Higher proportion of viral basal core promoter mutant increases the risk of liver cirrhosis in hepatitis B carriers

Evolution and diversity of the hepatitis B virus genome: Clinical implications

Hepatitis B virus (HBV) infection remains a significant global health burden. The genetic variation of HBV is complex. HBV can be divided into nine genotypes, which show significant differences in geographical distribution, clinical manifestations, transmission routes and treatment response. In recent years, substantial progress has been made through various research methods in understanding the development, pathogenesis, and antiviral treatment response of clinical disease associated with HBV genetic variants. This progress provides important theoretical support for a deeper understanding of the natural history of HBV infection, virus detection, drug treatment, vaccine development, mother-to-child transmission, and surveillance management. This review summarizes the mechanisms of HBV diversity, discusses methods used to detect viral diversity in current studies, and the impact of viral genome variation during infection on the development of clinical disease.

Lower HBV DNA level is associated with more severe liver fibrosis in HBeAg-positive chronic hepatitis B with normal alanine transaminase

BACKGROUND

The association of hepatitis B virus (HBV) DNA levels and liver fibrosis in chronic hepatitis B (CHB) patients with immune-tolerant phase remains unclear. We explored the association between liver fibrosis and HBV DNA levels in HBeAg-positive CHB patients with normal alanine transaminase (ALT) with relatively high HBV DNA.

METHODS

Six hundred and twenty-two HBeAg-positive CHB patients with normal ALT were included. Patients were divided into three categories: low (6 log10 IU/mL ≤ HBV DNA < 7 log10 IU/mL), moderate (7 log10 IU/mL ≤ HBV DNA < 8 log10 IU/mL), and high (HBV DNA ≥ 8 log10 IU/mL). APRI, FIB-4, transient elastography, or liver biopsy were used to assess liver fibrosis.

RESULTS

The median age of patients was 33.0 years and 57.9% patients were male. 18.8%, 52.1%, and 29.1% of patients had low, moderate, and high HBV DNA levels, respectively. The APRI (0.33 vs. 0.26 vs. 0.26, P < 0.001), FIB-4 (1.03 vs. 0.71 vs. 0.68, P < 0.001), and LSM values (7.6 kPa vs. 5.6 kPa vs. 5.5 kPa, P = 0.086) were higher in low HBV DNA group than other two groups. Low HBV DNA group had higher proportions of significant fibrosis (24.8% vs. 9.9% vs. 3.3%, P < 0.001) and cirrhosis (7.7% vs. 2.5% vs. 1.1%, P = 0.004) than moderate and high HBV DNA groups. Moderate (OR 3.095, P = 0.023) and low (OR 4.968, P = 0.003) HBV DNA were independent risk factors of significant fibrosis.

CONCLUSION

Lower HBV DNA level was associated with more severe liver fibrosis in HBeAg-positive CHB patients with ALT.

Occult Hepatitis B Virus Infection and Liver Fibrosis in Chinese Patients

BACKGROUND

The impact of hepatitis B surface antigen (HBsAg)-negative/hepatitis B virus (HBV) DNA-positive occult HBV infection (OBI) on the severity of liver fibrosis remains unclear.

METHODS

A total of 1772 patients negative for HBsAg but positive for antibody to hepatitis B core antigen (HBcAg), stratified by the presence or absence of OBI, were selected for long-term carriage leading to elevation of ≥2 of 4 liver fibrosis indexes-hyaluronic acid (HA), laminin, type III procollagen peptide (PCIII), and type IV collagen (CIV)-at testing in a Chinese hospital. Patients were tested for serum viral load, HBV markers, and histopathological changes in liver biopsy specimens.

RESULTS

OBI was identified in 148 patients with liver fibrosis (8.4%), who had significantly higher levels of HA, laminin, PCIII, and CIV than 1624 fibrotic patients without OBI (P < .05). In 36 patients with OBI who underwent liver biopsy, significant correlations were observed between OBI viral load and serum HA levels (P = .01), PCIII levels (P = .01), and pathological histological activity index (HAI) scores (P < .001), respectively; HAI scores and PCIII levels (P = .04); HBcAg immunohistochemical scores and HA levels (P < .001); and HBcAg immunohistochemical scores and PCIII levels (P = .03). Positive fluorescent in situ hybridization results were significantly more frequent in patients with OBIs (80.6% vs 37.5% in those without OBIs). Among patients with OBIs, HBcAg was detected in the liver tissue in 52.8% and HBsAg in 5.6%.

CONCLUSIONS

OBI status appears to be associated with liver fibrosis severity.

A Narrative Review on the Specific Pattern of HBV Genotype in Bangladesh: Clinical Implications for Management

Background and aims

Bangladesh's unique epidemiological landscape presents an intriguing puzzle. This South Asian nation, with its complex sociodemographic and environmental factors, is home to a diverse array of hepatitis-B virus (HBV) genotypes, identified as Genotype C, with Genotypes D and A also making a significant contribution to the viral landscape. Reviewing such insights is necessary not only to underscore the country's regional diversity in HBV strains but also to bring into focus the clinical implications these genetic variations may have on disease progression and management.

Methods

A thorough database search covered various sources using relevant keywords like "Hepatitis B virus genotypes", "HBV genotypes in Bangladesh", and "HBV clinical implications". The review synthesized findings and analyzed HBV genotype prevalence and clinical implications in Bangladesh.

Results

Genotypes C and D collectively represent 82% of chronic hepatitis-B infection (CHB) cases in Bangladesh, underscoring their regional prevalence. The geographic context is pivotal in understanding HBV infection dynamics and disease progression in this area. Notably, genotype C and the presence of A1762T/G1764A mutations appear to have a distinct impact on disease development, potentially affecting the immune response in CHB patients. This highlights the need for tailored management approaches in this specific region. Further research is vital to confirm and elaborate on these findings, particularly in relation to how these mutations influence the host's immune response.

Conclusion and clinical significance

In summary, studies on HBV genotypes in Bangladesh stress the need for genotype-specific clinical considerations and more research to improve diagnostics and therapies.

How to cite this article

Raihan R, Akbar SMF. A Narrative Review on the Specific Pattern of HBV Genotype in Bangladesh: Clinical Implications for Management. Euroasian J Hepato-Gastroenterol 2023;13(2):152-158.

Low Hepatitis B Core-Related Antigen Levels Correlate Higher Spontaneous Seroclearance of Hepatitis B Surface Antigen in Chronic Hepatitis B Patients With High Hepatitis B Surface Antigen Levels

BACKGROUND & AIMS

Seroclearance of hepatitis B surface antigen (HBsAg) indicates functional cure for hepatitis B virus (HBV) infection. Low HBsAg levels can predict HBsAg seroclearance over time. However, little is known about the association between hepatitis B core-related antigen (HBcrAg) levels and spontaneous seroclearance of HBsAg.

METHODS

We conducted a retrospective cohort study including 2614 treatment-naïve patients with chronic HBV infection who received long-term follow-up at the National Taiwan University Hospital. The primary end point was spontaneous HBsAg seroclearance. We aimed to explore whether HBcrAg levels could predict HBsAg seroclearance, especially for patients with HBsAg levels >1000 IU/mL.

RESULTS

There were 465 patients who cleared HBsAg with 32,414.72 person-years of follow-up, with a mean clearance rate of 1.43% per year. We found that lower HBcrAg levels at baseline were associated with an increased likelihood of HBsAg seroclearance (log rank P < .001). When restricting the study population to 1539 patients with HBsAg levels >1000 IU/mL, only HBcrAg <10,000 U/mL (vs ≥100,000 U/mL) served as an independent viral predictor for HBsAg seroclearance, with adjusted hazard ratio of 1.95 (95% CI, 1.16-3.27). In contrast to the late decline of HBsAg levels (5-9 years before HBsAg seroclearance), HBcrAg levels became undetectable 10-14 years before HBsAg seroclearance. This finding was confirmed by the different annual HBsAg seroclearance rates in the first and second decades of follow-up (0.97% vs 3.75%; P < .001) in patients achieving undetectable HBcrAg levels.

CONCLUSIONS

Lower serum HBcrAg levels were associated with increased probability of HBsAg seroclearance over time. In patients with HBsAg levels >1000 IU/mL, clearing HBcrAg may serve as an early biomarker for HBsAg seroclearance.

High-risk population of progressive hepatic fibrosis in chronic hepatitis B patients on antiviral therapy

BACKGROUND

Progressive hepatic fibrosis leads to hepatocellular carcinoma (HCC) and decompensated cirrhosis. The aim of this study was to identify the high-risk population for progressive hepatic fibrosis and the incidence of HCC and decompensated cirrhosis in chronic hepatitis B (CHB) patients with antiviral therapy.

