinction of HBV.

Occult Hepatitis B Virus Infection in Hepatic Diseases and Its Significance for the WHO's Elimination Plan of Viral Hepatitis

Liver damage can progress through different stages, resulting in cirrhosis or hepatocellular carcinoma (HCC), conditions that are often associated with viral infections. Globally, 42% and 21% of cirrhosis cases correlate with HBV and HCV, respectively. In the Americas, the prevalence ranges from 1% to 44%. The WHO has the goal to eliminate viral hepatitis, but it is important to consider occult HBV infection (OBI), a clinical condition characterized by the presence of HBV genomes despite negative surface antigen tests. This review aims to provide an overview of recent data on OBI, focusing on its role in the development of hepatic diseases and its significance in the WHO Viral Hepatitis Elimination Plan. Specific HBV gene mutations have been linked to HCC and other liver diseases. Factors related to the interactions between OBI and mutated viral proteins, which induce endoplasmic reticulum stress and oxidative DNA damage, and the potential role of HBV integration sites (such as the TERT promoter) have been identified in HCC/OBI patients. Health initiatives for OBI research in Latin American countries are crucial to achieving the WHO's goal of eradicating viral hepatitis by 2030, given the difficulty in diagnosing OBI and its unclear association with hepatic diseases.

The Role of Hepatitis Viruses as Drivers of Hepatocancerogenesis

Recently, metabolic associated steatotic liver disease (MASLD) became the leading cause of chronic liver disease worldwide and one of the most frequent causes of hepatocellular carcinoma (HCC). Nonetheless, in this epidemiological trend, viral hepatitis remains the major driver in hepatic carcinogenesis. Globally, hepatitis B virus (HBV) is the leading cause of hepatocellular carcinoma, with an overall attributable risk of approximately 40%, followed by hepatitis C virus (HCV), which accounts for 28-30% of cases, with significant geographic variations between the Eastern and Western world. Considering all the etiologies, HCC risk increases proportionally with the progression of liver disease, but the risk is consistently higher in patients with viral triggers. This evidence indicates that both direct (due to the oncogenic properties of the viruses) and indirect (through the mechanisms of chronic inflammation that lead to cirrhosis) mechanisms are involved, alongside the presence of co-factors contributing to liver damage (smoking, alcohol, and metabolic factors) that synergistically enhance the oncogenic process. The aim of this review is to analyze the oncogenic role of hepatitis viruses in the liver, evaluating epidemiological changes and direct and indirect viral mechanisms that lead to liver cancer.

Review of Related Factors for Persistent Risk of Hepatitis B Virus-Associated Hepatocellular Carcinoma

Chronic hepatitis B virus (HBV) infection is the largest global cause of hepatocellular carcinoma (HCC). Current HBV treatment options include pegylated interferon-alpha and nucleos(t)ide analogues (NAs), which have been shown to be effective in reducing HBV DNA levels to become undetectable. However, the literature has shown that some patients have persistent risk of developing HCC. The mechanism in which this occurs has not been fully elucidated. However, it has been discovered that HBV's covalently closed circular DNA (cccDNA) integrates into the critical HCC driver genes in hepatocytes upon initial infection; additionally, these are not targets of current NA therapies. Some studies suggest that HBV undergoes compartmentalization in peripheral blood mononuclear cells that serve as a sanctuary for replication during antiviral therapy. The aim of this review is to expand on how patients with HBV may develop HCC despite years of HBV viral suppression and carry worse prognosis than treatment-naive HBV patients who develop HCC. Furthermore, HCC recurrence after initial surgical or locoregional treatment in this setting may cause carcinogenic cells to behave more aggressively during treatment. Curative novel therapies which target the life cycle of HBV, modulate host immune response, and inhibit HBV RNA translation are being investigated.

Risk of HCC decreases in HBV-related patients with cirrhosis acquired recompensation: A retrospective study based on Baveno VII criteria

BACKGROUND

Antiviral therapy improves the clinical outcomes of patients with HBV-related cirrhosis. In this study, we aimed to evaluate the incidence rate of HCC in patients with HBV-related recompensated, compensated, or decompensated cirrhosis based on the latest Baveno VII criteria.

METHODS

In this two-center retrospective study, HBV-related patients with cirrhosis were enrolled and treated with first-line nucleos(t)ide analogues therapy for at least 12 months. Participants were classified into 3 groups: (1) compensated group, (2) decompensated group, or (3) recompensated group according to Baveno VII criteria. Multivariate regression models and propensity score matching were used to identify the predictors of HCC.

RESULTS

Of the 404 patients recruited, during a median follow-up of 44.5 months (interquartile range 26.8, 57.0 months), 233 (57.7%), 100 (24.8%), and 71(17.6%) patients had compensated, recompensated, and decompensated cirrhosis. In total, 38 developed HCC. The cumulative incidence of HCC development at 2, 4, and 6 years was 1.3%, 5.4%, and 20.0% in the compensated group, 1.2%, 5.2%, and 24.5% in the recompensated group, and 2.1%, 23.6%, and 41.8% in the decompensated group, respectively. In the multivariate Cox regression model, compared with the recompensated group, the decompensated group had a significant increased risk for the development of HCC (aHR 2.55; 95% CI: 1.240-5.240; p = 0.027), while the compensated group had similar HCC risk for the development of HCC (aHR 1.41; 95% CI: 0.540-3.730; p = 0.835). Propensity score-matching analysis between the recompensated and compensated groups (84 pairs) and propensity score-matching analysis between the recompensated and decompensated groups (62 pairs) showed similar results.

CONCLUSIONS

Achieving recompensation reduced the risk of HCC in patients with HBV-related decompensated cirrhosis, while the risk remained comparable to that of compensated cirrhosis.

Global prevalence of occult HBV infection in children and adolescents: A systematic review and meta-analysis

INTRODUCTION AND OBJECTIVES

Occult HBV infection (OBI) is a specific form of hepatitis B virus (HBV) infection and has the possibility of developing into hepatocellular carcinoma (HCC) in adults. This study aimed to estimate the global prevalence of occult HBV infection in children and adolescents.

MATERIALS AND METHODS

We systematically searched PubMed, Embase, Web of Science, and Cochrane databases for relevant studies on the prevalence of OBI in children and adolescents. Meta-analysis was performed using STATA 16 software.

RESULTS

Fifty studies were included. The overall prevalence of OBI in children and adolescents was 7.5% (95% CI: 0.050-0.103). In different risk populations, OBI prevalence was remarkably high in the HIV-infected population (24.2%, 95% CI: 0.000-0.788). The OBI prevalence was 0.8% (95% CI:0.000-0.029) in the healthy population, 3.8% (95% CI:0.012-0.074) in the general population, and 6.4% (95% CI: 0.021-0.124) in children born to HBsAg-positive mothers. Based on different serological profiles, the prevalence of OBI in HBsAg-negative and anti-HBc-positive patients was 6.6% (95% CI: 0.016-0.136), 3.0% (95% CI: 0.009-0.059) in HBsAg-negative and anti-HBc-negative patients, 4.6% (95% CI: 0.015-0.088) in HBsAg-negative and anti-HBs-positive patients, and 3.7% (95% CI: 0.001-0.102) in HBsAg-negative and anti-HBs-negative patients.

CONCLUSIONS

Despite HBV vaccination and hepatitis B immunoglobulin (HBIG), OBI is common in children and adolescents in high-risk groups.

Hepatitis Virus-associated Non-hodgkin Lymphoma: Pathogenesis and Treatment Strategies

Over the last decade, epidemiological studies have discovered a link between hepatitis C virus (HCV) and hepatitis B virus (HBV) infection and non-Hodgkin lymphoma (NHL). The regression of HCV-associated NHL after HCV eradication is the most compelling proof supporting HCV infection's role in lymphoproliferative diseases. HBV infection was found to significantly enhance the incidence of NHL, according to the epidemiological data. The exact mechanism of HCV leading to NHL has not been fully clarified, and there are mainly the following possible mechanisms: (1) Indirect mechanisms: stimulation of B lymphocytes by extracellular HCV and cytokines; (2) Direct mechanisms: oncogenic effects mediated by intracellular HCV proteins; (3) hit-and-run mechanism: permanent genetic B lymphocytes damage by the transitional entry of HCV. The specific role of HBV in the occurrence of NHL is still unclear, and the research on its mechanism is less extensively explored than HCV, and there are mainly the following possible mechanisms: (1) Indirect mechanisms: stimulation of B lymphocytes by extracellular HBV; (2) Direct mechanisms: oncogenic effects mediated by intracellular HBV DNA. In fact, it is reasonable to consider direct-acting antivirals (DAAs) as first-line therapy for indolent HCV-associated B-NHL patients who do not require immediate chemotherapy. Chemotherapy for NHL is affected by HBV infection and replication. At the same time, chemotherapy can also activate HBV replication. Following recent guidelines, all patients with HBsAg positive/HBV DNA≥2,000 IU/mL should be treated for HBV. The data on epidemiology, interventional studies, and molecular mechanisms of HCV and HBV-associated B-NHL are systematically summarized in this review.

