Hepatitis B genotypes and the response to interferon therapy

Molecular analysis of hepatitis B virus isolates in Mexico: Predominant circulation of hepatitis B virus genotype H

AIM: To determine the genotypes in Mexican hepatitis B virus (HBV) isolates and characterize their precore and core promoter mutations.

METHODS: Forty-nine HBV isolates of Mexico obtained from sera of 15 hepatitis patients, 6 hemodialysis patients, 20 men seeking HIV testing, and 8 AIDS patients were analyzed. HBV isolates were amplified by PCR, and genotyped by line probe assay (INNO-LiPA HBV Genotyping; INNOGENETICS N V, Ghent, Belgium). HBV genotype confirmation was performed by DNA sequencing part of the sAg region. Precore and core promoter mutation characterization was performed by line probe assay (INNO-LiPA HBV PreCore; INNOGENETICS N V, Ghent, Belgium).

RESULTS: Overall, HBV genotype H was found in 37 (75.5%) out of the 49 isolates studied. HBV genotypes G, A, and D were found in 5 (10.2%), 4 (8.2%), and 3 (6.1%) isolates, respectively. HBV genotype H was predominant in isolates from hemodialysis patients (100%), hepatitis patients (80%), and men seeking HIV testing (75%), and accounted for half of infections in AIDS patients (50%). Six (12.2%) out of the 49 HBV isolates showed both wild type and mutant populations at precore codon 28. These mixed wild type and precore mutant populations were observed in one HBV genotype A isolate and in all HBV genotype G isolates. A dual variant core promoter mutation was observed in 1 (2%) of the isolates, which was genotype H.

CONCLUSION: HBV genotype H is highly predominant in HBV isolates of Mexico followed by genotypes G, A and D. A low frequency of precore and core promoter mutations is observed in HBV Mexican isolates.

Recommendations and potential future options in the treatment of hepatitis B

The natural history of chronic hepatitis B should be clearly defined before appropriate recommendations for treatment can be advocated. In patients who acquire the disease in early life, the complications of chronic hepatitis B continue to occur as a result of prolonged insidious damage to the liver, even in the low viraemic phase. Treatment that ends with hepatitis B e antigen seroconversion with hepatitis B virus DNA levels just below 10(5) copies/ml may not be sufficient. Patients with mild elevation of alanine aminotransferase levels are already at considerable risk of developing complications. Treatment strategy should aim at maximal and prolonged viral suppression to the lowest possible hepatitis B virus DNA levels. Nucleotide/nucleoside analogues will become the mainstay of treatment. Future treatment strategic plans should target maximising antiviral potency and minimising the chance of drug resistance.

Genetic structural differences between responders and non-responders to interferon therapy for chronic hepatitis-B patients

Interferon-alpha therapy has become a main stay of treatment for hepatitis-B patients. The sustained remission rates are around 30%, and the factors determining response are poorly defined. Our study aimed to search for the genetic differences between responder and non-responder patients. We have found 13 short tandem repeat markers (STR) that display different allele and/or genotype frequency between the two patient groups. Eleven out of 13 STR markers were selected to perform principal component analysis and hierarchical clustering. The study subjects could be further divided into six groups based on their genetic similarity, which correlated with the drug response rate. In conclusion, this pilot study has developed a new approach to identify genetic markers that allows us to predict the drug response in hepatitis B patients. Our study utilizing STR markers may provide an alternative approach to the utilized SNP markers in pharmacogenetic study.

Interferon-alpha therapy in HBeAg-negative chronic hepatitis B: a long-term prospective study from north-western Greece

AIMS

To determine the long-term response to interferon-alpha therapy in patients with hepatitis B e antigen-negative chronic hepatitis B, and the factors independently associated with response and survival.

METHODS

Sixty-three patients with documented hepatitis B e antigen-negative chronic hepatitis B treated with interferon-alpha for a year were followed-up for a period of 6 years.

RESULTS

Sustained biochemical and virological response was seen in 34.91% and 33.33% of patients at 6 and 12 months of follow-up, respectively, and histological improvement in 54.5% of sustained responders compared with non-responders (7.1%, P = 0.004, chi-squared test), at 6 months of follow-up. Multivariate analysis showed that patients with hepatitis B virus-DNA levels at 6 months of treatment <10,000 copies/mL had a low probability of relapse, compared with those with levels >10 000 copies/mL (P = 0.032). Age (>65 years) and hepatitis B virus-DNA level at 6 months of treatment (>10,000 copies/mL) were the independent factors for disease progression and survival (P = 0.041 and P = 0.044 respectively). At 6 years, a sustained response was still present in 19.04% of patients and 4.8% of them had developed anti-HBs.

CONCLUSION

Hepatitis B virus-DNA monitoring by quantitative polymerase chain reaction at 6 months of treatment may allow for early prediction of response to interferon-alpha, and may serve as an indicator of disease progression in the future.

Treatment of chronic hepatitis B in children

Chronic hepatitis B infection remains a significant health problem worldwide, and acquisition during infancy or childhood causes many of the chronic infections that are responsible for the morbidity associated with this disease. Some children with chronic hepatitis B are candidates for treatment. Two medications are currently licensed for use in children, and it is anticipated that others will be available in the next several years. This article describes rationale for treatment, patient selection and pros and cons of the current and expected therapeutic options.

[Successful lamivudine therapy for chronic hepatitis B in the family]

BACKGROUND

Hepatitis B virus infection is a global public health problem since it is a leading cause of liver cirrhosis and hepatocellular carcinoma. An optimal treatment is needed to reduce mortality. Current therapies for chronic hepatitis B include standard and pegilated interferon-alfa and nucleoside and nucleotide analogies, primarily lamivudine and adefovir. Each of the therapies, however has various limitations.

CASE REPORT

In this paper we presented a father and his daughter with chronic hepatitis B, successfully treated with lamivudine.

CONCLUSION

In the linked cases of chronic hepatitis B, the choice of antiviral medicine in some patients could also be made on the basis of its efficacy in the persons previously treated with it, even without determining virus genotype.

Hepatitis B virus genotypes in children with chronic hepatitis B in Poland

OBJECTIVES

To analyse the distribution of HBV genotypes in Polish children with chronic hepatitis B, and to assess the relation between the viral genotype and the severity of liver damage.

METHODS

Serum samples from children with chronic hepatitis B were used for biochemical and serological testing, and for determination of HBV genotypes by a nested-multiplex-polymerase chain reaction. Liver biopsies were obtained for histological assessment, which was performed according to the Batts and Ludwig scoring system of chronic hepatitis.

RESULTS

Of 78 children with chronic hepatitis B, 74 had an identifiable HBV genotype: 86.5% were infected with genotype A, and 13.5% were carriers of genotype D. The frequency of HBeAg clearance and the levels of alanine aminotransferase and serum aspartate transaminase were comparable in both genotype groups. There was no correlation between the HBV genotype and either activity of liver inflammation or liver fibrosis.

CONCLUSIONS

This study shows that the distribution of HBV genotypes in Polish children with chronic HBV infection reflects the general prevalence of HBV genotypes in Europe. The course of chronic hepatitis B in children is not significantly influenced by viral genotypes A or D.

