Hepatitis B e antigen-negative chronic hepatitis B in Hong Kong

Use of hepatitis B virus DNA quantitation to predict hepatitis B e antigen reversion in cases of chronic hepatitis B

Seventy-three chronic hepatitis B patients who had either hepatitis B e antigen (HBeAg) seroconversion (group I) or HBeAg-negative disease (group II) were studied. HBV DNA levels at HBeAg seroconversion (group I) and at initial visits (group II) were significantly lower among patients who were persistently negative for HBeAg than among those who underwent HBeAg reversion.

Characteristics of core promoter and precore stop codon mutants of hepatitis B virus in Vietnam

In Asia, genotypes B and C are the most common genotypes of hepatitis B virus (HBV); and genotype C causes more severe liver disease. Core promoter/precore (CP/PC) mutants, known to be linked to these genotypes, could have an impact on the progression and severity of liver disease. Sera of 115 patients, including 39 acute and 76 chronic Vietnamese HBV infected patients, were tested for their liver profile, HBeAg, HBV genotypes, and HBV DNA level. Fragments of 282 nucleotides covering CP/PC were amplified, sequenced, and analysed. In the acute group, CP/PC mutants accounted for 38.4 and 25.6%, respectively. Genotype B was found to be predominant (74.3%, P < 0.05) and linked to the PC mutant (A1896) (P < 0.05). In the chronic group, CP/PC mutants accounted for 61.7 and 32.8%. CP mutants, especially the T1762/A1764 double mutant, were found to correlate with genotype C (81%, P < 0.001), liver cirrhosis, and hepatocellular carcinoma (P < 0.05). Therefore, genotype C in Vietnam, which carried high rate of C-1858 (70%), could play an important role in causing severe chronic liver disease.

Viral hepatitis B

More than 400 million people worldwide are chronically infected by the hepatitis B virus. The virus is responsible for more than 300000 cases of liver cancer every year and for similar numbers of gastrointestinal haemorrhage and ascites. Major breakthroughs have been achieved in diagnosis and treatment of this virus. Hepatitis B vaccine reduces incidence of liver cancer. As with hepatitis C, advances have been made in molecular virology, especially for naturally occurring and treatment-induced mutant viruses. The clinical significance of low viral load and genotypes are also under investigation. Currently available monotherapies-interferon, lamivudine, and adefovir dipivoxil-very rarely eradicate the virus, but greatly reduce its replication, necroinflammatory histological activity, and progression of fibrosis. Lamivudine, and presumably other nucleoside analogues, can reverse cirrhosis of the liver.

Hepatitis B virus genotype has no impact on hepatitis B e antigen seroconversion after lamivudine treatment

AIM: To investigate the association of hepatitis B virus (HBV) genotype and HBeAg seroconversion after nucleotide analogue treatment.

METHODS: Chronic hepatitis B patients receiving lamivudine followed up for at least 6 months post-treatment were studied. Consecutive treatment-naïve patients who were prospectively followed up in the clinic for at least 18 months were studied as controls. HBeAg seroconversion was defined as loss of HBeAg, appearance of anti-HBe and normalization of alanine aminotransferase for at least 6 months.

RESULTS: Thirty-five patients on lamivudine and 96 control patients followed up for 39 (18-49) months were studied. Lamivudine was given for 12 (10-18) months, and patients were followed up for 15 (6-34) months after drug cessation. Genotype B and C HBV were found in 43 and 88 patients and HBeAg seroconversion occurred in 12 (28%) and 16 (18%) patients, respectively (P = 0.30). There was no difference in HBeAg seroconversion between patients infected by genotype B and C HBV in the control (35% vs 21%, P = 0.25) and lamivudine-treated (14% vs 10%, P = 1.00) groups.

CONCLUSION: HBeAg seroconversion after treatment by lamivudine was not influenced by the HBV genotype.

