Hepatitis B virus genotype C takes a more aggressive disease course than hepatitis B virus genotype B in hepatitis B e antigen-positive patients

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.

A novel nomogram for predicting HBeAg seroclearance in HBeAg-positive chronic hepatitis B patients treated with nucleos(t)ide analogues

INTRODUCTION AND OBJECTIVES

Seroclearance of hepatitis B e antigen (HBeAg) is an important treatment goal for patients with chronic hepatitis B (CHB). This study developed a nomogram for predicting HBeAg seroclearance in CHB patients treated with nucleos(t)ide analogues (NAs).

PATIENTS AND METHODS

Five hundred and sixty-nine CHB patients treated with NAs from two institutions between July 2016 to November 2021 were retrospectively included. One institution served as the training set (n = 374) and the other as the external validation set (n = 195). A predictive nomogram was established based on cox regression analysis.

RESULTS

The overall HBeAg seroclearance rates were 27.3 and 21.5 % after the median follow-up of 100.2 weeks and 65.1 weeks in the training set and validation set, respectively. In the training set, baseline aspartate aminotransferase, gamma-glutamyl transpeptidase, HBeAg, and hepatitis B core antibody levels were independently associated with HBeAg seroclearance and were used to establish the HBEAg SeroClearance (ESC)-nomogram. The calibration curve revealed that the ESC-nomogram had a good agreement with actual observation. The ESC-nomogram showed relatively high accuracy for predicting 48 weeks, 96 weeks, and 144 weeks of HBeAg seroclearance in the training set (AUCs: 0.782, 0.734 and 0.671) and validation set (AUCs: 0.699, 0.718 and 0.689). The patients with high ESC-nomogram scores (≥ 79.51) had significantly higher cumulative incidence of HBeAg seroclearance and seroconversion than patients with low scores (< 79.51) in both sets (P < 0.01).

CONCLUSIONS

The novel ESC-nomogram showed good performance for predicting antiviral efficacy in HBeAg-positive CHB patients with NAs treatment.

Five-year on-treatment variables-based PPACS model predicts subsequent hepatocellular carcinoma in entecavir/tenofovir-treated patients

Considering the lower risk of hepatocellular carcinoma (HCC) in chronic hepatitis B (CHB) patients receiving long-term potent antiviral therapy, models predicting HCC after 5 years of therapy are needed. We conducted a multicenter retrospective cohort study to construct and validate a model predicting HCC after 5 years of entecavir (ETV) or tenofovir (TFV) therapy for CHB. The endpoint was HCC after 5 years of ETV/TFV therapy. Information on age, sex, liver cirrhosis (assessed by diagnosis code and confirmed by clinical findings) and type of antiviral agent was obtained at baseline (initiation of ETV/TFV). Laboratory values were collected at baseline and 5 years. Risk factors for HCC were identified in the training set and the final prediction model was validated using the test set. Among 7542 patients, 345 (4.6%) developed HCC after 5 years of ETV/TFV therapy. HCC risk after 5 years of ETV/TFV therapy was increased by 4-fold in patients with liver cirrhosis than in those without cirrhosis at baseline. Furthermore, Platelet counts and Prothrombin time at 5 years, Age at baseline and Sex were associated with risk of HCC and were incorporated into a prediction model, PPACS. PPACS showed a good performance with a time-dependent area under the curve of 0.80 (95% confidence interval, 0.75-0.85) at 8-year of ETV/TFV therapy, a Brier score of 0.031 and an integrated Brier score of 0.006 in the test set. In conclusion, the PPACS model provides a reliable assessment of HCC risk after 5 years of ETV/TFV therapy (https://ppacs.shinyapps.io/shiny_app_up/).

CRISPR-Cas Systems: Programmable Nuclease Revolutionizing the Molecular Diagnosis

CRISPR-Cas system has evolved as a highly preferred genetic engineering tool to perform target gene manipulation via alteration of the guide RNA (gRNA) sequence. The ability to recognize and cleave a specific target with high precision has led to its applicability in multiple frontiers pertaining to human health and medicine. From basic research focused on understanding the molecular basis of disease to translational approach leading to early and precise disease diagnosis as well as developing effective therapeutics, the CRISPR-Cas system has proved to be a quite versatile tool. The coupling of CRISPR-Cas mediated cleavage with isothermal amplification (ISA) of target DNA, followed by a read-out using fluorescent or colorimetric reporters appears quite promising in providing a solution to the urgent need for nucleic acid-based point-of-care diagnostic. Hence, it has been recognized as a highly sophisticated molecular diagnostic tool for the detection of disease-specific biomarkers not limited to nucleic acids-based detection but also of non-nucleic acid targets such as proteins, exosomes, and other small molecules. In this review, we have presented salient features and principles of class 2 type II, V, and VI CRISPR-Cas systems represented by Cas9, Cas12, and Cas13 endonucleases which are frequently used in molecular diagnosis. The article then highlights different medical diagnostic applications of CRISPR-Cas systems focusing on the diagnosis of SARS-CoV-2, Dengue, Mycobacterium tuberculosis, and Listeria monocytogenes. Lastly, we discuss existing obstacles and potential future pathways concerning this subject in a concise manner.

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.

Global prevalence and molecular characteristics of three clades within hepatitis B virus subgenotype C2: Predominance of the C2(3) clade in South Korea

Hepatitis B Virus (HBV) genotypes reflect geographic, ethical or clinical traits and are currently divided into 10 genotypes (A–J). Of these, genotype C is mainly distributed in Asia, is the largest group and comprises more than seven subgenotypes (C1–C7). Subgenotype C2 is divided into three phylogenetically distinct clades, C2(1), C2(2), and C2(3), and is responsible for most genotype C infections in three East Asian nations, including China, Japan, and South Korea, which are major HBV endemic areas. However, despite the significance of subgenotype C2 with regard to clinical or epidemiologic aspects, its global distribution and molecular characteristics remain largely unknown. Here, we analyze the global prevalence and molecular characteristics between 3 clades within subgenotype C2 using 1,315 full genome sequences of HBV genotype C retrieved from public databases. Our data show that almost all HBV strains from South Korean patients infected with genotype C belong to clade C2(3) within subgenotype C2 [96.3%] but that HBV strains from Chinese or Japanese patients belong to diverse subgenotypes or clades within genotype C, suggesting clonal expansion of a specific HBV type, C2(3), among the Korean population. Our genome sequence analysis indicated a total of 21 signature sequences specific to the respective clades C2(1), C2(2), and C2(3). Of note, two types of four nonsynonymous C2(3) signature sequences, sV184A in HBsAg and xT36P in the X region, were detected in 78.9 and 82.9% of HBV C2(3) strains, respectively. In particular, HBV strains C2(3) versus C2(1) and C2(2) show a higher frequency of reverse transcriptase mutations related to nucleot(s)ide analog (NA) resistance, including rtM204I and rtL180M, suggesting an increased possibility of C2(3) infection in those with NA treatment failure. In conclusion, our data show that HBV subgenotype C2(3) is extremely prevalent in Korean patients with chronic HBV infection, which is distinct from two other East Asian nations, China and Japan, where diverse subgenotypes or clades within genotype C coexist. This epidemiologic trait might affect distinct virological and clinical traits in chronic HBV patients in Korea, where exclusively C2(3) infection is predominant.

Significant histological disease of patients with chronic hepatitis B virus infection in the grey zone

BACKGROUND

Many patients with chronic hepatitis B (CHB) do not meet the definitions of the traditional natural phases and are classified as being in the grey zone (GZ).

AIMS

To investigate liver histology, and to establish a management strategy for patients with CHB in the GZ.

METHODS

This study included 1043 patients with CHB who underwent liver biopsy. Phases of natural history were determined according to the AASLD 2018 hepatitis B guidance. CHB patients in the GZ were divided into HBeAg-positive, normal ALT and HBV DNA ≤10⁶  IU/ml (GZ-A); HBeAg-positive, elevated ALT and HBV DNA ≤2 × 10⁴  IU/ml (GZ-B); HBeAg-negative, normal ALT and HBV DNA ≥2 × 10³  IU/ml (GZ-C) and HBeAg-negative, elevated ALT and HBV DNA ≤2 × 10³  IU/ml (GZ-D). Significant histological disease was defined as liver inflammation ≥G2 and/or liver fibrosis ≥S2.