Clinical Significance of the Genotype and Core Promoter/Pre-Core Mutations in Hepatitis B Virus Carriers

It has been shown that clinical and virological characteristics vary among hepatitis B virus (HBV) genotypes. In this study, we measured the virus level, disease severity, and presence or absence of core promoter (CP)/pre-core (PC) mutations in 241 HBV carriers, and investigated the clinical significance of measuring the HBV genotype. In genotype C HBV carriers, the proportion of hepatitis B e antigen (HBeAg)-positive patients was significantly higher than that in genotype B HBV carriers (0 vs. 34.4%, p < 0.05), and the virus level was higher (4.9 vs. 4.05 LGE/ml). In the genotype B HBV carriers, the incidence of PC mutation was significantly higher (69 vs. 34%, p < 0.05). In the genotype C HBV carriers, the incidence of CP mutation was significantly higher (13 vs. 78%, p < 0.05). We compared patients with the wild (W)/mutant (M) pattern in the CP/PC regions to those with the M/W pattern in the CP/PC regions among the genotype C HBV carriers. Both the proportion of HBeAg-positive patients (65.8 vs. 15.4%, p < 0.05) and the alanine aminotransferase (ALT) level (48 vs. 21.5 IU, p < 0.05) were higher in the patients with the M/W pattern in the CP/PC regions, and the disease severity was deteriorated. In conclusion, genotype B HBV may more frequently induce HBe seroconversion via PC mutation compared to genotype C HBV. Among the genotype C HBV carriers, hepatitis activity and the deterioration of the disease severity were significantly inhibited in the group in which PC mutation initially occurred, in comparison to the group in which CP mutation initially occurred.

Evaluation of 10 commercial diagnostic kits for in vitro expressed hepatitis B virus (HBV) surface antigens encoded by HBV of genotypes A to H

Genetic variability of the hepatitis B virus (HBV) constitutes one of the major challenges for diagnosis of HBV infection. It is plausible that amino acid substitutions in the "a" determinant of the HBV surface antigen (HBsAg) that affect antigenic sites, whether originating from genetic diversity or from mutations in the HBV strain itself, will affect the sensitivity of some diagnostic kits. In fact, recent studies have indicated that some diagnostic kits had false negative results with particular HBsAg mutants. There have been, however, few substantial studies evaluating sensitivities of diagnostic kits to the HBsAg encoded by different HBV genotypes. Our recent study found that 10 diagnostic kits available in Japan were able to detect HBsAg irrespective of whether it originated from HBV genotypes A, B or C, with the latter two genotypes being the dominant species in East Asia. In this study, we extended our previous efforts by assessing the ability of diagnostic kits to detect recombinant HBsAg derived from HBV genotypes A to H. Our results demonstrated that 9 out of 10 diagnostic kits evaluated were able to detect as low as 0.2 International Units (IU)/ml HBsAg, irrespective of HBV genotype. The genotypic differences in the HBV family thus appear to have little impact on the sensitivity of currently available HBsAg diagnostic kits.

Genotypes and viremia of hepatitis B and D viruses are associated with outcomes of chronic hepatitis D patients

BACKGROUND & AIMS

Genotypes and viremia of hepatitis D virus (HDV) and hepatitis B virus (HBV) may be associated with outcomes. This study evaluated the impact of viral genotypes and viremia on outcomes of dual HBV and HDV infection.

METHODS

Viremia and viral genotypes were analyzed in 194 consecutive chronic hepatitis B patients with HDV superinfection and correlated with outcomes.

RESULTS

The numbers of HBV genotype A, B, C, and nonclassified were 4, 57, 23, and 110, respectively. There were 51 genotype I HDV, 74 genotype II HDV, 8 genotype IV HDV, and 61 nonclassified HDV genotype. In a median follow-up of 135 months, 24 progressed to cirrhosis and 41 developed hepatocellular carcinoma. Patients infected with genotype I HDV had a lower remission rate (15.2% vs 40.2%; P = .007) and more adverse outcomes (cirrhosis, hepatocellular carcinoma, or mortality) (52.2% vs 25.0%; P= .005) than those with genotype II HDV. Patients infected with genotype C HBV had a lower remission rate (0 vs 32.1%; P = .005) and more adverse outcomes (70.0% vs 33.9%; P = .005) than those with genotype B HBV. The presence of HBV or HDV viremia was associated with lower remission rates compared with those negative for both (26.4% and 24.3% vs 69.2%; P < .001). In multivariate analysis, age, genotype C HBV, and genotype I HDV were independent factors associated with adverse outcomes.

CONCLUSIONS

In chronic HBV and HDV dual infections, older age, genotype I HDV, and genotype C HBV correlated with adverse outcomes.

Hepatitis B virus drug resistance: mechanism and clinical implications for the prevention of treatment failure

Hepatitis B virus (HBV) infection remains a major public health problem worldwide. Recently, the research efforts to identify new inhibitors enabled the development of antiviral agents to treat patients chronically infected by HBV. In clinical practice, the use of nucleoside analogs, which inhibit viral polymerase activity, induces suppression of viral replication accompanied by an improvement in biochemical and histological conditions in most patients. However, many clinical studies revealed the emergence of drug-resistant mutants during extended treatment. This review focuses on the mechanism of HBV drug-resistant mutant selection and on the clinical implications of HBV drug resistance for the prevention of treatment failure.

Multicentre study of hepatitis B virus genotypes in France: correlation with liver fibrosis and hepatitis B e antigen status

The clinical significance of hepatitis B virus (HBV) genotypes is still under debate. The aims of this study were to assess the distribution of HBV genotypes in France and to identify the associations between HBV genotypes and patient demographics, severity of liver disease and HBeAg status in patients referred to tertiary care centres. This was a French, multicentre, retrospective study on 262 patients with chronic HBV infection. HBV genotypes were determined using INNO-LiPA. Liver fibrosis damage was evaluated by histological analysis of biopsy samples. Patients were mainly male (74%), of Caucasian (65%), Asian (17%) or African (18%) ethnicity and 36% were HBeAg positive. All A-G genotypes were found, the most frequent being genotypes D (27%) and A (24%), followed by E (13%) and C (12%), and B (7%). Mixed genotypes were detected in 16% of the cases. Genotype A was associated with sexual contact (P < 0.001) and genotype D with transfusion (P < 0.001) and HBe antibody positivity (P = 0.03).The distribution of HBV genotypes differed with regard to the ethnicity, and may reflect migration patterns. Genotypes A and D were the most frequent in France. Genotype A was associated with HBeAg positivity and genotype D with HBe antibody positivity. In our European patients, we find no clear association between a given HBV genotype and liver disease severity.

Interferon alpha-2b with and without ribavirin in the treatment of hepatitis B e antigen-positive chronic hepatitis B: a randomized study

To study whether interferon (IFN) alpha and ribavirin combination therapy has a beneficial effect for hepatitis B e antigen (HBeAg)-positive chronic hepatitis B, we enrolled 119 such patients in a randomized study. Fifty-nine patients received 5 million units of IFN-alpha2b daily for 4 weeks followed by 5 million units three times a week for 28 weeks, plus 1,200 mg ribavirin daily. Sixty patients received the same dosage of IFN plus placebo. They were followed up for 24 weeks posttreatment, and 105 patients (88%) completed the entire course of 56 weeks. By intention-to-treat analysis, the rate of combined response (serum hepatitis B virus [HBV] DNA <2.5 pg/mL and HBeAg seroconversion) was 17% versus 25% between the IFN/ribavirin and IFN/placebo group, respectively, at the end of treatment (P = .35) and 25% vs. 20% at the end of follow-up (P = .32). Using quantitative real-time polymerase chain reaction assay, the log10 reduction of serum HBV DNA was 1.05 +/- 1.72 (mean +/- SD) versus 1.29 +/- 1.91 between the two groups at the end of treatment (P = .49) and was 2.15 +/- 2.15 versus 1.21 +/- 2.48 at the end of follow-up (P = .04). Prolonged observations in 83 patients suggested that the combined response was 29% (n = 17) versus 20% (n = 12) at 48 weeks after the end of treatment, respectively (P = .17). The safety profile was similar, except that the IFN/ribavirin group had a higher risk of anemia (15% vs. 0%; P = .002). In conclusion, for the treatment of HBeAg-positive chronic hepatitis B, adding ribavirin does not seem to increase the efficacy of IFN.