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Use of prophylactic lamivudine and mycophenolate mofetil in renal transplant recipients with chronic hepatitis B infection

Chronic HBsAg carriers are known to have a higher risk of hepatitis-related mortality and morbidity when undergoing kidney transplantation. Immunosuppressants might flare up the infection that could be fulminating. Lamivudine and mycophenolate mofetil (MMF) have been shown to be effective in inhibiting replication of hepatitis B virus (HBV). With these two drugs, hepatitis related adverse outcome might be preventable when these patients are being transplanted. Four Chinese adolescents with chronic HBV infection were transplanted in our Department from 1999 to 2001. Immunosuppresants included prednisolone, cyclosporin A and MMF; azathioprine was not used for its potentially liver toxic effect. Prophylactic lamivudine 3 mg/kg and maximum 100 mg daily was given just before transplantation and was continued afterwards. HBV status and liver enzymes were monitored serially. Patients were followed up for 26.0 +/- 10.3 (11-34) months post-transplant and no mortality was reported. All grafts were functioning and no rejection was noted. MMF and lamivudine were well tolerated. Alanine transaminase was only transiently elevated in the first 2 months post-transplant in all patients and became normal afterwards. The patients were clinically well and liver function was normal at the last follow-up. However, HBV DNA became positive in three patients after the transplantation. YMDD mutant HBV was negative in one patient and undeterminable in the other three due to low virus load. In summary, with prophylactic lamivudine and MMF, short-term follow-up showed that renal transplant might be feasible and safe in chronic HBV carriers.

Habitual betel quid chewing as a risk factor for cirrhosis: a case-control study

Betel quid chewing, part of traditional Taiwanese culture, is common in 10%-20% of the human population worldwide. In this case-control study we assessed the independent and interactive role of habitual betel quid chewing and chronic hepatitis B virus (HBV) and hepatitis C virus (HCV) infection on risk of cirrhosis. Subjects enrolled included 210 pairs of sex- and age-matched cirrhotic patients and healthy controls. Information on risk factors was obtained through serologic examination of hepatitis B surface antigen (HBsAg) and antibodies to hepatitis C virus (anti-HCV), and a standardized personal interview with a structured questionnaire. Univariate analysis indicated that betel quid chewing, HBsAg+, anti-HCV+, alcohol drinking, and smoking are significant risk factors for cirrhosis. Multivariate analysis indicated that betel quid chewing (odds ratio [OR], 3.56), HBsAg (OR 20.37), and anti-HCV (OR 31.43) are independent risk factors for cirrhosis. Most betel quid chewers habitually drink alcohol. Although our analysis indicates that betel quid chewing acts independently from alcohol as a risk factor for cirrhosis, the confounding effect of alcohol cannot be excluded entirely by our study. There was an additive effect of the interaction between betel quid chewing and the presence of either HBsAg or anti-HCV. Moreover, a higher risk of cirrhosis was associated with longer duration of betel quid chewing and greater amount of betel quid consumed (each p for trend <0.0001). In conclusion, betel quid chewing appears to be an independent risk factor for cirrhosis. There is an additive interaction between betel quid chewing and chronic HBV/HCV infection.

Prevalence of HBV precore/core promoter variants in the United States

Variants in the precore (G(1896)A) and core promoter (A(1762)T, G(1764)A) regions of hepatitis B virus (HBV) may be related to serum HBV DNA levels and severity of liver disease. The aims of this nationwide study were to determine the prevalence of HBV precore/core promoter variants in the United States and the association between these variants and patient demographics, HBV genotypes, serum HBV DNA level, and severity of liver disease. A total of 694 consecutive chronic HBV-infected patients seen in 17 U.S. liver centers during a 1-year period were enrolled. Demographic, clinical, and laboratory data were collected. Sera were tested for HBV genotypes as well as precore and core promoter variants by line-probe assays. Quantitative HBV DNA levels were determined using Cobas Amplicor HBV Monitor kits. Precore and core promoter variants were found in 27% and 44% of patients with chronic HBV infection in the United States. Precore and core promoter variants were more common in hepatitis B e antigen (HBeAg)-negative than in HBeAg-positive patients (precore, 38% vs. 9%; core promoter, 51% vs. 36%; respectively, P <.001). The prevalence of these variants was related to ethnicity, place of birth, and HBV genotypes. Patients with core promoter variants were more likely to have hepatic decompensation. Precore and/or core promoter variants were associated with higher serum HBV DNA levels in HBeAg-negative but not in HBeAg-positive patients. In conclusion, HBV precore and core promoter variants are not rare in the United States. Physicians should be aware of the existence of HBV precore and core promoter variants and the clinical condition of "HBeAg-negative chronic hepatitis."