RESULTS

Two hundred and forty two (23.2%) patients were in the GZ. Approximately 72.7% had significant histological disease. HBeAg-positive GZ CHB patients had a higher proportion of significant histological disease than HBeAg-negative GZ patients (91.1% vs. 68.5%, p = 0.002). GZ-D (42.6%) was the dominant category, followed by GZ-C (38.8%), GZ-A (10.3%) and GZ-B (8.3%). The highest proportion of significant histological disease was observed patients in GZ-B (100.0%), followed by GZ-A (84.0%), GZ-D (69.9%) and GZ-C (67.0%). Prothrombin time (PT) was an independent risk factor of significant histological disease in the HBeAg-negative GZ.

CONCLUSIONS

Over 70% of GZ CHB patients had significant histological disease. We recommend antiviral treatment for HBeAg-positive and HBeAg-negative GZ CHB patients with high PT.

Molecular clones of genetically distinct hepatitis B virus genotypes reveal distinct host and drug treatment responses

Background & Aims

HBV exhibits wide genetic diversity with at least 9 genotypes (GTs), which differ in terms of prevalence, geographic distribution, natural history, disease progression, and treatment outcome. However, differences in HBV replicative capacity, gene expression, and infective capability across different GTs remain incompletely understood. Herein, we aimed to study these crucial aspects using newly constructed infectious clones covering the major HBV GTs.

Methods

The replicative capacity of infectious clones covering HBV GTs A-E was analyzed in cell lines, primary hepatocytes and humanized mice. Host responses and histopathology induced by the different HBV GTs were characterized in hydrodynamically injected mice. Differences in treatment responses to entecavir and various HBV capsid inhibitors were also quantified across the different genetically defined GTs.

Results

Patient-derived HBV infectious clones replicated robustly both in vitro and in vivo. GTs A and D induce more pronounced intrahepatic and proinflammatory cytokine responses which correlated with faster viral clearance. Notably, all 5 HBV clones robustly produced viral particles following transfection into HepG2 cells, and these particles were infectious in HepG2-NTCP cells, primary human hepatocytes and human chimeric mice. Notably, GT D virus exhibited higher infectivity than GTs A, B, C and E in vitro, although it was comparable to GT A and B in the human liver chimeric mice in vivo. HBV capsid inhibitors were more readily capable of suppressing HBV GTs A, B, D and E than C.

Conclusions

The infectious clones described here have broad utility as genetic tools that can mechanistically dissect intergenotypic differences in antiviral immunity and pathogenesis and aid in HBV drug development and screening.

Lay summary

The hepatitis B virus (HBV) is a major contributor to human morbidity and mortality. HBV can be categorized into a number of genotypes, based on their specific genetic make-up, of which 9 are well known. We isolated and cloned the genomes of 5 of these genotypes and used them to create valuable tools for future research on this clinically important virus.

Treatment Algorithm for Managing Chronic Hepatitis B Virus Infection in the United States: 2021 Update

BACKGROUND & AIMS

Chronic hepatitis B (CHB) infection remains the most frequent etiology of hepatocellular carcinoma globally as well as a major cause of cirrhosis. Despite vaccination, substantial numbers of persons have already been infected with hepatitis B virus and remain at risk of progressive liver disease.

METHODS

In 2004, a CHB management algorithm was developed by a panel of North American hepatologists, which was subsequently updated in 2006, 2008, and 2015. Since the most recent version, several developments have altered the management of CHB. Tenofovir alafenamide, with a more favorable safety profile than tenofovir disoproxil fumarate, has been introduced as an initial antiviral choice as well as an alternative for long-term therapy. Quantitation of hepatitis B surface antigen is becoming more widely available in clinical practice, with implications for monitoring response to treatment. Additionally, there has been a shift in how the natural history of CHB is perceived, as newer evidence has challenged the concept that during the immunotolerant phase of infection disease progression is not a concern. Finally, recent analyses indicate that in the United States, the average age of patients with CHB has increased, implying that the presence of comorbidities, including metabolic liver disease, increasing use of biologics associated with aging will increasingly affect disease management.

RESULTS

This updated algorithm is intended to serve as a guide to manage CHB while new antiviral strategies are developed.

CONCLUSIONS

Recommendations have been based on evidence from the scientific literature, when possible, as well as clinical experience and consensus expert opinion. Points of continued debate and areas of research need are also described.

Association of Coexistent Hepatitis B Surface Antigen and Antibody With Severe Liver Fibrosis and Cirrhosis in Treatment-Naive Patients With Chronic Hepatitis B

IMPORTANCE

Coexistence of hepatitis B surface antigen (HBsAg) and antibody against HBsAg (anti-HBs) constitutes an atypical serological profile in chronic hepatitis B virus infection, and the association between coexistent HBsAg and anti-HBs with severe liver fibrosis and cirrhosis in patients with chronic hepatitis B (CHB) remains unclear.

OBJECTIVE

To investigate the association of coexistent HBsAg and anti-HBs with severe liver fibrosis and cirrhosis in patients with CHB.

DESIGN, SETTING, AND PARTICIPANTS

Consecutive treatment-naive patients with CHB from 2 medical institutions in China were enrolled between January 10, 2015, and March 31, 2021. Severe liver fibrosis and cirrhosis were identified using the aspartate transaminase (AST) to platelet ratio index (APRI), the fibrosis index based on 4 factors (FIB-4; factors comprise age, AST level, alanine aminotransferase [ALT] level, and platelet count), transient elastography, or ultrasonography. Data were analyzed from August 1, 2021, to April 15, 2022.

MAIN OUTCOMES AND MEASURES

The primary outcomes were rates of severe liver fibrosis and cirrhosis among patients with vs patients without coexistant HBsAg and anti-HBs. Severe liver fibrosis was defined as an APRI score of 1.5 or higher, a FIB-4 score of 3.25 or higher, or a liver stiffness measurement of 8 kPa or higher; cirrhosis was defined as an APRI score of 2.0 or higher, a FIB-4 score of 6.5 or higher, a liver stiffness measurement of 11 kPa or higher, or ultrasonographic findings suggestive of cirrhosis.

RESULTS

Of 6534 enrolled patients, 4033 patients (61.7%) were male, and the median (IQR) age was 41.0 (33.0-52.0) years. A total of 277 patients (4.2%) had coexistent HBsAg and anti-HBs. Patients with vs without anti-HBs were older (median [IQR], 46.0 [33.0-55.5] years vs 41.0 [33.0-52.0] years) and had a higher proportion of hepatitis B e antigen (HBeAg) positivity (123 of 277 patients [44.4%] vs 2115 of 6257 patients [33.8%]; P < .001), higher ALT levels (median [IQR], 45.1 [24.6-119.0] U/L vs 36.7 [22.0-77.0] U/L; P = .001) and AST levels (median [IQR], 35.0 [23.5-68.4] U/L vs 28.3 [21.6-51.0] U/L; P < .001), and lower platelet counts (median [IQR], 173.0 × 103/μL [129.0-212.5 × 103/μL] vs 185.0 × 103/μL [141.0-224.0 × 103/μL]; P = .004), albumin levels (median [IQR], 4.37 [4.11-4.56] g/dL vs 4.43 [4.17-4.61] g/dL; P = .02), and HBsAg levels (median [IQR], 2.8 log10 [1.6-3.4 log10] IU/mL vs 3.3 log10 [2.6-3.9 log10] IU/mL; P < .001). Compared with patients without anti-HBs, those with anti-HBs had higher APRI scores (median [IQR], 0.5 [0.3-1.4] vs 0.4 [0.3-0.9]; P < .001), FIB-4 scores (median [IQR], 1.4 [0.9-2.6] vs 1.1 [0.7-2.1]; P < .001), and liver stiffness values (median [IQR], 7.5 [6.2-9.8] kPa vs 6.3 [5.2-8.1] kPa; P = .003). Patients with anti-HBs also had higher proportions of severe liver fibrosis (102 of 277 patients [36.8%] vs 1397 of 6207 patients [22.5%]; P < .001) and cirrhosis (87 of 277 patients [31.4%] vs 1194 of 6213 patients [19.2%]; P < .001) compared with patients without anti-HBs. The coexistence of HBsAg and anti-HBs was independently associated with severe liver fibrosis (odds ratio [OR], 2.29; 95% CI, 1.56-3.38; P < .001) and cirrhosis (OR, 1.73; 95% CI, 1.12-2.68; P = .01) in the multivariate analysis. However, the association of coexistent HBsAg and anti-HBs with cirrhosis was only observed in patients with HBeAg negativity (OR, 1.66; 95% CI, 1.05-2.62; P = .03) and not in patients with HBeAg positivity (OR, 1.45; 95% CI, 0.87-2.43; P = .16).

