Therapeutic implications of hepatitis B virus genotypes

Role of Immunological Cells in Hepatocellular Carcinoma Disease and Associated Pathways

Hepatocellular carcinoma (HCC) remains one of the predominant causes of cancer-related mortality across the globe. It is attributed to obesity, excessive alcohol consumption, smoking, and infection by the hepatitis virus. Early diagnosis of HCC is essential, and local treatments such as surgical excision and percutaneous ablation are effective. Palliative systemic therapy, primarily with the tyrosine kinase inhibitor Sorafenib, is used in advanced cases. However, the prognosis for advanced HCC remains poor. This Review additionally describes the pathophysiological mechanisms of HCC, which include aberrant molecular signaling, genomic instability, persistent inflammation, and the paradoxical position of the immune system in promoting and suppressing HCC. The paper concludes by discussing the growing body of research on the relationship between mitochondria and HCC, suggesting that mitochondrial dysfunction may contribute to the progression of HCC. This Review focuses on immunological interactions between different mechanisms of HCC progression, including obesity, viral infection, and alcohol consumption.

Hepatitis b infection: progress in identifying patients most likely to respond to peginterferon alfa

Introduction: Despite the disadvantage of side effects, pegylated interferon alpha (Peg-IFN α) remains an indispensable agent for chronic hepatitis B (CHB) due to its immunomodulatory effect. The selection of a patient most likely to have a favorable response becomes an essential issue for Peg-IFN α therapy.Areas covered: Recent progress in the prediction of the treatment response to Peg-IFN α.Expert opinion: Before Peg-IFN α therapy, baseline host and viral factors, including female sex, younger age, a high alanine aminotransferase level, HBV genotype A or B, and low viral load, predict a favorable response. In addition, on-treatment viral kinetics of hepatitis B surface antigen (HBsAg), e antigen (HBeAg) and HBV DNA help clinicians determine whether to continue or discontinue Peg-IFN α therapy. The novel HBV markers hepatitis B core-related antigen and HBV RNA have recently been investigated as useful predictors. The limited efficacy of Peg-IFN α monotherapy facilitated the development of new strategies of 'add-on' or 'switch to' Peg-IFN α in patients receiving long-term nucleot(s)ide analog treatment, which may lead to an increase in HBeAg and HBsAg loss. In summary, tailored Peg-IFN α therapeutic strategies based on predictors extended the landscape for CHB treatment.

Comparing CLIF-C ACLF, CLIF-C ACLFlactate, and CLIF-C ACLF-D Prognostic Scores in Acute-on-Chronic Liver Failure Patients by a Single-Center ICU Experience

Patients with liver cirrhosis have a higher risk of developing acute-on-chronic liver failure (ACLF). Poor prognosis with a high rate of short-term mortality leads to limited opportunities for further liver transplantation. Thus, precise prognostic evaluation of patients with ACLF is necessary before transplant surgery. In this study, a total of one hundred and thirty-five patients with ACLF admitted to the hepato-gastroenterologic intensive care unit (ICU) for intensive monitoring and treatment at Chang-Gung Memorial Hospital (CGMH, Linkou, Taiwan) were screened from November 2012 to April 2015 and tracked until April 2017. Three new prognostic scores of ACLF, including CLIF-C ACLF (Chronic Liver Failure Consortium Acute-on-chronic Liver Failure score), CLIF-C ACLF-D (CLIF-C ACLF Development score), and CLLF-C ACLF_lactate (lactate-adjusted CLIF-C ACLF score) were compared. The primary outcome considered was overall mortality. Mortality predictions at 28, 90, 180, and 365 days were also calculated. By area under the receiver operating characteristic curve (AUROC) analysis, the CLIF-C ACLF and CLIF-C ACLF-D scores were superior to CLIF-C ACLF_lactate scores in predicting 28-day mortality. The CLIF-C ACLF-D score had the highest AUROC in predicting overall mortality as well as at 90, 180, and 365 days. In conclusion, our study demonstrates that CLIF-C ACLF and CLIF-C ACLF-D scores are significant predictors of outcome in critical patients with liver cirrhosis and ACLF. The CLIF-C ACLF-D score may have a superior predictive power for the prediction of 3-month, 6-month, and one-year mortality.

GEHEP 010 study: Prevalence and distribution of hepatitis B virus genotypes in Spain (2000-2016)

OBJECTIVE

To study the prevalence and distribution of HBV genotypes in Spain for the period 2000-2016.

METHODS

Retrospective study recruiting 2559 patients from 17 hospitals. Distribution of HBV genotypes, as well as sex, age, geographical origin, mode of transmission, HDV-, HIV- and/or HCV-coinfection, and treatment were recorded.

RESULTS

1924 chronically HBV native Spanish patients have been recruited. Median age was 54 years (IQR: 41-62), 69.6% male, 6.3% HIV-coinfected, 3.1% were HCV-coinfected, 1.7% HDV-co/superinfected. Genotype distribution was: 55.9% D, 33.5% A, 5.6% F, 0.8% G, and 1.9% other genotypes (E, B, H and C). HBV genotype A was closely associated with male sex, sexual transmission, and HIV-coinfection. In contrast, HBV genotype D was associated with female sex and vertical transmission. Different patterns of genotype distribution and diversity were found between different geographical regions. In addition, HBV epidemiological patterns are evolving in Spain, mainly because of immigration. Finally, similar overall rates of treatment success across all HBV genotypes were found.

CONCLUSIONS

We present here the most recent data on molecular epidemiology of HBV in Spain (GEHEP010 Study). This study confirms that the HBV genotype distribution in Spain varies based on age, sex, origin, HIV-coinfection, geographical regions and epidemiological groups.

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.

Negative HBcAg in immunohistochemistry assay of liver biopsy is a predictive factor for the treatment of patients with nucleos(t)ide analogue therapy

The hepatitis B core antigen (HBcAg) is an important target for antiviral response in chronic hepatitis B (CHB) patients. However, the correlation between HBcAg in the hepatocyte nucleus and nucleos(t)ide analogue (NA) therapeutic response is unclear. We sought to evaluate the role of HBcAg by analysing liver biopsies for viral response in NA-naïve hepatitis B e antigen (HBeAg) positive (+) CHB patients via immunohistochemistry (IHC). A total of 48 HBcAg-negative (-) patients and 48 HBcAg (+) patients with matching baseline characteristics were retrospectively analysed for up to 288 weeks. Virological response (VR) rates of patients in the HBcAg (-) group were significantly higher at week 48 and 96 than the HBcAg (+) group (77.1% versus 45.8% at week 48, respectively, P = 0.002 and 95.3% versus 83.3% at week 96, respectively, P = 0.045). The serological negative conversion rate of HBeAg was significantly higher in the HBcAg (-) than in the HBcAg (+) group from week 96 to 288 (35.4 % versus 14.6% at week 96, respectively, P = 0.018; 60.4% versus 14.6%, respectively, P < 0.001 at week 144; 72.9% versus 35.4%, respectively, P < 0.001 at week 288). The cumulative frequencies of VR and lack of HBeAg were higher in the HBcAg (-) group (both P < 0.05). Binary logistic regression analysis showed that HBcAg (-) was the predictor for the lack of HBeAg (OR 4.482, 95% CI: 1.58-12.68). In summary, the absence of HBcAg in the hepatocyte nucleus could be an independent predictor for HBeAg seroconversion rates during NA-naïve treatment in HBeAg (+) CHB patients.