The high prevalence of occult hepatitis B infections among the partners of chronically infected HBV blood donors emphasizes the potential residual risk to blood safety

A small percentage of couples who regularly donated blood in China tested positive for HBsAg. Although it is well known that blood donors can acquire hepatitis B virus (HBV) infection from a chronically infected sexual partner, the prevalence of occult hepatitis B infections (OBIs) among blood donations from partners of HBV-infected chronically infected spouses and the risk to blood safety remain poorly understood. Among 212 763 blood donors, 54 pairs of couples (108 donations) were enrolled because one partner tested positive for HBsAg. Several molecular and serological examinations were conducted. The origin of HBV transmission between sexual partners was investigated further. Also evaluated was the potential risk of HBV infection with OBIs. We identified 10 (10/54, 18.6%) sexual partners of chronically infected HBV donors who were positive for HBV DNA, including five samples (9.3%) with OBIs, of which 3 (3/54, 5.6%, 1 in 70 921 donations) passed the routine blood screening tests. Seven of the 10 HBV-DNA-positive couples contracted the virus possibly through sexual or close contact. Among infected couples, immune escape mutations were observed. A high prevalence of OBIs was found among the partners of chronically infected HBV blood donors, posing a potential threat to blood safety.

Positive hepatitis B core antibody is associated with advanced fibrosis and mortality in nonalcoholic fatty liver disease

OBJECTIVE

Concomitant hepatitis B virus infection and nonalcoholic fatty liver disease (NAFLD) are relatively common, while little is known about the impact of anti-hepatitis B core antibody (anti-HBc) on NAFLD individuals. We aimed to investigate the association of positive anti-HBc with advanced fibrosis and mortality in NAFLD.

METHODS

We analyzed data from 3268 NAFLD participants who underwent abdominal ultrasonography during the Third National Health and Nutrition Examination Survey (NHANES III). The fibrosis 4 index (FIB-4) score >2.67, NAFLD fibrosis score >0.676, or aspartate aminotransferase to platelet ratio index >1.5 were defined as advanced fibrosis. All-cause and cause-specific mortality were obtained from the NHANES III-linked follow-up file through 31 December 2015.

RESULTS

A total of 242 (7.4%) patients had positive anti-HBc. Patients with positive anti-HBc had a higher percentage of advanced fibrosis than those with negative anti-HBc (12.2% vs. 5.8%). Positive anti-HBc was significantly associated with advanced fibrosis [adjusted odds ratio = 1.69, 95% confidence interval (CI), 1.05-2.72]. During a median follow-up of 22 years, the cumulative all-cause and cancer-related mortalities were higher in participants with positive anti-HBc than in their counterparts (log-rank test P < 0.001). When demographic and metabolic risk factors were considered, NAFLD cases with positive anti-HBc had a significantly higher cancer-related mortality (adjusted hazard ratio = 1.54, 95% CI, 1.05-2.25).

CONCLUSION

Our findings suggested that NAFLD cases with positive anti-HBc had higher risks for liver fibrosis and long-term mortality, justifying the medical importance of testing anti-HBc in NAFLD patients.

Lamivudine 24-month-long prophylaxis is a safe and efficient choice for the prevention of hepatitis B virus reactivation in HBsAg-negative/HBcAb-positive patients with advanced DLBCL undergoing upfront R-CHOP-21

Introduction

Occult hepatitis B infection (OBI) is a condition where replication-competent hepatitis B virus-DNA (HBV-DNA) is present in the liver, with or without HBV-DNA in the blood [<200 international units (IU)/ml or absent] in HB surface antigen (HBsAg)-negative/HB core antibody (HBcAb)-positive individuals. In patients with advanced stage diffuse large B-cell lymphoma (DLBCL) undergoing 6 cycles of R-CHOP-21+2 additional R, OBI reactivation is a frequent and severe complication. There is no consensus among recent guidelines on whether a pre-emptive approach or primary antiviral prophylaxis is the best solution in this setting of patients. In addition, questions still unresolved are the type of prophylactic drug against HBV and adequate prophylaxis duration.

Methods

In this case-cohort study, we compared a prospective series of 31 HBsAg-/HBcAb+ patients with newly diagnosed high-risk DLBCL receiving lamivudine (LAM) prophylaxis 1 week before R-CHOP-21+2R until 18 months after (24-month LAM series) versus 96 HBsAg-/HBcAb+ patients (from January 2005 to December 2011) undergoing a pre-emptive approach (pre-emptive cohort) and versus 60 HBsAg-/HBcAb+ patients, from January 2012 to December 2017, receiving LAM prophylaxis [1 week before immunochemotherapy (ICHT) start until 6 months after] (12-month LAM cohort). Efficacy analysis focused primarily on ICHT disruption and secondarily on OBI reactivation and/or acute hepatitis.

Results

In the 24-month LAM series and in the 12-month LAM cohort, there were no episodes of ICHT disruption versus 7% in the pre-emptive cohort (P = 0.05). OBI reactivation did not occur in any of the 31 patients in the 24-month LAM series versus 7 out of 60 patients (10%) in the 12-month LAM cohort or 12 out of 96 (12%) patients in the pre-emptive cohort (P = 0.04, by χ ² test). No patients in the 24-month LAM series developed acute hepatitis compared with three in the 12-month LAM cohort and six in the pre-emptive cohort.

Discussion

This is the first study collecting data regarding a consistent and homogeneous large sample of 187 HBsAg-/HBcAb+ patients undergoing standard R-CHOP-21 for aggressive lymphoma. In our study, 24-month-long prophylaxis with LAM appears to be the most effective approach with a null risk of OBI reactivation, hepatitis flare-up, and ICHT disruption.

Characterization of occult hepatitis B infection among Iranian liver transplant recipients

BACKGROUND

The prevalence of occult hepatitis B infection (OBI) among Iranian liver transplant recipient patients has not been explored yet. The present study aimed to determine the OBI prevalence among Iranian liver transplant recipients.

METHODS

This study encompassed 97 patients having undergone liver transplantation due to several clinical backgrounds in the Liver Transplantation Center, Tehran, Iran. After serological evaluation, two different types of PCR methods were applied for amplification of HBV DNA, followed by the direct sequencing of whole hepatitis B virus (HBV) surface genes.

RESULTS

At the time of admission, none of the patients were positive for HBsAg. However, 24 (25%), 12 (12.3%), and 5 (5.1%) cases were positive for anti-HBc, hepatitis C virus (HCV), and hepatitis delta virus (HDV) antibodies, respectively. Moreover, two males were positive for OBI (2.1%). Both were positive for anti-HBc and negative for anti-HBs, anti-HCV, and anti-HDV. HBV-related cirrhosis was the underlying reason for their liver transplantation. HBsAg sequences revealed no amino acid substitution.

CONCLUSIONS

The prevalence of OBI in the Iranian liver transplantation patients was relatively low. Future longitudinal studies with a larger sample size are suggested to explore the significance of this clinical finding, including the reactivation of cryptic HBV DNA, in liver transplant subjects.

Antibody to hepatitis B virus core antigen positivity is a predictor of non-alcoholic fatty liver disease severity

Insufficient information is available about co-factors favoring the progression of non-alcoholic fatty liver disease (NAFLD) toward cirrhosis. We aimed to evaluate the impact of a limited alcohol intake and of occult hepatitis B virus (HBV) infection (OBI) on the severity of NAFLD. Three-hundred-seventy-four alcohol non-abusers and HBV surface antigen negative NAFLD patients (223 males; mean age 55.4 years), consecutively admitted to the outpatients clinic of a referral liver unit from January 1st, 2018 to December 31st, 2019, were studied. Anti-HBV core antigen antibody [(anti-HBc), a surrogate marker of OBI] was assessed in all patients. Patients were distinguished between teetotal and moderate alcohol consumers (intake of less than 30 g and 20 g if males or females, respectively). Liver fibrosis was non-invasively assessed by FIB-4 and transient elastography. Uni- and multivariate analyses were performed to identify predictors of advanced fibrosis. Patients had a mean BMI of 28.5 kg/m2, and the majority presented metabolic and cardio-vascular comorbidities [258 patients (69%) had insulin resistance/diabetes, 249 (66.6%) dyslipidemia, 200 (53.5%) arterial hypertension]. Multivariate analysis showed that anti-HBc positivity (p = 0.046, OR 2.153) was a factor associated with advanced fibrosis at FIB-4 score testing, whereas moderate alcohol intake was not associated with severe NAFLD both at FIB-4 and transient elastography evaluations. The study showed that a moderate alcohol intake has no impact on NAFLD severity and suggested that OBI might negatively affect the NAFLD outcome.