CONCLUSIONS AND RELEVANCE

In this cross-sectional study, the coexistence of HBsAg and anti-HBs was unusual in hepatitis B virus infection and was associated with more advanced liver diseases, such as severe liver fibrosis and cirrhosis, especially among patients with HBeAg negativity. These results suggest that close monitoring for liver fibrosis and cirrhosis is warranted in patients with CHB who have this serological profile.

Different evolutionary dynamics of hepatitis B virus genotypes A and D, and hepatitis D virus genotypes 1 and 2 in an endemic area of Yakutia, Russia

Background

The geographic distribution of the hepatitis B virus (HBV) and the hepatitis D virus (HDV) genotypes is uneven. We reconstructed the temporal evolution of HBV and HDV in Yakutia, one of the regions of Russia most affected by HBV and HDV, in an attempt to understand the possible mechanisms that led to unusual for Russia pattern of viral genotypes and to identify current distribution trends.

Methods

HBV and HDV genotypes were determined in sera collected in 2018–2019 in Yakutia from randomly selected 140 patients with HBV monoinfection and 59 patients with HBV/HDV. Total 86 HBV and 88 HDV genomic sequences isolated in Yakutia between 1997 and 2019 were subjected to phylodynamic and philogeographic Bayesian analysis using BEAST v1.10.4 software package. Bayesian SkyGrid reconstruction and Birth–Death Skyline analysis were applied to estimate HBV and HDV population dynamics.

Results

Currently, HBV-A and HDV-D genotypes are prevalent in Yakutia, in both monoinfected and HDV-coinfected patients. Bayesian analysis has shown that the high prevalence of HBV-A in Yakutia, which is not typical for Russia, initially emerged after the genotype was introduced from Eastern Europe in the fifteenth century (around 600 (95% HPD: 50–715) years ago). The acute hepatitis B epidemics in the 1990s in Yakutia were largely associated with this particular genotype, as indicated by temporal changes in HBV-A population dynamics. HBV-D had a longer history in Yakutia and demonstrated stable population dynamics, indicating ongoing viral circulation despite vaccination. No correlation between HBV and HDV genotypes was observed for coinfected patients in Yakutia (r = − 0.016069332). HDV-2b circulates in Russia in Yakutia only and resulted from a single wave of introduction from Central Asia 135 years ago (95% HPD: 60–350 years), while HDV-1 strains resulted from multiple introductions from Europe, the Middle East, Central Asia, and different parts of Russia starting 180 years ago (95% HPD: 150–210 years) and continuing to the present day. The population dynamics of HDV-1 and HDV-2 show no signs of decline despite 20 years of HBV vaccination. The Birth–Death Skyline analysis showed an increase in the viral population in recent years for both HDV genotypes, indicating ongoing HDV epidemics.

Conclusions

Taken together, these data call for strict control of HBV vaccination quality and coverage, and implementation of HBV and HDV screening programs in Yakutia.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12879-022-07444-w.

Presence of Liver Inflammation in Asian Patients With Chronic Hepatitis B With Normal ALT and Detectable HBV DNA in Absence of Liver Fibrosis

Liver biopsies are recommended to exclude significant liver inflammation in patients with chronic hepatitis B (CHB) with elevated HBV DNA but without other indications for antiviral treatment. We aimed to investigate the proportions and determinants of significant inflammation in Asian patients with CHB with detectable HBV DNA. We conducted a cross‐sectional study that retrospectively included 581 patients with CHB with detectable HBV DNA who had undergone liver biopsy. Liver inflammation and fibrosis were staged by Scheuer’s classification. Significant inflammation and significant fibrosis were defined as G ≥ 2 and S ≥ 2, respectively. There were 179 (30.8%) patients with alanine aminotransferase (ALT) < 1 × upper limit of normal (ULN), 205 (35.3%) patients with ALT 1‐2 × ULN, and 197 (33.9%) patients with ALT > 2 × ULN. A total of 397 (68.3%) patients had significant inflammation, and 340 (58.5%) patients had significant fibrosis. Significant inflammation was found in 85% of patients with significant fibrosis and in 44.8% of patients without significant fibrosis. Furthermore, 28.7% of patients with CHB with detectable HBV DNA and normal ALT in the absence of significant fibrosis had significant inflammation. Moderate HBV DNA (5‐7 log₁₀ IU/mL) was a risk factor for significant inflammation (odds ratio [OR] 6.929, 95% confidence interval [CI] 2.830‐16.966, P < 0.001) in patients with CHB with detectable HBV DNA, especially for patients with detectable HBV DNA and normal ALT in the absence of significant fibrosis (adjusted OR 13.161, 95% CI 1.026‐168.889, P = 0.048). Conclusion: A high proportion of CHB patients with detectable HBV DNA and normal ALT in the absence of significant fibrosis have significant liver inflammation. Liver biopsies are recommended to evaluate liver inflammation in such patients, especially for those with moderate HBV DNA.

Cirrhosis, Age, and Liver Stiffness-Based Models Predict Hepatocellular Carcinoma in Asian Patients with Chronic Hepatitis B

OBJECTIVES

Predicting hepatocellular carcinoma (HCC) in patients with chronic hepatitis B who received long-term therapy with potent nucleos(t)ide analogs is of utmost importance to refine the strategy for HCC surveillance.

METHODS

We conducted a multicenter retrospective cohort study to validate the CAGE-B and SAGE-B scores, HCC prediction models developed for Caucasian patients receiving entecavir (ETV) or tenofovir (TFV) for >5 years. Consecutive patients who started ETV or TFV at two hospitals in Korea from January 2009 to December 2015 were identified. The prediction scores were calculated, and model performance was assessed using receiver operating characteristics (ROC) curves.

RESULTS

Among 1557 patients included, 57 (3.7%) patients had HCC during a median follow-up of 93 (95% confidence interval, 73-119) months. In the entire cohort, CAGE-B predicted HCC with an area under the ROC curve of 0.78 (95% CI, 0.72-0.84). Models that have "liver cirrhosis" in the calculation, such as AASL (0.79 (0.72-0.85)), CU-HCC (0.77 (0.72-0.82)), and GAG-HCC (0.79 (0.74-0.85)), showed accuracy similar to that of CAGE-B (p > 0.05); however, models without "liver cirrhosis", including SAGE-B (0.71 (0.65-0.78)), showed a lower predictive ability than CAGE-B. CAGE-B performed well in subgroups of patients treated without treatment modification (0.81 (0.73-0.88)) and of male sex (0.79 (0.71-0.86)).

CONCLUSIONS

This study validated the clinical usefulness of the CAGE-B score in a large number of Asian patients treated with long-term ETV or TFV. The results could provide the basis for the reappraisal of HCC surveillance strategies and encourage future prospective validation studies with liver stiffness measurements.

CRISPR as a Diagnostic Tool

Clustered regularly interspaced short palindromic repeats (CRISPR)-Cas system has recently gained growing attention as a diagnostic tool due to its capability of specific gene targeting. It consists of Cas enzymes and a guide RNA (gRNA) that can cleave the target DNA or RNA based on the sequence of the gRNA, making it an attractive genetic engineering technique. In addition to the target-specific binding and cleavage, the trans-cleavage activity was reported for some Cas proteins, including Cas12a and Cas13a, which is to cleave the surrounding single-stranded DNA or RNA upon the target binding of Cas-gRNA complex. All these activities of the CRISPR-Cas system are based on its target-specific binding, making it applied to develop diagnostic methods by detecting the disease-related gene as well as microRNAs and the genetic variations such as single nucleotide polymorphism and DNA methylation. Moreover, it can be applied to detect the non-nucleic acids target such as proteins. In this review, we cover the various CRISPR-based diagnostic methods by focusing on the activity of the CRISPR-Cas system and the form of the target. The CRISPR-based diagnostic methods without target amplification are also introduced briefly.