METHODS

The data came from a multicenter, center-randomized, double-blind clinical trial that analyzed only patients in the ETV-treated arm. There was 156 hepatitis B e antigen (HBeAg)-positive and 135 HBeAg-negative patients in 14 institutions. The primary endpoint was fibrosis reversal on 72-week Entecavir (ETV) treatment. The 7-year cumulative incidence of HCC and decompensated cirrhosis were analyzed. Multivariate logistic and LASSO regression analyses were used to screen variables associated with fibrosis reversal.

RESULTS

86/156 (55%) HBeAg-positive and 58/135 (43%) HBeAg-negative patients achieved fibrosis reversal on 72-week ETV treatment. Average age was 43 years, 203 (69.8%) was male, and 144 (49.5%) patients had cirrhosis. Age ≥ 40 years (OR: 0.46, 95% CI 0.23-0.93) and HBcrAg ≥ 8.23 log U/ml (OR: 2.72, 95% CI 1.33-5.54) in HBeAg-positive patients and HBV genotype C (OR: 0.44, 95% CI 0.21-0.97) in HBeAg-negative patients were independent factors of fibrosis reversal. It was confirmed in patients with cirrhosis. After 7-year ETV treatment, seven (4.5%) HBeAg-positive patients occurred HCC or decompensated cirrhosis, including four patients with age ≥ 40 years and six with HBcrAg 8.23log U/ml, while twelve (8.9%) HBeAg-negative patients occurred, including eleven with HBV genotype C.

CONCLUSIONS

HBeAg-positive patients with a low HBcrAg level or old age, and HBeAg-negative patients with HBV genotype C tended to develop progressive hepatic fibrosis and had a high incidence of HCC and decompensated cirrhosis, even on ETV treatment.

Hepatitis Virus and Hepatocellular Carcinoma: Recent Advances

Hepatocellular carcinoma (HCC) remains a global health challenge, causing 600,000 deaths each year. Infectious factors, including hepatitis B virus (HBV), hepatitis C virus (HCV) and hepatitis D virus (HDV), have long been considered the major risk factors for the development and progression of HCC. These pathogens induce hepatocyte transformation through a variety of mechanisms, including insertional mutations caused by viral gene integration, epigenetic changes, and the induction of long-term immune dysfunction. The discovery of these mechanisms, while advancing our understanding of the disease, also provides targets for new diagnostic and therapeutic approaches. In addition, the discovery and research of chronic HEV infection over the past decade indicate that this common hepatitis virus also seems to have the potential to induce HCC. In this review, we provide an overview of recent studies on the link between hepatitis virus and HCC, as well as new diagnostic and therapeutic approaches to HCC based on these findings. Finally, we also discuss the potential relationship between HEV and HCC. In conclusion, these associations will further optimize the diagnosis and treatment of infection-associated HCC and call for better management policies.

Hepatitis B Core-Related Antigen Stratifies the Risk of Liver Cancer in HBeAg-Negative Patients With Indeterminate Phase

INTRODUCTION

Many patients with chronic hepatitis B (CHB) are classified as indeterminate patients because they fall outside the defined CHB phases. We aimed to explore hepatocellular carcinoma (HCC) risk in hepatitis B e antigen (HBeAg)-negative patients with indeterminate phase and investigated whether the risk could be stratified by serum levels of hepatitis B core-related antigen (HBcrAg).

METHODS

Two retrospective cohorts enrolling HBeAg-negative, treatment-naïve CHB patients without cirrhosis were constructed (N = 2,150 in Taiwanese discovery cohort and N = 1,312 in Japanese validation cohort with a mean follow-up period of 15.88 and 12.07 years, respectively). The primary end point was HCC development.

RESULTS

According to the American Association for the Study of Liver Disease guidelines, 990 (46%) HBeAg-negative patients had indeterminate CHB phase at baseline in the Taiwanese cohort. Compared with the patients with inactive CHB and those with immune-active CHB, the indeterminate patients exhibited intermediate but diverse risk of HCC. When HCC risk was stratified by a HBcrAg level of 10,000 U/mL, 10-year HCC cumulative incidence was 0.51% and 5.33% for low HBcrAg and high HBcrAg groups, respectively, with a hazard ratio of 4.47 (95% confidence interval: 2.62-7.63). This cutoff was validated to stratify HCC risk not only in different subgroup analyses but also in an independent Japanese cohort. Finally, the overall HBeAg-negative CHB patients could be simply reclassified into high-risk and low-risk groups by combining ALT, hepatitis B virus DNA, and HBcrAg levels in both cohorts.

DISCUSSION

Serum HBcrAg level of 10,000 U/mL stratifies HCC risk in HBeAg-negative patients with indeterminate phase, which is useful for optimizing their clinical management.

Review on hepatitis B virus precore/core promoter mutations and their correlation with genotypes and liver disease severity

Of 350 million people worldwide are chronically infected with hepatitis B virus (HBV) and are at risk of developing cirrhosis and hepatocellular carcinoma (HCC) later in life. HBV is the most diverse DNA virus, and its genome is composed of four open reading frames: Presurface antigen/surface antigen gene (preS/S), precore/core gene (preC/C), polymerase gene (P), and the X gene (X). HBV produces quasispecies naturally or in response to antiviral agents because of the absence of proofreading activity amid reverse transcription and a high replication rate. The virus has 10 genotypes (A to J) with different geographical distributions. There are various HBV mutations in the HBV genome, including preC/C mutations, preS/S mutations, P gene mutations, and X gene mutations. The core promoter region plays a vital part in the replication, morphogenesis and pathogenesis of the virus. The precore region also plays a crucial role in viral replication. Both core promoter and precore mutations rescue the virus from host immune surveillance and result in the formation of mutated strains that may have altered pathogenicity. preC/C mutations are associated with liver disease progression. Precore mutations stop hepatitis B e antigen (HBeAg) production and basal core promoter mutations downregulate HBeAg production. Mutations in the basal core promoter are also associated with increased HBV replication and an increased incidence of advanced liver diseases such as cirrhosis and HCC. The emergence of antiviral-resistant mutations is the main reason for treatment failure. This review focuses mainly on preC/C promoter mutations and their correlation with genotypes and liver disease severity. Thorough perception and knowledge of HBV genetic variety and mutants could be vital to discover techniques for the prognosis and control of HBV infection.

Novel X gene point mutations in chronic hepatitis B and HBV related cirrhotic patients

INTRODUCTION

HBx is a multifunctional modulator viral protein with key roles in various biological processes such as signal transduction, transcription, proliferation, and cell apoptosis. Also, HBx has an important role in the progression of cirrhosis and hepatocellular carcinoma (HCC). This study aimed to determine mutations in X gene, enhancer II (EnhII), and basal core promoter (BCP) of genotype D of Hepatitis B Virus (HBV) in cirrhotic and chronic HBV patients.

MATERIAL AND METHODS

This cross-sectional study was performed on 68 cases with chronic HBV (cHBV) and 50 cases with HBV related cirrhosis. Serum samples were obtained for genomic DNA extraction. Semi-nested PCR was used to amplify the HBx region. Point mutations in the HBx region were detected by sequencing.

RESULT

Novel mutations were detected, including C1491G, C1500T, G1613T, and G1658T in the N-terminal of the X gene. The frequency of C1481T/G1479A, T1498C, C1500T, G1512A, A1635T, C1678T, A1727T, and A1762T/ G1764A/ C1773T was significantly higher in cirrhotic patients compared to chronically HBV infected ones. A higher rate of A1635T, C1678T, A1727T, A1762T, G1764A, and C1773T was observed in cirrhotic patients.

CONCLUSION

Our findings showed that the frequency of mutations in the basal-core promoter, enhancer II, and regulatory region of the HBx gene was more seen in cirrhotic patients than in chronic HBV cases. Novel mutations were detected in the HBx gene, causing amino acid substitutions; however, the clinical impact of these novel mutations is yet to be cleared.

Interpretation of HBV Serologies

Hepatitis B was discovered by researchers who were investigating jaundice associated with blood transfusions as well as parenterally administered medications. Through trial and error, the HBV was identified. There are specific tests that detect HBV infection, whether it is a previous exposure or active infection. The various HBV serologies are reviewed in this work as well. Hepatitis B surface antigen has emerged as a tool in defining treatment endpoint and its significance is reviewed. HBV genotypes are distributed uniquely throughout the world, in particular, genotype C is associated with higher rates of hepatocellular carcinoma. Various HBV genotypes and their impact on the clinical course are discussed. The relationship of HBV serologies and HBV DNA to disease progression is outlined. There are specific recommendations on monitoring those infected with HBV and this is reviewed here. HBV mutations have an impact on the disease course and those of significance are also discussed.