Comparison of S gene mutations in patients with occult and chronic hepatitis B virus infection

BACKGROUND AND AIM

This study aimed to detect mutations in the HBV S gene and evaluate their relationship to occult hepatitis B virus (HBV) infection (OBI).

METHODS

The study included 32 patients with negative serum HBsAg and HBV DNA who underwent liver biopsy due to different clinical indications defined as the OBI group and 32 patients who underwent liver biopsy due to chronic hepatitis B (CHB) as the comparison group. The HBV S gene region was amplified by Nested PCR, and Sanger sequencing was performed.

RESULTS

At least one amino acid (aa) mutation was detected in the major hydrophilic region (MHR) of the HBV S gene in 14/32 (43.75%) of the patients with OBI and 8/32 (25.0%) with CHB. The genotype of all patients with OBI and CHB was HBV/D. Although 9 (28.1%) of the cases with OBI had sub-genotype HBV/D3, none of the patients with CHB had sub-genotype HBV/D3. Unlike patients with CHB, L15*, D33N, Q51P, V63F, L91I, P108S, T115I, P120L, T125M, Q129H, T189I, L216F, P217L mutations were detected in the HBV S gene in OBI cases. Also, P127T aa polymorphism was frequently detected. Mutation frequency in the HBV S gene in the major hydrophilic region (MHR) was higher in patients with OBI with sub-genotypes HBV/D3 and D2 than those with HBV/D1 and those with serotype HBV/ayw3 compared to those with HBV/ayw2 (p < 0.05).

CONCLUSIONS

Sub-genotypic-specific mutation patterns were seen in the "a" determinant region and T helper cell epitopes of HBsAg, especially in the C-terminus domain; this may be associated with OBI.

Prevalence of occult hepatitis B infection in liver biopsy sample of patients with nonviral liver disease

Aim: To determine the prevalence of occult hepatitis B (HBV) infection (OBI) in patients with nonviral liver disease. Materials & methods: This study included 83 HBsAg-negative patients followed up at a gastroenterohepatology clinic. The presence of HBV DNA was investigated by using an in-house nested-PCR method applied to liver parenchymal biopsy samples obtained from patients who underwent due nonviral chronic liver disease. Results: OBI was detected in 19 (22.9%) of the 83 cases, in 11 (44%) of 25 anti-HBc-positive patients, and 15 (31.9%) of 47 anti-HBc and/or anti-HBs antibodies-positive patients. Conclusion: There is a considerable prevalence of OBI among patients with nonviral chronic liver disease. Therefore, it is suggested that closely monitoring HBV can be useful to prevent or more effectively manage possible OBI-related complications among patients with nonviral chronic liver disease, especially those who are HBsAg seronegative or anti-HBV antibody seropositive.

Occult Hepatitis B Virus Infection: An Update

Occult hepatitis B virus (HBV) infection (OBI) refers to a condition in which replication-competent viral DNA is present in the liver (with detectable or undetectable HBV DNA in the serum) of individuals testing negative for the HBV surface antigen (HBsAg). In this peculiar phase of HBV infection, the covalently closed circular DNA (cccDNA) is in a low state of replication. Many advances have been made in clarifying the mechanisms involved in such a suppression of viral activity, which seems to be mainly related to the host's immune control and epigenetic factors. OBI is diffused worldwide, but its prevalence is highly variable among patient populations. This depends on different geographic areas, risk factors for parenteral infections, and assays used for HBsAg and HBV DNA detection. OBI has an impact in several clinical contexts: (a) it can be transmitted, causing a classic form of hepatitis B, through blood transfusion or liver transplantation; (b) it may reactivate in the case of immunosuppression, leading to the possible development of even fulminant hepatitis; (c) it may accelerate the progression of chronic liver disease due to different causes toward cirrhosis; (d) it maintains the pro-oncogenic properties of the "overt" infection, favoring the development of hepatocellular carcinoma.

What is the clinical impact of occult HBV infections and anti-HBc positivity in patients with chronic hepatitis C?

Occult hepatitis B infection (OBI) is defined by the persistence of the hepatitis B virus (HBV) genome in the liver of individuals testing negative for hepatitis B surface antigen (HBsAg). Hepatitis B core antibody (anti-HBc) is the serological marker that indicates HBV exposure. The impact of anti-HBc and OBI on patients with chronic hepatitis C remains unclear. The aim of the present study was to determine the prevalence of anti-HBc and OBI and to evaluate their impact on the clinical and pathological outcomes of patients with chronic hepatitis C. The study included 59 HBsAg-negative chronic hepatitis C patients who underwent a liver parenchymal biopsy. The presence of HBV DNA was investigated using an in-house nested PCR method. OBI was detected in 16 (27.1%) of the 59 cases and also in 10 (62.5%) of 22 (37.3%) anti-HBc-positive patients. None of the patients had positive serum HBV DNA. OBI was associated with the presence of anti-HBV antibodies (p<0.05). There was also an association between anti-HBc positivity and the activity grades and fibrosis stages of the liver and also a prevalence of liver steatosis (p<0.05). Positive anti-HBc results may predict OBI and also be associated with the progression of liver injury in HBsAg-negative patients with chronic hepatitis C. Therefore, it is suggested that patients with chronic hepatitis C should be screened for anti-HBc positivity, and anti-HBc-positive patients should be carefully evaluated for disease progression. This article is protected by copyright. All rights reserved.

High-Frequency Notable HBV Mutations Identified in Blood Donors With Occult Hepatitis B Infection From Heyuan City of Southern China

Background

All Chinese blood centers have implemented mini pool (MP) HBV nucleic acid testing (NAT) together with HBsAg ELISA in routine donor screening since 2015. The prevalence of occult hepatitis B virus infection (OBI) in donors from different regions varies, and the molecular characterization of the HBV DNA and clinical outcomes of these OBIs remain largely unexplored.

Methods

Blood donations from Heyuan city in Southern China were screened by HBsAg ELISA and HBV MP8 NAT. Donations with HBsAg-/HBV DNA+ were collected for this study. Molecular characterizations of HBV DNAs were further analyzed by various DNA amplification assays including quantitative PCR (qPCR) and nested PCR, amplifying the basic core and pre-core promoter regions (BCP/PC). The HBsAg (S) region from HBV DNA was isolated by high-volume nucleic acid extraction. Notable mutations were identified by comparison to the HBV reference sequences. The clinical outcomes of the donors with OBIs were further followed for nearly 3 years.

Results

Seventy OBIs from 44,592 donations (0.15%) that we identified and reported previously were enrolled for this current study. HBV sequences were obtained from 44/70 OBIs, and genotyping analysis showed that 42/44 (95.2%) OBIs were genotype B, and 2/44 (4.8%) were genotype C. Interestingly, mutation analysis revealed that various mutations including M133L/T, F134L, P142L, V168A, R169H, S174N, L175S, and V177A of HBV DNA affecting HBsAg detection were observed in genotype B OBIs. Two notable mutations, T47K and L53S, were identified in genotype C OBIs. Follow-up studies showed that 3/31 (9.7%) OBIs converted to HBsAg+ as chronic infections while 1/31 (3.2%) HBV DNA was undetectable (classified as recovery) and 27/31 (87.1%) remained as OBIs.

Conclusion

Various notable mutations affecting HBsAg detection were observed in blood donors with OBIs in Heyuan city of Southern China. Follow-up studies showed that most OBIs remained as OBIs with fluctuating or low viral loads. Higher sensitive HBV ID NAT is recommended for donor screening to further reduce the transmission risk of OBIs.