Baseline serum hepatitis B core antibody level predicts HBeAg seroconversion in patients with HBeAg-positive chronic hepatitis B after antiviral treatment

Antibody to hepatitis B core antigen (anti-HBc) is one of the most classical serological markers of HBV infection. This study aimed to investigate the association of serum anti-HBc and HBeAg seroconversion in patients with HBeAg-positive chronic hepatitis B (CHB) after antiviral treatment. Two hundred and seventeen HBeAg-positive CHB patients treated with entecavir (ETV) or tenofovir disoproxil fumarate (TDF) for 48 weeks were retrospectively enrolled. Serological response (SR) is defined as HBeAg seroconversion at 48 weeks of antiviral treatment. Serum anti-HBc level was measured using the Abbott ARCHITECT assay. After 48 weeks of antiviral treatment, twenty-two (10.1 %) patients achieved SR. Baseline level of serum anti-HBc in the SR patients (11.8 S/CO) was significantly higher than patients with non-SR (9.6 S/CO, P < 0.001). The median anti-HBc level was significantly declined after 48 weeks of antiviral therapy (9.9 vs. 8.9 S/CO, P < 0.001). Multivariate logistic regression analysis showed baseline of serum anti-HBc was an independent predictor of SR (odds ratio [OR]: 1.462, 95 % confidence interval [CI] 1.170-1.825, P = 0.001). The area under receiver operating characteristic curve (AUROC) of baseline anti-HBc level for predicting SR was 0.781 with the cut-off of 11.1 S/CO, with a sensitivity of 77.27 % and a specificity of 72.82 %. Our findings highlighted that baseline serum anti-HBc level is a promising indictor for predicting HBeAg seroconversion in HBeAg-positive CHB patients after antiviral treatment.

rt269I Type of Hepatitis B Virus (HBV) Polymerase versus rt269L Is More Prone to Mutations within HBV Genome in Chronic Patients Infected with Genotype C2: Evidence from Analysis of Full HBV Genotype C2 Genome

Recently, it has been reported that the rt269I type of hepatitis B virus (HBV) polymerase (Pol) versus the rt269L type is more significantly related to lower viral replication and HBeAg negative infections in chronic hepatitis B (CHB) patients of genotype C2. In this study, we compared mutation rates within HBV genomes between rt269L and rt269I using a total of 234 HBV genotype C2 full genome sequences randomly selected from the HBV database (115 of rt269L and 119 of rt269I type). When we applied the Benjamini and Hochberg procedure for multiple comparisons, two parameters, dN and d, at the amino acids level in the Pol region were significantly higher in the rt269I type than in the rt269L type. Although it could not reach statistical significance from the Benjamini and Hochberg procedure, nonsynonymous (NS) mutations in the major hydrophilic region (MHR) or “a” determinant in the surface antigens (HBsAg ORF) related to host immune escape or vaccine escape are more frequently generated in rt269I strains than in rt269L. We also found that there are a total of 19 signature single nucleotide polymorphisms (SNPs), of which 2 and 17 nonsynonymous mutation types were specific to rt269L and rt269I, respectively: Of these, most are HBeAg negative infections (preC-W28*, X-V5M and V131I), lowered HBV DNA or virion production (C-I97F/L, rtM204I/V) or preexisting nucleot(s)ide analog resistance (NAr) (rtN139K/H, rtM204I/V and rtI224V) or disease severity (preC-W28*, C-I97F/L, C-Q182K/*, preS2-F141L, S-L213I/S, V/L5M, T36P/S/A, V131I, rtN139K/H, rtM204I/V and rtI224V). In conclusion, our data showed that rt269I types versus rt269L types are more prone to overall genome mutations, particularly in the Pol region and in the MHR or “a” determinant in genotype C2 infections and are more prevalent in signature NS mutations related to lowered HBV DNA replication, HBsAg and HBeAg secretion and potential NAr variants and hepatocellular carcinoma (HCC), possibly via type I interferon (IFN-I)-mediated enhanced inflammation. Our data suggest that rt269L types could contribute to liver disease progression via the generation of immune escape or enhanced persistent infection in chronic patients of genotype C2.

Distribution of hepatitis B virus genotypes in the general population of Myanmar via nationwide study

Background

Hepatitis B virus (HBV) infections are a severe health concern worldwide. HBV is a DNA virus with a rapid rate of mutation. Based on heterogeneity of the nucleotide sequence, the HBV strains are divided into nine genotypes, each with a characteristic geographical distribution. Identifying and tracking alterations of HBV genotypes is important in epidemiological and transmission studies, and contributes to predicting the risk for development of severe liver disease and response to antiviral treatment. The present study was undertaken to detect HBV genotypes and sub-genotypes in the general population of different states and regions in Myanmar.

Methods

In 2015, a total of 5547 adults of the general population, residing in seven states, seven regions and the Nay Pyi Taw Union Territory, were screened for Hepatitis B Surface antigen (HBsAg) by the immunochromatographic test (ICT). Of the 353 HBsAg positive samples, the HBVDNA was identified using polymerase chain reactions (PCR) targeting the DNA sequences encoding the Pre-S region. A total of 153 PCR positive samples were subsequently subjected to genotyping by partial genome sequencing in both directions. The resulting sequences were then edited, aligned, and compared with reference sequences using the National Centre for Biotechnology Information (NCBI) web-based genotyping tool.

Results

Three HBV genotypes (HBV genotype B, genotype C and genotype D) were detected in Myanmar, of which genotype HBV genotype C (66.7%) was the most prevalent, followed by HBV genotype D (32%) and HBV genotype B (1.3%). Sub-genotyping revealed a total of 7 variants within the B, C and D genotypes: 2 (B4 and B5) in HBV genotype B, 3 (C1, C5 and C7) in HBV genotype C, and 2 (D3 and D6) in HBV genotype D.

Conclusion

HBV genotype C, sub-genotype C1 was predominantly distributed in all states and regions of Myanmar. This study is the first report on the nationwide distribution of HBV genotypes and sub-genotypes in Myanmar. We believe our findings will enable huge support for the hepatitis disease surveillance program, since HBV infection is one of the National Priority Diseases in Myanmar.

Hepatitis B Virus Genotypes in the Kingdom of Bahrain: Prevalence, Gender Distribution and Impact on Hepatic Biomarkers

Background: Approximately 400 million people are infected with Hepatitis B virus (HBV) around the world, which makes it one of the world’s major infectious diseases. The prevalence of HBV genotypes and predictive factors for risk are poorly known in the Kingdom of Bahrain. Objectives: The aim of the present study was to investigate the prevalence of HBV genotypes, its correlation with demographic factor sand impacts on hepatic biomarkers. Materials and Methods: Venous blood samples were collected from 82 HBV positive patients (48 males, 34 females). The extraction of HBV DNA, PCR amplification, and genotyping were done to classify different genotypes (A, A/D, B, B/D, C, D, D/E, E). HBV genotypes association with gender, nationality, mode of transmission, and liver cirrhosis complication was determined by descriptive statistic and univariate analysis of variance (ANOVA). For liver function test, unpaired t-test and ANOVA were performed. Results: The predominant genotype among patients under study was genotype D (61%), followed by genotype A (10%), and lowest frequency was found for undetermined genotype (1%). In general, there was no significant association between the different genotypes and some demographical factors, serological investigations, and liver function test. The prevalence of HBV genotypes was higher in male patients as compared to female patients and higher in non-Bahraini than in Bahraini. Patients with the dominant genotype D showed higher than the normal maximum range for alanine aminotransferase (ALT) (mean = 45.89) and Gamma-glutamyl transferase (GGT) (mean = 63.36). Conclusions: The most common HBV genotype in Bahrain was genotype D, followed by genotype A. Further studies involving the sources of transmission and impact of hepatic biomarker in Bahrain are required to enhance the control measures of HBV infections.

Origin and dissemination of hepatitis B virus genotype C in East Asia revealed by phylodynamic analysis and historical correlates

Hepatitis B virus disease progression in East Asia is most frequently associated with genotype C (HBV/C). The increasing availability of HBV/C genetic sequences and detailed annotations provides an opportunity to investigate the epidemiological factors underlying its evolutionary history. In this study, the Bayesian phylogeography framework was used to investigate the origins and patterns in spatial dissemination of HBV/C by analyzing East Asian sequences obtained from 1992 to 2010. The most recent common ancestor of HBV/C was traced back to the early 1900s in China, where it eventually diverged into two major lineages during the 1930s-1960s that gave rise to distinct epidemic waves spreading exponentially to other East Asian countries and the USA. Demographic inference of viral effective population size over time indicated similar dynamics for both lineages, characterized by exponential growth since the early 1980s, followed by a significant bottleneck in 2003 and another increase after 2004. Although additional factors cannot be ruled out, we provide evidence to suggest this bottleneck was the result of limited human movement from/to China during the SARS outbreak in 2003. This is the first extensive evolutionary study of HBV/C in East Asia as well as the first to assess more realistic spatial ecological influences between co-circulating infectious diseases.