Mutations within the hepatitis B virus genome among chronic hepatitis B patients with hepatocellular carcinoma

Chronic hepatitis B infection is a major cause of hepatocellular cancer (HCC). The pathogenesis of the carcinogenesis is not fully understood. Viral proteins such as the X protein and the truncated middle S protein have been implicated to be transactivators. In order to investigate whether any mutations within relevant parts of the hepatitis B virus (HBV) genome could be associated with the development of HCC, the genomes of 16 HBV strains from chronic HBV carriers with HCC were studied. Serum samples were subjected to PCR and the HBV DNA sequenced subsequently. Genotypes A-D were represented. The sequence analysis showed that an especially high proportion, 50% (CI 95%, 25-75%), of the patients with HCC carried HBV mutants with deletions or insertions in the N-terminal half of the pre-S2 region or had a point mutation in the start codon of pre-S2 compared with controls with chronic HBV infection, 21% (CI 95%, 3-39%). A high proportion (69%) also had mutations at position 1762 (A --> T) and/or 1764 (G --> A) in the core promoter region, but the proportion of core promoter mutations was no different from what was found in a control group of HBV carriers without HCC (68%). The pre-S2 variants, which involve deletions of immunogenic regions, may have a survival advantage as they are mostly found in long-standing HBV infection. There were no other mutations found frequently within the region coding for the X protein.

Hepatitis B virus genotypes in the United States: results of a nationwide study

BACKGROUND & AIMS

Hepatitis B virus (HBV) genotypes may be related to severity of liver disease and treatment response. The aims of this nationwide study were to determine the prevalence of HBV genotypes in the United States and the association between HBV genotypes and patient demographics, mode of infection, and clinical status.

METHODS

A total of 694 consecutive chronic HBV-infected patients seen in 17 U.S. liver centers during a 1-year period were enrolled. Demographic, clinical, and laboratory data were collected. Sera were tested for HBV genotyping, precore, and core promoter variants by line-probe assays.

RESULTS

All 7 HBV genotypes (A-G) were found, with genotypes A and C the most common. The prevalence of HBV genotypes was different in different regions of the United States. A strong correlation was found between HBV genotypes and ethnicity. HBV genotype A was prevalent among white and black patients, whereas genotypes B and C were most common among Asian patients. The predominant genotype among patients born in the United States, Europe, the Far East, and Southeast Asia were A, D, C, and B, respectively. Genotypes A and C were associated with a higher prevalence of hepatitis B e antigen. Precore variant was detected in 27% of patients and core promoter variant in 44% of patients.

CONCLUSIONS

Our study suggests that the epidemiology of HBV infection in the United States may have changed over time as a result of immigration from countries with a high prevalence of HBV infection. HBV genotypes may account for the heterogeneity in disease manifestations among patients with chronic HBV infection.

Rapid and sensitive assays for determination of hepatitis B virus (HBV) genotypes and detection of HBV precore and core promoter variants