Occult hepatitis B virus infection in hepatitis C virus negative chronic liver diseases

Data concerning the prevalence of hepatitis B virus (HBV) occult infection (OBI) varies greatly in the different studies according to the sensitivity and specificity of the diagnostic approaches and the HBV prevalence in the different populations examined. The clinical implications of OBI are still debated. While the impact of OBI in HBV transmission as well as in HBV reactivation under immunosuppression are well established, the role of OBI in liver disease and hepatocellular carcinoma (HCC) development are still not definitively elucidated. It has been hypothesized that OBI might contribute to worsening the liver disease course when other causes of liver damage co-exist. Furthermore, much evidence suggests a role of OBI in the hepato-carcinogenesis processes through both indirect and direct oncogenic mechanisms that might favour HCC development. Data on the OBI clinical implications mainly come from studies performed in patients with hepatitis C virus (HCV) infection. However, HCV prevalence has dramatically fallen in the past years also because of the advent of specific and highly effective direct acting antivirals, with a consequent abrupt change of the worldwide scenario of chronic liver disease. Information about OBI prevalence and possible clinical impact in non-HCV-related liver disease are fragmentary, and the objective of this review is to critically summarize the available data in this field.

Occult hepatitis B virus infection in patients with chronic liver disease of different etiology in a Brazilian referral center: comparison of two different hepatitis B virus deoxyribonucleic acid amplification protocols: a cross-sectional study

BACKGROUND

Occult hepatitis B virus infection (OBI) is defined as the presence of hepatitis B virus (HBV) deoxyribonucleic acid (DNA) in the liver of individuals with undetectable hepatitis B virus surface antigen (HBsAg) in the serum. The actual prevalence of OBI and its clinical relevance are not yet fully understood.

OBJECTIVE

To evaluate the prevalence of HBV DNA in liver biopsies of HBsAg-negative patients with chronic liver disease of different etiologies in a referral center in Brazil and compare two different HBV DNA amplification protocols to detect HBV.

DESIGN AND SETTING

This cross-sectional observational study was conducted at the Liver Outpatient Clinic, Hospital das Clínicas, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil, between January 2016 and December 2019.

METHODS

HBV DNA was investigated in 104 liver biopsy samples from individuals with chronic liver disease of different etiologies, in whom HBsAg was undetectable in serum by nested-polymerase chain reaction (nested-PCR), using two different protocols.

RESULTS

OBI, diagnosed by detecting HBV DNA using both protocols, was detected in 6.7% of the 104 individuals investigated. Both protocols showed a good reliability.

CONCLUSION

In addition to the differences in the prevalence of HBV infection in different regions, variations in the polymerase chain reaction technique used for HBV DNA amplification may be responsible for the large variations in the prevalence of OBI identified in different studies. There is a need for better standardization of the diagnostic methods used to diagnose this entity.

In silico analysis of mutations associated with occult hepatitis B virus (HBV) infection in South Africa

Occult hepatitis B virus (OBI) infection is defined by the presence of viral DNA in the liver and/or serum in absence of hepatitis B surface antigen (HBsAg). While multiple studies have identified mutations that are associated with OBI, only a small portion of these mutations have been functionally characterized in vitro. Using complementary in silico approaches, the effects of OBI-associated amino acid mutations on HBV protein function in HBV/HIV-positive ART-naïve South Africans were evaluated. Two OBI-associated mutations in the PreS1 region, one in the PreS2 region, and seven in the surface region of subgenotype A1 sequences were identified as deleterious. In subgenotype A2 sequences, 11 OBI-associated mutations in the PreS1 region, seven in the PreS2 region, and 31 in the surface region were identified as deleterious. In the polymerase region, 14 OBI-associated mutations in subgenotype A1 and 71 OBI-associated mutations in subgenotype A2 were identified as deleterious. This study utilized in silico approaches to characterize the likely impact of OBI-associated mutations on viral function, thereby identifying and prioritizing candidates and reducing the significant cost associated with functional studies that are essential for mechanistic studies of the OBI phenotype.

Long-term Survival of 10,116 Korean Live Liver Donors

OBJECTIVE

To evaluate the long-term mortality of Korean live liver donors using data from a national donor registry by comparing it with the mortality of the general population.

SUMMARY OF BACKGROUND DATA

Although live liver donors generally have a healthy status, their long-term mortality has not been properly addressed in a large donor registry.

METHODS

Data of 10,116 live liver donors were drawn from a mandated national registry of Korean live liver donors between 2000 and 2015. Matched controls were selected from the Korean National Health Insurance System-National Sample Cohort (NHIS-NSC). Median (range) follow-up of liver donors was 5.7 (0-15.9) years. Donors were 1:3 individually matched to controls by sex and 5-year age group; potential controls were from the whole NHIS-NSC (Control 1) or from NHIS-NSC after excluding people with contraindications to be organ donors (Control 2) (donor, n = 7538; Control 1, n = 28,248; Control 2, n = 28,248).

RESULTS

Fifty-three deaths occurred after donation. Ten-year cumulative mortality of live liver donors was 0.9%. The most common cause of death was suicide (n = 19) followed by cancer (n = 9) and traffic accident (n = 7). In the matched control analysis, overall risk of death was significantly lower in donors than in Control 1 (P < 0.001), but higher than in Control 2 (P < 0.001).

CONCLUSIONS

Liver donors have increased long-term mortality risk compared to similar healthy controls without contraindications to be organ donors. Therefore, long-term follow-up, including psychosocial support, is needed for live liver donors.

High Frequency Occult Hepatitis B Virus Infection Detected in Non-Resolved Donations Suggests the Requirement of Anti-HBc Test in Blood Donors in Southern China

Background

Most Chinese Blood Centers adopted mini pool (MP) nucleic acid testing (NAT) for HBV screening due to high cost of Individual donation (ID) NAT, and different proportions of MP-reactive but ID-non-reactive donations (MP+/ID-, defined as non-resolved donations) have been observed during daily donor screening process. Some of these non-resolved donations are occult HBV infections (OBIs), which pose potential risk of HBV transmission if they are not deferred. This study is aimed to further analyze these non-resolved donations.

Methods

The non-resolved plasma samples were further analyzed by serological tests and various HBV DNA amplification assays including quantitative PCR (qPCR) and nested PCR amplifying the basic core and pre-core promoter regions (BCP/PC; 295 base pairs) and HBsAg (S) region (496 base pairs). Molecular characterizations of HBV DNA+ non-resolved samples were determined by sequencing analysis.

Results

Of 17,226 MPs from 103,356 seronegative blood donations, 98 MPs were detected reactive for HBV. Fifty-six out of these 98 (57.1%) reactive MPs were resolved as HBV DNA+, but the remaining 42 pools (42.9%, 252 donations) were left non-resolved with a high rate (53.2%) of anti-HBc+. Surprisingly, among 42 non-resolved MPs, 17 contained one donation identified as OBIs by alternative NAT assays. Sequence analysis on HBV DNAs extracted from these OBI donations showed some key mutations in the S region that may lead to failure in HBsAg detection and vaccine escape.

Conclusion

A total of 53.2% of the non-resolved donations were anti-HBc+, and OBIs were identified in 40.5% of these non-resolved pools. Therefore, non-resolved donations with anti-HBc+ might pose potential risk for HBV transmission. Our present analysis indicates that anti-HBc testing in non-resolved donations should be used to identify OBIs in order to further increase blood safety in China.

Update on the association of hepatitis B with intrahepatic cholangiocarcinoma: Is there new evidence?

Intrahepatic cholangiocarcinoma (iCCA) is a subgroup of cholangiocarcinoma that accounts for about 10%-20% of the total cases. Infection with hepatitis B virus (HBV) is one of the most important predisposing factors leading to the formation of iCCA. It has been recently estimated based on abundant epidemiological data that the association between HBV infection and iCCA is strong with an odds ratio of about 4.5. The HBV-associated mechanisms that lead to iCCA are under intense investigation. The diagnosis of iCCA in the context of chronic liver disease is challenging and often requires histological confirmation to distinguish from hepatocellular carcinoma. It is currently unclear whether antiviral treatment for HBV can decrease the incidence of iCCA. In terms of management, surgical resection remains the mainstay of treatment. There is a need for effective treatment modalities beyond resection in both first- and second-line treatment. In this review, we summarize the epidemiological evidence that links the two entities, discuss the pathogenesis of HBV-associated iCCA, and present the available data on the diagnosis and management of this cancer.

Clinical and survival outcomes after hepatectomy in patients with non-alcoholic fatty liver and hepatitis B-related hepatocellular carcinoma

BACKGROUND

The prevalence of non-alcoholic fatty liver disease-related hepatocellular carcinoma (NAFLD-HCC) has increased parallelly with that of metabolic syndrome. This study aimed to compare the clinical and survival outcomes of NAFLD-HCC and HBV-related HCC(HBV-HCC).

METHODS

The medical records of patients who underwent hepatectomy for HCC at Severance Hospital between 2005 and 2015 were retrospectively reviewed. Occult HBV infection was identified by nested PCR. Propensity score matching (PSM) was conducted to minimize lead-time bias caused by the lack of surveillance in NAFLD patients. Surgical and oncologic outcomes were compared between the two groups.