Molecular epidemiology of hepatitis B virus in Latin America

Hepatitis B virus (HBV) is an etiological agent of acute and chronic liver disease existing throughout the world. The high genetic variability of HBV is reflected by eight genotypes (A to H), each one with a particular geographical prevalence. The global pattern of HBV genotypes is associated with the distribution of human populations among the different continents and may reflect the patterns of human migrations. Genotypes F and H are considered indigenous to Latin America. The most prevalent genetic group of Central and South America, genotype F, is subdivided into two subtypes and five clusters associated with defined geographic areas. Genotype H has been described in Mexico and Central America. This pattern provides a tool to reconstruct the initial immigration of ancestral Amerindians from Asia and their further spread through Central and South America. Other HBV genotypes found in different Latin American countries may reflect migration from other geographical areas into the region. Genotypes A and D are the signature of the European colonization that started in the sixteenth century, including slave trade from Africa. Genotypes B and C indicate the arrival of people from Southeast Asia. The impact of HBV genotypes on the natural course of HBV infection and response to treatment has been studied recently and controversial results have been obtained. The majority of the current information concerns with genotypes B and C. In contrast, very few data are available on the Latin American HBV genotypes F and H. It has been reported that liver failure and death may be more frequent in patients infected with genotype F. More studies are needed to assess the association between H13V genotypes and clinical course of infection, especially in Latin America.

Evolution of Hepatitis B virus in an acute hepatitis B patient co-infected with genotypes B and C

The interactions between different genotypes of Hepatitis B virus (HBV) in co-infected patients remain largely unknown, especially in acute infection. Here, the evolution of HBV strains was studied in an acute, self-limited hepatitis B patient co-infected with genotypes Ba (B2) and C. Virological analyses were performed at four time points after admission: T1 (5 days), T2 (11 days), T3 (22 days) and T4 (260 days). A dominant-genotype change from genotype C to Ba was found after anti-HBV e antigen (anti-HBe) seroconversion. Further clonal and phylogenetic analyses of the pre-S and pre-core/core regions of HBV were carried out to clarify the interactions between genotypes Ba and C. All clones propagated from T1 and T2 were of genotype C. In contrast, clones propagated from T3 (after anti-HBe seroconversion) were of genotype Ba, C and/or recombinant within the pre-S region. At T4, all clones were of genotype Ba with a 123 bp (from nt 3147 of the pre-S1 region to nt 54 of the pre-S2 region) in-frame pre-S deletion and had lost the start codon of the middle envelope protein and the nucleocapsid-binding site. Phylogenetic analysis showed that genetic distance was greater at T3 after seroconversion to anti-HBe. By using SimPlot, the breakpoint of one pre-S recombinant was located at nt 3069-3100 and the other two at nt 49-87. In conclusion, HBV genotype Ba may overtake genotype C as the predominant strain after anti-HBe seroconversion in acute hepatitis B. Recombination within the pre-S region emerged transiently and the pre-S deletion mutant was finally cleared.

Hepatitis B post-partum e antigen clearance in hepatitis B carrier mothers: Correlation with viral characteristics

BACKGROUND

The purpose of the present paper was to correlate hepatitis B virus (HBV) genotype, e antigen titer, HBV-DNA level and precore/basal core promoter mutations with post-partum e antigen clearance in hepatitis B e antigen (HBeAg)-positive carrier mothers.

METHODS

A total of 40 consecutive HBeAg-positive carrier mothers were studied from January 2002 to January 2003. The blood samples were taken at delivery, 3-4 months and at 1 year after delivery, and the follow-up period was until 1 year after delivery. All sera were assayed for HBeAg, HBV-DNA level, HBV genotype and precore/basal core promoter mutations. The correlation between HBV characteristics and post-partum e antigen clearance was analyzed by Mann-Whitney, Pearson chi2 and multiple logistic regression tests.

RESULTS

The mean age of the 40 HBeAg-positive carrier mothers was 29.9 +/- 5.3 years with a mean parity of 1.4 +/- 0.7. Five of them (group I) had post-partum e antigen clearance, which persisted thereafter, whereas the remaining 35 carrier mothers (group II) had persistent positivity of HBeAg during the follow-up period. The prepartum comparisons of HBV characteristics between groups I and II were comparable in terms of demographics and distributions of HBV genotype and precore/basal core promoter mutations. In contrast, group I carrier mothers had lower HBeAg titer and HBV-DNA level than group II carrier mothers (1:80 vs 1:4000, P = 0.02, and 3.75 x 10(5) vs 3 x 10(8) copies/mL, P = 0.028, respectively).

CONCLUSIONS

Post-partum e antigen clearance in HBeAg-positive carrier mothers is closely associated with prepartum low HBeAg titer or HBV-DNA level.

Significance of hepatitis B virus genotypes A to E in a cohort of patients with chronic hepatitis B in the Seine Saint Denis District of Paris (France)

The aim of this study was to examine the genetic variability of the hepatitis B virus (HBV) and its significance. HBV genotypes, core promoter and precore mutants were characterized in 109 consecutive patients with biopsy-proven HBV chronic hepatitis. Genotypes A (26.6%), B (12.8%), C (18.3%), D (18.3%), and E (14.7%) indicate a wide genotypic distribution. Patients were from Asia (30.3%), Europe (28.4%), Sub Saharan Africa (23.9%), the Caribbean (10.1%), North Africa (5.5%), and Madagascar (1.8%). HBV genotypes A and D (HBV/A and /D) infected all subgroups except Asian patients. HBV/B or /C were found in 97% of Asian patients, whereas HBV/E only infected sub-Saharan African and Caribbean patients. Differences according to genotypes were: an increased prevalence of anti-HBe antibodies in patients infected with HBV/D (P = 0.003), higher serum transaminases in patients infected with HBV/A and/D (P = 0.043), more severe liver fibrosis in patients infected with HBV/A, /C and/D (P = 0.02). Precore and core promoter mutants were found in 87% of anti-HBe positive patients, and were associated with HBV/D (P = 0.04) and severe liver fibrosis (P = 0.002). It is concluded that HBV genotypes A, B, C, D, and E circulate in the Seine Saint Denis District, reflecting the geographical origin of patients. HBV/A, /C and/D seem to be associated with more severe hepatic disease.

The effect of pegylated interferon-alpha on the treatment of lamivudine resistant chronic HBeAg positive hepatitis B virus infection

BACKGROUND/AIMS

To determine the response to pegylated interferon-alpha treatment of HBeAg-positive hepatitis B patients with proven lamivudine resistance.