Immunogenicity and Antiviral Response of Therapeutic Hepatitis B Vaccination in a Mouse Model of HBeAg-Negative, Persistent HBV Infection

During the natural course of chronic hepatitis B virus (HBV) infection, the hepatitis B e antigen (HBeAg) is typically lost, while the direct transmission of HBeAg-negative HBV may result in fulminant hepatitis B. While the induction of HBV-specific immune responses by therapeutic vaccination is a promising, novel treatment option for chronic hepatitis B, it remains unclear whether a loss of HBeAg may influence its efficacy or tolerability. We therefore generated an adeno-associated virus (AAV)-vector that carries a 1.3-fold overlength HBV genome with a typical stop-codon mutation in the pre-core region and initiates the replication of HBeAg(-) HBV in mouse livers. Infection of C57BL/6 mice established persistent HBeAg(-) HBV-replication without any detectable anti-HBV immunity or liver damage. HBV-carrier mice were immunized with TherVacB, a therapeutic hepatitis B vaccine that uses a particulate HBV S and a core protein for prime vaccination, and a modified vaccinia Ankara (MVA) for boost vaccination. The TherVacB immunization of HBeAg(+) and HBeAg(-) HBV carrier mice resulted in the effective induction of HBV-specific antibodies and the loss of HBsAg but only mild liver damage. Intrahepatic, HBV-specific CD8 T cells induced in HBeAg(-) mice expressed more IFNγ but showed similar cytolytic activity. This indicates that the loss of HBeAg improves the performance of therapeutic vaccination by enhancing non-cytolytic effector functions.

Increased hepatitis B virus quasispecies diversity is correlated with liver fibrosis progression

Host immune response and viral factors are involved in disease progression in patients with chronic hepatitis B virus (HBV) infection. However, the relationship between HBV quasispecies and liver fibrosis progression remains unclear. In this study, 447 patients with chronic HBV infection, including 239 with chronic hepatitis B (CHB), 104 with liver cirrhosis (LC) and 104 with hepatocellular carcinoma (HCC) were enrolled. The 239 CHB patients were divided into groups F1, F2, and F3 according to liver fibrosis score. Four fragments of the HBV genome were determined and analyzed using next-generation sequencing. Specific mutations, such as A1762T, G1764A and G1896A, in the BCP/PC region were more common in patients with advanced liver disease and formed the majority of the viral quasispecies pool in patients with LC and HCC. The viral complexity and diversity increased as the fibrosis progressed, especially in patients with CHB who were comparable in age but at different stages of fibrosis. Patients with early-stage fibrosis experienced higher purifying selection pressure in the four sequenced regions, whereas different protein-coding region experienced different negative selection with disease progression. HBV quasispecies diversity may increase fibrosis progression in CHB patients with aging under immune selection.

Viral quasispecies quantitative analysis: a novel approach for appraising the immune tolerant phase of chronic hepatitis B virus infection

Few non-invasive models were established for precisely identifying the immune tolerant (IT) phase from chronic hepatitis B (CHB). This study aimed to develop a novel approach that combined next-generation sequencing (NGS) and machine learning algorithms using our recently published viral quasispecies (QS) analysis package. 290 HBeAg positive patients from whom liver biopsies were taken were enrolled and divided into a training group (n = 148) and a validation group (n = 142). HBV DNA was extracted and QS sequences were obtained by NGS. Hierarchical clustering analysis (HCA) and principal component analysis (PCA) based on viral operational taxonomic units (OTUs) were performed to explore the correlations among QS and clinical phenotypes. Three machine learning algorithms, including K-nearest neighbour, support vector machine, and random forest algorithm, were used to construct diagnostic models for IT phase classification. Based on histopathology, 90 IT patients and 200 CHB patients were diagnosed. HBsAg titres for IT patients were higher than those of CHB patients (p < 0.001). HCA and PCA analysis grouped IT and CHB patients into two distinct clusters. The relative abundance of viral OTUs differed mainly within the BCP/precore/core region and was significantly correlated with liver inflammation and fibrosis. For the IT phase classification, all machine-learning models showed higher AUC values compared to models based on HBsAg, APRI, and FIB-4. The relative abundance of viral OTUs reflects the severity of liver inflammation and fibrosis. The novel QS quantitative analysis approach could be used to diagnose IT patients more precisely and reduce the need for liver biopsy.

Chronic hepatitis B: the demise of the 'inactive carrier' phase

Chronic hepatitis B (CHB) remains a global healthcare burden. Although the recent developments in the field have led to a reduction in incidence, the morbidity and mortality including liver cirrhosis and hepatocellular carcinoma (HCC) remain a formidable challenge. Advances in understanding the immunopathogenesis of CHB have led to a recent change in clinical categorization. EASL introduced the term hepatitis B 'e' antigen (HBeAg)-negative chronic infection, to replace the historical term 'inactive carrier' disease phase, the commonest CHB phase. Although this disease phase is associated with a favorable prognosis, it is not a truly 'inactive' disease phase with no ostensible liver disease, as inferred by the previous anachronistic terminology, and the risk of spontaneous reactivation and the potential risk of disease progression and HCC development are not negligible. Likewise, the APASL also uses the term "Incidentally Detected Asymptomatic Hepatitis B surface antigen (HBsAg)-positive Subject (IDAHS)", comprising all HBsAg-positive subjects who are incidentally detected during routine tests, without any previous or present symptoms of liver disease. This entity includes HBV infection with varied stages of liver disease. Antiviral treatment is generally reserved for patients with active inflammation and/or at risk of disease progression and HCC development. HBsAg loss is considered an optimal treatment endpoint, and may also be achievable in HBeAg-negative chronic infection and IDAHS. In light of this, and the emerging novel HBV therapies, lowering the treatment threshold and a 'Treat All' approach should now be considered. In this review, we summarize the literature and guidance on HBeAg-negative chronic infection, and we make a concerted effort to present the reasons why the one-dimensional term 'inactive carrier' should be abandoned.

One-year Fibrosis-4 index helps identify minimal HCC risk in non-cirrhotic chronic hepatitis B patients with antiviral treatment

BACKGROUND AND AIMS

Fibrosis-4 (FIB-4) index is a HCC predictor in chronic hepatitis B (CHB) patients. However, little is known about whether FIB-4 helps identify non-cirrhotic CHB patients with minimal HCC risk after prolonged nucleos(t)ide analogue (NA) therapy.

METHODS

A total of 1936 ethnically diverse, non-cirrhotic CHB patients were enrolled in this retrospective multi-national study. All patients received prolonged NA treatment, including entecavir and tenofovir disoproxil fumarate. We explored whether FIB-4 cutoff of 1.30, a marker indicative of mild fibrosis severity, could stratify HCC risks in these patients.

RESULTS

A total of 48 patients developed HCC after a mean follow-up of 6.98 years. FIB-4 level at 1 year after treatment (1-year FIB-4) was shown to be associated with HCC development and was superior to pre-treatment FIB-4 value. When patients were stratified by 1-year FIB-4 of 1.30, the high FIB-4 group was at an increased HCC risk compared to the low FIB-4 group, with a hazard ratio of 4.87 (95% confidence interval: 2.48-9.55). Multivariable analysis showed that sex and 1-year FIB-4 were independent predictors, with none of the 314 female patients with low 1-year FIB-4 developing HCC. Finally, 1-year FIB-4 of 1.30 consistently stratified HCC risks in patients with low PAGE-B score, a score composed of baseline age, sex and platelet count, and the annual incidence rate of HCC was 0.11% in those with PAGE-B < 10 + 1-year FIB-4 < 1.30.

CONCLUSIONS

In non-cirrhotic CHB patients receiving prolonged NA therapy, 1-year FIB-4 < 1.30 is useful for identifying those with minimal HCC risk by combining with female sex or low PAGE-B score.

Comprehensive Analysis of Clinically Significant Hepatitis B Virus Mutations in Relation to Genotype, Subgenotype and Geographic Region

Hepatitis B virus (HBV) is a highly variable DNA virus due to its unique life cycle, which involves an error-prone reverse transcriptase. The high substitution rate drives the evolution of HBV by generating genetic variants upon which selection operates. HBV mutants with clinical implications have been documented worldwide, indicating the potential for spreading and developing their own epidemiology. However, the prevalence of such mutants among the different HBV genotypes and subgenotypes has not been systematically analyzed. In the current study, we performed large-scale analysis of 6,479 full-length HBV genome sequences from genotypes A-H, with the aim of gaining comprehensive insights into the relationships of relevant mutations associated with immune escape, antiviral resistance and hepatocellular carcinoma (HCC) development with HBV (sub)genotypes and geographic regions. Immune escape mutations were detected in 10.7% of the sequences, the most common being I/T126S (1.8%), G145R (1.2%), M133T (1.2%), and Q129R (1.0%). HBV genotype B showed the highest rate of escape mutations (14.7%) while genotype H had no mutations (P < 0.001). HCC-associated mutations were detected in 33.7% of the sequences, with significantly higher frequency of C1653T, T1753V and A1762T/G1764A in genotype G than C (P < 0.001). The overall frequencies of lamivudine-, telbivudine-, adefovir-, and entecavir-resistant mutants were 7.3, 7.2, 0.5, and 0.2%, respectively, while only 0.05% showed reduced susceptibility to tenofovir. In particular, the highest frequency of lamivudine-resistant mutations was observed in genotype G and the lowest frequency in genotype E (32.5 and 0.3%; P < 0.001). The prevalence of HBV mutants was also biased by geographic location, with North America identified as one of the regions with the highest rates of immune escape, antiviral resistance, and HCC-associated mutants. The collective findings were discussed in light of natural selection and the known characteristics of HBV (sub)genotypes. Our data provide relevant information on the prevalence of clinically relevant HBV mutations, which may contribute to further improvement of diagnostic procedures, immunization programs, therapeutic protocols, and disease prognosis.