RESULTS

There were 32 patients (7%) with NAFLD-HCC, 200 (46%) with HBV-HCC, and 194 (44%) with HBV/NAFLD-HCC (HBV and NAFLD). Before PSM, cirrhosis was more frequently detected in HBV-HCC patients (55% vs 15%, p < 0.001) and the average tumor size was larger in the NAFLD-HCC group than in the HBV-HCC group (4.4 ± 3.3 cm vs 3.4 ± 1.8 cm, p = 0.014). After a median follow-up of 74 months (range 0-157 months), survival analyses before PSM showed better 5-year overall survival (OS) in HBV-HCC patients than in NAFLD-HCC patients (80% vs 63%, p = 0.041). After PSM, 5-year OS rates were similar (60% vs 63%, p = 0.978). There were no differences between the groups in recurrence-free or disease-specific survival before and after PSM.

CONCLUSION

Patients with NAFLD-HCC were less likely to have underlying cirrhosis but more likely to have larger tumors at the time of diagnosis than patients with HBV-HCC. The OS of patients with NAFLD-HCC appeared to be worse than that of patients with HBV-HCC. Therefore, active HCC surveillance is recommended in patients with metabolic syndrome for the early detection of HCC.

Reduction of the occurrence of occult HBV infection in infants by increasing the dose of hepatitis B vaccine: a large prospective cohort study

Occult hepatitis B virus (HBV) infection (OBI) has been observed among infants born to hepatitis B surface antigen (HBsAg)-positive mothers despite successful immunoprophylaxis. This study enrolled 549 infants [349 infants received a 10μg/dose of hepatitis B vaccine (HepB), and 200 infants received 20μg/dose HepB] born to HBsAg-positive mothers with HBV DNA load >6log₁₀IU/mL. The anti-HBs levels in the 10μg group were significantly lower than that in the 20μg group both at 7 [652.48 (564.05-754.82) vs. 1541.72 (1268.69-1873.51) mIU/mL, P<0.001] and 12 months old [257.44 (220.29-300.88) vs. 1073.41 (839.27-1372.78) mIU/mL, P<0.001]. The OBI incidence in the 10μg group was significantly higher than that in the 20μg group at both 7 [21.55% (25/116) vs. 7.56% (9/119), P=0.002] and 12 months old [17.07% (14/82) vs. 6.90% (6/87), P=0.041]. OBI incidence in infants with anti-HBs levels <100mIU/mL was higher than that of those with anti-HBs ≥100mIU/mL [35.71% (5/14) vs. 13.12% (29/221), P=0.036]. This study showed that increasing the immunisation dose from 10μg to 20μg significantly improved anti-HBs levels and decreased OBI incidence in infants with a high maternal viral load. We recommend 20μg HepB to treat this high-risk population.

Hepatocellular carcinoma risk in patients with HBV-related liver disease receiving antiviral therapy

Hepatitis B virus (HBV) is a major health problem worldwide, with approximatively 240 million people living with a chronic HBV infection. HBV chronic infection remains the major cause of hepatocellular carcinoma worldwide, with more than half of HCC patients being chronic HBV carriers, even if underlying mechanisms of tumorigenesis are not totally understood. HBV-related HCC can be prevented by reducing the exposure to HBV by vaccination or by treatment of CHB infection. Current treatment of CHB are Peg-IFN alpha and oral NUCs. Treating HBV infection, either with IFN or NUCs, substantially reduces the risk of HCC development, even if antiviral therapy fails to completely eliminate HCC risk. Among treated patients, cirrhosis, HBeAg negative at baseline and failure to remain in virological remission were associated with an increased risk of HCC. The reduction of the risk of developing HCC during antiviral therapy is largely dependent upon the maintenance of virological remission, since viral load is found to be the most important factor leading to cirrhosis and its complications, including liver cancer development. The question whether Peg-IFN-alpha is superior to NUCs and whether there is a superior agent among NUCs is still controversial. Several studies demonstrated that antiviral therapy with NUCs could reduce the risk of HCC recurrence after curative treatment of HBV-related HCC.

Characterization of Occult Hepatitis B Virus Infection Among Iranian Patients with Behcet's Disease; Correlation with Clinical Status

Background: Behcet's disease (BD) is a chronic multisystem vasculitis with an unknown etiology. During the past years, several reports are published on the occult hepatitis B infection (OBI), the presence of hepatitis B virus (HBV) DNA in the absence of HBsAg, in rheumatic diseases. Objectives: The current study aimed to, firstly, investigate the prevalence of OBI in patients with BD, and, secondly, its potential association with the clinical and therapeutic status of BD. Methods: HBV serological markers and HBV DNA were evaluated in 220 consecutive BD patients to detect OBI. Demographic and clinical data of OBI positive and negative groups were compared. Results: The mean age of patients was 39.24 (± 10.57), and 134 (62.9%) were male. The mean disease duration was 14.13 (± 8.63) years. No HBsAg positive case was found, but HBV DNA was found in 19 (8.6%) patients. The median viral load value was 475.84 copy/mL. We compared clinical data of 10 OBI positive and 156 OBI negative BD patients with complete and accessible data. There was no difference between the two groups concerning demographic characteristics (age, sex, and disease duration), different clinical manifestations, or types of medications (immunomodulatory, cytotoxic, and corticosteroids). Conclusions: This is the first study showing a rather high prevalence of OBI among BD patients. We did not find any correlation between OBI positivity and different clinical manifestations, medications, or HLA-B51. Further studies are needed on a larger group of patients and by molecular HBV evaluation (as well as serologic) regarding this possible association.

Method for detecting hepatitis B virus in blood plasma at low viral load using real-time PCR

A method for detecting HBV DNA in peripheral blood at low viral load using real-time PCR was developed and its significance in identifying HBsAg-negative viral hepatitis B was evaluated. When developing the method, blood plasma samples and liver tissue biopsy material were used from 128 patients living in St. Petersburg, in various regions of the Russian Federation, as well as in the Central Asia countries. We also used blood plasma samples from 96 pregnant women and 37 hemodialysis center patients living in Northwestern Federal District, 199 foreign citizens undergoing medical examination to obtain work permits at the Directorate for Migration in the Northwestern Federal District, 397 conditionally healthy people living in the Socialist Republic of Vietnam. HBV was detected by nested PCR. Analytical sensitivity was tested using the stepwise dilution method. According to the method developed by us, at the first stage, the HBV DNA is amplified using at the first stage oligonucleotides flanking the genome region 2932-3182 ... 1-1846 nt., and at the second stage two oligonucleotides pairs to the genome virus regions (gene S and gene X) and corresponding oligonucleotide fluorescently labeled probes complementary to the amplified fragments regions carrying fluorophores at the 5'-end, and non-fluorescent quenchers at the 3'-end. The channel corresponding to the FAM fluorophore detects the HBV DNA S-region amplification product, and the channel corresponding to the ROX fluorophore detects the HBV DNA X-region amplification product. The method sensitivity for DNA extraction from plasma with a 100 μl volume was 10 IU/ml. Obtaining a threshold cycle Ct for only one FAM or ROX fluorophore may indicate the HBV DNA presence in a sample at a load of less than 10 IU / ml, HBV detection in this case is possible with a repeated PCR study of the corresponding sample with HBV DNA extraction from an increased plasma volume (200-1000 μl). The developed method makes it possible to identify various HBV genovariants, both characteristic and rare in the Russian Federation, circulating in other world regions. The method can be used to detect HBV in risk groups, in the population, as well as in screening blood donors in order to ensure the blood transfusions safety.

Persistence of intrahepatic hepatitis B virus DNA integration in patients developing hepatocellular carcinoma after hepatitis B surface antigen seroclearance

BACKGROUND/AIMS

The role of hepatitis B virus (HBV) integration into the host genome in hepatocarcinogenesis following hepatitis B surface antigen (HBsAg) seroclearance remains unknown. Our study aimed to investigate and characterize HBV integration events in chronic hepatitis B (CHB) patients who developed hepatocellular carcinoma (HCC) after HBsAg seroclearance.

METHODS

Using probe-based HBV capturing followed by next-generation sequencing technology, HBV integration was examined in 10 samples (seven tumors and three non-tumor tissues) from seven chronic carriers who developed HCC after HBsAg loss. Genomic locations and patterns of HBV integration were investigated.