Identification of hepatitis B virus A1762T/G1764A double mutant strain in patients in Southern Brazil

Infection by hepatitis B virus (HBV) is a worldwide public health problem. Chronic HBV infection with high viral replication may lead to cirrhosis and/or hepatocellular carcinoma. Mutant HBV strains, such as the HBV A1762T/G1764A double mutant, have been associated with poor prognosis and higher risk of the patient for developing cirrhosis and/or hepatocellular carcinoma. This study analyzed the presence of the HBV A1762T/G1764A double mutant in patients with chronic HBV and its association with clinical parameters such as viral load, aminotransferases, and HBV antigens. A total of 49 patients with chronic hepatitis B were included in the study, and the HBV A1762T/G1764A double mutant strain was detected in four samples (8.16%) by polymerase chain reaction followed by restriction fragment length analysis (PCR-RFLP). The viral load was not significantly different between patients with or without the double mutant strain (p=0.43). On the other hand, carriers of the HBV A1762T/G1764A double mutant had higher levels of ALT (p=0.0028), while AST levels did not differ between groups (p=0.051). In this study, 75% of the samples with the HBV A1762T/G1764A double mutation were HBeAg negative and anti-HBe positive, reflecting seroconversion even though they still displayed high viral loads. Our study has shown that the HBV A1762T/G1764A double mutant strain circulates in Brazilian patients, and is associated with elevated levels of ALT and HBeAg seroconversion.

Hepatitis B virus infection in undocumented immigrants and refugees in Southern Italy: demographic, virological, and clinical features

Background

The data on hepatitis b virus (HBV) infection in immigrants population are scanty. The porpoise of this study was to define the demographic, virological, and clinical characteristics of subjects infected with HBV chronic infection in a cohort of immigrants living in Naples, Italy.

Methods

A screening for HBV infection was offered to 1,331 immigrants, of whom 1,212 (91%) (831 undocumented immigrants and 381 refugees) accepted and were screened for hepatitis B surface antigen (HBsAg) and anti-hepatitis B core antibody (HBc). Those found to be HBsAg positive were further investigated at third-level infectious disease units.

Results

Of the 1,212 immigrants screened, 116 (9.6%) were HBsAg positive, 490 (40.4%) were HBsAg negative/anti-HBc positive, and 606 (50%) were seronegative for both. Moreover, 21 (1.7%) were anti-human immunodeficiency virus positive and 45 (3.7%) were anti-hepatitis C virus positive. The logistic regression analysis showed that male sex (OR: 1.79; 95%CI: 1.28–2.51), Sub-Saharan African origin (OR: 6.18; 95%CI: 3.37–11.36), low level of schooling (OR: 0.96; 95%CI: 0.94–0.99), and minor parenteral risks for acquiring HBV infection (acupuncture, tattoo, piercing, or tribal practices, OR: 1.54; 95%CI: 1.1–2.16) were independently associated with ongoing or past HBV infection. Of the 116 HBsAg-positive immigrants, 90 (77.6%) completed their diagnostic itinerary at a third-level infectious disease unit: 29 (32.2%) were asymptomatic non-viremic HBsAg carriers, 43 (47.8%) were asymptomatic viremic carriers, 14 (15.6%) had chronic hepatitis, and four (4.4%) had liver cirrhosis, with superimposed hepatocellular carcinoma in two.

Conclusions

The data illustrate the demographic, clinical and virological characteristics of HBV infection in immigrants in Italy and indicate the need for Italian healthcare authorities to enhance their support for providing screening, HBV vaccination, treatment, and educational programs for this populations.

Electronic supplementary material

The online version of this article (doi:10.1186/s40249-016-0228-4) contains supplementary material, which is available to authorized users.

Virus-induced hepatocellular carcinoma with special emphasis on HBV

Hepatocellular carcinoma (HCC) is a common malignant tumor with high lethality, and the hepatitis B virus (HBV) is a chief cause. HBV can accelerate HCC via multiple mechanisms. First, HBV induces immune reactions that lead to repeated hepatic inflammation, fibrosis and a deficient immune microenvironment. Subsequently, HBV can modify host genes near the insertion point through DNA integration to cause host cell genome instability and to generate carcinogenic fusion proteins. Additionally, HBV expresses diverse active proteins, especially HBx and HBs, which have a range of transactivation functions such as regulation of apoptosis, interference with intracellular signaling pathways, and alteration of epigenetics. Currently, primary prevention measures for HBV-induced HCC focus on vaccination and antiviral treatment. Here, we report the epidemiology, the molecular mechanism and the progress in therapeutic strategies for controlling HBV-induced HCC.

Treatment strategies according to genotype for chronic hepatitis B in children

This review article was requested by editor-in-chief of this journal as 'pediatric CHB treatment' for the upcoming special issue. The main objective of chronic hepatitis B (CHB) treatment is diminishing the risk of complications related to chronic liver disease. In Asia, there are already some reports about hepatocellular carcinoma (HCC) in hepatitis B virus (HBV) infected children. The key points of treatment in children with CHB infections are selection of which patients to treat and conformation of the optimal therapy time that would reduce viral resistance. The choice of therapy is determined by the district (Western/Eastern), HBV genotype, medical accessibility, and economic state of the country. Newly developed nucleos(t)ide analogues (NAs) are potent in children with CHB. However, to improve therapeutic efficacy, physicians are recommended to follow treatment guidelines and determine the specific genotype in the CHB patient. In this article, the treatment of pediatric CHB is reviewed according to differences in genotype.

Predictive Factors in the Incidence of Cirrhosis in Chronic Hepatitis B Virus Infections

BACKGROUND

Hepatitis B virus (HBV) is among the leading causes of liver cirrhosis worldwide. Predictors of cirrhosis in Iranian chronic hepatitis B (CHB) patients are yet to be clearly identified.

OBJECTIVES

Evaluating the predictive factors of liver cirrhosis in CHB.

PATIENTS AND METHODS

A longitudinal study was conducted during 1995 - 2014 on all CHB patients who were referred to Tehran hepatitis center, Tehran, Iran. The patients were assessed during periodic visits through medical history and laboratory data. Logistic regression analyses were used to determine predictors of cirrhosis.

RESULTS

Two hundred thirty-seven CHB patients were followed for an average duration of 10.6 years, and 41 of these patients developed cirrhosis. The incidence rate of cirrhosis was 2.82/100 person-years. Univariate analyses determined 9 out of 17 factors as significant predictors of outcome in CHB patients. Age of ≥ 45 years, positive hepatitis D virus (HDV), negative HBeAg, platelet count of < 150 (× 10(9))/L, and HBV DNA level of ≥ 2,000 IU/mL were identified as significant independent predictors of liver cirrhosis in multiple logistic analyses.

CONCLUSIONS

Five predictive factors that are simple and easy to measure may be used as parameters for the prediction of liver cirrhosis in CHB patients.

Hepatitis B virus genotypes and variants

At least 10 hepatitis B virus (HBV) genotypes (A to J) with distinct geographic distributions and several HBV mutants, including precore/core promoter mutations and pre-S/S deletion mutations, have been recognized to be not only predictive of liver disease progression but also associated with response to antiviral therapy. HBV genotype-specific pathogenesis may contribute to heterogeneous clinical outcomes in chronic hepatitis B patients across the world. For example, patients with HBV genotypes C and D infection have a lower rate of spontaneous HBeAg seroconversion. In addition, HBV genotypes C and D have a higher frequency of core promoter and pre-S mutations than genotypes A and B. Genotypes C and D also carry a higher lifetime risk of cirrhosis and HCC development than genotypes A and B. Core promoter and pre-S mutations also correlate with an increased risk of hepatocellular carcinoma (HCC). Therapeutically, genotypes A and B patients have a better response to interferon-based therapy than genotypes C and D patients, but the response to nucleos(t)ide analogs is comparable across different HBV genotypes. In conclusion, HBV genotypes and variants may serve as viral genetic markers to predict disease progression as well as help practicing physicians optimize individualized antiviral therapy in clinical practice.

Point-of-care screening, prevalence, and risk factors for hepatitis B infection among 3,728 mainly undocumented migrants from non-EU countries in northern Italy

BACKGROUND

Screening migrants from areas where hepatitis B virus (HBV) infection is endemic is important to implement preventive measures in Europe. The aim of our study was to assess (1) the feasibility of point-of-care screening in a primary care clinic and (2) hepatitis B surface antigen (HBsAg) prevalence, associated risk factors, and its clinical and epidemiological implications in undocumented migrants in Brescia, northern Italy.

METHODS

A longitudinal prospective study was conducted from January 2006 to April 2010 to assess HBsAg reactivity and associated risk factors among consenting undocumented migrants who accessed the Service of International Medicine of Brescia's Local Health Authority. Genotyping assay was also performed in HBV DNA-positive patients.