Precise analysis of the effect of basal core promoter/precore mutations on the main phenotype of chronic hepatitis B in mouse models

High replication and mutation rates of hepatitis B virus (HBV) often lead to reduced or suppressed hepatitis B e antigen expression. The most common mutations are genomic variations in the basal core promoter (BCP) and pre-core (PC) regions. However, the effect of BCP/PC mutations on HBV phenotype in vivo remains unclear. We compared and analyzed BCP/PC mutations and BCP/PC reverse mutations in mouse models. In addition to terminating the expression of HBeAg, BCP/PC mutations also resulted in a significant decrease in HBsAg, HBV DNA, and cccDNA in the early stage, and an obvious increase in serum alanine aminotransferase throughout the transfection period. In both groups, serum HBV DNA was positively correlated with intracellular HBV DNA and cccDNA. Further, we found that interleukin-4 (IL-4) and L-10 levels were significantly lower in the BCP/PC(M) group than in the BCP/PC(R) group at 4 weeks post-injection. However, IL-1β was significantly lower in the BCP/PC(M) group than in the BCP/PC(R) group at 26 weeks post-injection. In summary, we precisely analyzed the effect of BCP/PC mutations on the phenotype in vivo, which is important to evaluating disease progression and treatment responses of variable chronic hepatitis B patients.

Quadruple mutation GCAC1809-1812TTCT acts as a biomarker in healthy European HBV carriers

Many mutation analyses of the HBV genome have been performed in the search for new prognostic markers. However, the Kozak sequence preceding precore was covered only infrequently in these analyses. In this study, the HBV core promoter/precore region was sequenced in serum samples from European inactive HBV carriers. Quadruple mutation GCAC1809-1812TTCT was found with a high prevalence of 42% in the Kozak sequence preceding precore among all HBV genotypes. GCAC1809-1812TTCT was strongly associated with coexistence of basal core promoter (BCP) double mutation A1762T/G1764A and lower HBV DNA levels. In vitro GCAC1809-1812TTCT lead to drastically diminished synthesis of pregenomic RNA (pgRNA), precore mRNA, core, HBsAg, and HBeAg. Calculation of the pgRNA secondary structure suggests a destabilization of the pgRNA structure by A1762T/G1764A that was compensated by GCAC1809-1812TTCT. In 125 patients with HBV-related cirrhosis, GCAC1809-1812TTCT was not detected. While a strong association of GCAC1809-1812TTCT with inactive carrier status was observed, BCP double mutation was strongly correlated with cirrhosis, but this was only observed in absence of GCAC1809-1812TTCT. In conclusion, our data reveal that GCAC1809-1812TTCT is highly prevalent in inactive carriers and acts as a compensatory mutation for BCP double mutation. GCAC1809-1812TTCT seems to be a biomarker of good prognosis in HBV infection.

HBV core promoter/precore region was sequenced in serum samples of European inactive HBV carriers, revealing that GCAC1809-1812TTCT mutation is highly prevalent in inactive carriers.

HBV variants are common in the 'immune-tolerant' phase of chronic hepatitis B

Nucleos(t)ide analogues (NUC) treatment prevents progression of liver fibrosis in subjects with chronic hepatitis B (CHB). However, risk of hepatocellular carcinoma (HCC) persists despite viral suppression. Specific HBV variants have been associated with adverse outcomes, including HCC; however, the frequency of these variants during the seemingly benign immunotolerant (IT) phase is unknown. Next-generation sequencing and detailed virological characterization on a cohort of treatment-naïve IT subjects were performed to determine the frequency of clinically relevant viral variants. Samples from 97 subjects (genotype B/C 55%/45%, median HBV-DNA 8.5 log₁₀ IU/mL, median HBsAg 4.8 log₁₀  IU/mL, median HBeAg 3.6 log₁₀  PEIU/mL) were analysed. Despite subjects being in the IT phase, clinically relevant HBV variants were common at baseline, particularly in the basal core promoter (BCP, overlaps the hepatitis B X (HBx) gene), precore and PreS regions. BCP/HBx variants were independently associated with lower baseline HBeAg, HBsAg and HBV-DNA titres. Precore variants were independently associated with higher baseline ALT. Increased viral diversity was associated with increased age and lower HBV-DNA, HBsAg and HBeAg levels. Low-level (<5%) drug resistance-associated amino acid substitutions in the HBV reverse transcriptase were detected in 9 (9%) subjects at pre-treatment but were not associated with reduced antiviral activity. Future studies should evaluate whether the detection of HBV variant during IT CHB is predictive of progression to immune clearance and poor prognosis, and whether early initiation of antiviral therapy during IT CHB to prevent the selection of HBV variants is clinically beneficial.

HBeAg Negativity Is Associated With More Advanced Liver Fibrosis in Patients With Chronic Hepatitis B: A Propensity Score-Matching Analysis

BACKGROUND

Serum hepatitis B e antigen (HBeAg) status is associated with the progression of chronic hepatitis B (CHB). The authors aimed to investigate the relationship between HBeAg status and liver pathology in CHB patients.

METHODS

A total of 683 treatment-naive CHB patients who had undergone liver biopsy were retrospectively enrolled from 2 medical centers. Propensity score-matching (PSM) method was performed to adjust the imbalance of baseline confounders between HBeAg-positive and HBeAg-negative CHB patients.

RESULTS

HBeAg-negative CHB patients (n=338) exhibited more advanced liver fibrosis than HBeAg-positive CHB patients (n=345) before PSM (P<0.001). However, there were no significant differences in the distribution of inflammation grades between HBeAg-positive and HBeAg-negative CHB patients (P=0.051). Of these 683 CHB patients, 123 patients were included in each group after PSM. HBeAg-negative CHB patients still showed significantly advanced liver fibrosis as compared with HBeAg-positive CHB patients (P=0.03) after PSM. Furthermore, the distribution of liver inflammation grades in the HBeAg-negative CHB patients was also more severe than patients with HBeAg-positive (P=0.037). HBeAg-negative status was identified as an independent risk factor of significant liver fibrosis (P=0.011) by multivariate analysis.

CONCLUSIONS

HBeAg negativity is associated with more advanced liver fibrosis in CHB patients.

Impacts of the Percentage of Basal Core Promoter Mutation on the Progression of Liver Fibrosis After Hepatitis B e Antigen Seroconversion

BACKGROUND

We investigated the relationships among the percentage of hepatitis B virus (HBV) mutations and liver fibrosis after hepatitis B e antigen (HBeAg) seroconversion.

METHODS

We quantified the percentage of HBV mutants by pyrosequencing using serum samples obtained at inflammatory phase and after HBeAg seroconversion in 160 initially HBeAg-positive chronic HBV-infected patients. The relationships between antiviral agents, percentages of HBV mutations, and liver stiffness measurements (LSMs) were analyzed.

RESULTS

We demonstrated that the percentages of A1762T/G1764A mutation are significantly higher in subjects with an LSM >7 kPa than in those with an LSM ≤7 kPa after HBeAg seroconversion. Hepatitis B e antigen seroconversion age is positively correlated with the percentages of A1762T/G1764A mutation at inflammatory phase before HBeAg seroconversion. Subjects who underwent interferon, entecavir, or tenofovir disoproxil fumarate therapy before HBeAg seroconversion possessed a lower percentage of A1762T/G1764A mutation after HBeAg seroconversion. The percentage of A1762T/G1764A ≥20% after HBeAg seroconversion was predictive of an LSM >7 kPa (hazard ratio = 6.37, P = .001). The presence of A1762T/G1764A led to downregulated messenger ribonucleic acid and protein levels of programmed-death ligand-1 (PD-L1) in hepatocytes.

CONCLUSIONS

The percentage of A1762T/G1764A mutations after HBeAg seroconversion was associated with liver fibrosis. The A1762T/G1764A mutation may evoke hepatic inflammation by suppressing PD-L1 in hepatocytes.

HEV superinfection accelerates disease progression in patients with chronic HBV infection and increases mortality in those with cirrhosis

BACKGROUND & AIMS

Acute HEV infection causes varying degrees of liver damage. Although liver-related death due to HEV infection alone is rare in healthy individuals, it is unclear whether HEV superinfection is associated with worse outcomes in patients with chronic HBV infection. Thus, we explored whether HEV superinfection was associated with increased incidence of liver-related death, cirrhosis, and hepatocellular carcinoma (HCC).