RESULTS

HBV integration was observed in six patients (85.7%) and eight (80.0%) of 10 tested samples. HBV integration breakpoints were detected in all of the non-tumor (3/3, 100%) and five of the seven (71.4%) tumor samples, with an average number of breakpoints of 4.00 and 2.43, respectively. Despite the lower total number of tumoral integration breakpoints, HBV integration sites in the tumors were more enriched within the genic area. In contrast, non-tumor tissues more often showed intergenic integration. Regarding functions of the affected genes, tumoral genes with HBV integration were mostly associated with carcinogenesis. At enrollment, patients who did not remain under regular HCC surveillance after HBsAg seroclearance had a large HCC, while those on regular surveillance had a small HCC.

CONCLUSION

The biological functions of HBV integration are almost comparable between HBsAg-positive and HBsAgserocleared HCCs, with continuing pro-oncogenic effects of HBV integration. Thus, ongoing HCC surveillance and clinical management should continue even after HBsAg seroclearance in patients with CHB.

Prevalence of occult HBV infection in Western countries

Due to a lack of standardized tests, it is difficult to obtain prevalence data and define the real impact of occult HBV infection (OBI) in Western countries. The present review article addresses the prevalence of OBI, defined as presence of hepatitis B virus (HBV) DNA in liver tissue or plasma in HBsAg-negative subjects, in Western countries. This varies in different studies according to the different methodologies used (based on serology vs virology), to the sample analyzed for the diagnosis (liver tissue vs plasma), to the different populations studied, to the different geographical variations in the HBV spread, to the host characteristics (age, gender, risk factors for acquiring HBV infection) and to the presence of other parenteral infections (hepatitis C virus and/or human immunodeficiency virus [HIV] infections). Considering the different liver diseases analyzed, that is in patients with cryptogenic cirrhosis or advanced liver fibrosis, the prevalence of OBI ranges 4% to 38%. Considering the different populations studied, in the case of parenteral blood exposure it is about 45%, in patients with chronic hepatitis C it is estimated at about 52%, in HIV-infected patients it ranges from 0% to 45%, in blood donors from 0% to 22.7% and in hemodialysis patients it ranges from 0% to 54%. In conclusion, OBI is a virological entity to be considered when performing the patient's evaluation for immunosuppressive diseases, liver pathologies, or for blood transfusions. Knowing the prevalence and clinical impact of OBI will allow better patient management.

Occult hepatitis B infection and hepatocellular carcinoma: Epidemiology, virology, hepatocarcinogenesis and clinical significance

Occult hepatitis B infection (OBI) refers to a condition where replication-competent HBV DNA is present in the liver, with or without HBV DNA in the blood, in individuals with serum HBsAg negativity assessed by currently available assays. The episomal covalently closed circular DNA (cccDNA) in OBI is in a low replicative state. Viral gene expression is mediated by epigenetic control of HBV transcription, including the HBV CpG island methylation pathway and post-translational modification of cccDNA-bound histone, with a different pattern from patients with chronic HBV infection. The prevalence of OBI varies tremendously across patient populations owing to numerous factors, such as geographic location, assay characteristics, host immune response, coinfection with other viruses, and vaccination status. Apart from the risk of viral reactivation upon immunosuppression and the risk of transmission of HBV, OBI has been implicated in hepatocellular carcinoma (HCC) development in patients with chronic HCV infection, those with cryptogenic or known liver disease, and in patients with HBsAg seroclearance after chronic HBV infection. An increasing number of prospective studies and meta-analyses have reported a higher incidence of HCC in patients with HCV and OBI, as well as more advanced tumour histological grades and earlier age of HCC diagnosis, compared with patients without OBI. The proposed pathogenetic mechanisms of OBI-related HCC include the influence of HBV DNA integration on the hepatocyte cell cycle, the production of pro-oncogenic proteins (HBx protein and mutated surface proteins), and persistent low-grade necroinflammation (contributing to the development of fibrosis and cirrhosis). There remain uncertainties about exactly how, and in what order, these mechanisms drive the development of tumours in patients with OBI.

Occult hepatitis B virus infection predicts non-alcoholic steatohepatitis in severely obese individuals from Italy

BACKGROUND & AIMS

Obesity is associated with non-alcoholic fatty liver (NAFL), which may progress towards non-alcoholic steatohepatitis (NASH), cirrhosis and hepatocellular carcinoma (HCC). Occult hepatitis B virus infection (OBI) may contribute to hepatic damage in patients with chronic liver disease of different aetiologies (eg HCV, alcohol). However, information on the prevalence and clinical impact of OBI in obese individuals is lacking. The aims of this study were to investigate NASH prevalence and risk factors in obese people who underwent bariatric surgery.

METHODS

Two-hundred and twenty-six subjects (160 females; mean age 42.9 years ±10.8 SD) without evidence of any further cause of liver disease consecutively underwent bariatric surgery in two Italian liver centers. During surgery, all patients underwent liver biopsy for histological evaluation and molecular studies. Liver DNA extracts were tested for PNPLA3, TM6SF2, MBOAT7, IRGM polymorphisms and for OBI. Univariate and multivariate analyses were used to identify predictors of NASH.

RESULTS

Histology showed NASH in 115 (50.9%) and NAFL in 111 cases (49.1%). Twenty-nine/226 (12.8%) cases had OBI, 24 (82.8%) of whom had NASH and 5 (17.2%) NAFL, whereas among the 197 OBI-negative cases, 91 (46.2%) had NASH and 106 (53.8%) NAFL (P = .0002). Multivariate analysis showed that older age (P = .03, OR 1.034), alanine aminotransferase values (P = .005, OR 1.023), insulin resistance/diabetes (P = .02, OR 2.257), TM6SF2 polymorphism (P = .04, OR 3.168) and OBI (P = .004, OR 5.503) were independent predictors of NASH.

CONCLUSION

NASH is highly prevalent in obese individuals undergoing bariatric surgery. OBI is one of the strongest risk factors of NASH in these patients.

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.

An estimation of the prevalence of occult HBV infection in Western Europe and in Northern America: A meta-analysis

Data on the prevalence of occult HBV infection (OBI) in Western Europe and in Northern America are few; hence, we conducted a systematic review and meta-analysis. All studies included had to fulfil the following inclusion criteria: (a) they investigated the prevalence of OBI (HBV DNA in liver tissue in HBsAg-negative subjects), (b) were carried out in Western Europe and in Northern America; (c) were available as a full-text manuscript, (d) written in English and (e) published up to December 2018. The exclusion criteria were as follows: (a) meta-analyses, letters, reviews, meeting abstracts or editorial comments; (b) studies investigating HBsAg-positive patients; (c) those investigating OBI outside Western Europe and in Northern America; and (d) to avoid small sample bias in the random-effects model, those enrolling less than five subjects. Thirty-four studies met the inclusion criteria, allowing a meta-analysis on 2729 patients. The overall prevalence of OBI was 34% (95% CI = 26%-42%), 28% (CI 95%: 12%-48%) in 329 subjects without chronic liver disease and 35% (95% CI 26%-44%) in 2400 patients with chronic liver disease. The prevalence of OBI was 51% (95% CI 40%-62%) in the 823 anti-HBc-positive subjects and 19% (95% CI 10%-30%) in the 1,041 anti-HBc-negative subjects. Evaluating the data from 17 studies comparing anti-HBc-positive and negative subjects, the prevalence of OBI was higher in the 641 anti-HBc-positive subjects than in the 1041 anti-HBc-negative (prevalence ratio = 2.29; 95% CI = 1.61-3.26, P < .001). This meta-analysis showed that in HBsAg-negative subjects the prevalence of OBI was high and was associated with anti-HBc positivity.

Potential etiology, prevalence of cirrhosis, and mode of detection among patients with non-B non-C hepatocellular carcinoma in Korea

BACKGROUND/AIMS

We systematically evaluated the clinical characteristics, prevalence of cirrhosis, and mode of detection in virus-unrelated (non-B non-C, NBNC) hepatocellular carcinoma (HCC) patients in Korea.

METHODS

A total of 447 consecutive treatment-naïve NBNC-HCC adult patients who were registered at the Samsung Medical Center HCC registry in Korea from 2010 to 2013 were analyzed. NBNC was defined as negative hepatitis B surface antigen and negative anti-hepatitis C virus antibody. Presence of cirrhosis was determined based on histological, radiological, endoscopic, and serologic results. Mode of detection was classified as either under surveillance, incidental, or symptomatic.