METHODS

Sixteen HBeAg-positive HBV patients with YMDD mutations were treated with pegylated interferon. Median treatment duration was 52 weeks (range 20-53), with a 26-week follow-up.

RESULTS

Two of 16 (12.5%) patients seroconverted to HBeAg negative and achieved sustained virological (HBV-DNA levels below 10log 5 copies/ml) together with biochemical (normalization of serum ALT levels) responses. Compared with the strong signal in all other patients, only these two patients had a faint signal in the lamivudine resistance assay. For all patients, the median viral load decreased from 10log 9.4 to 7.9 copies/ml (P = 0.001) during treatment but rebounded to a median of 10log 8.7 copies/ml after treatment cessation. Similarly, elevated median ALT levels at baseline decreased with treatment but rebounded after the end of treatment.

CONCLUSIONS

In the largest cohort study to date, pegylated interferon-alpha therapy showed marginal efficacy in the presence of lamivudine resistance but such therapy may be beneficial in patients with only small amounts of mutant virus. In our opinion, an analysis of the patient subgroup harbouring an YMDD-mutation should be included in all future studies of pegylated interferon-alpha in chronic hepatitis B.

Assessment and Management of Chronic Hepatitis B

An understanding of the natural history of CHB is critical for the management of the liver disease. Three clinical patterns with different clinical outcomes are recognized: HBeAg-positive CHB, HBeAg-negative CHB,and inactive CHB. Patients with elevated aminotransferase levels and HBV DNA greater than 105 viral copies per mL in serum and with features of chronic hepatitis on liver biopsy are candidates for therapy regardless of HBeAg status. Multiple host and viral factors and safety profiles of current therapies need to be considered carefully before recommending therapy. There appears to be no role for HBV genotyping in the management of patients. Three antiviral agents are approved for use against CHB infection:IFN-a, lamivudine, and adefovir. Efficacy is moderate at best and is limited by the poor tolerability of IFN and the development of resistance, coupled with concerns regarding the long-term safety with nucleoside analogs. Several new nucleoside and nucleotide analogs and novel agents are at various stages of development as potential therapies for CHB. The ideal compound would be one that is active against all replicative intermediates of the virus and has a low toxicity profile. Despite current shortcomings, the future of therapy for HBV is promising, as newer therapeutic options are being developed based on an understanding of the HBV life cycle.

Major role of hepatitis B genotypes in liver fibrosis during coinfection with HIV

BACKGROUND

Little is know about the determinants of liver fibrosis progression and genomic variability in hepatitis B virus (HBV) in HIV/HBV-coinfected patients.

METHODS

A cross-sectional analysis examined common characteristics of HBV infection in an ongoing cohort study of 308 patients with both HIV-1-positive Western blot and plasma HBV surface antigen (HBsAg) seropositivity. Risk factors for liver fibrosis were studied in a subset of 104 patients for whom liver biopsy and complete HBV genomic analysis were available. Analysis was performed by exact multiple regression analysis.

RESULTS

Mean age of the study population was 40.3 years, with a ratio male to female of 5.3 and a mean duration of HIV infection of 9.3 years. In the subset of 104 patients, plasma HBV e antigen (HBeAg) in HBV-replicative patients could not be detected in 28.4% and lamivudine-resistant mutants were detected in 67.8%. HBV genotype A was the most frequent genotype (73/104) and 25 patients were infected by the usually rare genotype G. METAVIR fibrosis score was rated F2-F4 in 70 patients. After adjustment for the most common known determinants of liver fibrosis, HBV genotype G [odds ratio (OR), 12.60; 95% confidence interval (CI), 1.72-infinite; P < 0.009], efavirenz exposure (OR, 3.55; 95% CI, 1.14-12.14; P < 0.03), and the duration of HIV infection (3.86; 95% CI, 1.27-12.64; P < 0.01) were strongly associated with the risk of grade F2-F4 fibrosis.

CONCLUSION

HBV genotype G is a determinant of liver fibrosis in HIV/HBV-coinfected patients and HBV genotyping should be considered as part of the management of patients with multiple risk factors for rapid progression of liver fibrosis.

Hepatitis B and C in children: current treatment and future strategies

A large proportion of chronic hepatitis B virus (HBV) infections are acquired during childhood. Fewer chronic hepatitis C virus (HCV) infections occur in children than in adults, but thousands of children worldwide have this serious infection. Optimal treatment strategies for these chronic infections in children have not been determined, because data on the natural history are limited. Few medications are currently approved for use in this population. This article discusses how chronic viral hepatitis differs in children and adults in epidemiology, natural history, progression of disease, and response to treatment. Treatment options are discussed, including patient selection, specific medications, ongoing studies, and future treatment options.

Therapy of hepatitis B -- viral suppression or eradication?

The practicing clinician is currently faced with a number of treatment options for chronic hepatitis B. Beginning in 1998 with the licensing of lamivudine and subsequently adefovir, the treatment paradigm shifted from 4 to 6 months of conventional alfa interferon to a year of nucleoside analog therapy. However, prolonged treatment with nucleoside analogs is often needed to optimize virological response. Recently, a 48-week regimen of pegylated interferon for hepatitis B e antigen (HBeAg)-positive and HBeAg-negative chronic hepatitis B has been shown to be effective, and long-term nucleoside analog therapy has been demonstrated to maintain viral suppression. These findings have added to the complexity of decision-making and have raised questions about whether a finite course of pegylated interferon or nucleoside analog therapy, with possible long-term maintenance, is better as first-line therapy. Each of these fundamentally different approaches has advantages and limitations, and both have a place in the therapeutic armamentarium against chronic hepatitis B. Long-term therapy with nucleoside analogs, however, raises a number of practical concerns that have not been fully addressed as of yet. I will present evidence in support of the recommendation that antiviral therapy should ideally be directed toward achieving the highest rate of viral clearance with the shortest interval of treatment.

Advancing patient care: integrating new data

Physicians involved in the management of patients with chronic hepatitis B infection are frequently faced with complex clinical issues concerning the diagnosis, investigation, and treatment of patients. Guidelines exist within the literature that help with decision making; however, in practice individual nuances are often encountered necessitating decisions that go beyond the current guidelines. Following presentation of the available data, a panel of expert hepatologists and gastroenterologists sought to identify and solve challenges that are faced by clinicians in the daily management of patients with chronic hepatitis B infection. The following summary provides an overview of the outcome of these discussions. Because of the complexities of clinical management, the recommendations reflect the opinion of the majority; however, many recommendations were not unanimous. Furthermore, the recommendations that follow are limited to adult patients; the treatment of children was not discussed. A number of issues were identified, and statements concerning possible management strategies that could be applied were developed.

Combined lamivudine/interferon-alpha treatment in "immunotolerant" children perinatally infected with hepatitis B: a pilot study

OBJECTIVE

To investigate whether combining the antiviral effect of lamivudine with the immune-boosting action of interferon-alpha (IFN-alpha) is effective in treating hepatitis B virus (HBV) "immunotolerant" children.

STUDY DESIGN

Twenty-three children (8 boys; mean age, 10 years) infected during the first year of life (17 Asian, 21 with normal aminotransferase levels, 15 with HBV-DNA >1000 pg/mL by hybridization and all with mild histologic changes) were treated with lamivudine (3 mg/kg) for 8 weeks alone and then lamivudine (3 mg/kg) and IFN-alpha (5 MU/m(2), 3 times weekly) in combination for 10 months.