METHODS

Serum and data were collected from 2 independent retrospective cohorts of patients with chronic HBV infection, comprising 2,123 patients without cirrhosis and 414 with cirrhosis at baseline, respectively. All the patients were negative for HEV-IgG at enrolment and HEV superinfection was defined by the presence of HEV-IgG seroconversion.

RESULTS

In the non-cirrhotic cohort, 46 of 2,123 patients developed HEV superinfection. Though HEV superinfection was only associated with increased incidence of liver-related death in the overall cohort, it was a risk factor for all 3 endpoints (liver-related death, cirrhosis, and HCC) in a subgroup of 723 HBeAg-negative patients with chronic HBV infection. In addition, the 1-year mortality rate after HEV superinfection was higher in 4 patients who developed cirrhosis during the follow-up than in those who did not (50% vs. 2.4%, p = 0.001). To elucidate the perceived relationship between HEV superinfection and risk of mortality, an independent cohort of cirrhotic patients (n = 414) was further analyzed to control for the inherent increase in mortality risk due to cirrhosis. The 10 cirrhotic patients with HEV superinfection had a higher 1-year mortality rate than those without (30% vs. 0%, p <0.001).

CONCLUSIONS

In both cohorts of patients with chronic HBV infection, acute HEV superinfection increases the risk of liver-related death, especially in those with cirrhosis.

LAY SUMMARY

The mortality caused by acute hepatitis E virus infection is usually low in the healthy population, but it is unclear how it affects patients with chronic hepatitis B virus infection, as they already have compromised liver function. Our data show that the 1-year mortality rate is 35.7% in patients with hepatitis B-related cirrhosis who contract hepatitis E virus. Hepatitis E may accelerate disease progression in patients with chronic hepatitis B.

[Long Term Efficacy of Antiviral Therapy: Mortality and Incidence of Hepatocellular Carcinoma]

Multiple studies have shown that oral antiviral therapies reduced the incidence of hepatocellular carcinoma (HCC) and improved the survival of patients with chronic hepatitis B when compared with that of untreated patients. In particular, entecavir and tenofovir share the qualities of high efficacy in reducing the HBV DNA levels, and they have excellent tolerability and safety. These drugs modified the natural history of liver fibrosis, improve liver function, decrease the incidence of HCC, decrease the need for liver transplantation, and improve survival. Many studies have suggested that long-term antiviral therapy reduces the risk of HCC and liver cirrhosis in patients with chronic hepatitis. The mechanism of these drugs in reducing the risk of HCC is not clear. This article reviews the mechanisms of carcinogenic HBV by conducting a review of the literature on the efficacy of therapy for reducing the risk of HCC. A few recent articles have suggested that tenofovir offers advantages over entecavir in terms of HCC prevention, but these articles have the inherent limitations of observational data. No other head-to-head randomized trials exist. Further randomized studies would help provide stronger evidence of the association between the type of antiviral agent and the HCC outcomes. Only achieving complete viral eradication from the liver will truly decrease the mortality and incidence of HCC.

Baseline Mac-2 Binding Protein Glycosylation Isomer Level Stratifies Risks of Hepatocellular Carcinoma in Chronic Hepatitis B Patients with Oral Antiviral Therapy

BACKGROUND AND AIMS

Mac-2 binding protein glycosylation isomer (M2BPGi) is a novel biomarker correlating with liver fibrosis stages. However, little is known about how it predicts risks of hepatocellular carcinoma (HCC) in chronic hepatitis B (CHB) patients receiving long-term antiviral treatment.

MATERIALS AND METHODS

The study contained 2 parts. The first part was to explore whether M2BPGi could be an HCC predictor in 899 CHB patients receiving long-term entecavir therapy. The second part was to validate the findings in an independent cohort of 384 on-treatment CHB patients with more severe liver disease.

RESULTS

In the discovery cohort, there were 64 patients developing HCC within an average follow-up of 7.01 years. Our data showed that M2BPGi level was positively associated with HCC development. When stratifying the patients by an M2BPGi level of 1.73 (the third quartile), the high M2BPGi group was shown to have an increased HCC risk compared to the low M2BPGi group with hazard ratio of 5.80 (95% CI 3.50-9.60). Furthermore, we found that the M2BPGi level complements PAGE-B score, a well-validated HCC prediction model, to predict HCC development. Lastly, the cutoff was validated in the independent cohort, especially those with an intermediate PAGE-B score.

CONCLUSIONS

In CHB patients receiving long-term antiviral treatment, serum M2BPGi level not only serves as an independent HCC predictor but also complements PAGE-B in stratifying HCC risks.

Approach to the patient with chronic hepatitis B and decompensated cirrhosis

Patients with chronic hepatitis B virus (HBV) can develop progressive fibrosis, cirrhosis and hepatocellular carcinoma. Patients with chronic HBV and cirrhosis are at risk of developing hepatic decompensation and have high mortality without antiviral therapy and/or liver transplantation. Treatment of chronic HBV with antiviral therapy is indicated in all patients with cirrhosis whatever the HBe-antigen status and serum alanine aminotransferase (ALT), so that hepatic decompensation can be prevented. Initiating antiviral therapy in patients with decompensated cirrhosis can improve liver function, Child-Turcotte-Pugh (CTP) and model for end-stage liver disease (MELD) scores, as well as the need for liver transplantation and mortality. Patients with chronic HBV and cirrhosis who do not respond to antiviral therapy with normalization of ALT may have a co-existent liver disorder. One of the most common co-existent liver disorders present in patients with chronic HBV is non-alcoholic fatty liver disease (NAFLD). Patients with chronic HBV, NAFLD and cirrhosis may be at risk of developing decompensated cirrhosis and require a liver transplant. If patients with chronic HBV require liver transplantation, infection of the liver graft with HBV can be prevented with antiviral therapy.

High Level of Hepatitis B Core-Related Antigen Associated With Increased Risk of Hepatocellular Carcinoma in Patients With Chronic HBV Infection of Intermediate Viral Load

BACKGROUND & AIMS

Chronic hepatitis B virus (HBV) infection is a risk factor for hepatocellular carcinoma (HCC). Serum levels of HB core-related antigen (HBcrAg) have been associated with active replication of HBV. We investigated whether HBcrAg levels are associated with development of HCC, especially in patients who do not require antiviral treatment.

METHODS

We collected data from 2666 adults positive for hepatitis B surface antigen (HBsAg), infected with HBV genotypes B or C, and without liver cirrhosis, who had long-term follow-up at the National Taiwan University Hospital from 1985 through 2000. None of the patients received antiviral treatment during the follow-up. Baseline levels of HBV DNA, HBsAg, and HBcrAg were determined retrospectively and participants were followed for a mean of 15.95 years. The primary end point was an association between serum level of HBcrAg and HCC development.

RESULTS

HCC developed in 209 patients in the cohort (incidence rate, 4.91 cases/1000 person-years). We found a positive association between baseline level of HBcrAg and HCC development; HBcrAg level was an independent risk factor in multivariable analysis. In the subgroup of hepatitis B e antigen-negative patients with HBV DNA levels from 2000 to 19,999 IU/mL (intermediate viral load [IVL]) and normal levels of alanine aminotransferase, HBcrAg levels of 10 KU/mL or more identified patients at increased risk of HCC (hazard ratio, 6.29; confidence interval, 2.27-17.48). Patients with an IVL and a high level of HBcrAg had a risk for HCC that did not differ significantly from that of patients with a high viral load (≥20,000 IU/mL). Patients with an IVL but a low level of HBcrAg had a low risk of HCC, with an annual incidence rate of 0.10% (95% confidence interval, 0.04%-0.24%).

CONCLUSIONS

In a long-term follow-up study of 2666 patients with chronic HBV infection (genotypes B or C), level of HBcrAg is an independent risk factor of HCC. Moreover, HBcrAg level of 10 KU/mL identifies patients with an IVL who are at high risk for HCC.

On-treatment monitoring of liver fibrosis with serum hepatitis B core-related antigen in chronic hepatitis B

BACKGROUND

Non-invasive evaluation for liver fibrosis is clinically important, especially in patients with undetectable hepatitis B virus (HBV) DNA treated with nucleoside analogs.

AIM

To clarify the monitoring power of hepatitis B core-related antigen (HBcrAg) for hepatic histologic changes in patients with chronic hepatitis B (CHB) treated with entecavir.

METHODS

This prospective multicenter study used multiple ordinal and multivariate logistics regression analysis to assess variables associated with Ishak fibrosis score and regression for fibrosis regression, respectively, in 403 CHB patients, including 374 with entecavir for 72 weeks (291 underwent paired liver biopsy) and 29 as controls.