RESULTS

Heavy alcohol use was the most common potential etiology in NBNCHCC (NBNC-A, alcohol) (59.7%). Ten patients had other identifiable causes (NBNC-O, other identifiable cause) such as autoimmune hepatitis. The rest (38.0%) had no-identifiable cause (NBNC-NA-NO, non-alcohol, no-other identifiable cause). In NBNC-NA-NO group, 83.5% (96/115) of patients with available hepatitis B core immunoglobulin G antibody (HBcIgG) showed HBcIgG positivity, and 80.6% (137/170) had metabolic risk factors (diabetes, obesity, hypertension, and/ or dyslipidemia). Cirrhosis was present in 90.0%, 70.4%, and 60.0% of NBNC-O, NBNC-A, and NBNC-NA-NO patients, respectively. The proportion of patients diagnosed under surveillance was 25.5% across all patients, with specific proportions being 80.0%, 27.7%, and 18.8% for NBNC-O, NBNC-A, and NBNC-NA-NO, respectively.

CONCLUSION

Among NBNC-HCC patients, heavy alcohol use or any other identifiable cause was not found in 38.0%. These NBNC-NA-NO HCC patients showed a high prevalence of HBcIgG positivity and metabolic risk factors, suggesting that prior hepatitis B virus infection and metabolic risk factors may be major contributing factors in the hepatocarcinogenesis in NBNC-NA-NO patients.

[Hepatitis B virus identification in a blood plasma at a low viral load.]

To analyze the method for detecting HBV DNA in peripheral blood at low viral load and evaluate its significance in identifying HBsAg-negative viral hepatitis B. In this work, samples of blood and liver tissue biopsy material were used from 128 patients living in the Russian Federation and the Republic of Uzbekistan without CHB and with CHB confirmed detection of circle covalently closed HBV DNA in hepatocytes. Plasma viral load was measured using the «AmpliSens® HBV-Monitor-FL» kit. HBV at low viral load was detected by nested PCR. Analytical sensitivity was checked by step dilution. According to our method, at the first stage, an asymmetric PCR is carried out using extended oligonucleotide primers with different melting points, complementary to the hepatitis B different genotypes genomes greatest similarity region. To increase the sensitivity, a second PCR is performed using the first reaction amplification product and internal primers. The sensitivity of the method for DNA extraction from 100 μl of plasma was 5 IU / ml, specificity 100%. Since, in spite of the HBV genotypes characteristic geographical distribution, the detection of "alien" genovariants for certain territories is becoming more frequent, we tested the method in geographically remote but active international relations with the Russian Federation regions with a high frequency of hepatotropic viruses. The developed method for detecting HBV DNA in blood plasma at low viral load based on PCR technology allows the various HBV gene variants identification and genotyping, both characteristic and rare in the Russian Federation, circulating in other world regions. The method can be used to detect HBV in risk groups, in a population, as well as when screening blood donors in order to ensure the blood transfusions safety.

[The quantitative determination method of covalently closed circular DNA HBV in puncture biopsy specimens of the liver.]

To analyze the method HBV covalent-closed circular DNA quantitative determination in liver puncture biopsies and evaluate its significance in identifying HBsAg-negative viral hepatitis B. In this work, samples of liver tissue biopsy material were used from 128 patients living in St. Petersburg, in various regions of the Russian Federation, as well as in the Republic of Uzbekistan. For quantitative analysis of HBV covalently closed circular DNA in a biopsy material a method was developed based on real-time PCR using TaqMan probes for the target fragment and for the endogenous reference gene, based on the detecting ccc HBV DNA method of Pollicino T. et al. When quantifying ccc DNA HBV in liver tissue of 18 moderately HBV activity with HBV DNA PCR positive results patients and 16 inactive HBsAg carriers, the ccc DNA HBV content was significantly different between groups (p<0.034) and in terms 1 copy of the β-globin gene among moderate activity HBV patients amounted to 1.71±1.32 copies/cell, and for inactive HBsAg carriers 0.15±0.14 copies/cell. In the group of patients with severe liver fibrosis and cirrhosis, the amount of ccc DNA HBV in liver tissue in patients with HBV averaged 2.5±0.4 copies/cell, in patients with HBV + D on average 0.7±0.25 copies/cell, in patients with HCV + HBV co-infection 0.45±0.07 copies/cell, in patients with a preliminary diagnosis of chronic hepatitis C hepatitis, on average 0.12±0.04 copies/cell, in patients with cryptogenic hepatitis 0.2± 0.05 copies/cell. A significant difference was shown between the group of patients with chronic hepatitis B with marked fibrosis and cirrhosis of the liver with other patients groups, except for the group of 18 moderate activity chronic hepatitis B patients. The values of Student's t-test when compared with other groups were respectively: for patients with a HCV preliminary diagnosis t=5,92 p<0,05 f = 19, patients with cryptogenic hepatitis t=5,71 p<0,05 f = 18, with «inactive HBsAg carriage» t=5,55 p<0,05 f = 29, with HCV + HBV co-infection t=5,05 p<0,05 f = 15 and HBV + D co-infection t=3,82 p<0,05 f = 17. The covalently closed circular DNA HBV quantitative assessment method in liver puncture biopsies allows identifying HBsAgnegative chronic viral hepatitis B forms and also reflects the virus replication activity, which, in turn, makes it possible to assume further disease progression and evaluate the antiviral therapy effectiveness.

Increased liver injury in patients with chronic hepatitis and IgG directed against hepatitis E virus

Type-E hepatitis is responsible for more than three million symptomatic cases and more than 40,000 deaths worldwide. The situation of this hepatitis is overall poorly known in sub-Saharan Africa. Notably, the baseline circulation of HEV outside sporadic outbreaks has been barely characterized in this large region. More specifically, the impact of superinfection by this virus on the health status of the large reservoir of patients chronically infected with other hepatitis viruses remains to be evaluated. We searched for anti-HEV immunoglobulins in a series of 200 pregnant women and 92 patients with persistent liver infections with hepatitis B or C viruses and subsequently tried to assess serological co-variations with demographical and clinical features. We observed that only 1.5 % of expectant mothers were seropositive of anti-HEV IgG while it was the case for 18.4 % of patients with chronic liver diseases (P=4.5E-07). The presence of anti-HEV was not linked to any of the collected demographical features (age, sex, education, pork meat consumption, water supply, …). By contrast, the presence of anti-HEV was significantly associated with increased levels (1.6-1.8-fold, P<0.0001) of blood aminotransferases (AST, ALT) in patients with persistent hepatitis B or C. Our work indicates that, in Ivory Coast, the presence of IgG directed against HEV might contribute to a deterioration of liver health in patients with already installed persistent liver infections. The mechanisms explaining such phenomenon at distance of acute phase of infection are still unknown but might be linked either to a residual persistence of HEV in a context of general immune exhaustion or to an inappropriate auto-immune reaction as already observed in the aftermath of other viral infection types.

Pro-oncogenic, intra host viral quasispecies in Diffuse large B cell lymphoma patients with occult Hepatitis B Virus infection

Non Hodgkin lymphoma, predominantly Diffuse Large B-cell Lymphoma (DLBCL) has been reported to have a significant association with Hepatitis B virus (HBV). We investigated the presence of different gene segments of HBV in plasma, B-cells and tumor tissues from DLBCL patients and explored the genetic variability of HBV within and across different compartments in a host using Next Generation Sequencing. Despite all 40 patients being HBV seronegative, 68% showed evidence of occult HBV. Sequencing of these gene segments revealed inter-compartment viral variants in 26% of them, each with at least one non-synonymous mutation. Between compartments, core gene variants revealed Arg94Leu, Glu86Arg and Ser41Thr while X gene variants revealed Phe73Val, Ala44Val, Ser146Ala and Ser147Pro. In tumor compartments per se, several mis-sense mutations were detected, notably the classic T1762A/A1764G mutation in the basal core promoter. In addition, a virus surface antigen mis-sense mutation resulting in M125T was detected in all the samples and could account for surface antigen negativity and occult HBV status. It would be interesting to further explore if a temporal accumulation of viral variants within a favored niche, like patients’ lymphocytes, could bestow survival advantage to the virus, and if certain pro-oncogenic HBV variants could drive lymphomagenesis in DLBCL.

Hepatitis B infection in the general population of China: a systematic review and meta-analysis

BACKGROUND

Hepatitis B virus (HBV) infection is a major public health problem in China. Over a decade has passed since the last National Hepatitis Seroepidemiological Survey was conducted in 2006. The lack of updated data on hepatitis B in China makes assessing the current prevalence and burden of the disease inadequate. In response to the above situation, a systematic review and meta-analysis was conducted to provide a better understanding of hepatitis B epidemiology in the general population of China.