Hepatitis B virus (HBV) genotypes may influence HBeAg seroconversion rates, mutational patterns in the precore (PC) and core promoter (CP) regions, severity of liver disease, and response to antiviral treatment. Development of rapid, simple, and standardized assays to detect viral genotypes and common mutations in the PC and CP regions can accelerate research on the clinical significance of these variants. We aim to assess the accuracy of a line probe assay in determining HBV genotypes and detecting HBV PC and CP variants. HBV genotypes in 701 patients and PC and CP variants in 600 patients with chronic HBV infection from China and the United States were studied using the INNO-LiPA assay. All but one (99.9%) sample were classified by the genotyping assay. All eight genotypes, i.e., A to H, were found. The INNO-LiPA genotyping assay results were completely concordant with those of sequencing. Using the INNO-LiPA PC assay, 99.8 and 94.7% samples were classifiable in the PC and CP regions, respectively. The PC assay results were completely concordant with those of sequencing in all samples that showed either wild-type or variant sequence. The line probe assay was more sensitive in detecting mixtures than was direct sequencing. By INNO-LiPA, only 50 and 27% of the samples, with mixed wild-type and variant sequence in the PC and CP region, respectively, showed mixed sequence by direct sequencing. INNO-LiPA is rapid, sensitive, and reliable-thus enabling accurate determination of HBV genotypes and detection of PC and CP variants in a large population of patients.

A case-control study for early prediction of hepatitis B e antigen seroconversion by hepatitis B virus DNA levels and mutations in the precore region and core promoter

Factors influencing and predictive of seroconversion from hepatitis B e antigen (HBeAg) to antibody (anti-HBe) were sought in a case-control study of 61 patients with chronic hepatitis B who had been observed from 5 years before to 1 year after seroconversion, and 32 patients who did not seroconvert during the entire 6-year period. Almost all of the patients (96%) were infected with HBV genotype C. HBV DNA levels began to decrease 3 years before seroconversion in the seroconverters, while they remained high in the non-converters. The frequency of precore mutation and the loss of HBeAg (A1896) started to increase 1 year before in the converters, and became significantly higher at seroconversion (23 vs. 3%, P = 0.030) than that in the non-converters. Double mutation in the core promoter (T1762/A1764) was more common in the seroconverters than in the non-converters 5 years before seroconversion (48 vs. 28%), and became significantly more frequent at seroconversion (65 vs. 41%, P = 0.046). Seroconversion occurred in 75% of the patients with at least HBV DNA levels <5.5 logarithmic equivalents/mL; precore mutation in 20% or more of HBV DNA; or core promoter mutation. Seroconversion occurred in 50% of those patients within 1 year, 88% within 2 years, and 93% within 5 years. These results indicate that a decrease in HBV DNA levels and mutations in the precore region and the core promoter were associated significantly and complementarily with seroconversion, and each of them or a combination thereof was predictive of seroconversion years ahead.

Natural history of hepatitis B and outcomes after liver transplantation

HBV infection is the single most common cause of cirrhosis globally although the prevalence rate is influenced by geographic region. The natural course of HBV infection and the clinical outcome is dependent on the interplay between host, virus, and environmental factors. Understanding the natural history of HBV infection is important in determining treatment strategies. OLT is the ultimate cure for patients with HBV-related liver failure or HCC. The use of HBIG and new antiviral agents has resulted in significant decrease in HBV re-infection rate and survival of patients transplanted for hepatitis B in recent years is comparable to that of patients transplanted for other liver disease.

Analysis of clinical, biochemical and viral factors associated with early relapse after lamivudine treatment for hepatitis B e antigen-negative chronic hepatitis B patients in Taiwan

The efficacy of lamivudine for HBeAg-negative chronic hepatitis B (CHB) Chinese patients has not been fully investigated. The role of the Hepatitis B virus (HBV) genotype on the treatment effect of lamivudine is controversial. Thirty-two consecutive patients with HBeAg-negative CHB were enrolled. All patients were treated with lamivudine 100 mg once daily of 7-12 months duration. The mean total period of follow-up since entry for all patients was 24 +/- 3.5 months. HBV genotypes were classified by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and verified by sequencing. Precore (G1896A) and basic core promoter (BCP, A1762T & G1764A) mutations were determined by PCR and direct sequencing. Twenty-one (65.6%) patients were infected by genotype B and, 11 (34.4%) by genotype C. G1896A was predominant in genotype B infected patients (95.2%vs 63.6%, P = 0.037). At the end of treatment, 31 (96.8%) and 14 (43.8%) patients achieved biochemical and virological responses, respectively. The biochemical and virological response rates were 40.6 and 0% at 12 months after treatment. Eighteen (56.3%) patients had biochemical relapse within 12 months after withdrawal of lamivudine. By multivariate analysis, the pretreatment serum level of HBV DNA >/=12 Meq/mL was the only factor associated with early biochemical relapse (Odds ratio = 9.333, 95% CI = 1.497 approximately 58.197, P = 0.017). In conclusion, the virological effect of lamivudine for HBeAg-negative CHB is transient. Most patients had biochemical relapse within 12 months after lamivudine treatment regardless of HBV genotype. A high pretreatment viral load is the determinant for early biochemical relapse.