RESULTS

Seventy-eight percent became HBV-DNA negative at the end of treatment, 5 (22%) seroconverted to anti-HBe, 4 (17%) of whom achieved complete viral control, becoming persistently HBsAg negative and anti-HBs positive. None had YMDD mutations. The viral status of the patients has not changed after a median follow-up of 40 months (range, 36 to 48).

CONCLUSIONS

This pilot study suggests that lamivudine pretreatment followed by a combination of lamivudine and IFN-alpha can induce complete viral control in HBV immunotolerant children, hitherto considered poor responders.

Treatment with Peg-interferon alpha-2b for HBeAg-positive chronic hepatitis B: HBsAg loss is associated with HBV genotype

BACKGROUND AND AIMS

Hepatitis B surface antigen (HBsAg) loss is the hallmark of a complete response to antiviral therapy for chronic hepatitis B. In this study, we investigated the frequency of HBsAg loss after treatment with pegylated (Peg)-interferon alpha-2b.

METHODS

In a multicenter randomized controlled trial, 266 HBeAg-positive patients were treated for 52 wks with Peg-interferon alpha-2b (100 microg/wk) in combination with either lamivudine (100 mg/day) or placebo. Posttreatment follow-up was 26 wks.

RESULTS

At the end of follow-up, 95 (36%) of the 266 patients exhibited HBeAg loss, 18 (7%) HBsAg loss, and 16 (6%) HBsAg seroconversion. Addition of lamivudine did not enhance HBeAg loss, HBsAg loss, or development of anti-HBs. All 18 patients who showed HBsAg loss had normal ALT; 11 (61%) of these patients were also hepatitis B virus (HBV) DNA negative (<400 copies/mL) at the end of follow-up. Loss of HBsAg differed according to HBV genotype: 14% for genotype A, 9% for genotype B, 3% for genotype C, and 2% for genotype D (A vs D: p = 0.006).

CONCLUSIONS

One year of Peg-interferon alpha-2b for HBeAg-positive patients led to HBsAg loss in 7%. Our study indicates that treatment with Peg-interferon alpha-2b is the best therapy to achieve HBsAg clearance in patients with genotype A.

Therapeutic options for chronic hepatitis B: considerations and controversies

Five agents are currently approved for the treatment of chronic hepatitis B infection. This article will discuss the three agents for which the most extensive data are available; interferon (IFN), lamivudine, and adefovir, while the following article by Dr. Jules Dienstag will discuss the recently marketed agents, entecavir and peginterferon alfa-2a. The advantages of IFN are its finite duration of therapy (4-6 months), lack of emergence of resistance, and durability of response. On the negative side, response to IFN is less durable in patients with HBeAg-negative chronic hepatitis B virus (HBV). Also, use of IFN is limited by adverse effects and the mode of administration (daily to thrice-weekly subcutaneous injection). Lamivudine and adefovir are orally administered and have good tolerability and safety. Even in patients who experience a marked decrease in serum HBV DNA and loss of HBeAg, oral therapy needs to be continued for at least 6 months, to avoid the risk of reappearance of HBeAg and viremia. Rates of HBeAg seroconversion to anti-HBe-positivity increase with duration of lamivudine or adefovir therapy. The likelihood of development of resistance to lamivudine and associated viral breakthrough limits its long-term use. In patients with HBeAg-negative chronic hepatitis B, long-term therapy is usually required, as off-treatment relapse is common. The emergence of resistance to adefovir is delayed and infrequent, hence adefovir may be preferred in patients requiring long-term therapy.

Genotyping of hepatitis B virus (HBV) by oligonucleotides microarray

Oligonuleotides (oligo) microarray is a promising method for virus genotyping. In this study, we developed an oligo microarray used for genotyping hepatitis B virus (HBV). It consists of 15 probes targeting HBV genotypes A-G and two genotypes of apes, and one conserved probe selected from the HBV pre-S region. To test a clinical sample, the gene targets of clinical samples were amplified and labelled with Cy5-dCTP in a PCR reaction using primers covering the flanking region of the HBV pre-S gene. Following purification, the labelled PCR products were hybridized to the microarray. In an analysis of 96 HBV patients' serum samples using our developed microarray, we identified 34 genotype B, 60 genotype C and 2 genotypes B/C coinfection samples. Sequencing results of 24 randomly selected samples agreed 100% with microarray data. Geographic distribution of genotypes C and B was also divergent, 95.7% (44/46) of genotype C and 64.0% (32/50) of genotype B samples were collected from Northern and Southern China, respectively. The accuracy of genotyping was confirmed by analyzing DNA sequences of 24 samples. It is demonstrated that low-density oligo microarray can serve as a reliable and time-saving method to HBV genotyping from patient's sera.

Nonresponse to 18-month Lamivudine Monotherapy in Chronic Hepatitis B Patients with Dual Genotype B and C Infection and Acute Exacerbation

Molecular epidemiologic studies have indicated the possible existence of mixed infection of different hepatitis B virus (HBV) genotypes in chronic hepatitis B (CH-B) carriers, but the effect of dual HBV genotype B and C infection on the efficacy of lamivudine therapy remains unclear. We report four CH-B patients with dual HBV genotype B and C infection and acute exacerbation who received lamivudine monotherapy for about 18 months. None of them had achieved a sustained response at the end of the 18-month trial of treatment.

Established and emerging therapies for the treatment of viral hepatitis

Patients who are chronically infected with either hepatitis B or C viruses run the risk of developing cirrhosis and hepatocellular carcinoma in later life. Antiviral treatment offers the only means of interrupting this progression. To date, recombinant interferon alpha and the nucleos(t)ide analogues lamivudine and adefovir dipivoxil are the only licensed drugs for the treatment of chronic hepatitis B, whilst recombinant or pegylated interferons in combination with ribavirin are the ones used for chronic hepatitis C virus infections. The efficacy of these treatments, reasons for treatment failure, drug resistance and future options are discussed in the present review.

Hepatitis B virus genome variability and disease progression: the impact of pre-core mutants and HBV genotypes

The hepatitis B virus (HBV), a member of the Hepadnaviridae family, is prone to mutations due to its asymmetric replication via reverse transcription of an RNA intermediate. The estimated mutation rate of the hepadnavirus genome is 2 x 10(4) base substitutions/site/year. This mutation rate is approximately 100 times higher than that of other DNA viruses but between 100 and 1000 times lower than that of RNA viruses. Analyses of both naturally occurring viral variants and in vitro mutagenesis studies have identified some mutations that have a role in viral latency, pathogenesis of liver disease, immune escape, and resistance to antiviral therapy.

Therapeutic implications of hepatitis B virus genotypes

BACKGROUND/AIMS

Hepatitis B virus (HBV) is a global health problem. In addition to the implementation of universal hepatitis B vaccination, effective and individualized treatment of chronic hepatitis B to prevent progression into end-stage liver diseases and hepatocellular carcinoma is still needed. HBV has been designated eight genotypes (A-H) based on genome sequence divergence. The epidemiology of HBV genotypes and their implications on the responses to antiviral therapy have become increasingly recognized in both Asian and Western countries.

METHODS

Published data are thus reviewed.