METHODS

A systematic search was conducted in international databases (Medline through PubMed, EMBASE, Cochrane, Web of Science) and national databases (CBM, CNKI, WanFang Data) to retrieve primary studies published between January 1, 2013 and December 31, 2017. The pooled prevalence of HBV infection and 95% confidence intervals were calculated. Quality assessment, heterogeneity testing and publication bias assessment were also performed.

RESULTS

Of the 27 studies included in the meta-analysis, the pooled estimated prevalence of HBV infection in the general population of China from 2013 to 2017 was 6.89% (95% CI:5.84-7.95%), which could be extrapolated to an estimated population of 84 million living with HBsAg in 2018. The prevalence of HBV infection in males was higher than that in females (5.88% vs 5.05%), and rural areas had a higher prevalence than urban areas (5.86% vs 3.29%). The highest prevalence of HBV infection was reported in Western provinces (8.92, 95% CI: 7.19-10.64%). In adults older than 20 years, the prevalence of HBV infection was approximately 7%, which was higher than that in children.

CONCLUSION

The prevalence of HBV infection in the general population of China was classified as higher intermediate prevalence (5-7.99%), of which more than 90% of the HBV infection population included adults older than 20 years. The blocking of mother-to-infant hepatitis B transmission and plans involving timely birth dose of hepatitis B vaccine within 24 h should be implemented. Additionally, improving the quality of life and survival rate of the infected population through antiviral therapy and high-risk adult vaccination will be the priority of our future work. Moreover, various control measures should be implemented in different provinces across China.

The efficiency of low-dose hepatitis B immunoglobulin plus nucleos(t)ide analogs in preventing posttransplant hepatitis B virus recurrence

Background/aim

In this study, the efficiency of using low-dose hepatitis B immunoglobulin (HBIG) plus antiviral treatment according to individual needs has been evaluated in posttransplant hepatitis B virus (HBV) patients.

Materials and methods

We retrospectively evaluated 179 patients who were admitted between 2009 and 2014. Five thousand IU intravenous HBIG was given in the anhepatic phase, and 400 IU/day intramuscular (IM) HBIG was given in the posttransplant period. After HBsAg seroconversion, 400 IU IM HBIG was continued as prophylaxis every two weeks.

Results

The average follow-up period was 26 (2–65) months. Seventy patients had hepatocellular carcinoma (HCC). The HBV recurrence was 4.5% in the first year, and 5.8% in the third year. The HBsAg became negative in 11 (2–63) days, and anti-HBs became positive in 9 (1–31) days. HBsAg positivity occurred in 6 patients during the follow-up period. Five of these patients were those who underwent transplantation due to HCC. In 5 of the HCC patients, in whom HBsAg became positive, tumor recurrence was observed after 0.3–9.9 months. HBsAg positivity was more frequently detected in patients with HCC (P = 0.009).

Conclusion

The HBV recurrence should be evaluated as a predictor of the HCC recurrence in patients who were transplanted due to HCC.

Update of the statements on biology and clinical impact of occult hepatitis B virus infection

In October 2018 a large number of international experts with complementary expertise came together in Taormina to participate in a workshop on occult hepatitis B virus infection (OBI). The objectives of the workshop were to review the existing knowledge on OBI, to identify issues that require further investigation, to highlight both existing controversies and newly emerging perspectives, and ultimately to update the statements previously agreed in 2008. This paper represents the output from the workshop.

LncRNA PCNAP1 modulates hepatitis B virus replication and enhances tumor growth of liver cancer

Rationale: Hepatitis B virus (HBV) is a major risk factor for liver cancer, in which HBV covalently closed circular DNA (cccDNA) plays crucial roles. However, the effect of pseudogene-derived long noncoding RNAs (lncRNAs) acting as functional regulators of their ancestral gene expression on HBV replication and hepatocellular carcinoma (HCC) remains unclear. In this study, we speculated that the pseudogene-derived lncRNA PCNAP1 and its ancestor PCNA might modulate HBV replication and promote hepatocarcinogenesis.

Methods: We investigated the roles of lncRNA PCNAP1 in contribution of HBV replication through modulating miR-154/PCNA/HBV cccDNA signaling in hepatocarcinogenesis by using CRISPR/Cas9, Southern blot analysis, confocal assays, et al. in primary human hepatocytes (PHH), HepaRG cells, HepG2-NTCP cells, hepatoma carcinoma cells, human liver-chimeric mice model, transgenetic mice model, in vitro tumorigenicity and clinical patients.

Results: Interestingly, the expression levels of PCNAP1 and PCNA were significantly elevated in the liver of HBV-infectious human liver-chimeric mice. Clinically, the mRNA levels of PCNAP1 and PCNA were increased in the liver of HBV-positive/HBV cccDNA-positive HCC patients. Mechanistically, PCNA interacted with HBV cccDNA in a HBc-dependent manner. PCNAP1 enhanced PCNA through sponging miR-154 targeting PCNA mRNA 3′UTR. Functionally, PCNAP1 or PCNA remarkably enhanced HBV replication and accelerated the growth of HCC in vitro and in vivo.

Conclusion: We conclude that lncRNA PCNAP1 enhances the HBV replication through modulating miR-154/PCNA/HBV cccDNA signaling and the PCNAP1/PCNA signaling drives the hepatocarcinogenesis. Our finding provides new insights into the mechanism by which lncRNA PCNAP1 enhances HBV replication and hepatocarcinogenesis.

Viral integration drives multifocal HCC during the occult HBV infection

BACKGROUND & AIMS

Although the prognosis of patients with occult hepatitis B virus (HBV) infection (OBI) is usually benign, a small portion may undergo cirrhosis and subsequently hepatocellular carcinoma (HCC). We studied the mechanism of life-long Integration of virus DNA into OBI host's genome, of which may induce hepatocyte transformation.

METHODS

We applied HBV capture sequencing on single cells from an OBI patient who, developed multiple HCC tumors and underwent liver resection in May 2013 at Tongji Hospital in China. Despite with the undetectable virus DNA in serum, we determined the pattern of viral integration in tumor cells and adjacent non-tumor cells and obtained the details of the viral arrangement in host genome, and furthermore the HBV integrated region in cancer genome.

RESULTS

HBV captured sequencing of tissues and individual cells revealed that samples from multiple tumors shared two viral integration sites that could affect three host genes, including CSMD2 on chr1 and MED30/EXT1 on chr8. Whole genome sequencing further indicated one hybrid chromosome formed by HBV integrations between chr1 and chr8 that was shared by multiple tumors. Additional 50 poorly differentiated liver tumors and the paired adjacent non-tumors were evaluated and functional studies suggested up-regulated EXT1 expression promoted HCC growth. We further observed that the most somatic mutations within the tumor cell genome were common among the multiple tumors, suggesting that HBV associated, multifocal HCC is monoclonal in origin.

CONCLUSION

Through analyzing the HBV integration sites in multifocal HCC, our data suggested that the tumor cells were monoclonal in origin and formed in the absence of active viral replication, whereas the affected host genes may subsequently contribute to carcinogenesis.

Free episomal and integrated HBV DNA in HBsAg-negative patients with intrahepatic cholangiocarcinoma

There is evidence that chronic hepatitis B virus (HBV) infection is associated with an increased risk of intrahepatic cholangiocarcinoma (ICC) development, and it has been hypothesized an etiological role of HBV in the development of this tumor. Very little is known about occult HBV infection (OBI) in ICC. Aims of the study were to investigate the OBI prevalence and to characterize the HBV molecular status at intrahepatic level in OBI-positive cases with ICC.

Frozen liver tumor specimens from 47 HBV surface-antigen-negative patients with ICC and 41 paired non-tumor liver tissues were tested for OBI by 4 different HBV-specific nested PCR. Covalently closed circular HBV DNA (HBV cccDNA) and viral integrations were investigated in OBI-positive cases.

HBV DNA was detected in tumor and/or non-tumor specimens from 29/47 (61.7%) ICC patients. HBV cccDNA was found in tissues from 5/17 (34.5%) cases examined. HBV integration was detected in 4/10 (40%) tumor tissues tested and involved HBx and HBV-core gene sequences in 3 and 1 cases, respectively. Viral integration occurred: (a) 9,367 nucleotides upstream of the cat-eye-syndrome critical region protein-5-isoform coding sequence; (b) within the cystinosin isoform-1-precursor gene; (c) within the thromboxane-A-synthase-1 gene; (d) within the ATPase phospholipid transporting 9B gene.

Occult HBV infection is highly prevalent in patients with ICC. Both free viral genomes and integrated HBV DNA can be present in these cases. These results suggest an involvement of HBV in the carcinogenic process leading to ICC development even in cases with occult infection.