Hepatitis B virus genotypes and virologic response in 694 patients in phase III studies of adefovir dipivoxil1

BACKGROUND & AIMS

Hepatitis B virus (HBV) genotype may influence disease progression and antiviral response. We therefore analyzed the frequency and distribution of genotypes in patients from 2 multinational phase III studies of adefovir dipivoxil. Antiviral efficacy of adefovir dipivoxil 10-mg therapy was examined with respect to HBV genotype, hepatitis B e antigen (HBeAg) serostatus, and race.

METHODS

HBV genotypes were assigned by phylogenetic analyses of DNA sequences amplified from baseline serum samples (n = 694).

RESULTS

Patients from Asia/Oceania were infected predominantly with genotypes B and C, whereas patients from Western European countries were infected predominantly with genotypes A and D. In Mediterranean countries, genotype D was dominant. The most common genotype in North America was C, followed by A, B, and D. Regardless of location, Asian patients were infected predominantly with genotypes B or C, whereas Caucasian patients were infected predominantly with A or D. There were significant differences in the baseline serum HBV-DNA levels of patients infected with different HBV genotypes regardless of HBeAg serostatus. Forty-eight weeks of adefovir dipivoxil 10-mg therapy resulted in potent reductions in serum HBV DNA with no significant differences based on genotype, HBeAg status, or race; similarly, there was no statistical difference in HBeAg seroconversion rates between genotypes in these patients.

CONCLUSIONS

HBV genotypes were distributed asymmetrically with respect to race, geography, and HBeAg status. Forty-eight weeks of adefovir dipivoxil therapy resulted in significant decreases in serum HBV-DNA levels in patients regardless of HBV genotype, HBeAg status, or race.

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

One hundred forty-six hepatitis B e antigen (HBeAg)-positive chronic hepatitis B patients were followed up for 32 +/- 13 months. All six patients with hepatocellular carcinoma had hepatitis B virus (HBV) genotype C. Disease activity was greater in patients infected by HBV genotype C than in those infected by HBV genotype B in the HBeAg-positive phase but not after HBeAg seroconversion.

A large population study of spontaneous HBeAg seroconversion and acute exacerbation of chronic hepatitis B infection: implications for antiviral therapy

BACKGROUND AND AIM

Clinical data on spontaneous hepatitis B e antigen (HBeAg) seroconversion and acute exacerbation of chronic hepatitis B (CHB) virus infection from large population studies are lacking. In the present study we examined the clinical features and significance of HBeAg seroconversion and acute exacerbation in 3063 Chinese CHB patients.

METHODS

Clinical assessment, liver biochemistry, hepatitis B virus (HBV) serology and HBV DNA, time of HBeAg seroconversion, and acute exacerbation were monitored.

RESULTS

Median age at HBeAg seroconversion was 34.5 years. The cumulative HBeAg seroconversion rate significantly increased with alanine aminotransferase (ALT) levels on presentation (p<0.0001). For patients with ALT levels more than twice the upper limit of normal (ULN) on presentation, the HBeAg seroconversion rate at the fifth year of follow up was 72.4%. After HBeAg seroconversion, 65.2% (73/110) of patients had undetectable HBV DNA levels by the Digene Hybrid Capture assay. Of these, 78.1% still had HBV DNA levels detectable by the Amplicor HBV Monitor Test. We found that 37.5% antibody to HBeAg (anti-HBe) positive patients had undetectable HBV DNA levels by the Digene Hybrid Capture assay before acute exacerbation. Acute exacerbations of longer duration, with higher peak ALT, bilirubin, and alpha fetoprotein levels were associated with an increased HBeAg seroconversion rate (p<0.0001-0.045). Acute exacerbation with peak ALT levels more than five times the ULN carried a 46.4% chance of HBeAg seroconversion within three months. HBeAg seroreversion and mortality occurred in 2.7% and 0.7% of acute exacerbations, respectively.