RESULTS

Level of HBcrAg correlated negatively with liver fibrosis staging (γ = -0.357, P < 0.001) in hepatitis B e antigen (HBeAg)-positive patients, and positively with liver fibrosis staging in HBeAg-negative patients. Higher HBcrAg concentration was associated with younger age, HBeAg positive status, high HBV DNA loads, high level of hepatitis B surface antigen (HBsAg) and higher necroinflammation, but not with HBV genotype. Serum concentration of HBcrAg, basal core promoter/precore (BCP/PC) mutant, quantitation of HBsAg (qHBsAg) and platelet counts were independently associated with Ishak fibrosis score on multiple ordinal regression. HBV DNA was undetectable in 88.37% of patients treated with entecavir at week 72, while their level of HBcrAg was still detectable. A greater reduction in post-treatment HBcrAg concentration was associated with the regression of hepatic fibrosis and histological improvement. HBcrAg concentration > 6.33 log IU/mL at baseline and logarithmic reduction > 1.03 log IU/mL at week 72 were associated with a higher chance of regression of liver fibrosis and histological improvement, respectively.

CONCLUSION

HBcrAg level is associated with liver fibrosis progression. HBcrAg is an excellent monitor of hepatic histological changes, especially in CHB patients treated with nucleoside analogs.

Profile and value of FIB-4 in patients with dual chronic hepatitis C and B

BACKGROUND AND AIMS

Patients with chronic hepatitis B virus (HBV) or hepatitis C virus (HCV) infection are at risk of developing adverse outcomes. Coinfection with both viruses may further increase the risk. Currently, little is known about the role of fibrosis-4 (FIB-4) index, a simple liver fibrosis stage biomarker, in predicting the clinical outcomes.

METHODS

We retrospectively enrolled 152 non-cirrhotic patients with dual chronic HCV and HBV infection: 56 patients received pegylated interferon/ribavirin therapy, while 96 patients remained untreated. The association between the FIB-4 index and the incidence of liver cirrhosis and hepatocellular carcinoma (HCC) was explored.

RESULTS

After a 9.88-year follow-up, the incidence of hepatitis B surface antigen seroclearance was 4.97 (95% confidence interval: 3.13-7.89) per 100 person-years in the treated group and was 1.77 (1.10-2.85) in the untreated group. Of the treated group, only three and six patients developed HCC and liver cirrhosis, respectively, while 17 and 23 patients developed HCC and liver cirrhosis, respectively, in untreated group. Baseline FIB-4 index correlated with the development of liver cirrhosis in multivariable analysis of all subjects. High baseline FIB-4 index (per 1 point increase) in the treated groups was associated with a higher risk of developing liver cirrhosis (P = 0.001) and HCC (P = 0.038) in univariable analysis. FIB-4 index decreased only in the treated group who achieved sustained virological response (n = 34, FIB-4 index decreasing from 1.84 to 1.55).

CONCLUSIONS

In Taiwanese patients coinfected with HCV and HBV, FIB-4 index helps identify patients at risk of developing adverse events, even in patients receiving pegylated interferon/ribavirin therapy.

Insights From Deep Sequencing of the HBV Genome-Unique, Tiny, and Misunderstood

Hepatitis B virus (HBV) is a unique, tiny, partially double-stranded, reverse-transcribing DNA virus with proteins encoded by multiple overlapping reading frames. The substitution rate is surprisingly high for a DNA virus, but lower than that of other reverse transcribing organisms. More than 260 million people worldwide have chronic HBV infection, which causes 0.8 million deaths a year. Because of the high burden of disease, international health agencies have set the goal of eliminating HBV infection by 2030. Nonetheless, the intriguing HBV genome has not been well characterized. We summarize data on the HBV genome structure and replication cycle, explain and quantify diversity within and among infected individuals, and discuss advances that can be offered by application of next-generation sequencing technology. In-depth HBV genome analyses could increase our understanding of disease pathogenesis and allow us to better predict patient outcomes, optimize treatment, and develop new therapeutics.

Taiwan consensus statement on the management of chronic hepatitis B

The experts of Taiwan Association for the Study of Liver (TASL) have actively participated and led the guidelines on hepatitis B virus (HBV) management by Asian Pacific Association for the Study of Liver (APASL) which is the first international association for the study of liver to publish the statement on HBV management before. However, there are more and more new data on the natural history and treatment of HBV infection in the past decade. These include new application of an old biomarker (quantitative HBsAg), clinical significance of HBV genotype and naturally occurring mutations, the role of non-invasive examination in evaluating severity of hepatic fibrosis, clinical significance of outcome calculators, new drug or new combination strategies towards more effective therapy and organ transplantation including liver and non-liver transplantation. It is time to publish the guidelines on HBV management of Taiwan. Hence, TASL have conducted an expert meeting to review, to discuss and to debate the relevant literatures, followed by draft the manuscript of HBV management guidelines and recommendations. The guidelines include general management, indications for fibrosis assessment, time to start or stop drug therapy, choice of drug to initiate therapy, when and how to monitor the patients during and after stopping drug therapy. Recommendations on the therapy of patients in special circumstances, including women in childbearing age, patients with antiviral drug resistance, concurrent viral infection, hepatic decompensation, patient receiving immune suppression or chemotherapy and patients in the setting of liver transplantation and hepatocellular carcinoma, are also included.

Chronic hepatitis B virus infection

Chronic hepatitis B virus infection is a global public health threat that causes considerable liver-related morbidity and mortality. It is acquired at birth or later via person-to-person transmission. Vaccination effectively prevents infection and chronic hepatitis B virus carriage. In chronically infected patients, an elevated serum hepatitis B virus DNA concentration is the main risk factor for disease progression, although there are other clinical and viral parameters that influence disease outcomes. In addition to liver biochemistry, virological markers, and abdominal ultrasonography, non-invasive assessment of liver fibrosis is emerging as an important assessment modality. Long-term nucleos(t)ide-analogue therapy is safe and well tolerated, achieves potent viral suppression, and reduces the incidence of liver-related complications. However, a need to optimise management remains. Promising novel therapies are at the developmental stage. With current vaccines, therapies, and an emphasis on improving linkage to care, WHO's goal of eliminating hepatitis B virus as a global health threat by 2030 is achievable.

Natural History of Chronic Hepatitis B Virus Infection in Ahvaz City, Iran

Objective: A long persistent of Chronic Hepatitis B (CHB) infection may develop liver cirrhosis or hepatocellular carcinoma (HCC) and about one million people die due to HBV -related liver cancer and end-stage liver disease annually worldwide. The natural history of CHB phases comprises four phases: immune tolerant (HBeAg detectable and ALT (Alanine Transaminase) normal, HBeAg-positive immune active (HBeAg detectable, anti-HBe antibodies undetectable and ALT persistently elevated), HBeAg-negative immune active (HBeAg undetectable, anti-HBe antibodies present and ALT persistently elevated), inactive carrier (HBeAg undetectable, anti-HBe antibodies present and ALT normal). The evaluation of chronic hepatitis B phases is a crucial to manage the burden of disease and limit the development of associated complications, such as cirrhosis and hepatocellular carcinoma (HCC). Thus this study conducted to evaluate the natural history of HBV infection in patients with chronic HBV infection in Ahvaz city, Iran. Methods: In this study, 71 non-treated CHB individuals were recruited including 44 (62%) males and 27(38%) females. The sera were tested for HBV markers, HBsAg, HBcIgG, HBeAg, and HBeAb. ALT assay and HBV viral load were carried out for each CHB individual. Results: Based on the analysis of serological, ALT status and viral load, the results showed: immune tolerance 5(7%), eAg+ Immune Clearance 14(19.7%), eAg- Immune Clearance 29 (40.84%) and Inactive Carrier 23 (32.39%). The HBeAg seroconversion was observed in a male age 18 year. Conclusion: The results of the natural history of individuals with chronic hepatitis B phases CHB shows immune tolerance (7%), eAg+ Immune Clearance (19.7%), eAg- Immune Clearance (40.84%) and Inactive Carrier (32.39%). To prevent the consequence of CHB infection, an individual in immune tolerance phase should be tested periodically for ALT level, HBV markers, HBsAg, HBcIgG, HBeAg, HBeAb and HBV viral load. Then decision-making therapy can be applied for CHB patients at early stage of immune clearance.

Development of a fibrosis index including hepatitis B virus basal core promoter A1762T mutation for pretherapeutic evaluation

BACKGROUND AND AIM

Commonly used non-invasive fibrosis scores usually included serum transaminase levels in the equations, including Aspartate transaminase to Platelet Ratio Index (APRI) and fibrosis-4 (FIB-4). Transaminases fluctuated significantly in chronic hepatitis B patients with exacerbations, leading to unsteady score values. As such, here, we aim to develop a transaminase-free score suitable for pretherapeutic evaluation of fibrosis stages.

METHODS

Firstly, 1082 treatment-naïve chronic hepatitis B patients were enrolled and divided into modeling (n = 541) and verification (n = 541) cohorts. Secondly, 265 patients having received liver biopsy, with known Ishak fibrosis stages, were included for independent correlation.