Genotypes and Hot Spot Mutations of Hepatitis B Virus in Northwest Chinese Population and Its Correlation with Diseases Progression

Hepatitis B virus (HBV) infection is a critical incentive for chronic hepatitis B (CHB), liver cirrhosis (LC), and hepatocellular carcinoma (HCC). Different genotypes and genome mutations of HBV have been found to be related to the progression of these liver diseases. However, their clinical significance is still under debate. The objective of this study was to determine the association of HBV genotypes and hot spot mutations in the reverse transcriptase (RT) and basal core promoter-precore (BCP-PreC) region with HBV-infected diseases in a northwest Chinese population. HBV genotyping and DNA sequencing were performed in samples of 980 patients. Appropriate statistical methods were adopted to assess HBV genetic features and its clinical association. It was found that the prevalent HBV genotype in northwestern Chinese patients was HBV/C (61.33%), followed by HBV/B (36.63%). In RT region, in addition to the reported nucleoside analogue- (NA-) resistance missense mutations, new silent mutations at rt169 and rt180 were found to raise the risk of HCC in patients with HBV/C. And the heterozygous mutation status of rt169/rt180 was associated with the increased risk of both HCC and NA resistance (OR > 1, P < 0.01) regardless of HBV genotypes. In BCP-PreC region, multiple mutations and combinations, especially at nt 1762/1764 and nt 1896/1899, were characterized to be the causes of spurious HBeAg negativity and liver function injury, as well as the risk factors for HCC progression (P < 0.01). Additionally, a novel mutation at nt1799G>C was likely found to increase the risk of HCC in patients with HBV/B. These findings revealed an association between HBV genotypes and HBV genetic mutations in RT and BCP-PreC region and progression of hepatitis B. It would be helpful for risk evaluation and diagnostic improvement based on these genetic features.

Genotype Matters in Patients with Acute-on-chronic Liver Failure Due to Reactivation of Chronic Hepatitis B

Background

Acute-on-chronic liver failure (ACLF) can be caused by reactivation of chronic hepatitis B virus (HBV) infection (HBV-ACLF). It’s unclear whether HBV genotypes affect the clinical and therapeutical outcomes of patients with HBV-ACLF. This study was to investigate the short-term antiviral response and overall survival in HBV-ACLF patients treated by tenofovir or entecavir.

Methods

Seventy-three consecutive patients with HBV-ACLF were stratified into genotype B group (n = 33) and C group (n = 40). They were prospectively followed-up.

Results

At 2 weeks, the genotype B group had significantly lower HBV-DNA load (P = 0.005), greater HBV-DNA decline (P = 0.026), higher proportion of patients with HBV-DNA < 500 IU/ml (P = 0.007), improved Child-Turcotte-Pugh (CTP; P = 0.032) and model for end-stage liver disease (MELD; P = 0.039) scores compared to the genotype C group. At three months, survivors in both groups had undetectable HBV-DNA loads, comparable CTP (P = 0.850) and MELD (P = 0.861) scores; the genotype C group had markedly lower overall survival rate than the B group (P = 0.013). The genotype (hazard ratio [HR]: 2.138; 95% confidence interval [CI]: 1.034–4.143; P = 0.041), MELD score (HR:1.664, 95%CI: 1.077–2.571; P = 0.022) and HBV-DNA decline (HR: 0.225, 95% CI: 0.067–0.758; P = 0.016) at 2 weeks were significantly associated with mortality at 3 months. No severe adverse event was noted.

Conclusions

Genotype B was associated with better short-term antiviral response and clinical outcome compared to genotype C in patients with HBV-ACLF.

A novel index using routine clinical parameters for predicting significant liver inflammation in chronic hepatitis B

Identifying the degree of liver inflammation is critical for therapeutic judgement of patients with chronic hepatitis B (CHB). However, we lack indexes which can accurately predict significant liver inflammation in patients with CHB. This study aimed to develop a simple predictive index for liver inflammation in CHB using routine clinical parameters. A total of 519 patients with CHB who underwent liver biopsy were enrolled and randomly divided into training (n = 346) and validation cohorts (n = 173). Based on routine clinical parameters, gamma-glutamyl transpeptidase (GGT; P = 0.031) and platelets (PLT; P < 0.001) were identified as independent predictors of significant inflammation by multivariable analysis in the training cohort. Accordingly, the GGT to PLT ratio (GPR) was developed to amplify the opposing effects for predicting liver inflammation. In the training cohort, the AUCs of GPR in predicting significant inflammation were 0.791 (95% CI: 0.742-0.839), 0.783 (95% CI: 0.717-0.849) and 0.791 (95% CI: 0.716-0.867) in the entire patients with CHB, HBeAg-positive CHB patients and HBeAg-negative CHB patients, respectively. The diagnostic performance of GPR for significant inflammation was significantly superior to that of alanine aminotransferase (ALT), aspartate transaminase (AST) and GGT in all patients with CHB and HBeAg-positive CHB patients, but was comparable with ALT, AST and GGT in HBeAg-negative CHB patients. In the validation cohort, the diagnostic performance of GPR in assessing significant liver inflammation was also superior to other indexes in all patients with CHB and HBeAg-positive CHB patients, but was comparable with GGT in HBeAg-negative CHB patients. Thus, GPR can be a novel and simple index for predicting significant liver inflammation in CHB, especially for HBeAg-positive CHB.

How viral genetic variants and genotypes influence disease and treatment outcome of chronic hepatitis B. Time for an individualised approach?

Chronic hepatitis B virus (HBV) infection remains a global problem. Several HBV genotypes exist with different biology and geographical prevalence. Whilst the future aim of HBV treatment remains viral eradication, current treatment strategies aim to suppress the virus and prevent the progression of liver disease. Current strategies also involve identification of patients for treatment, namely those at risk of progressive liver disease. Identification of HBV genotype, HBV mutants and other predictive factors allow for tailoured treatments, and risk-surveillance pathways, such as hepatocellular cancer screening. In the future, these factors may enable stratification not only of treatment decisions, but also of patients at risk of higher relapse rates when current therapies are discontinued. Newer technologies, such as next-generation sequencing, to assess drug-resistant or immune escape variants and quasi-species heterogeneity in patients, may allow for more information-based treatment decisions between the clinician and the patient. This article serves to discuss how HBV genotypes and genetic variants impact not only upon the disease course and outcomes, but also current treatment strategies. Adopting a personalised genotypic approach may play a role in future strategies to combat the disease. Herein, we discuss new technologies that may allow more informed decision-making for response guided therapy in the battle against HBV.

A novel predictive model using routinely clinical parameters to predict liver fibrosis in patients with chronic hepatitis B

Objectives

Noninvasive models have been established for the assessment of liver fibrosis in patients with chronic hepatitis B(CHB). However, the predictive performance of these established models remains inconclusive. We aimed to develop a novel predictive model for liver fibrosis in CHB based on routinely clinical parameters.

Results

Platelets(PLT), the standard deviation of red blood cell distribution width(RDW-SD), alkaline phosphatase(ALP) and globulin were independent predictors of significant fibrosis by multivariable analysis. Based on these parameters, a new predictive model namely APRG(ALP/PLT/RDW-SD/globulin) was proposed. The areas under the receiver-operating characteristic curves(AUROCs) of APRG index in predicting significant fibrosis(≥F2), advanced fibrosis(≥F3) and liver cirrhosis(≥F4) were 0.757(95%CI 0.699 to 0.816), 0.763(95%CI 0.711 to 0.816) and 0.781(95%CI 0.728 to 0.835), respectively. The AUROCs of the APRG were significantly higher than that of aspartate transaminase(AST) to PLT ratio index(APRI), RDW to PLT ratio(RPR) and AST to alanine aminotransferase ratio(AAR) to predict significant fibrosis, advanced fibrosis and cirrhosis. The AUROCs of the APRG were also significantly higher than fibrosis-4 score (FIB-4) (0.723, 95%CI 0.663 to 0.783) for cirrhosis(P=0.034) and better than gamma-glutamyl transpeptidase(GGT) to PLT ratio(GPR) (0.657, 95%CI 0.590 to 0.724) for significant fibrosis(P=0.001).

Materials and Methods

308 CHB patients who underwent liver biopsy were enrolled. The diagnostic values of the APRG for liver fibrosis with other noninvasive models were compared.

Conclusions

The APRG has a better diagnostic value than conventionally predictive models to assess liver fibrosis in CHB patients. The application of APRG may reduce the need for liver biopsy in CHB patients in clinical practice.

A noninvasive model to predict liver histology in HBeAg-positive chronic hepatitis B with alanine aminotransferase ≤ 2upper limit of normal

BACKGROUND AND AIM

Liver biopsy remains the gold standard to evaluate liver histology. However, it has several limitations. This study aims to construct a noninvasive model to predict liver histology for commencing antiviral therapy in HBeAg-positive chronic hepatitis B (CHB) with aminotransferase (ALT) ≤ 2 upper limit of normal (ULN).