CONCLUSION

In the present study we have provided information on HBeAg seroconversion and acute exacerbation, which are important in decision making for CHB treatment and in designing clinical trials.

Influence of hepatitis B virus genotypes on the progression of chronic type B liver disease

To investigate the hepatitis B virus (HBV) genotype-related differences in the progression of liver disease, 585 patients with chronic HBV infection including 258 with histologically verified chronic liver disease (CLD) and 74 with hepatocellular carcinoma (HCC) were examined. The mean ages of both patients with advanced fibrosis (F3 or F4) and with HCC were significantly older in genotype B than in genotype C patients (P =.018, P =.024, respectively). Both the hepatitis B e antigen (HBeAg) negativity rate at biopsy and the cumulative HBe seroconversion rate in patients with CLD were significantly higher in genotype B patients than genotype C patients (P <.01, P =.022, respectively). Multivariate analysis revealed that genotype B, presence of precore mutation, high ALT levels, and severe histologic activity were independent factors for HBe seroconversion. Among all the biopsy-proven CLD patients, the ratio of patients with advanced fibrosis in genotype B was significantly lower than that in genotype C (4/30 vs. 74/224, respectively; P =.034). This difference was more remarkable in younger patients (< or =45 years; 1/25 vs. 47/180, respectively; P =.020), and there was no difference in older patients (>45 years). The distribution of each genotype between CLD and HCC was very similar (B and C: 11.2% and 87.0% vs. 10.8% and 89.2%, respectively). In conclusion, our results suggest that, although the patients with genotype B experience earlier HBe seroconversion, slower progression of liver fibrosis, and slower development of HCC, the life-long risk of progression to advanced fibrosis and development of HCC may not differ among genotypes B- and C-related chronic liver disease.

Precore and core promoter mutations of hepatitis B virus and hepatitis B e antigen-negative chronic hepatitis B in Korea

BACKGROUND/AIMS

The aims of this study were to determine the frequency of precore/core promoter mutations and hepatitis B e antigen (HBeAg)-negative chronic hepatitis B (e-CHB) in Korea.

METHODS

Patients with chronic hepatitis B virus (HBV) infection were tested for HBeAg, anti-HBe, liver profile and HBV-DNA by a branched DNA (bDNA) assay. Serum HBV-DNA was amplified by a polymerase chain reaction and the precore/core promoter sequence was determined.

RESULTS

Among the 413 consecutive HBeAg-negative patients, 19.6% were bDNA-positive. Evidence of liver disease was found in 90.1% of bDNA-positive and 41.7% of bDNA-negative patients. Overall, 17.7% of HBeAg-negative patients had e-CHB. Precore mutation (A1896) was detected in 93.7% of HBeAg-negative bDNA-positive and 93.9% of HBeAg-negative bDNA-negative patients. In 59 HBeAg-positive patients, 78% had wild-type and 22% had a mixture of wild-type and A1896 mutant. Core promoter TA mutation was detected in 89.9% of HBeAg-negative bDNA-positive patients, 89.8% of HBeAg-negative bDNA-negative patients, and 74.6% of HBeAg-positive patients. No correlation was found between the presence of precore/core promoter mutations and HBV-DNA levels or disease severity.

CONCLUSIONS

In Korean patients infected with HBV genotype C, precore mutation occurred almost invariably along with HBeAg seroconversion and core promoter TA mutation was frequent irrespective of viral replication levels or disease severity.