RESULTS

Each genotype has its distinct geographical and ethnic distribution. Genotypes A and D occur frequently in Africa, Europe, and India, while genotypes B and C are prevalent in Asia. Genotype E is restricted to West Africa, and genotype F is found in Central and South America. The distribution of genotypes G and H is less clear. Accumulating evidence indicates a better sustained response to conventional interferon in patients with genotype B than those with C, and in patients with genotype A than those with D. In contrast, conflicting results exist regarding the response to pegylated interferon. On the other hand, the therapeutic responses to nucleoside/nucleotide analogues are comparable among patients with different HBV genotypes. The impact of HBV subgenotypes, mixed genotype infections, and recombinants of different genotypes on the response to antiviral treatments awaits further examinations.

CONCLUSION

Remarkable clinical and pathogenic differences do exist among HBV genotypes; however, researches on molecular and virologic mechanisms underlying the clinical phenotypes of different HBV genotypes are urgently needed.

Complete genome sequence and phylogenetic analysis of hepatitis B virus isolated from Turkish patients with chronic HBV infection

Hepatitis viruses are the leading causes of chronic liver disease resulting in chronic hepatitis, cirrhosis, and hepatocellular carcinoma in the world and also in Turkey. Although Turkey has an intermediate rate of hepatitis B virus (HBV) infection with a prevalence reported as 5%, a complete HBV genome sequence has not been published. In this study, the molecular characterization and phylogenetic analysis are described of 11 complete HBV genomes isolated from 11 naïve patients (5 male, 6 female; ages: 18--54 years old, median 35 years old) with chronic HBV infection. Of 11 patients, 7 and 4 were HBeAg positive/anti-HBe negative and HBeAg negative/anti-HBe positive, respectively. All patients had no co-infection with HCV, HDV, or HIV. HBV DNA was extracted from the sera of the patients. The complete genome was amplified by PCR and cloned into a TA vector. The PCR products were sequenced directly and the complete HBV genome sequences were determined. Ten HBV genomes were 3182 base pairs in length. There was a 183 bp deletion (between nucleotides 2987--3169) in pre-S region in one HBeAg positive patient. There were two pre-core stop codons (G1896A) in two HBeAg negative and three core promoter dual mutations (T1762/A1764) in one HBeAg positive and two HBeAg negative patients' HBV genomes. Phylogenetic analysis of all complete genomes yielded that all Turkish sequences were clustered in genotype D branch (ten in subgenotype D1 and one in subgenotype D2). The analysis of S gene amino acid sequences revealed that surface gene subtypes of one and ten HBV strains were subtype ayw3 and ayw2, respectively. This study indicates that Turkish patients with chronic hepatitis B infection show very little genotypic heterogeneity. Genotype D of HBV DNA and subtype ayw2 of surface gene represent almost the whole Turkish patient population infected with HBV.

Current treatment and future directions in the management of chronic hepatitis B viral infection

The World Health Organization places hepatitis B virus (HBV) in the top 10 causes of death worldwide. It is estimated that there are over 400 million carriers of HBV as well. At least 20% to 30% of hepatitis B surface antigen (HBsAg) carriers will die of complications of chronic liver disease, including cirrhosis and liver cancer. The serious consequences of end-stage liver disease and liver cancer occur in 30% of chronic carriers and confront patients and physicians throughout the world. Vaccination is the major form of treatment (prevention) that may eventually eliminate HBV worldwide. This article discusses the currently available treatments as well as evolving treatments for chronic HBV infection.

Geographic distribution, virologic and clinical characteristics of hepatitis B virus genotypes in China

The significance of hepatitis B virus (HBV) genotypes for the heterogeneity of chronic HBV infection and severity of liver disease is not well understood. The aim of this study was to determine the distribution and virologic characteristics of HBV genotypes in China and possible association with the diversity of liver disease. The study includes 1096 chronic HBV carriers from nine provinces in China. We collected clinical and laboratory data and analysed the HBV strains in sera by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and nucleotide sequencing techniques. The most common HBV genotypes were B (41%) and C (53%), while genotypes A and D were also found. A North-South divide was identified in genotype B and C distribution - genotype C was predominant in northern China, while genotype B was more prevalent in southern provinces. Patients with genotype B were younger than those with genotype C, and had a lower prevalence of HBeAg - 65%vs 72%, respectively (P = 0.03). However, the severity of liver disease did not differ significantly between patients infected with genotype B or C - neither when comparing liver function tests (1024 patients), nor hepatic inflammation and fibrosis (264 patients). Amongst 47 patients with genotype D (by PCR-RFLP), 37 (79%) were infected with a new subtype (designated Dc), having a recombination fragment from genotype C precore/core region. This is the first large-scale HBV genotype study from China and convincing documentation of the North-to-South gradient of genotypes C vs B in this country. HBV DNA recombination over the surface and precore/core genes increases the diversity of HBV strains and may have diagnostic and clinical implications.

Hepatitis B virus genotypes and extrahepatic manifestations

BACKGROUND/AIMS

This study aimed at correlating the presence of extrahepatic manifestations with hepatitis B virus (HBV) genotypes in patients with chronic HBV infection.

METHODS

This was a national (France), multicenter, retrospective, cross-sectional study. HBV genotypes were determined in 190 patients HBsAg-positive for at least 6 months and documented before any treatment.

RESULTS

Patients were aged 42+/-15 years and mainly male (77%). Alcohol intake was high in 6% of them, ALT elevated in 73%; 27% were cirrhotic. All HBV genotypes were found, mainly A (24%), D (29%), C (11%), and E (10%). Thirty (16%) patients had clinical extrahepatic manifestations, mainly sensory-motor deficiency, sicca syndrome, myalgia, glomerulonephritis, and arthralgia-arthritis. Their presence was not related to any epidemiologic, viral (including genotypes) or hepatic factor, but to a higher platelet count (P=0.004). Twenty-nine (15%) patients had biological extrahepatic manifestations, mainly anti-smooth muscle, antinuclear, and anti-nucleosome antibodies. Their presence was related only to anti-HBe antibodies positivity (P=0.007) or elevated platelet count (P=0.003). Carrying precore mutant HBV increased by 2.8 folds the risk to have at least one extrahepatic biological manifestation.

CONCLUSIONS

No relationships between HBV genotypes and the presence of extrahepatic manifestations were evidenced in patients with chronic HBV infection.

Application of hepatitis B virus genotyping and phylogenetic analysis in intrafamilial transmission of hepatitis B virus

BACKGROUND

Infection with hepatitis B virus (HBV) in early life frequently results in persistent infection, and clustering of the chronic infection within a family is common. However, the relative contribution of perinatal mother-to-infant transmission or early horizontal transmission to the intrafamilial clustering of HBV infection remains unclear. Therefore, we used HBV genotyping and phylogenetic analysis to elucidate the modes of intrafamilial HBV transmission in Taiwan.

METHODS

HBV genotypes and serological markers were determined for 103 individuals from 20 families with evidence of clustering HBV infection.

RESULTS

Three patterns of intrafamilial clustering of HBV infection were identified. Among the 20 families, 8 included a hepatitis B surface antigen (HBsAg)-positive mother (pattern I), 7 included an HBsAg-positive father (pattern II), and in the remaining 5, both parents were positive for HBsAg (pattern III). The rates of HBsAg positivity for children of the 3 representative groups of families were 85.7%, 65.4%, and 87.5%, respectively (P = .16). The identical genotyping results between index parent and carrier children indicated that pattern I clustering was caused by maternal transmission, whereas pattern II clustering was caused by paternal transmission. In pattern III clustering, a concordant HBV genotype between carrier children and mother or father was found in 3 and 2 families, respectively. The modes of transmission were confirmed by phylogenetic analysis in 1 family of each pattern.