RESULTS

Screening was accepted by 3,728/4,078 (91.4%) subjects consecutively observed during the study period, 224 (6%) of whom were found to be HBsAg-positive. HBsAg reactivity was independently associated with the prevalence of HBsAg carriers in the geographical area of provenance (p < 0.001). On the contrary, current or past sexual risk behaviors (despite being common in our sample) were not associated with HBV infection. Half of the HBsAg patients (111/224) had either hepatitis B e-antigen (HBeAg)-positive or -negative chronic HBV infection with a possible indication for treatment. HBV genotypes were identified in 45 of 167 HBV-infected patients as follows: genotype D, 27 subjects; genotype A, 8; genotype B, 5; and genotype C, 5. The geographical distribution of genotypes reflected the geographic provenance.

CONCLUSIONS

Our results suggest that point-of-care screening is feasible in undocumented migrants and should be targeted according to provenance. Case detection of HBV infection among migrants could potentially reduce HBV incidence in migrants' contacts and in the general population by prompting vaccination of susceptible individuals and care of eligible infected patients.

Micro-evolution of the hepatitis B virus genome in hepatitis B e-antigen-positive carriers: comparison of genotypes B and C at various immune stages

BACKGROUND AND AIM

Patients with hepatitis B virus (HBV) genotype B infection experience hepatitis B e-antigen (HBeAg) seroconversion at an earlier stage than do patients with genotype C infection. Therefore, this study investigated whether the differential phenotypes are related to HBV genomic evolution.

METHODS

Thirty-three HBeAg-positive patients with a mean follow-up of 3.1 years were enrolled: 16 at the immune tolerance stage (group I) and 17 at the immune clearance stage (group II). The evolution rates of paired viral genomes at enrollment and at the final follow-up in the full-length genome (μf), nonoverlapping regions (synonymous [μs] and nonsynonymous [μa]), and overlapping regions (μ) were calculated. The evolution rates were then compared according to serum alanine aminotransferase (ALT) levels and HBV genotype.

RESULTS

The overall μf evolution rate was lower in group I than in group II (1.4 × 10(-5)  ± 3.3 × 10(-5) vs 1.2 × 10(-3)  ± 1.2 × 10(-3) nucleotide substitution/site/year, P < 0.001). We observed similar results for the μs, μa, and μ evolution rates. All evolution parameters were comparable between genotypes B and C. We determined a positive correlation between μa/y and the area under the average ALT time curve in genotype B (R(2)  = 0.6935, P < 0.0001), but not in genotype C (R(2)  = 0.1606, P = 0.124).

CONCLUSION

The evolution rate of the HBV genome is higher at the immune clearance stage than at the immune tolerance stage. Host immune selection might play a role in triggering evolution of genotype B.

Molecular epidemiology of hepatitis B virus genotypes circulating in acute hepatitis B patients in the Campania region

Fifty-three HBV-DNA-positive patients with symptomatic acute hepatitis B were enrolled from 1999 to 2010 to evaluate molecular and phylogenetic changes in HBV in southern Italy. HBV polymerase region was evaluated by direct sequencing in plasma samples obtained at first observation. Different data sets were aligned and a phylogenetic tree was inferred using PhyML program. Statistical robustness was confirmed with a bootstrap analysis. A Bayesian Markov chain Monte Carlo method and a Bayesian skyline plot were used to estimate the evolution of our samples. The dN/dS rate (ω) was estimated by the maximum likelihood approach to investigate the presence of codons under positive selection. The MacClade program was used to test viral gene out/in flow only among HBV-D3 subgenotype patients with different risk factors. Of the 53 patients, 83% were born in Italy and 17% were foreigners. HBV genotype D was prevalent (64.1%), followed by genotype A (26.4%), E (3.8%), and F (5.7%). The prevalent subgenotype was D3 (70.6%). The Bayesian tree of the 24 D3 subgenotypes showed two main clades both dated 1994; 40% of viral gene flow observed was from intravenous drugs users and heterosexual patients. Phylogenetic analysis of HBV isolates showed that HBV-D3 remains the prevalent genotype, but also subgenotype A2 has become frequent in southern Italy. This may be of clinical relevance in years to come, since patients with HBV-genotype-A chronic infection less frequently than those with genotype D develop HBeAg-negative chronic hepatitis and respond more frequently to alfa-interferon treatment.

Significance of viral status on occurrence of hepatitis B-related hepatocellular carcinoma

Hepatitis B virus (HBV) infection remains a challenging global health problem, with more than 350 million people chronically infected and at risk of developing hepatocellular carcinoma (HCC). Interactions that occur among host, environmental, and viral factors determine the natural course and predict the prognosis of patients with chronic HBV infection. In the past decades, several important viral factors of predictive of HCC have been identified, such as high hepatitis B surface antigen level, seropositivity of hepatitis B e antigen, high viral load, viral genotype, and specific viral sequence mutations. Identification of certain viral risk factors for HCC development and stratification of patient risk are very important to perform future surveillance programs. In this article, we thus reviewed the risk of viral factors involved in hepatocarcinogenesis.

Individual prediction model for lamivudine treatment response in hepatitis B virus e antigen-positive chronic hepatitis B patients

BACKGROUND AND AIMS

Although prolonged lamivudine (LAM) therapy is associated with the emergence of LAM-resistant mutations, it is still a commonly used therapy in many Asian countries because of its established long-term safety and low cost. The aim of our study was to assess the predictors of long-term LAM treatment response and to establish an individual prediction model (IPM) for hepatitis B virus e antigen (HBeAg) seroconversion in HBeAg-positive chronic hepatitis B (CHB) patients.

METHODS

This was a multicenter analysis of 838 patients treated with LAM between January 1999 and August 2004. Of these, 748 patients were followed up for at least 24 months.

RESULTS

The median age was 43.0 years (range, 19-79 years) and the mean duration of LAM monotherapy was 34.2 ± 0.7 months. In the multivariate analysis, age (odds ratio [OR] = 0.974, P < 0.001), baseline alanine aminotransferase level (OR = 1.001, P = 0.014), and baseline hepatitis B virus DNA level (OR = 0.749, P < 0.001) were independent factors for HBeAg seroconversion. Based on the predictors, an IPM was established. Patients were classified into high (> 50%), intermediate (30-50%), or low (≤ 30%) response groups based on their probability of HBeAg seroconversion according to the IPM. The cumulative HBeAg seroconversion rate at 6 years for the high, intermediate, and low response groups was 66.0%, 48.5%, and 21.8%, respectively (P < 0.001).

CONCLUSIONS

An IPM was developed based on predictors of HBeAg seroconversion in HBeAg-positive CHB patients on LAM monotherapy. This model will allow screening of LAM responders prior to the commencement of antiviral treatment.

Melting curve analysis for the screening of hepatitis B virus genotypes A, D and F in patients from a general hospital in southern Brazil

CONTEXT

Hepatitis B virus (HBV) can cause fulminant hepatitis, cirrhosis and hepatocellular carcinoma, and is one of the most common causes of acute and chronic liver failure. The genetic variants of HBV can be decisive for the evolution of these diseases as well as for the election of therapy.

OBJECTIVES

The aim of this study was to evaluate and standardize an in house methodology based on the analysis of the melting curve polymerase chain reaction (PCR) of real-time (qPCR) to screen for genotypes A, D and F of HBV in patients from a hospital in Rio Grande do Sul, Brazil.

METHODS

We evaluated 104 patients presumably with HBV chronic infection. Viral DNA was extracted from plasma and viral genotypes and different mutations were determined using PCR-based protocols.

RESULTS

A PCR-based methodology was standardized for the analysis of genotypes A, D and F of HBV. The technique was based in a nested PCR with the final step consisting of a multiplex real-time PCR, using the melting curve as a tool for the differentiation of fragments. A higher frequency of genotype D (44.4%), followed by genotype A (22.2%) and genotype F (3.7%) was observed.

CONCLUSION

The standardized assay, a nested PCR-multiplex qPCR using specific primers, provides a rapid and accurate method for the differentiation of HBV genotypes that are more frequent in Southern Brazil - A, D and F. This method can be applied in the clinical practice.