RESULTS

Cross-sectional analysis of 1082 patients revealed age-dependent variation of association between virological factors and cirrhosis. A fibrosis score including Anti-hepatitis B e antibody, Basal core promoter (BCP) A1762T mutation, and Platelet count Index (named ABPI) was derived from the modeling cohort. ABPI performed better than APRI and FIB-4 in the verification cohort for identifying cirrhotic patients (comparison of area under the receiver operating characteristic curves: ABPI vs APRI and FIB-4 = 0.785 vs 0.563 [P < 0.001] and 0.700 [P = 0.026], respectively). The performance of ABPI was even better in young (< 40 years old) hepatitis B patients (area under the receiver operating characteristic curves: 0.856 vs 0.402 [P < 0.001] and 0.599 [P = 0.009], respectively). Finally, in the independent cohort of 265 patients with known Ishak fibrosis stages, it was found that ABPI effectively distinguished between Ishak fibrosis stages 3 and > 3 and between 4 and > 4 (P < 0.001 for each).

CONCLUSIONS

We developed a transaminase-free fibrosis score (ABPI) utilizing basal core promoter A1762T data, which outperformed APRI and FIB-4.

Fibrosis-4 index predicts cirrhosis risk and liver-related mortality in 2075 patients with chronic HBV infection

BACKGROUND

Fibrosis-4 index (FIB-4) is a surrogate marker for hepatic fibrosis in hepatitis B virus (HBV) carriers.

AIM

To investigate whether FIB-4 index stratifies the risks of adverse liver events.

METHODS

A total of 2075 treatment-naïve, noncirrhotic the patients with chronic HBV infection were included. Most of them (82.1%) were HBeAg-negative patients and their baseline FIB-4 levels were explored to stratify the risks of cirrhosis, cirrhosis-related complications and liver-related mortality.

RESULTS

During a mean follow-up period of 15.47 years, we found a higher baseline FIB-4 index was associated with increased incidence rates of cirrhosis in addition to the common host and viral factors. Patients with FIB-4 >1.29, compared to those with FIB-4 <1.29, were associated with increased risks of cirrhosis, cirrhosis-related complications and liver-related mortality with the hazard ratio (95% confidence interval) of 6.19 (4.76-8.05), 6.88, (3.68-12.86) and 7.79, (4.54-13.37) respectively. Within the first 3 years of follow-up, FIB-4 remained stable and its kinetics were consistently associated with the develoopment of adverse liver events. Furthermore, FIB-4 index of 1.29 was able to stratify all the risks of adverse liver events even in HBeAg-negative patients with a low risk of disease progression (HBV DNA <2000 IU/mL, HBsAg <1000 IU/mL and ALT <40 U/L). Only 1 patient with FIB-4 index <1.29 developed cirrhosis but not other events within 15 years of follow-up.

CONCLUSIONS

In noncirrhotic patients with chronic HBV infection, a higher FIB-4 index was associated with increased risks of adverse liver events. FIB-4 index <1.29 is useful for the prediction of the lowest risks of disease progression.

Anti-viral therapy can be delayed or avoided in a significant proportion of HBeAg-negative Caucasian patients in the Grey Zone

BACKGROUND

Grey Zone (GZ) is an ill-defined situation including patients falling between inactive carrier (IC) state and HBeAg-negative chronic hepatitis B (HBeAg-negative CHB).

AIMS

To assess the long-term outcomes of GZ patients compared to IC in the absence of treatment.

METHODS

Retrospective analysis of 287 IC and GZ HBeAg-negative patients. Patients were classified into 4 groups at baseline: HBV-DNA <2000 IU/mL and ALT <40 U/L (IC), HBV-DNA <2000 IU/mL and ALT 40-80 U/L (GZ-1), HBV-DNA 2000-20 000 IU/mL and ALT <40 U/L (GZ-2) or ALT 40-80 U/L (GZ-3). Data were also analysed using AASLD ALT criteria.

RESULTS

After a median follow-up of 8.2 (5-19) years, HBsAg loss occurred in about 15% ICs or GZ patients. Transition into IC state occurred in 40% of GZ patients. DNA fluctuations >2000 IU/mL correlated inversely with transition into IC and HBsAg loss. HBsAg levels were significantly lower in ICs than in GZ patients (338 IU/mL [20-3269] vs 5763 IU/mL [2172-17 754]; P < 0.05). Among the latter group, there was an increasing gradient of HBsAg levels from GZ-1 to GZ-3 patients (P < 0.05). HBeAg-negative CHB occurred in only 18 (6.3%) GZ patients. No patient developed cirrhosis nor advanced fibrosis. ALT/HBV-DNA fluctuations and HBeAg-negative CHB development were more frequent in genotype B/C patients, whereas HBsAg loss occurred only in genotype A/D patients.

CONCLUSIONS

Most Caucasian GZ patients present excellent long-term outcomes in the absence of treatment, with a high rate of HBsAg loss and low rate of progression to HBeAg-negative CHB. HBV-genotyping and HBsAg levels could help to predict outcomes and better classify GZ patients.

Hepatitis B virus core-related antigen levels predict progression to liver cirrhosis in hepatitis B carriers

BACKGROUND AND AIM

Several hepatitis B virus (HBV) markers have been identified as risk factors for progression to liver cirrhosis in patients with chronic HBV infection. The predictive impact of HBV markers on progression to cirrhosis in HBV carriers was clarified.

METHODS

A total of 529 hepatitis B e antigen seroconverters with fibrosis-4 (FIB-4) index ≤ 3.6 not on nucleos(t)ide analogue therapy were included. Univariate and multivariate analyses of associations between HBV markers and progression to cirrhosis were performed. In addition, the hazard ratio (HR) spline curves for continuous HBV markers were compared.

RESULTS

Eighty-four patients progressed to cirrhosis (FIB-4 index > 3.6) during the follow-up period. Hepatitis B surface antigen (HBsAg), HBV DNA, HBV core-related antigen (HBcrAg), and basal core promoter status, but not genotype and precore status, were significantly associated with progression to cirrhosis in univariate Cox proportional hazards models. Multivariate Cox proportional hazards models adjusted for HBV genotype, HBsAg, HBV DNA, HBcrAg, precore status, and basal core promoter status indicated that HBsAg ≥ 3.0 log IU/mL (HR, 0.53; 95% confidence interval [CI], 0.30-0.94) and HBcrAg ≥ 3.7 log U/mL (HR, 3.28; 95% CI, 1.60-6.75) are independently associated with progression to cirrhosis. In the HR spline curve analysis, HR and 95% CI gradually increased as HBcrAg levels increased. Conversely, HRs and 95% CIs for HBsAg and HBV DNA did not show this tendency as their levels increased.

CONCLUSIONS

Elevated HBcrAg levels in HBV carriers increases the risk for progression to cirrhosis. HBcrAg is an excellent predictor of the development of cirrhosis.

Can quantitative hepatitis B surface antigen levels predict the severity of liver disease in genotype E Patients?

The utility of quantitative Hepatitis B surface antigen (qHBsAg) level as a marker of chronic hepatitis B (CHB)-related liver damage is not fully delineated, but is becoming increasingly relevant. Quantitative HBsAg levels are linked with progression of liver disease in HBeAg-negative genotype B and C patients, but it is not clear whether this is consistent across all HBV genotypes. In this single-centre, cross-sectional observational study, we evaluated whether qHBsAg levels can predict the severity of liver disease in genotype E patients. Demographic characteristics, viral, biochemical markers and qHBsAg levels were assessed at time of liver biopsy [all HBV DNA>2000 IU/mL and/or abnormal alanine transaminase (ALT)]. Patients were divided into three groups according to the severity of fibrosis on biopsy: mild (F0-1), moderate (F2-4), severe (F5-6) liver disease and into two groups according to the NI grading, low (NI 0-3) and high inflammation (NI ≥4). A total of 259 HBeAg-negative CHB treatment-naive genotype E patients were studied. The median age of this cohort was 38 years, and 61% were males. Advanced (severe) fibrosis patients had higher ALT, HBV DNA, and lower HBsAg level and qHBsAg/DNA ratio. Patients with NI ≥4 had higher ALT, HBV DNA, but lower qHBsAg/DNA ratio. There was no correlation between HBsAg and HBV DNA levels. Quantitative HBsAg levels were lower in more advanced liver fibrosis. There was no correlation between qHBsAg and HBV DNA levels. This may reflect discordance between viral replication and transcriptional activity or differential HBsAg expression in HBeAg-negative genotype E patients with advanced liver disease.

Viral Factors Affecting the Clinical Outcomes of Chronic Hepatitis B

Chronic hepatitis B (CHB) exhibits a variety of clinical outcomes, ranging from spontaneous resolution of hepatitis B to severe adverse consequences, including the development of cirrhosis, hepatic failure, and hepatocellular carcinoma. The heterogeneous clinical courses of chronic hepatitis B virus (HBV) infection reflect the complex host-virus interactions, and point to the difficulty and necessity of identifying the patients at risk. With the advance of HBV virology, several viral factors have been found to be associated with the long-term clinical outcomes of CHB patients. Different viral factors probe different aspects of CHB. Integration of these viral factors may help to determine the disease state of patients more accurately, and identify the patients who require timely antiviral therapy to prevent the development of detrimental clinical outcomes. In this article, we will introduce the conventional and emerging viral factors that are associated with clinical outcomes and discuss their utility in a clinical setting.