METHODS

Two hundred and ninety-eight patients with HBeAg-positive CHB, ALT ≤ 2ULN and HBV-DNA ≥20 000 IU/ml were enrolled and randomly divided into a training group and a validation group. A noninvasive model was constructed in the training group to predict significant liver histological change [necroinflammatory activity grade (G) ≥ 2 or fibrosis stage (S) ≥ 2] and then validated in the validation group.

RESULTS

Aspartate aminotransferase, HBsAg, platelet, and albumin were identified as independent predictors. A model was constructed by them. It had an area under the receiver operating characteristic curve of 0.875 in the training group, 0.858 in the validation group and 0.868 in the entire cohort. Using a cut-off point of -0.96, it showed 93% sensitivity, 90% negative predictive value (NPV) in the training group and 95% sensitivity, 94% NPV in the validation group. Using a cut-off point of 0.96, it showed 95% specificity, 91% positive predictive value (PPV) in the training group and 89% specificity, 80% PPV in the validation group.

CONCLUSIONS

This study constructed a noninvasive model to predict liver histology in HBeAg-positive CHB with ALT ≤ 2ULN, which might reduce the clinical need for liver biopsy.

Hepatitis B and Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is one of the leading causes of cancer death worldwide, and its incidence has been increasing in the last decade largely in parallel to the incidence and duration of exposure to hepatitis B and C. The widespread implementation of hepatitis B vaccine, hepatitis B antivirals, and the introduction of direct antiviral therapies for hepatitis C virus may have a substantial impact in reducing the incidence of HCC. This report reviews the risk factors and underlying mechanisms associated with the development of HCC in hepatitis B, along with advances in the diagnosis, imaging, and management of HCC.

Molecular Evolution and Phylodynamics of Acute Hepatitis B Virus in Japan

Hepatitis B virus (HBV) is prevalent worldwide and causes liver diseases, including acute and chronic hepatitis. Ten HBV genotypes (A–J) with distinct geographic distributions have been reported. Cases of acute HBV infection with genotype A have increased in Japan nationwide since the 1990s, mainly through sexual transmission. To investigate the molecular evolution and phylodynamics of HBV genotypes, we collected acute HBV isolates acquired in Japan from 1992–2002. Full genomes were obtained for comprehensive phylogenetic and phylodynamic analysis, with other Japanese HBV sequences from GenBank that were isolated during 1991–2010. HBV genotypes were classified using the maximum-likelihood and Bayesian methods. The GMRF Bayesian Skyride was used to estimate the evolution and population dynamics of HBV. Four HBV genotypes (A, B, C, and H) were identified, of which C was the major genotype. The phylodynamic results indicated an exponential growth between the 1960s and early 1990s; this was followed by a population bottleneck after 1995, possibly linked with successful implementation of a nationwide vaccination program. However, HBV/A increased from 1990 to 2003–2004, and then started to decrease. The prevalence of genotype A has increased over the past 10 years. Phylodynamic inference clearly demonstrates a steady population growth compatible with an ongoing subepidemic; this might be due to the loss of immunity to HBV in adolescents and people being born before the vaccination program. This is the first phylodynamic study of HBV infection in Japan and will facilitate understanding the molecular epidemiology and long-term evolutionary dynamics of this virus in Japan.

Precore/core region mutations of hepatitis B virus related to clinical severity

Despite the availability of an effective vaccine, hepatitis B virus (HBV) infection remains a major health problem, with more than 350 million chronically infected people worldwide and over 1 million annual deaths due to cirrhosis and liver cancer. HBV mutations are primarily generated due both to a lack of proofreading capacity by HBV polymerase and to host immune pressure, which is a very important factor for predicting disease progression and therapeutic outcomes. Several types of HBV precore/core (preC/C) mutations have been described to date. The host immune response against T cells drives mutation in the preC/C region. Specifically, preC/C mutations in the MHC class II restricted region are more common than in other regions and are significantly related to hepatocellular carcinoma. Certain mutations, including preC G1896A, are also significantly related to HBeAg-negative chronic infection. This review article mainly focuses on the HBV preC/C mutations that are related to disease severity and on the HBeAg serostatus of chronically infected patients.

Clinical findings in a multi-ethnic adult hepatitis B virus patient population in Denmark with emphasis on genotypic characteristics

OBJECTIVE

Most knowledge about chronic hepatitis B virus (HBV) infection is based upon studies in high-endemic areas with one or two predominant genotype(s). The aim of the study was to describe clinical characteristics of a heterogeneous genotypic HBV patient population in a low-endemic European country.

METHODS

Data from HBV patients currently followed in a Danish university hospital and affiliated regional clinics were reviewed in accordance to genotype status.

RESULTS

Of 540 HBV patients, 462 (86%) were of non-Danish ethnicity originating from 43 different countries. HBV genotype was known in 37% of the patients: A (11%), B (25%), C (25%), D (37%) and E (2%). Logistic regression analysis of pre-treatment data among genotype A-D patients receiving nucleos(t)ide analogue (NA) therapy revealed a decreased HBeAg rate by age (OR = 0.93; CI: 0.89-0.97; p < 0.01) and an increased rate in genotype C patients (OR = 20.5; CI: 3.3-129; p < 0.01). Among untreated patients HBeAg rate was also significantly decreased by age (OR = 0.90 (0.85:0.95; p < 0.0001), whereas the rate was increased in both genotype B and C patients (OR = 7.5; CI: 1.8-30.5; p < 0.01 and OR = 12.2; CI: 3.2-46.6; p < 0.001, respectively). No significant variation was found in HBV DNA level in any of the two groups when adjusting for age, gender, genotype and HBeAg. Increased liver pathology prevalence was, irrespectively of treatment status, associated to age and male gender, but not to any genotype.

CONCLUSION

In this study population, genotype B and C was found associated with higher HBeAg rate but not with increased liver pathology.

A model to predict antiviral treatment in HBeAg negative chronic hepatitis B with alanine aminotransferase≤2 upper limit of normal

BACKGROUND & AIMS

Liver histological assessment is essential for predicting antiviral therapy in HBeAg negative chronic hepatitis B (CHB) patients with serum alanine aminotransferase (ALT)≤2 upper limit of normal (ULN). The aim was to establish a model to predict antiviral treatment for those patients without liver biopsy.

METHODS

Three hundred and one consecutive treatment naive HBeAg negative CHB patients with HBV DNA≥2000 IU/ml and ALT≤2 ULN were retrospectively enrolled, among which 158 patients were for the training set and 143 for validation set. A multivariate logistic regression model was constructed in the training set and validated in the validation set.

RESULTS

Our model identified four independent factors for the timing of treatment: Age (OR 1.050, 95%CI 1.004-1.098), Ln(aspartate aminotransferase) (OR 17.425, 95%CI 5.394-56.292), Log10 [HBV DNA] (OR 0.704, 95%CI 0.514-0.963) and platelet (OR 0.980, 95%CI 0.970-0.990). It showed 94% sensitivity, 88% negative predictive value (NPV) in the training set and 93% sensitivity, 85% NPV in the validation set using the low cut-off point of 5.16. Meanwhile, it showed 92% specificity, 88% positive predictive value (PPV) in the training set and 94% specificity, 92% PPV in the validation set using the high cut-off point of 7.26. It could predict treatment for 179 of 301(59%) patients without biopsy.

CONCLUSIONS

We established a model to predict antiviral therapy in HBeAg negative CHB patients with ALT≤2 ULN. Antiviral treatment should be initiated if the model value>7.26 and not if its value≤5.16. Liver biopsy is needed only when its value between the two points.

Distribution and diversity of hepatitis B virus genotypes in Yunnan, China

Hepatitis B virus (HBV) is one of the most prevalent pathogens in the world, and infection with this virus is a serious threat for public health. Yunnan is considered as an important endemic center for blood-borne viruses such as human immunodeficiency virus and hepatitis C virus, in China. However, the distribution and diversity of HBV subgenotypes remain unclear in Yunnan province. In the current study, HBV positive samples were collected from different prefectures of Yunnan province and their molecular epidemiological characters were determined. Phylogenetic analysis on the pre-S/S gene (865 bps) showed the prevalence of four HBV genotypes, including genotype B (24 cases, 33.3%), genotype C (45 cases, 62.5%), genotype I (two cases, 2.78%) and C/D recombinants (one case, 1.39%). The most prevalent genotypes B and C could be sub classified into subgenotype B2 and C1, C2, C5, and C7, respectively. Clusters of subgenotype B2 and C2 consisted of strains from China and other East Asian countries, while subgenotype C1, C5, and C7 and genotype I formed a cluster together with strains from Southeast Asia. Using Bayesian inference from phylogenetic, HBV genotypes B and C were estimated to have originated in 1860s and 1910s with an evolutionary rate of 3.26 and 8.01 × 10(-4) substitutions/site/year, respectively. These findings indicate that the distribution of HBV genotypes in Yunnan was influenced by strains from the rest of China and the neighboring countries.