In vitro replication competence of a hepatitis B genotype D/A recombinant virus: dissimilar biological behaviour regarding its parental genotypes

Hepatitis B virus (HBV) DNA recombinants contribute to ~30% of the overall full-length sequences already deposited in GenBank. However, their biological behaviour has not been analysed so far. In this study, the in vitro replication kinetics of the first D/A recombinant from the American continent differed from its parental genotypes, exhibiting higher extracellular levels of HBV DNA and hepatitis B e antigen. Southern blots of intracellular core-associated HBV DNA were in agreement with such results. Because this recombinant was obtained from an Argentinian injecting drug user belonging to a vulnerable community, these results are of singular relevance for regional public health. Further in vivo studies are urgently needed to determine the pathogenicity of these replicative competent clones.

Chronic hepatitis B in children and adolescents: epidemiology and management

Hepatitis B virus (HBV) infection is a worldwide health problem, which can cause acute liver failure, acute hepatitis, chronic hepatitis, liver cirrhosis, and liver cancer. It is most prevalent in Asia, Africa, Southern Europe, and Latin America. Approximately 2 billion people in the world have been infected by HBV, with more than 350 million as chronic carriers. Implementation of the HBV vaccine led to a significant reduction in viral transmission in many areas of the world; however, it remains highly endemic in many developing countries. The main source of infection in childhood is via perinatal transmission or horizontal transmission during preschool years. The majority of children with chronic hepatitis B (CHB) infection are asymptomatic; however, they may develop progressive disease and are at increased risk of advanced liver disease or liver cancer before their third decade. All children with chronic HBV infection should be regularly monitored for disease progression. The goal of therapy for children with CHB is to arrest disease progression and reduce the risk of developing cirrhosis and cancer. The available medications have a low success rate because of immunotolerance in the child and the development of viral resistance to standard therapy. Therefore, case selection and determination of the best time to commence treatment are essential to increase treatment efficacy and reduce the risk of viral resistance.

Stochastic model for estimating the risk of transfusion-transmitted hepatitis B in Vietnam

BACKGROUND AND OBJECTIVE

Transfusion-transmitted hepatitis B virus (HBV) infection may originate from hepatitis B surface antigen (HBsAg) false-negative blood donors, HBsAg negative and anti-HBc positive blood donors and blood donors with both tests negative. HBV DNA may be present in all these cases and blood may be infectious. The aim of the study was to estimate the risk of transfusion-transmitted HBV in Vietnam using a stochastic Monte Carlo model.

METHODS

A cross-sectional study of HBV prevalence in 1200 potential blood donors in rural Vietnam is used as basis for the Monte Carlo model together with expert panel estimates of occult hepatitis B infection (OBI) prevalence in blood donors.

RESULTS

With 1 000 000 blood donors running in the model, the potential OBI ranged from 658 to 747 blood units per million at 5 percentile and from 1342 to 2507 blood units per million at 95 percentile resulting in the risk of post-transfusion hepatitis ranging from 66 to 250 blood units per million assuming that risk of post-transfusion from potential OBI is 10%. Using the manufacturer's HBsAg sensitivity, the mean rate of blood units per million donations having false-negative HBsAg results was 298 (5-95 percentile: 14-893). When the test sensitivity was set lower, false-negative tests was observed at a mean of 1087 per million (5-95 percentile: 762-3220). The fraction of potential OBI donors increased with the increasing age in both genders.

CONCLUSION

Current HBsAg screening in Vietnam is insufficient in eliminating the risk of transfusion-transmitted HBV infection. The major risk factors are HBsAg false-negative results and OBI. Increased test sensitivity and locally validated HBsAg assays are recommended.

Prevalence, clinical and virologic outcomes of hepatitis B virus co-infection in HIV-1 positive Kenyan women on antiretroviral therapy

Background

Sub-Saharan Africa carries a high burden of co-infection with HIV-1 and hepatitis B virus (HBV). In this region, individuals with HIV-1/HBV co-infection on antiretroviral therapy (ART) frequently receive lamivudine as the only agent active against HBV, raising concerns for development of HBV resistance to lamivudine. We aimed to determine the prevalence, clinical, and virologic outcomes of chronic HBV infection, including HBV resistance to lamivudine, in a cohort of HIV-1 seropositive Kenyan women on long-term ART.

Methods

In this prospective cohort study, HIV-1 seropositive women initiated three-drug ART regimens that included lamivudine as the single drug active against HBV. Archived samples were tested for HBsAg, with further testing to determine HBeAg seroprevalence, HBV DNA suppression, and lamivudine resistance. We estimated the prevalence of chronic HBV and examined associations between HBV co-infection and clinical and virologic outcomes with chi-square tests, logistic regression, Kaplan-Meier and Cox regression.

Results

In a cohort of 159 women followed for a median of 3.4 years (interquartile range 1.4–4.5), 11 (6.9%; 95% CI 3.1–10.7) had chronic HBV infection. Of these, 9 (82%) achieved undetectable plasma HBV DNA levels. One woman developed lamivudine resistance, for an incidence of 3 per 100 person-years. The HBV co-infected women were at greater risk for abnormal ALT elevations compared to HIV-1 mono-infected women (HR 2.37; 95% CI 1.1–5.3). There were no differences between HBV-infected and uninfected women in mortality, CD4 count, or HIV-1 RNA suppression.

Conclusion

The prevalence of chronic HBV in this cohort was similar to recent studies from other African populations. Given our long-term follow-up, lamivudine resistance was lower than expected for HIV-1/HBV co-infected patients. Improved screening for HBV and extended follow-up of HIV-1/HBV co-infected individuals are needed to better understand the impact of different ART regimens on clinical outcomes in this population.

Management of chronic hepatitis B: Canadian Association for the Study of the Liver consensus guidelines

Chronic hepatitis B (CHB) is a dynamic disease that is influenced by host and virological factors. The management of CHB has become more complex with the increasing use of long-term oral nucleos⁄tide analogue antiviral therapies and the availability of novel diagnostic assays. Furthermore, there is often a lack of robust data to guide optimal management such as the selection of therapy, duration of treatment, potential antiviral side effects and the treatment of special populations. In November 2011, the Canadian Liver Foundation and the Canadian Association for the Study of the Liver convened a consensus conference to review the literature and analyze published data, including other international expert guidelines on CHB management. The proceedings of the consensus conference are summarized and provide updated clinical practice guidelines to assist Canadian health care providers in the prevention, diagnosis, assessment and treatment of CHB.

Longitudinal change of HBsAg in HBeAg-negative patients with genotype B or C infection

Background & Aims

Quantitative HBsAg has been recognized to assist in the management of chronic hepatitis B virus (HBV) infection. However, its role in disease monitoring of HBeAg-negative patients remains unclear. We aimed to investigate the longitudinal HBsAg change in HBeAg-negative carriers with HBV genotype B or C infection.

Methods

This is a retrospective cohort study conducted in a university hospital. Treatment-naïve HBeAg-negative carriers followed for more than 3 years were recruited. Their hepatitis activities were categorized by longitudinal HBV-DNA levels into high viral-load (HVL: HBV-DNA >/ = 2000 IU/mL persistently), low viral-load (LVL: HBV-DNA <2000 IU/mL persistently) and fluctuated viral-load (FVL: HBV-DNA between HVL and LVL). The baseline and end-of-follow-up (EOF) HBsAg levels were quantified for analyses.

Results

We recruited 187 patients with a median follow-up of 8 years. LVL patients had a significantly lower HBsAg at baseline and EOF and a significantly greater annualized HBsAg decline compared with the FVL and HVL. The longitudinal HBsAg change was independent of genotype B or C. The lower baseline HBsAg level predicted the HBsAg decline and HBsAg loss, whereas the higher baseline HBV-DNA predicted the hepatitis flare. A baseline HBsAg <50 IU/mL predicted subsequent HBsAg loss with a sensitivity of 82% and specificity of 67%. The annualized HBsAg decline appeared non-linear, and accelerated as the HBsAg level lowered (0.054, 0.091, 0.126 log₁₀ IU/mL in patients with baseline HBsAg >1000, 100–999, <100 IU/mL, respectively, P for trend = .014).