Deep sequencing shows that HBV basal core promoter and precore variants reduce the likelihood of HBsAg loss following tenofovir disoproxil fumarate therapy in HBeAg-positive chronic hepatitis B

OBJECTIVE

Hepatitis B e antigen (HBeAg) seroconversion and hepatitis B surface antigen (HBsAg) loss are important clinical outcomes for patients with chronic hepatitis B (CHB) treated with antiviral therapy. To date, there have been few studies that have evaluated viral sequence markers predicting serological response to nucleos(t)ide analogue (NA) treatment.

DESIGN

We used next-generation sequencing (NGS) and quantitative HBV serology (HBeAg and HBsAg) to identify viral sequence markers associated with serological response to long-term tenofovir disoproxil fumarate therapy among HBeAg-positive patients. In the GS-US-174-0103 study, approximately half the patients seroconverted to anti-HBe by week 192 and 11% of patients exhibited HBsAg loss, the closest outcome to functional cure. The frequency of HBV variants that have previously been associated with HBV clinical outcomes was evaluated. HBV viral diversity in baseline sequences generated by NGS was calculated using Shannon entropy.

RESULTS

NGS analysis of HBV sequences from 157 patients infected with genotypes A to D showed the frequency of variants in the basal core promoter (BCP) and precore (PC) regions varied by genotype and that these mutations were associated with the absence of HBsAg loss. This was the case even when mutations were present at frequencies below the threshold of detection by population sequencing. Increased viral diversity across the HBV genome as determined by NGS was also associated with reduced likelihood of HBsAg loss.

CONCLUSION

Patients with detectable BCP and/or PC variants and higher viral diversity have a lower probability of HBsAg loss during long-term NA therapy. Strategies to achieve functional cure of HBV infection through combination therapy should consider using NGS to stratify patients according to BCP/PC sequence. Consideration should also be given to earlier initiation of therapy prior to the emergence of BCP/PC variants.

TRIAL REGISTRATION NUMBER

NCT00116805; Post result.

Fibrosis-4 Index Helps Identify HBV Carriers With the Lowest Risk of Hepatocellular Carcinoma

OBJECTIVES

Several viral and host risk factors have been used to predict risks of hepatocellular carcinoma (HCC) in patients with chronic infection of hepatitis B virus (HBV). However, little is known whether fibrosis-4 (FIB-4) index, a liver fibrosis biomarker, helps identify non-cirrhotic patients with the lowest HCC risk.

METHODS

A total of 2075 treatment-naive Taiwanese patients with chronic HBV infection were followed for an average period of 16.02 years. None of them had liver cirrhosis at baseline. We explored whether a low FIB-4 index complements the favourable predictors to defines patients with the lowest HCC risk. The finding was validated in 532 non-cirrhotic patients receiving long-term nucleos(t)ide analogue (NUC) treatment with suppressed viral replication.

RESULTS

A total of 137 treatment-naive and 10 NUC-treated patients developed HCC, respectively. We found that HCC risk started to increase when baseline FIB-4 index >1.29 in the treatment-naive cohort. Patients with FIB-4 >1.29, compared to those with FIB-4 <1.29, were associated with a higher risk of HCC with hazards ratio of 5.56 (95% confidence interval: 3.93-7.86). More importantly, among patients with low viral load (HBV DNA level <2,000 IU/ml), baseline FIB-4 index helped stratify different HCC risks such that none of 326 HBeAg-negative patients with FIB-4 index <1.29, ALT level <40 U/l, and HBsAg level <1,000 IU/ml developed HCC. In addition, the patients with the FIB-4 index <1.29 consistently had the lowest HCC risks in the validation cohort receiving long-term NUC treatment.

CONCLUSIONS

In non-cirrhotic patients with chronic HBV infection, FIB-4 index <1.29 complements the existing clinical profile to define patients with the lowest HCC risk.

A putative hepatitis B virus splice variant associated with chronic hepatitis and liver cirrhosis

Hepatitis B virus (HBV) pre-S deletion was associated with chronic hepatitis (CH) and liver cirrhosis (LC); however, the type of pre-S deletion associated with these conditions and the mechanism of the generation of pre-S deletion remain unknown. Here, pre-S sequences from asymptomatic carriers (ASCs) and carriers with CH or LC were analyzed. The results indicated that deletion in the S promoter and the C-terminal half of the pre-S1 region was more frequent in CH and LC patients than in ASCs. RNA splicing analysis revealed that one type of pre-S1 deletion mutant, termed spPS1, was derived from splicing. This variant was associated with CH (12.7% vs. 1.8%, P = 0.06) and LC (14.5% vs. 1.8%, P = 0.032) when compared with ASC. In conclusion, spPS1, a putative splice variant; S promoter deletion mutant; and deletion in the C-terminal half of the pre-S1 region were closely associated with CH and LC development.

Compartmental HBV evolution and replication in liver and extrahepatic sites after nucleos/tide analogue therapy in chronic hepatitis B carriers

BACKGROUND

Hepatitis B virus (HBV) variants are associated with nucleos/tide analogue (NA) response and liver disease but it is unknown whether NA influences extrahepatic HBV persistence.

OBJECTIVES

To investigate HBV replication and genetic evolution in hepatic and extrahepatic sites of chronic hepatitis B (CHB) before and after NA therapy.

STUDY DESIGN

A total of 13 paired plasma, peripheral blood mononuclear cells (PBMC), were collected from chronic HBV carriers at baseline and after a median 53 weeks NA therapy as well as liver biopsy (N=7 baseline, N=5 follow-up). HBV covalently closed circular DNA (cccDNA) and messenger (m) RNA in liver and PBMC were analyzed. HBV polymerase (P)/surface (S), basal core promoter (BCP)/pre-core (PC)/C gene clonal sequencing was done in plasma, peripheral blood mononuclear cells (PBMC), and liver.

RESULTS

Compare to baseline, at ∼53 weeks follow-up, there was no significant change in HBV cccDNA levels in liver (0.2-0.08 copies/hepatocyte, p>0.05) or in PBMC 0.003-0.02 copies/PBMC, p>0.05), and HBV mRNA remained detectable in both sites. At baseline, BCP variants were higher in PBMC vs. liver and plasma. After therapy, drug resistant (DR) and immune escape (IE) variants increased in liver but IE and PC variants were more frequent in PBMC. HBV P/S diversity was significantly higher in PBMC compared to plasma.

CONCLUSION

Continuous HBV replication occurs in liver and PBMC and shows compartmentalized evolution under selective pressure of potent NA therapy.

Mutations in basal core promoter is associated with significant fibrosis in both HBeAg positive and negative treatment-naïve chronic hepatitis B

AIM

Assessment of liver fibrosis is important for the decision of whether to administrate antiviral treatment in chronic Hepatitis B (CHB) patients. The objective was to investigate the relationship between clinical factors and fibrosis, identify predictors of significant fibrosis in Chinese CHB patients.

METHODS

Two hundred and seventy-four treatment-naïve CHB patients (208 HBeAg-positive and 66 HBeAg-negative) who performed transient elastography were consecutively included. We assessed ALT, HBsAg, HBeAg, HBV-DNA, HBV genotype and precore (PC)/basal core promoter (BCP) variants and liver stiffness measurement (LSM) values.

RESULTS

One hundred and nine patients (39.78%) had significant fibrosis (F≥2, include those with liver cirrhosis). On univariate analysis, significant fibrosis was associated with older age (P<0.001), high ALT levels (P=0.003), lower HBsAg levels (P<0.001), lower HBV DNA levels (P<0.001), HBeAg negative (P<0.001), presence of BCP (P<0.001) and combined BCP/PC mutations (P=0.001). Multivariate logistic regression analysis showed that the strongest independently associated predictors of significant fibrosis (F≥2) were the presence of HBV BCP mutations (P<0.001) and older age (P<0.001), followed by presence of lower HBsAg (P<0.001), higher ALT levels (P=0.006), PC mutations (P=0.011). The diagnostic accuracy of the combination (age, ALT, HBsAg, BCP/PC variants) model with an area under the receiver-operating characteristic curve of 0.819 (cut-off value was 0.349, P<0.001, 95% CI 0.731-0.914) in predicting significant fibrosis.

CONCLUSIONS

We identified four independent risk factors (age, ALT, HBsAg, HBV BCP/PC variants) in predicting significant fibrosis. HBV BCP variants was the strongest predictor of significant fibrosis. The combination of these four variables may facilitate the assessment and management of fibrosis in HBV infected patients.