The genotype C could play a key role in hepatitis B virus associated nephritis among the northwest Chinese children

BACKGROUND

Hepatitis B virus-associated glomerulonephritis (HBV-GN) is a kind of immune complex-induced glomerulonephritis. The present study was designed to determine whether Hepatitis B virus (HBV) genotype is associated with glomerulonephritis in north-west Chinese children.

METHODS

A total of 296 HBV-infected patients were enrolled in this study. The serum of patients was subjected to DNA extraction and the HBV genotypes were determined by PCR.

RESULTS

The results showed that genotype C (49%) was predominant within the subjects, compared to HBV/B (38.5%), B/C recombinant (7.4%) and none B/C (5.1%). The serum tests showed that the changes of Complement 3 (C3) and alanine amino transferase (ALT) levels in the genotype C patients were significantly greater than those in the genotype B patients. The frequency of genotype C in HBV-GN patients was higher than that in non HBV-GN patients (χ2 value=30.239, P<0.001). But, it was not associated with renal dysfunction. Furthermore, The genotype C was associated with high HBV-DNA load (82.9% vs 17.1%, P<0.001), which is seen more frequently in the HBV-GN children (86.3% vs 13.3%, P=0.004).

CONCLUSIONS

The genotype C may play a role in HBV-GN children, via favoring HBV replication.

RDW to platelet ratio: a novel noninvasive index for predicting hepatic fibrosis and cirrhosis in chronic hepatitis B

Objective

To develop a simple predictive model for significant fibrosis and cirrhosis in chronic hepatitis B (CHB) using the routine hematological parameters of a complete blood count.

Methods

A total of 458 eligible CHB patients who had undergone a liver biopsy were randomly divided into two cohorts: an estimation group (n = 310) and a validation group (n = 148). Liver histology was assessed according to the Metavir scoring scheme. All common demographics, hematological parameters, HBeAg status, HBV DNA, and liver biochemistry were analyzed.

Results

Based on routinely available clinical parameters (age, sex, HBeAg status, HBV DNA, common hematological parameters of a complete blood cell count), a model for predicting significant fibrosis (Metavir score ≥2) in the estimation group was derived using platelets and red cell distribution width (RDW), and another model for predicting cirrhosis (Metavir score = 4) was derived using platelets, RDW and hemoglobin. A novel index, the RDW to platelet ratio (RPR), was developed to amplify the opposing effects of liver fibrosis on the RDW and platelets. The AUCs of the RPR for predicting significant fibrosis and cirrhosis were 0.825 and 0.884, respectively, which is superior to the AAR, FIB-4 and APRI in the estimation group. Compared with the two derived models, the RPR has a comparable predictive power for significant fibrosis and cirrhosis. Using optimized cutoffs (0.10 and 0.16), the RPR accurately predicted 63.1% of cases with significant fibrosis and 73.7% of cases with cirrhosis and accurately excluded 85.5% of the cases with mild fibrosis and 93.0% of the cases with no cirrhosis.

Conclusion

The RPR, a routinely available, inexpensive and easily calculated index, can predict significant fibrosis and cirrhosis in CHB patients with relatively high accuracy. The application of this index may reduce the need for liver biopsy in CHB patients.

Molecular epidemiology of hepatitis B in the Indigenous people of northern Australia

BACKGROUND AND AIM

The hepatitis B surface antigen was first described in the blood of an Indigenous Australian man, yet little is known about its molecular epidemiology in this population, in which it is endemic. The study aimed to determine the clinical and molecular epidemiology of hepatitis B virus (HBV) in Indigenous people from northern Australia.

METHODS

Following ethics approval and informed consent, blood specimens and clinical details from Indigenous adults known to be infected with HBV and who were born and raised in Indigenous communities in northern Australia were obtained. HBV genotypes were determined in isolates with sufficient HBV DNA by polymerase chain reaction by sequencing of the polymerase/surface gene.

RESULTS

Between June 2010 and June 2012, 65 patients were recruited from six different regions of northern Australia. Thirty-two patients (49%) were hepatitis B e-antigen-positive, and 48% were hepatitis B e-antibody-positive. No patients were found to be coinfected with hepatitis C virus or human immunodeficiency virus. Of the 49 samples with sufficient viral load for genotyping, 100% were infected with genotype C4, previously only reported from two Indigenous Australians. All isolates had wild-type polymerase gene sequences despite 14 currently or previously receiving antiviral treatment. The canonical sG145R vaccine-escape variant was detected in the surface antigen of virus from two patients.

CONCLUSIONS

The exclusive HBV genotype in this ancient population is genotype C4. Whole genome sequencing and clinical follow-up of this cohort are in progress, with the aim of exploring the clinical significance of these findings.

Hepatitis B virus genotype C encoding resistance mutations that emerge during adefovir dipivoxil therapy: in vitro replication phenotype

INTRODUCTION

Hepatitis B virus (HBV) can be classified into ten genotypes (A-J), with genotypes B and C being the most common in Asia. Recent data suggest that the HBV genotype can influence disease progression, and genotype C has been associated with more aggressive liver disease than that of other genotypes. Although there is a preventative vaccine, chronic infection remains a public health problem with oral nucleos(t)ide analog therapy being the most common treatment. The HBV genome is composed of four partially overlapping reading frames, meaning that substitutions in the HBV polymerase selected during NA therapy may also alter the overlapping HBV surface antigen (HBsAg). We have recently shown that for HBV genotype D, the rtA181T/sW172stop substitution conferring resistance to adefovir dipivoxil (ADV) alters secretion of HBsAg and exerts a dominant-negative effect on wild-type virion secretion. However, the effect of this and other ADV-resistance-associated mutations on HBV replication and HBsAg secretion for the HBV genotype C, the genotype with the most severe clinical prognosis, is unknown.

METHODS/RESULTS

We constructed 1.2-mer infectious cDNA clones of HBV genotype C encoding mutations associated with ADV resistance and established an in vitro replication assay in Huh7 cells. Decreased levels of HBV DNA and HBsAg were detected for all ADV variants relative to the 1.2-mer wild-type polymerase control plasmid. Importantly, less HBsAg was detected in the cells transfected with the rtA181T resistance mutants, and the overlapping sW172stop mutation ablated secretion of HBsAg into cell culture supernatants.

CONCLUSIONS

The identification of secretion-defective HBV in the setting of ADV therapy for HBV genotype C, and to a lesser extent HBV genotype B, has major implications for the diagnosis and treatment of HBV in the Asia-Pacific region, as it is likely that quantitative HBsAg and viral load testing of serum from patients infected with HBV encoding rtA181T and rtN236T substitutions may not accurately reflect the level of replication within hepatocytes.

Analysis of precore/core covariances associated with viral kinetics and genotypes in hepatitis B e antigen-positive chronic hepatitis B patients

Hepatitis B virus (HBV) is one of the most common DNA viruses that can cause aggressive hepatitis, cirrhosis and hepatocellular carcinoma. Although many people are persistently infected with HBV, the kinetics in serum levels of viral loads and the host immune responses vary from person to person. HBV precore/core open reading frame (ORF) encoding proteins, hepatitis B e antigen (HBeAg) and core antigen (HBcAg), are two indicators of active viral replication. The aim of this study was to discover a variety of amino acid covariances in responses to viral kinetics, seroconversion and genotypes during the course of HBV infection. A one year follow-up study was conducted with a total number of 1,694 clones from 23 HBeAg-positive chronic hepatitis B patients. Serum alanine aminotransferase, HBV DNA and HBeAg levels were measured monthly as criteria for clustering patients into several different subgroups. Monthly derived multiple precore/core ORFs were directly sequenced and translated into amino acid sequences. For each subgroup, time-dependent covariances were identified from their time-varying sequences over the entire follow-up period. The fluctuating, wavering, HBeAg-nonseroconversion and genotype C subgroups showed greater degrees of covariances than the stationary, declining, HBeAg-seroconversion and genotype B. Referring to literature, mutation hotspots within our identified covariances were associated with the infection process. Remarkably, hotspots were predominant in genotype C. Moreover, covariances were also identified at early stage (spanning from baseline to a peak of serum HBV DNA) in order to determine the intersections with aforementioned time-dependent covariances. Preserved covariances, namely representative covariances, of each subgroup are visually presented using a tree-based structure. Our results suggested that identified covariances were strongly associated with viral kinetics, seroconversion and genotypes. Moreover, representative covariances may benefit clinicians to prescribe a suitable treatment for patients even if they have no obvious symptoms at the early stage of HBV infection.