Conclusions

In genotype B or C HBeAg-negative carriers, baseline HBsAg levels correlate with future disease activities and help to predict HBsAg decline or loss. Inactive carriers with lower baseline HBsAg levels have a greater and accelerating HBsAg decline over time, regardless of HBV genotypes.

TP53 R249S mutation, genetic variations in HBX and risk of hepatocellular carcinoma in The Gambia

In regions with high prevalence of chronic hepatitis B virus (HBV) infection and dietary aflatoxin B(1) (AFB(1)) exposure, hepatocellular carcinomas (HCCs) often contain TP53 mutation at codon 249 (R249S). Furthermore, a C-terminal truncated HBx protein expressed from hepatocyte integrated HBV is associated with HCC development. This study evaluates the association between R249S and HBX status in relation to HCC in West African population. HBX (complete or 3'-truncated) and HBS genes were assessed by PCR in cell-free DNA (CFDNA) from plasma of subjects recruited in a hospital-based case-control study (325 controls, 78 cirrhotic patients and 198 HCC cases) conducted in The Gambia. These samples had been previously analyzed for R249S and HBV serological status. Complete HBX sequence was frequently detected in CFDNA of HCC-R249S positive (77%, 43/56) compared with HCC-R249S-negative cases (44%, 22/50). Conversely, the proportion of 3'-truncated HBX gene was significantly higher in HCC-R249S negative than positive cases (34%, 17/50, compared with 12%, 7/56) (χ(2) = 12.12; P = 0.002; distribution of R249S negative and positive according to HBX status). Occult HBV infection (detected by PCR) was present in 24% of HCC previously considered as negative by HBV serology. Moreover, HBV mutation analysis revealed that double mutation at nucleotides 1762(T)/1764(A) was associated with diagnosis of cirrhosis or HCC {cirrhosis: odds ratio (OR): 9.50 [95% confidence interval (CI) 1.50-60.11]; HCC: OR: 11.29 [95% CI 2.07-61.47]}. These findings suggest that in HCC from The Gambia, complete HBX sequences are often associated with the presence of TP53 R249S mutation.

TP53 R249S mutation, genetic variations in HBX and risk of hepatocellular carcinoma in The Gambia

In regions with high prevalence of chronic hepatitis B virus (HBV) infection and dietary aflatoxin B(1) (AFB(1)) exposure, hepatocellular carcinomas (HCCs) often contain TP53 mutation at codon 249 (R249S). Furthermore, a C-terminal truncated HBx protein expressed from hepatocyte integrated HBV is associated with HCC development. This study evaluates the association between R249S and HBX status in relation to HCC in West African population. HBX (complete or 3'-truncated) and HBS genes were assessed by PCR in cell-free DNA (CFDNA) from plasma of subjects recruited in a hospital-based case-control study (325 controls, 78 cirrhotic patients and 198 HCC cases) conducted in The Gambia. These samples had been previously analyzed for R249S and HBV serological status. Complete HBX sequence was frequently detected in CFDNA of HCC-R249S positive (77%, 43/56) compared with HCC-R249S-negative cases (44%, 22/50). Conversely, the proportion of 3'-truncated HBX gene was significantly higher in HCC-R249S negative than positive cases (34%, 17/50, compared with 12%, 7/56) (χ(2) = 12.12; P = 0.002; distribution of R249S negative and positive according to HBX status). Occult HBV infection (detected by PCR) was present in 24% of HCC previously considered as negative by HBV serology. Moreover, HBV mutation analysis revealed that double mutation at nucleotides 1762(T)/1764(A) was associated with diagnosis of cirrhosis or HCC {cirrhosis: odds ratio (OR): 9.50 [95% confidence interval (CI) 1.50-60.11]; HCC: OR: 11.29 [95% CI 2.07-61.47]}. These findings suggest that in HCC from The Gambia, complete HBX sequences are often associated with the presence of TP53 R249S mutation.

Differential clinical and virologic impact of hepatitis B virus genotypes B and C on HIV-coinfected patients receiving lamivudine-containing highly active antiretroviral therapy

BACKGROUND

 The impact of hepatitis B virus (HBV) genotypes B and C on the clinical, immunologic, and virologic outcomes of human immunodeficiency virus (HIV)-infected patients with chronic HBV infection remains largely unknown.

METHODS

 Between January 1997 and December 2008, we enrolled 96 HIV-infected patients with HBV genotype B coinfection and 49 with genotype C coinfection; the patients were followed prospectively until December 2010. Clinical and immunologic outcomes in the context of HBV genotypes as well as the emergence of HBV DNA mutations conferring lamivudine resistance (rtM204I/V) were determined.

RESULTS

 The median duration of lamivudine-containing highly active antiretroviral therapy (HAART) was 2.80 years (interquartile range, 1.73-5.92 years). The 2 groups of HIV-infected patients were comparable in age, sex, baseline HIV profiles, and liver function profiles. Compared with HIV-infected patients with HBV genotype C coinfection, those with genotype B coinfection had a higher risk of hepatitis flares (43.8% vs 26.5%; P = .04), liver disease-related death (9.4% vs 0%; P = .03), hepatitis B e antigen (HBeAg) seroconversion (61.5% vs 25.0%, P = .03), and development of lamivudine resistance (31.3% vs 12.2%; P < .0001). No differences were observed between the 2 groups in terms of the development of hyperbilirubinemia, cirrhosis, or virologic and immunologic responses to HAART.

CONCLUSIONS

 Although therapeutic responses to long-term lamivudine-containing HAART were comparable between HIV-infected patients with HBV genotypes B and C coinfection, patients with genotype B coinfection were more likely to experience acute exacerbations of hepatitis, HBeAg seroconversion, lamivudine resistance, and liver disease-related death than those with genotype C coinfection.

Molecular epidemiology of hepatitis B virus

Although safe and effective vaccines for hepatitis B virus (HBV) have been available for nearly three decades, this virus kills at least 600,000 people annually worldwide and remains the leading global cause of chronic hepatitis, cirrhosis, and hepatocellular carcinoma. Because the HBV reverse transcriptase lacks a proofreading function, many HBV genotypes, subgenotypes, mutants, and recombinants exist. At least 10 HBV genotypes (HBV-A through J) with distinct geographic distributions have been identified; by definition, their complete genomic sequences diverge by more than 8%. HBV genotype is increasingly becoming recognized as an important factor in the progression and clinical outcome of HBV-induced disease. Infections by HBV-C or -D are significantly more likely to lead to cirrhosis and hepatocellular carcinoma than are infections by HBV-A or -B. Additionally, the hepatitis B e antigen seroconversion response to standard or pegylated interferon is more favorable in patients with HBV-A or -B than in those with HBV-C or -D. However, therapeutic responses to nucleos(t)ide analogues are generally comparable among HBV genotypes. In conclusion, genotyping of HBV is useful in identifying chronic hepatitis B patients who are at increased risk of disease progression, thereby enabling physicians to optimize antiviral therapy for these patients.

Prevalence of Genotype D and Precore/Core Promoter Mutations in Hepatitis B Virus-infected Population of North India

Hepatitis B virus (HBV) isolates (21) from Punjab (North India) were studied for genotype distribution and precore/core promoter mutations. Assays of alanine aminotransaminase (ALT) and HBeAg were performed in all isolates. Genotypes were determined in all the samples by restriction fragment length polymorphism and the precore/core promoter mutations were studied by amplification and by direct sequencing of precore/core promoter region. Sixty-two percent of the isolates had higher ALT levels and 57% of the isolates were HBeAg negative. It was observed that 90% of the isolates were HBV D genotype (subgenotype D1 and D2) and 10% of the isolates were HBV A genotype (subgenotype A1). Amplification and sequencing of the precore/core promoter region showed 1762(A-T) and 1764(G-A) mutations in 29% and 19% of the isolates, respectively. 1809(C/T) mutation was observed in 71% of the isolates under study. Novel precore and core promoter mutations like 1690(A), 1695(A/T/G), 1700(A/C), 1703(c), 1850(A) and 1915(A/G) were observed in HBV-infected population of the state of Punjab (North India). Deletion and insertional mutations were also observed in some patients. (J CLIN EXP HEPATOL 2011;1:73-76).