Quantitative serum HBV DNA levels during different stages of chronic hepatitis B infection

The goals of this retrospective study were to determine whether there is a threshold hepatitis B virus (HBV) DNA value associated with spontaneous or antiviral therapy-related hepatitis B e antigen (HBeAg) clearance. We also investigated whether there is an HBV DNA value that can be used for differentiating inactive carriers from patients with HBeAg-negative chronic hepatitis B. HBV DNA levels in sequential serum samples of 165 Chinese patients with different stages of chronic HBV infection were quantified by a polymerase chain reaction (PCR)-based assay. Our results showed that almost all of the patients (89%) who remained HBeAg-positive had HBV DNA levels that were persistently above 10(5) copies/mL. Serum HBV DNA levels decreased by a mean of 3 log(10) in patients with HBeAg loss, but 51% had levels above 10(5) copies/mL at the time HBeAg first became undetectable. Mean serum HBV DNA levels were significantly lower in HBeAg-negative patients. HBV DNA value above 10(5) copies/mL would exclude all inactive carriers, but 45% of patients with HBeAg-negative chronic hepatitis would also be excluded if testing were only performed at presentation and 30% would be excluded if testing were performed on 3 occasions. In conclusion, serum HBV DNA levels decreased significantly in patients with HBeAg loss, but there was no threshold HBV DNA level associated with HBeAg clearance. Given the fluctuating course of HBeAg-negative chronic hepatitis, it is not possible to define a single cutoff HBV DNA value for differentiating inactive carriers from patients with HBeAg-negative chronic hepatitis.

Genotype B hepatitis B virus is associated with severe icteric flare-up of chronic hepatitis B virus infection in Hong Kong

OBJECTIVE

We aimed to investigate the association of viral genotype and the development of icteric flare-up (IF) in chronic hepatitis B virus (HBV) infection.

METHODS

Twenty-one consecutive patients suffering from IF of chronic HBV infection, defined as elevation of ALT over five times the upper limit of normal, together with either bilirubin > 50 IU/L or elevated bilirubin plus PT > 3 s prolonged, were studied. Patients from three stages of HBV-related chronic liver disease were studied as controls: 1) asymptomatic carriers (31 patients), defined as persistent normal ALT for at least 2 yr; 2) active early cirrhosis (49 patients), defined as Child's A liver cirrhosis plus HBV DNA > 106 Eq/ml; and 3) decompensated cirrhosis (31 patients), defined as Child's B or C liver cirrhosis with complications. Restriction fragment length polymorphism was used for genotyping.

RESULTS

Only genotype B and C HBV were identified in our studied cohort. Ninety-one percent of patients suffering from IF were infected by genotype B HBV (p < 0.001 vs asymptomatic carriers, early cirrhosis patients, and decompensated cirrhosis patients). On the contrary, genotype C HBV was the predominant strain at different stages of chronic liver disease; no statistical difference was found on the relative prevalence of genotype B/C HBV among asymptomatic carriers, early cirrhosis patients, and decompensated cirrhosis patients.

CONCLUSIONS

Genotype B HBV is associated with IF among chronic HBV-infected patients in Hong Kong, whereas genotype C HBV is more prevalent at all stages of chronic liver disease. Our findings suggested that the two different HBV genotypes might have different pathogenic mechanisms of liver damage.

Relationship of clinical and virological factors with hepatitis activity in hepatitis B e antigen-negative chronic hepatitis B virus-infected patients