CONCLUSIONS

In Taiwan, maternal and paternal transmissions are both important in the intrafamilial spread of HBV infection.

Long-term results of lamivudine monotherapy in Korean patients with HBeAg-positive chronic hepatitis B: response and relapse rates, and factors related to durability of HBeAg seroconversion

OBJECTIVE

The aim of this study was to evaluate retrospectively the long-term effects of lamivudine in 461 Korean patients with chronic hepatitis B who were treated for more than 12 months.

METHODS

The annual rates of virological response and breakthrough were examined and the predictive factors for post-treatment relapse in 114 patients who achieved hepatitis B e antigen (HBeAg) loss or seroconversion after lamivudine therapy were also analyzed.

RESULTS

During follow-up, the rates of HBeAg seroconversion after 1, 2, 3, 4 and 5 years of treatment were 22.9, 33.2, 47.6, 54.2 and 58.8%, respectively, while those for virological breakthrough at 1, 2, 3 and 4 years were 8.2, 41.7, 55.7 and 64.8%, respectively. Ninety-five patients (20.6%) had HBeAg seroconversion and 19 (4.1%) showed HBeAg loss alone with disappearance of hepatitis B virus DNA in serum. Seroconversion was higher with prolonged treatment in patients who had elevated serum alanine aminotransferase. The cumulative relapse rates in the seroconversion group were 52.0 and 55.7% 1 and 2 years after treatment, respectively. Age and the duration of additional treatment were significant predictive factors for post-treatment relapse. Patients aged </=40 who had additional treatment for >12 months after seroconversion had the lowest relapse rate (p < 0.001).

CONCLUSIONS

These results suggest that additional treatment for over 12 months after HBeAg seroconversion in younger patients may produce a better long-term outcome.

Distribution of genotype/subtype and mutational spectra of the surface gene of hepatitis B virus circulating in Hanoi, Vietnam

In order to ascertain the molecular epidemiological features and mutational spectra of hepatitis B virus (HBV) in Hanoi, Vietnam, direct sequencing of the 219-nucleotide fragment of the surface (S) gene of HBV from the sera of 40 patients mostly with chronic hepatitis were carried out. The samples were classified into genotypes by phylogenetic and genotype-specific analysis, and subtypes by the deduced amino acid sequences. The results showed that genotype B with ayw1 was predominant genotype/subtype (63%), followed by genotype C with adr (18%). The quasi-species nature of the HBV in the sera was observed in 24 of 40 samples examined. One sample (HN109) showed mixture of genotypes B and C. Among 26 amino acid substitutions, 16 were the variants and the remainders were mutations. In the "a" determinant region, three mutations with methionine to leucine (L) changes at the 133 amino acid residue were in the first loop and no mutations were in the second loop. A new mutation, threonine to methionine at 126 amino acid residue, was observed in one sample. In conclusion, the analysis of the S gene region of HBV showed that in Hanoi, genotype B with ayw1 was prevalent and the quasi-species nature of HBV was also common.

High rates of early HBeAg seroconversion and relapse in Indian patients of chronic hepatitis B treated with Lamivudine: results of an open labeled trial

Background

The use of Lamivudine in chronic hepatitis B (CHB) is well known, however the reported rate of HBeAg sero-conversion and its durability post-treatment have varied considerably. We undertook the present study to study the effect of Lamivudine on HBeAg loss and seroconversion rates in Indian patients of CHB in relation to frequency, predictors and durability.

Methods

We treated 60 patients of e antigen positive CHB (with active viral replication and ongoing necro-inflammatory activity) with Lamivudine. They were followed up by monthly aminotransferases, and 3 monthly HBeAg and anti-HBe. Those who attained HBeAg sero-conversion were advised to discontinue Lamivudine after 6 months and followed up every 3 months thereafter, to see for relapse. Treatment was given for maximum of 3 years if not sero-converted.

Results

The annual incremental loss of HBeAg in patients receiving Lamivudine was 25 (41.6%) at end of 1^st year, 33 (55%) at 2^nd year and 35 (58.3%) at 3^rd year. The corresponding rates for full sero-conversion were 17/60 (28.6%), 22/60 (36.6%) and 24/60 (40%) in the 3 years. HBeAg loss correlated with increased pre-therapy ALT levels (p = 0.002) and decreased pretreatment HBV-DNA levels (p = 0.004). The presence of cirrhosis had no influence on the rate of HBeAg loss. Relapse occurred in 35% (7/20) post-treatment at median time of 6 months.

Conclusion

Indian patients showed a higher rate of HBeAg sero-conversion in the first year of Lamivudine treatment. This correlated with baseline ALT and inversely with HBV-DNA levels. Relapse rate after treatment was high and occurred soon after stopping treatment.

Relationship of genotypes of hepatitis B virus to mutations, disease progression and response to antiviral therapy

Phylogenetic analysis has led to the classification of hepatitis B virus into eight genotypes, designated A to H. The genotypes have differences in biological properties and show heterogeneity in their global distribution. These attributes of the genotypes may account not only for differences in the prevalence of hepatitis B virus mutants in various geographic regions, but also be responsible for differences in the clinical outcome and response to antiviral treatment in different population groups.

Hepatitis B virus genotypes in Korea: an endemic area of hepatitis B virus infection

OBJECTIVES

It has been reported that distribution of hepatitis B virus (HBV) genotypes shows geographic difference and are associated with clinical outcomes of HBV infection, including response to antiviral therapy and progression of chronic liver diseases. In this study, we analyzed the distribution of HBV genotypes according to the various clinical outcomes of chronic HBV infection in Korea, which is one of the most endemic areas of HBV infection.

METHODS

A total of 200 patients with chronic HBV infection were enrolled. Clinical diagnoses of the 200 patients with chronic liver diseases were as follows: hepatitis B e antigen (HBeAg)-positive healthy carrier (defined as HBeAg(+), anti-HBe(-), HBV DNA(+) by hybridization, normal transaminase; n = 40); inactive HBsAg carrier (n = 40); chronic hepatitis B (n = 40); liver cirrhosis (n = 40); hepatocellular carcinoma (n = 40). HBV genotypes were determined by nested polymerase chain reaction using genotype-specific primers.

RESULTS

All patients except 2 (inactive HBsAg carriers) were positive for nested PCR and they have genotype C regardless of clinical outcomes.

CONCLUSIONS

HBV genotype was genotype C regardless of various clinical outcomes of chronic HBV infection in Korea. Considering that HBV genotypes have clinical relevance, distribution of HBV genotype in each area should be monitored when management for chronic HBV infection is planned.

Influence of HLA-DRB1 alleles and HBV genotypes on interferon-α therapy for chronic hepatitis B

AIM: To investigate the influence of HLA-DRB₁ alleles and HBV genotypes on interferon-α therapy for chronic hepatitis B.

METHODS: HLA-DRB1*03, *07, *09, *12, *15 alleles were determined using polymerase chain reaction/sequence specific primer (PCR/SSP) technique in 126 patients with chronic hepatitis B and 76 normal control subjects in Shandong Province, and HBV genotypes were determined by nested-PCR analysis using type-specific primers in 126 patients.