HBV DNA loss within 24 weeks predicts late viral breakthrough in chronic hepatitis B

BACKGROUND/AIMS

Sustained HBV DNA reduction is necessary for biochemical remission, histological improvement, and prevention of complications. We analyzed the time taken from HBV DNA loss to viral breakthrough after antiviral treatment in patients with chronic hepatitis B (CHB). The early fall of the HBV DNA level to undetectable levels assessed really whether it is related to late breakthrough.

METHODS

A total of 91 patients whose HBV DNA levels dropped below undetectable levels were chosen from lamivudine-treated 306 patients and were analyzed retrospectively. The patients were divided into 4 groups (A≤12, 12<B≤24, 24<C≤48, D>48 wk) according to the time taken for the HBV DNA to decrease below undetectable levels. HBV DNA level was determined every 3 months.

RESULTS

The mean time taken for loss of HBV DNA was 34±28 wk. The baseline ALT differed significantly among groups (A: 382±274, B: 340±30, C: 166±92, D: 54±100 IU/L) (p=0.007). Fifty nine of the 91 patients (64.8%) experienced viral breakthrough. The mean interval between HBV DNA loss and viral breakthrough was 65±40 wk and differed significantly between group A, B (82±43 wk) and group C, D (56±28 wk) (p=0.015). In multivariate analysis, only HBV DNA loss within 24 wk, was found to be independently associated with late viral breakthrough (p=0.035). Undetectable HBV DNA after 24 wk was associated with high odd ratio of 3.24 (95% CI, 1.09-9.67).

CONCLUSIONS

HBV DNA loss within 24 wk after antiviral treatment could predict the late breakthrough.

Recent advances in the research of hepatitis B virus-related hepatocellular carcinoma: epidemiologic and molecular biological aspects

Hepatocellular carcinoma (HCC) is one of the commonest cancers worldwide, and more than half of HCC patients are attributable to persistent hepatitis B virus (HBV) infections. The best and cheapest way to prevent HBV-related HCC is the implementation of universal hepatitis B vaccination program, by which the incidence rates of childhood HCC have been reduced in several countries, including Taiwan. However, there are still hundreds of millions of HBV carriers in the world that remain a global health challenge. In the past decade, several hepatitis B viral factors such as serum HBV DNA level, genotype, and naturally occurring mutants have already been identified to influence liver disease progression and HCC development in HBV carriers. Several easy-to-use scoring systems based on clinical and viral characteristics are developed to predict HCC risk in HBV carriers and may facilitate the communication between practicing physicians and patients in clinical practice. In addition, the role of nonviral factors in HBV-related HCC has also been increasingly recognized. On the basis of these emerging data, it is recommended that HBV carriers should be screened and monitored to identify those who have a higher risk of liver disease progression and require antiviral treatments. Regarding the molecular carcinogenesis of HCC development, despite some progress in the research of cell biology of HCC in the past decade, aberrant pathways involved in maintaining HCC phenotypes have not been completely elucidated yet. In the future, through comprehensive and integrated approaches to analyze the genomes of human HCC, novel target genes or pathways critically involved in hepatocarcinogenesis may hopefully be identified.

Characterization of hepatitis B virus molecular genotypes in Chongqing and quantitative serological markers in patients during natural phases of chronic hepatitis B infection

BACKGROUND/AIMS

The present study was launched to systematically characterize the molecular genotypes and quantitative serological biomarkers during the natural course of chronic hepatitis B (CHB) infection in a patient population from Chongqing, China.

METHODS

A total of 140 patients were enrolled and grouped according to the natural phases of HBV infection: HBeAg (+) immune tolerance, immune clearance, HBeAg (-) low replicative and reactivation phase. Nested PCR was used for HBV molecular genotyping and chemiluminescent microparticle immunoassay for quantitative serological detection.

RESULTS

Subgenotypes B2 and C2 were found to be most prevalent with genotype B patients showing more potent viral activity. HBsAg level was found to be significantly correlated with HBV DNA, HBeAg, age, ALT and AST levels during some phases of CHB.

CONCLUSION

These results indicated that molecular genotyping and quantitative serological detection might be helpful for earlier prediction of the long-term disease outcomes.

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.

Epidemiological and Clinical Features of Hepatitis B Virus Genotypes among Immigrants in Southern Italy

Background/aims. This study aims to determine the distribution and clinical features of HBV-genotypes in a population of immigrants affected by HBV-infection. Methods. Between 01/2003 and 03/2009, 1623 immigrants were tested for HBV-infection. Biochemical and virological activities were determined in HBsAg-positive patients; HBV-genotypes were determined, by the INNO-LiPA HBV Genotyping, in the subjects with HBV DNA detectable. In every patient we evaluated the stage and classified the infection as inactive carrier, mild or moderate/severe chronic hepatitis, cirrhosis, and/or HCC. Results. Among the tested subjects, 191 (11.7%) resulted HBsAg-positive, and in 144/191 (75.4%) serum HBV-DNA was detectable. The genotype distribution was as follows: 45,13% genotype E, 18,1% genotype D, 15,3% genotype B, 13,2% genotype C, 4,9% genotype A, 3,5% mixed genotypes (A-D). The evaluation of liver disease degree showed that 24.6% patients were inactive carriers of HBV infection, 19.4% presented a immunotolerance phase, 34.5% had mild chronic hepatitis, 13.6% had a moderate/severe chronic hepatitis, 6.3% had cirrhosis, and 1.6% presented HCC. Conclusions. Our study evidences a high prevalence of HBV-infection in immigrants, and the potentiality of migratory flow in the introduction of genotype non-D hepatitis B virus. The Hepatitis B virus genotypes presented significant differences in epidemiological and clinical characteristics.

Viral hepatocarcinogenesis

Hepatocellular carcinoma (HCC) is the fifth most common cancer and the third leading cause of cancer death worldwide. Despite recent advances in the diagnosis and treatment of HCC, its prognosis remains dismal. Infection with hepatitis B virus (HBV) and hepatitis C virus (HCV) are the major risk factors for HCC. Although both are hepatotropic viral infections, there are important differences between the oncogenic mechanisms of these two viruses. In addition to the oncogenic potential of its viral proteins, HBV, as a DNA virus, can integrate into host DNA and directly transform hepatocytes. In contrast, HCV, an RNA virus, is unable to integrate into the host genome, and viral protein expression has a more critical function in hepatocarcinogenesis. Both HBV and HCV proteins have been implicated in disrupting cellular signal transduction pathways that lead to unchecked cell growth. Most HCC develops in the cirrhotic liver, but the linkage between cirrhosis and HCC is likely multifactorial. In this review, we summarize current knowledge regarding the pathogenetic mechanisms of viral HCC.

Hepatitis B virus genotype B has an earlier emergence of lamivudine resistance than genotype C

BACKGROUND

Hepatitis B virus (HBV) genotype B and C seem not to affect the therapeutic response to lamivudine (3TC). Whether a given genotype has an earlier emergence of 3TC resistance remains unclear. We thus conducted this study to elucidate the association of HBV genotype with the emergence of 3TC-resistant strains in Taiwanese patients.

METHODS

Forty chronic hepatitis B patients who developed resistance after 3TC therapy were retrospectively enrolled. HBV genotype, serum alanine aminotransferase (ALT) and HBV DNA levels were determined at baseline. The presence of 3TC-resistant mutations was confirmed by direct sequencing whenever biochemical breakthrough developed.

RESULTS

The distribution of HBV genotype B and C in 40 patients receiving 3TC therapy were 60% and 40%, respectively. The mean interval to detect 3TC-resistant strain was 19.6 +/-1.7 months. By using multivariate analysis, HBV genotype B and higher pre-treatment HBV DNA level were independently associated with earlier detection of 3TC-resistant strains. In addition, genotype B was significantly associated with development of 3TC resistance within the first 12 months of 3TC therapy compared with genotype C (odds ratio 8.27; P=0.004).