The influence of HLA alleles and HBV subgenotyes on the outcomes of HBV infections in Northeast China

Hepatitis B virus (HBV) infection has a wide variety of clinical outcomes, it could be spontaneouly recovered and also could develop fulminant liver failure or cirrhosis with hepatocellular carcinoma. Human leukocyte antigen (HLA) polymorphism and HBV (sub)genotypes have been speculated to associate with the outcome of HBV infection because the data obtained from various populations who bear different HLA alleles have shown a HLA polymorphism associated outcome of HBV infection. However, as the most important viral and host genetic factors, the impact of HBV (sub)genotypes in combination with HLA polymorphism on the clinical outcomes of HBV infections remains unclear. To demonstrate the association of HLA allele polymorphism in combination with HBV subgenotypes with the outcome of HBV infection in Northeastern Han Chinese population, a total of 230 HBV-infected individuals (Infection group) were compared to 210 random selected controls (Control group) who are negative for HBV infection for their HLA alleles frequency as well as the associations with the virus infection, clearance and persistence in combination with HBV subgenotypes. Of the 230 HBV-infected subjects, 54 were acute self-limited hepatitis (ASH) with HBV subgenotype C2 (ASH-C2), 144 were chronic hepatitis (CH) with HBV subgenotype C2 and B2 (CH-C2 and CH-B2), and 32 were spontaneously recovered (SR) without subgenotype results. When two groups are compared, the results suggest that B*48, B*51 and DRB1*12 carrier may have a high risk for HBV infection, but B*51 is likely association with spontaneous recovery and DRB1*07, 12 may be implied in viral persistence. HLA-B*15, DRB1*11 and 14 associated with viral clearance in the cases of HBV-C2 infection; HLA-B*54 carriers in chronic group are more sensitive to with the infection of HBV subgenotype B2; HLA-B*07 and DRB1*13 may protect subjects from HBV infection. The data presented a link between HLA polymorphism and HBV pathogenesis and suggested potential therapeutic targets for hepatitis B.

Subgenotype and genetic variability in the precore/core regions of hepatitis B virus in Korean patients with chronic liver disease

OBJECTIVE

The aim of this study was to determine the prevalence of hepatitis B virus (HBV) subgenotypes, the spectrum of mutations in the precore/core region through phylogenetic analysis, and the relevance of viral characteristics in disease progression in Korean patients.

METHODS

133 patients with chronic HBV infection were enrolled. The precore and core region of HBV was amplified and sequenced. Phylogenetic analysis was performed for subgenotyping and the changes of nucleotides and amino acid were compared in liver disease stages.

RESULTS

HBV/C2 subgenotype was predominant in chronic HBV carriers (98.5%), followed by HBV/A2 (0.75%) and HBV/C7 (0.75%). The mutations of the precore region were not different between liver disease stages. However, amino acid changes in the cytotoxic T lymphocyte epitope (p < 0.020), CD4+ T cell epitope (p < 0.027), or B cell epitope (p < 0.029) were significantly higher in liver cirrhosis patients than in chronic hepatitis patients, but not in hepatocellular carcinoma patients.

CONCLUSION

HBV/C2 is the most prevalent subgenotype in Korea, and HBV/C7 subgenotype found in the Philippines was first identified in the Korean population. Mutations in immune epitopes within the core gene were significantly associated with disease progression.

JGH Foundation emerging leadership lecture. Significance of hepatitis B virus genotypes and mutations in the development of hepatocellular carcinoma in Asia

Advances in molecular biology technology in the last two decades have allowed detailed study of the viral mutations and genomic heterogeneity of hepatitis B virus (HBV). The first mutant discovered was precore stop codon mutation. It was reported in HBeAg-negative patients and initially thought to associate with fulminant hepatitis. Subsequent studies have suggested that it is merely one of the mechanisms of losing HBeAg by the virus. Another mutation that can downregulate the production of HBeAg is the basal core promoter mutation, which is located in the X gene upstream of the precore region. Based on the configuration of codon 15 and the stability of the epsilon of the precore region, these two mutants will be differentially selected during the course of HBeAg seroconversion. The most common HBV genotypes in South-East Asia are genotype B and C HBV. The higher hepatocellular carcinoma (HCC) risk of genotype C HBV has been confirmed by longitudinal studies in Hong Kong and Taiwan. One possible carcinogenic mechanism is its association with basal core promoter mutation, which has also been found to be a risk factor of HCC. Within genotype C HBV, subgenotype Cs is predominant in South-East Asia and subgenotype Ce is predominant in East Asia. Subgenotype Ce HBV has been found to have the highest risk of HCC as compared with subgenotype Cs or genotype B HBV. The understanding of the carcinogenic mechanisms of these HBV strains may shed light into future therapeutics in the prevention and treatment of HBV-related HCC.

The clinical implications of hepatitis B virus genotype: Recent advances

Outcomes of chronic hepatitis B virus (HBV) infection are heterogeneous. Estimates of annual incidence of cirrhosis and hepatocellular carcinoma (HCC) are 2-10% and 1-3%, respectively. Several viral factors, including HBV genotype, viral load and specific viral mutations, have been associated with disease progression. Among these, HBV genotype is not only predictive of clinical outcomes but has also been associated with response to interferon treatment. Currently, at least 10 HBV genotypes and several subtypes have been identified; they have distinct geographic distribution. Acute infection with genotypes A and D results in higher rates of chronicity than genotypes B and C. Compared to genotype A and B cases, patients with genotypes C and D have lower rates of spontaneous hepatitis B e antigen (HBeAg) seroconversion; when this occurs, it tends to be delayed. HBV genotype C has a higher frequency of basal core promoter (BCP) A1762T/G1764A mutation, pre-S deletion and is associated with higher viral load than genotype B. Similarly, genotype D has a higher prevalence of BCP A1762T/G1764A mutation than genotype A. These observations suggest important pathogenic differences between HBV genotypes. These may contribute to more severe liver disease, including cirrhosis and HCC with genotypes C and D HBV infection. In addition, genotype A and B patients have better responses to interferon-based therapy than genotypes C and D, but there are few consistent differences for direct HBV antivirals. In conclusion, genotyping of chronic HBV infections can help practicing physicians identify those at risk of disease progression and determine optimal anti-viral therapy.

Hepatitis B virus (HBV) subgenotypes C2 and B2 differ in lamivudine- and adefovir-resistance-associated mutational patterns in HBV-infected Chinese patients

We aimed to study the prevalence and clinical implications of hepatitis B virus (HBV) subgenotypes in Chinese patients. A total of 4,300 patients, mainly from northern China, were enrolled, including 182 patients with acute hepatitis B and 4,118 patients with chronic HBV infection who had been exposed to nucleoside or nucleotide analogs. HBV genotypes/subgenotypes were determined by direct sequencing of the HBV S/Pol region. The prevalence rates were 0.40% for HBV/B1, 14.30% for HBV/B2, 0.25% for HBV/B3, 0.35% for HBV/B4, 1.05% for HBV/C1, 81.72% for HBV/C2, 0.93% for HBV/C3, 0.16% for HBV/C4, and 0.84% for HBV/D. In chronic HBV infection, patients with HBV/B2 were younger and had lower ΗBeAg positive rates than patients with HBV/C2. The incidence of lamivudine-resistant mutations was significantly higher in HBV/C2 compared to HBV/B2 (27.9% versus 19.8%; P<0.01), and the significant difference was observed only for rtM204I and not rtM204V. In addition, compensatory mutations were more frequently detected in HBV/C2. The incidence of adefovir-resistant mutations was similar between the two subsets, but HBV/C2 inclined to show rtA181V (3.6% for C2 versus 0.9% for B2; P<0.01), while HBV/B2 inclined to show rtN236T (4.5% for versus 2.5% for C2; P<0.01). The ratios of HBV/B2 to HBV/C2 infection were 1.7 (110/65), 5.7 (2,653/463), 7.5 (520/69), 8.0 (48/6), and 15.3 (183/12) for acute hepatitis B, chronic hepatitis B, liver cirrhosis, acute-on-chronic liver failure, and hepatocellular carcinoma, respectively. In conclusion, HBV/C2 and HBV/B2, two prevalent subgenotypes, differ in lamivudine- and adefovir-resistance-associated mutational patterns. HBV/C2-infected patients are more likely to have disease progression than HBV/B2-infected ones.