RESULTS: The positivity of HLA-DRB1*07 allele in chronic hepatitis B group was significantly higher than that in normal control group (χ² = 6.33, P < 0.025, RR = 2.37). Among the 126 patients, genotype B was found in 38 (30.2%), genotype C in 69 (54.8%), and mixed genotype (B+C) in 19 (15.0%), genotypes D-F were not found. Among the 46 DRB1*07(+) patients, 7 were responders and 39 were non-responders among them (χ² = 6.71, P < 0.05). The positivity of HLA-DRB1*07 and prevalence of HBV genotype C were significantly higher in non-responders than in responders.

CONCLUSION: High positivities of HLA-DRB1 ^*07 allele and HBV genotype C are closely associated with the lower response to interferon-α therapy for chronic hepatitis B.

Chronic Hepatitis B and Viral Genotype: The Clinical Significance of Determining HBV Genotypes

The global health challenge posed by the hepatitis B virus (HBV) centres around the widespread distribution and the serious complications as a result of persistent infection with the virus. As with other chronic diseases mediated by pathogens such as human immunodeficiency virus (HIV) and hepatitis C virus (HCV), clinicians are searching for epidemiological, pathological and viral characteristics of HBV infection that may lead to more effective management of patients with chronic infection. Unlike HCV, the role of HBV genotype in disease progression, severity, response to therapy and drug resistance is still under investigation and just beginning to be clarified. This review examines the potential role of HBV genotype determination in the clinic with emphasis on how this genetic information may used to provide effective management for the treatment of patients with chronic hepatitis B.

Response to long-term lamivudine treatment (up to 5 years) in patients with severe chronic hepatitis B, role of genotype and drug resistance

Lamivudine is effective in suppressing viral replication, normalizing alanine aminotransferase (ALT), and improving histological appearance in HBe positive and negative hepatitis. It is unclear whether hepatitis B virus (HBV) genotype influences the response to lamivudine. We report the long-term response of patients with chronic hepatitis B with and without cirrhosis at baseline treated with lamivudine according to HBV genotype. Retrospective review of charts of all patients treated with lamivudine monotherapy between 1993 and 2002. Response to therapy defined as ALT in the normal range, undetectable HBV DNA, and in the HBeAg positive group loss of HBeAg and/or the development of anti-HBe. HBV DNA measured by the Digene Hybrid capture assay (sensitivity 1.4 x 10(6) copies/mL). YMDD mutation at rtL180M and rtM204V/I measured by restriction digest of amplified products. Genotyping performed by sequencing and phylogenetic tree analysis of the preS region of the virus genome. Seventy-one patients treated with lamivudine for 6 months or more, 53 (75%) were male, average age 47 years, 38 (54%) were HBeAg+ and 33 (46%) HBeAg-. Mean baseline HBV DNA viral titre was 1280.2 copies/mL and 518 copies/mL respectively. Cirrhosis was present in 30 (42%). Sera were examined for YMDD mutations at last patient visit in 61 (86%), and were detected in 45 (74%), there being no association with a particular genotype. Data from up to 5 years on lamivudine indicated no difference in biochemical or virological response between genotypes. Cirrhosis was more prevalent with specific genotypes. We found no influence of HBV genotype on the development of resistance to lamivudine, however liver disease severity was influenced by genotype.

Efficacy of lamivudine re-treatment for relapsed patients after an initial lamivudine therapy in HBeAg-positive chronic hepatitis B

The efficacy of lamivudine re-treatment in chronic hepatitis B (CHB) patients who relapse after HBeAg seroconversion with lamivudine has not been investigated. The aim of this study was to evaluate the efficacy of lamivudine re-treatment in relapsed patients. Among 192 patients who had achieved HBeAg seroconversion with lamivudine at a dose of 100 mg/day, 121 patients discontinued lamivudine. Relapse occurred in 49 patients (40.5%). Thirty-three relapsed patients received lamivudine re-treatment for at least 6 months. The mean duration of lamivudine re-treatment was 16 months and the follow-up period was 8.9 months. HBeAg seroconversion was achieved in 23 patients (69.7%). The cumulative HBeAg seroconversion rates at 5, 9, and 12 months were 60, 64, and 67%, respectively. The mean time to HBeAg seroconversion in lamivudine re-treatment was shorter than that in the initial therapy (4.7 months vs. 9.7 months). Viral breakthrough occurred in six (18.2%) patients. All patients with viral breakthrough were accompanied by elevation of serum alanine aminotransferase (ALT) levels. Among 15 patients who discontinued lamivudine re-treatment after HBeAg seroconversion, relapse occurred in six patients (40%). All relapses occurred within 9 months after the discontinuation of lamivudine re-treatment. In conclusion, lamivudine re-treatment in relapsed patients after initial lamivudine therapy had a higher response rate and shorter duration to HBeAg seroconversion than during the initial therapy. However, HBeAg seroconversion induced by lamivudine re-treatment was not durable.

Basal core-promoter mutant of hepatitis B virus and progression of liver disease in hepatitis B e antigen-negative chronic hepatitis B

BACKGROUND/AIMS

The long-term outcomes in hepatitis B e antigen (HBeAg)-negative chronic hepatitis B are distinct from those in HBeAg-positive chronic hepatitis. However, the molecular virological factors that contribute to the progression of liver disease in this special clinical setting remain largely unknown. We thus investigated the association of hepatitis B virus (HBV) genotypes as well as precore/basal core-promoter mutations with the clinical and virological characteristics of patients with HBeAg-negative chronic hepatitis B in Taiwan.

METHODS

HBV genotypes and sequences of precore and basal core-promoter regions of the HBV genome were determined in 174 HBeAg-negative chronic HBV infection patients including 62 inactive carriers and 112 with different stages of liver disease.

RESULTS

HBV carriers with older age (> 50 years) (odds ratio, 9.09; 95% confidence interval (CI), 3.22-25, P < 0.001) and basal core-promoter mutant of HBV (odds ratio, 4.12; 95% CI, 1.41-12.03, P = 0.01) were associated with the development of liver cirrhosis and hepatocellular carcinoma (HCC). The gender-related risk factors associated with the development of liver cirrhosis and HCC were further analyzed, and basal core-promoter mutant was only associated with the development of liver cirrhosis and HCC in male carriers (odds ratio, 4.35; 95% CI, 1.30-14.52, P = 0.02).

CONCLUSIONS

The risk of development of liver cirrhosis and HCC is significantly increased in patients with advanced age as well as with basal core-promoter mutant of HBV. In addition, basal core-promoter mutant might contribute to the gender difference of the progression of liver disease in HBeAg-negative chronic hepatitis B in Taiwan.

Asian-Pacific consensus statement on the management of chronic hepatitis B: a 2005 update

BACKGROUND/AIMS

A large amount of new data on the treatment of chronic hepatitis B has become available such that the 2003 consensus statement requires revision and update.

METHODS

New data were presented, discussed and debated in an expert pre-meeting to draft a revision. The revised contents were finalized after discussion in a general meeting of APASL.

RESULTS

Conceptual background, including the efficacy and safety profile of currently available and emerging drugs, was reviewed. Nineteen recommendations were formed and unresolved issues and areas for further study were suggested.

CONCLUSION

The current therapy of chronic hepatitis B is modestly effective but not satisfactory. The development of new drugs and new strategies is required to further improve the outcomes of treatment.