CONCLUSIONS

Compared with HBV genotype C, genotype B appears to have an earlier biochemical resistance to 3TC than genotype C. Therefore, more frequent monitoring of viral load or genotypical resistance might be needed for patients with HBV genotype B infection receiving 3TC therapy, especially during the first year.

Current issues in the management of paediatric viral hepatitis

Viral hepatitis poses important problems for children. In preschoolers, hepatitis A virus (HAV) infection frequently causes acute liver failure. Vaccinating toddlers against HAV in countries with high endemicity is expected to decrease mortality. HAV vaccine demonstrates efficacy (comparable to immunoglobulin) as post-exposure prophylaxis. A recently developed vaccine against hepatitis E virus (HEV) may benefit fetal health, because pregnant women are most prone to acute liver failure as a result of HEV. Hepatitis B vaccine continues to demonstrate value and versatility for preventing serious liver disease. With chronic infection, undetectable levels of serum HBV DNA complement e-seroconversion as the preferred outcome measure; suppressed viral load correlates with long-term complications better than HBeAg status. Among Taiwanese children, low pretreatment HBV DNA (<2 x 10(8) copies/ml) strongly predicted response to interferon-alpha. Future paediatric studies must incorporate HBV DNA levels. The rationale for routine treatment of immunotolerant hepatitis B during childhood remains uncertain. Any treatment of chronic hepatitis B in childhood requires consideration of the risks and benefits. Childhood hepatitis C virus (HCV) infection results mainly from mother-to-infant transmission. Babies of HCV-infected women should be tested for serum HCV RNA at 1 month of age. If negative, confirmatory anti-HCV antibody testing may be performed between 12 and 15 months of age. Children with chronic hepatitis C may develop progressive fibrosis/cirrhosis, particularly in the setting of obesity and insulin resistance. Treatment of children chronically infected with genotype 2 or 3 is highly successful: combination therapy of pegylated interferon-alpha and ribavirin is well tolerated and superior to pegylated interferon-alpha alone.

Serum levels of interleukin-10 and interleukin-12 predict early, spontaneous hepatitis B virus e antigen seroconversion

BACKGROUND & AIMS

This prospective cohort study aimed to determine the effect of cytokines on spontaneous hepatitis B e antigen (HBeAg) seroconversion in patients with chronic hepatitis B virus (HBV) infection.

METHODS

Polymorphisms in interleukin (IL)-2, IL-4, IL-10, IL-12beta, and interferon-gamma were evaluated in 288 HBeAg-positive chronic HBV patients (median initial age, 8.6 years; median follow-up duration, 19.3 years). Serum cytokine levels were determined in 154 subjects (53.5%) before and after HBeAg seroconversion by enzyme-linked immunosorbent assay analysis. Peripheral blood mononuclear cells (PBMC) were isolated from patients with chronic HBV infection and stimulated with HBV core antigen (HBcAg); data on cytokine genotypes and phenotypes were compared.

RESULTS

The IL-10-1082 G/G and IL-12beta -10993C/G genotypes predicted early, spontaneous HBeAg seroconversion (hazard ratio [HRs] = 3.43 and 1.54; P < .001, and P < .004, respectively), based on multivariate survival analysis. The IL-10 -1082 G/G genotype was associated with higher serum levels of IL-10 and IL-12; the IL-12beta -10993 C/G genotype predicted higher levels of IL-12 secretion by PBMC after in vitro HBcAg stimulation (P = .04). Higher levels of serum IL-12 (>45 pg/mL) and IL-10 (>70 pg/mL) were associated with early, spontaneous HBeAg seroconversion (HR = 1.52 and 1.48; P = .04 and .02, respectively).

CONCLUSIONS

The IL-10-1082 G/G is associated with higher serum IL-10 and IL-12 levels and IL-12beta -10993 C/G is associated with increased secretion of IL-12 in response to HBcAg stimulation of PBMC. Both genotypes are associated with early, spontaneous HBeAg seroconversion. Higher serum levels of IL-10 and IL-12 in HBeAg-positive patients are correlated with early, spontaneous HBeAg seroconversion.

Global control of hepatitis B virus: does treatment-induced antigenic change affect immunization?

Since its widespread introduction, the hepatitis B vaccine has become an essential part of infant immunization programmes globally. The vaccine has been particularly important for countries where the incidence of hepatitis B virus-related hepatocellular carcinoma is high. Effective treatment options for individuals with chronic hepatitis B infection were limited until 1998 when lamivudine, the first nucleoside analogue drug, was introduced. As a single treatment agent, however, lamivudine has a significant drawback: it induces lamivudine-resistant hepatitis B virus strains that may pose a risk to the global hepatitis B immunization programme. Mutations associated with drug treatment can cause changes to the surface antigen protein, the precise part of the virus that the hepatitis B vaccine mimics. However, the emergence of antiviral drug-associated potential vaccine escape mutants (ADAP-VEMs) in treated patients does not necessarily pose a significant, imminent threat to the global hepatitis B immunization programme. Nonetheless, there is already evidence that current treatment regimens have resulted in the selection of stable ADAP-VEMs. Treatment is currently intended to prevent the long-term complications of hepatitis B virus infection, with little consideration given to potential adverse public health impacts. To address individual and public health concerns, trials are urgently needed to find the optimal combination of existing drugs that are effective but do not induce the emergence of ADAP-VEMs. This paper examines the mechanism of antiviral drug-selected changes in the portion of the viral genome that also affects the surface antigen, and explores their potential impact on current hepatitis B immunization programmes.

Treatment of hepatitis B virus-infected patients: utility of therapeutic recommendations in developing countries

BACKGROUND

The treatment of individuals infected with hepatitis B virus (HBV) is a complex issue in practical settings, despite the explosion of new and effective antiviral agents.

OBJECTIVE

To assess the scope and limitations of ongoing treatment guidelines against HBV from a global perspective.

METHODS

Present therapeutic guidelines against HBV have been discussed with emphasis on their value in developing countries that harbor about 90% of the total number of global patients who are infected with HBV.

RESULTS/CONCLUSION

Treatment of HBV-infected patients should be appropriately followed up and healthcare delivery systems should be able to combat treatment-induced adverse side effects. Current therapeutic guidelines should be optimized based on the socio-economic conditions of developing countries.

A genetic variant of hepatitis B virus divergent from known human and ape genotypes isolated from a Japanese patient and provisionally assigned to new genotype J

Hepatitis B virus (HBV) of a novel genotype (J) was recovered from an 88-year-old Japanese patient with hepatocellular carcinoma who had a history of residing in Borneo during the World War II. It was divergent from eight human (A to H) and four ape (chimpanzee, gorilla, gibbon, and orangutan) HBV genotypes, as well as from a recently proposed ninth human genotype I, by 9.9 to 16.5% of the entire genomic sequence and did not have evidence of recombination with any of the nine human genotypes and four nonhuman genotypes. Based on a comparison of the entire nucleotide sequence against 1,440 HBV isolates reported, HBV/J was nearest to the gibbon and orangutan genotypes (mean divergences of 10.9 and 10.7%, respectively). Based on a comparison of four open reading frames, HBV/J was closer to gibbon/orangutan genotypes than to human genotypes in the P and large S genes and closest to Australian aboriginal strains (HBV/C4) and orangutan-derived strains in the S gene, whereas it was closer to human than ape genotypes in the C gene. HBV/J shared a deletion of 33 nucleotides at the start of preS1 region with C4 and gibbon genotypes, had an S-gene sequence similar to that of C4, and expressed the ayw subtype. Efficient infection, replication, and antigen expression by HBV/J were experimentally established in two chimeric mice with the liver repopulated for human hepatocytes. The HBV DNA sequence recovered from infected mice was identical to that in the inoculum. Since HBV/J is positioned phylogenetically in between human and ape genotypes, it may help to trace the origin of HBV and merits further epidemiological surveys.

Drug targets in hepatitis B virus infection

Hepatitis B virus infection (HBV) is a significant global health problem. Despite the success of universal hepatitis B vaccination in many countries, more than 350 million individuals worldwide are chronically infected and 15- 40% of those will develop cirrhosis and/or hepatocellular carcinoma if left untreated. Available therapies for chronic hepatitis B (CHB) infection are effective at decreasing viremia and improving measured clinical outcomes, however, no single therapy is optimal. As such, alternative drug therapies and the investigation of their role in the management of CHB are warranted. Significant improvements in the understanding of the HBV life cycle, viral genomics, and virus-host interactions continue to lead to the development of novel viral targets and immune modulators. Currently, two major classes of agents are utilized in CHB: the interferons and the nucleos(t)ide analogues. Each agent has individual advantages and drawbacks. The development of specific antiviral therapy has led to the emergence of HBV drug-resistant strains that has limited the long-term therapeutic potential of available agents. This necessitates the development of new agents that target both wild-type and drug-resistant strains. Further understanding of the basic mechanisms and clinical nuances of drug therapy is warranted. As most novel therapies are in the earliest stages of clinical development and testing, in the near future, treatment will continue to be long-term and likely involve the use of combination therapies to prevent viral resistance. In this review, we will highlight the HBV life cycle and genome, focusing in on current and potential novel antiviral drug targets as well as the benefits and clinical challenges with these therapies.

Association of baseline viral factors with response to lamivudine therapy in chronic hepatitis B patients with high serum alanine aminotransferase levels

Background

With the exception of alanine aminotransferase (ALT) level, baseline factors predictive of therapeutic response to lamivudine in patients with hepatitis B e antigen (HBeAg)-positive chronic hepatitis B (CHB) remain unknown. We thus studied the influence of pre-therapy viral factors on end-of-treatment responses to lamivudine.

Methods

A total of 116 treatment-naive HBeAg-positive CHB patients who had pre-therapy ALT level >5x the upper limit of normal (ULN) and received lamivudine for 12–18 months were enrolled. HBeAg seroclearance and combined HBeAg seroclearance, ALT normalization and undetectable hepatitis B virus DNA at the end of therapy were defined as primary and secondary endpoints, respectively. Pre-therapy viral factors including viral load, genotype, precore (PC) stop codon status, basal core promoter status and pre-S deletion were determined to correlate with therapeutic endpoints.

Results

The frequency of patients with detectable PC stop codon mutation (G1896A), basal core promoter mutation (A1762T/G1764A) and pre-S deletion at baseline was 22.4%, 21.6% and 12.1%, respectively. After the end of 12–18 months of lamivudine therapy, the overall HBeAg seroclearance rate was 56.0%. Patients with HBeAg seroclearance had a higher prevalence of baseline PC stop codon mutation than those without (30.8% versus 11.8%; P=0.015). By using multivariate analyses, the odds ratio of patients with the PC stop codon mutation to develop HBeAg seroclearance was 3.33 ( P=0.024). The presence of the PC stop codon mutation also correlated with the combined response.

Conclusions

For lamivudine-treated HBeAg-positive CHB patients with pre-therapy ALT levels >5xULN, the PC stop codon mutation could predict a higher HBeAg seroclearance rate at the end of 12–18 months of therapy.

Hepatitis B therapy in children

Chronic hepatitis B virus (HBV) infection is a major cause of liver disease throughout the world, leading to cirrhosis and hepatocellular carcinoma in many individuals. Children are more likely to develop chronic HBV infection as they demonstrate greater immunotolerance to the virus, and response to therapy in children remains disappointing. Three therapeutic agents for chronic HBV infection in children have been approved in the USA, including standard IFN-alpha, lamivudine and adefovir. IFN-alpha has been the most effective ( approximately 30% hepatitis B e antigen [HBeAg] seroconversion; 10% hepatitis B surface antigen [HBsAg] seroconversion), although benefits are primarily observed in children with alanine aminotransferase levels over two-times the upper limit of normal and must be weighed against significant side effects. Studies comparing the long-term outcome of chronic hepatitis B in children treated with IFN-alpha and in untreated controls show that the rate of anti-HBeAb seroconversion tends to overlap in treated and untreated patients within a few years of follow-up, suggesting that IFN-alpha simply accelerates a spontaneous event. Lamivudine's virologic response rates mirror those of IFN-alpha (23-31% HBeAg seroconversion) with easier administration and a better safety profile but lower HBsAg seroconversion (2-3%) and high rates of drug resistance. Adefovir data show low rates of resistance and a good safety profile, but virologic response was limited to adolescent patients and was lower than that of lamivudine (16% HBeAg seroconversion; <1% HBsAg seroconversion). Entecavir and tenofovir, both approved therapies for adults with chronic HBV infection, are in trials for use in children. Future therapies will probably include these agents as well as combined therapies. Finally, watchful waiting of children is an option since current therapies are only 30% effective at best, although the long-term impact of therapy in childhood on rates of cirrhosis and hepatocellular carcinoma remains unknown.

Direct cytopathic effects of particular hepatitis B virus genotypes in severe combined immunodeficiency transgenic with urokinase-type plasminogen activator mouse with human hepatocytes

BACKGROUND & AIMS

Little is known about the direct cytopathic effect of hepatitis B virus (HBV) and its association with particular viral genotypes or genetic mutations. We investigate HBV genotype-related differences in viral replication, antigen expression, and histopathology in severe combined immunodeficiency transgenic with urokinase-type plasminogen activator mice harboring human hepatocytes.

METHODS

Mice were inoculated with wild-type of different genotype strains (3 for each HBV/A2, B1, and C2) recovered from preinfected-mice sera or patient sera.

RESULTS

Histologic analysis of mice infected with HBV/C2 for 22-25 weeks showed abundant ground-glass appearance of the hepatocytes and fibrosis in the humanized part of the murine liver owing to the activation of hepatic stellate cells mediated by oxidative stress through transforming growth factor-beta1 signaling, whereas neither was observed with HBV/A2 and B1. The HBV-DNA level in sera was the highest in mice infected with HBV/C2 compared with those with HBV/A2 and HBV/B1 (10(9), 10(7), and 10(4) log copies/mL, respectively, P < .05) during 6-8 weeks postinoculation. HB core-related antigen excretion had a similar trend among the genotypes, whereas secretion of HB surface antigen was more pronounced for HBV/A2 followed by HBV/C2 and much less for HBV/B1. Introduction of precore stop-codon mutation in the HBV/B1 caused a significant increase in viral replication, antigen expression, and a histopathologic picture similar to HBV/C2.

CONCLUSIONS

By using a humanized in vivo model, we show that different HBV genotypes and even particular mutations resulted in different virologic and histopathologic outcomes of infection, indicating that particular genetic variants of HBV may be directly cytopathic in immunosuppressive conditions.

Hepatocellular carcinoma: epidemiology, risk factors and pathogenesis

Hepatocellular carcinoma (HCC) is the commonest primary malignant cancer of the liver in the world. Given that the burden of chronic liver disease is expected to rise owing to increasing rates of alcoholism, hepatitis B and C prevalence and obesity-related fatty liver disease, it is expected that the incidence of HCC will also increase in the foreseeable future. This article summarizes the international epidemiology, the risk factors and the pathogenesis of HCC, including the roles of viral hepatitis, toxins, such as alcohol and aflatoxin, and insulin resistance.

Prevalence of HBV genotypes in Central and Eastern Europe

The importance of hepatitis B virus (HBV) genotypes for disease progression and response to interferon-alpha-based treatment is well established. While almost all patients in the Mediterranean area are infected with HBV genotype D, HBV genotype A is dominant in Northern Europe. However, the distribution of HBV genotypes is unknown for several Central and Eastern European countries. Data are described of 1313 HBsAg-positive patients recruited at 14 referral centers in eight countries. There were only very few cases of HBV genotype B, C, E, F, and H infection while HBV genotypes A and D were found in 42% and 48% of patients, respectively. Eight percent of patients had positive bands for more than one genotype using the hybridization assay. The frequency of genotype A was higher in Poland (77%) and the Czech Republic (67%) as compared to Hungary (47%), Lithuania (41%), Croatia (8%), and Germany (32%). In contrast, HBV genotype D was most frequent in Croatian, Romanian, and Russian patients with 80%, 67%, and 93% of cases, respectively. In conclusion, HBV genotype A versus D showed significantly different distribution patterns in Central and Eastern Europe which deserves consideration for national guidelines and treatment decisions.