To investigate the factors associated with active disease among hepatitis B surface antigen (HBsAg) positive/hepatitis B e antigen (HBeAg)-negative chronic hepatitis B virus (HBV) infection we studied chronic HBV infected patients who had undetectable HBeAg at the first visit. HBV DNA was determined by the cross-linking assay (NAXCOR) and polymerase chain reaction (PCR). Mutations in the core promoter and precore regions and viral genotypes were studied. Clinical outcome of these patients were followed and categorized as: (i) relapse (ALT > 200 IU/L or three times the previous levels); (ii) active hepatitis (elevated ALT < 200 IU/L with concomitant detectable HBV DNA); or (iii) remission. A total of eighty-five patients were followed up for 5.5 +/- 1.0 years. At first visit, 31 (36.5%) patients had elevated ALT levels, 12 (14.1%) had measurable HBV DNA by the cross-linking assay and 26 (30.6%) by PCR. Sixteen (18.8%) patients had hepatitis relapse, 13 (15.3%) had active hepatitis, and 56 (65.9%) remained in remission. Core promoter and precore stop codon mutants were found in 27 and 12 patients, respectively. Eleven and 20 had genotype B and C HBV, respectively. Initial elevated ALT and detectable HBV DNA were associated with active liver disease. Patient demographics, viral mutants or genotypes failed to predict disease activity. Hence, serum ALT and HBV DNA levels offer the best prediction of natural course of HBeAg-negative chronic HBV infection.

High hepatitis B virus (HBV) DNA viral load as the most important risk factor for HBV reactivation in patients positive for HBV surface antigen undergoing autologous hematopoietic cell transplantation

The risk factors for hepatitis due to hepatitis B virus (HBV) reactivation in patients positive for hepatitis B surface antigen (HBsAg) treated with autologous hematopoietic cell transplantation (HCT) are unknown. We evaluated 137 consecutive patients (23 positive for HBsAg, 37 positive for hepatitis B surface antibody, and 77 negative for HBV) who underwent HCT. Serial serum ALT were measured before transplant and after transplant at 1 to 4 weekly intervals for the first year and then at 2 to 12 weekly intervals thereafter. Before HCT, basic core promoter (T(1762)/A(1764)) and precore (A(1896)) HBV variants were determined in HBsAg-positive and HBV DNA-positive (by polymerase chain reaction assay) patients by direct sequencing and serum HBV DNA quantitation using the Digene Hybrid Capture II assay. Cox proportional hazards analysis was used to assess the association between pretransplantation HBV virologic and host factors and occurrence of hepatitis due to HBV reactivation. After HCT, hepatitis due to HBV reactivation was more common in HBsAg-positive patients than in HBsAg-negative patients (hazard ratio, 33.3; 95% confidence interval [CI], 7.35-142.86; P <.0001). HBsAg-positive patients with detectable serum HBV DNA before HCT (on Digene assay) had a significantly higher risk of hepatitis due to HBV reactivation than HBsAg-positive patients with no detectable serum HBV DNA (adjusted hazard ratio, 9.35; 95% CI, 1.65-52.6; P =.012). Thus, we found that hepatitis due to HBV reactivation is common in HBsAg-positive patients undergoing autologous HCT. A high HBV DNA level (>10(5) copies/mL) was the most important risk factor for HBV reactivation, and its lowering by administration of nucleoside analogues before transplantation should be considered.

Treatment of chronic hepatitis B: case selection and duration of therapy

Hepatitis B viral (HBV) infection is a major health burden in the Asia-Pacific region. The seriousness of chronic hepatitis B (CHB) is often realized at a late stage. The resultant morbidity and mortality from cirrhosis complications is considerable, with a high human cost. The most affected patients are men aged 40 years or older. Two decades ago, the prognosis for the 300 million "Australia antigen"-positive people (people with chronic HBV infection) was gloomy, with no effective intervention. Twenty years on, research and development have changed their outlook. Chronic hepatitis should now be diagnosed early, at the asymptomatic stage. Proper assessment and judicial introduction of therapy can suppress replication of HBV and resolve liver inflammation, thereby preventing the silent progression of chronic liver disease to end-stage cirrhosis. Interferon (IFN) monotherapy has been available for nearly 20 years, but various limitations restrict its general application. Injection-based therapies are inconvenient, the response rate is low (33% hepatitis B e antigen (HBeAg) seroconversion rate among optimal cases), side-effects are many, and some serious, and the cost is unaffordable for most people. However, in non-cirrhotic patients with mild to moderate disease activity, IFN is still a worthwhile option because the treatment course is shorter, mutation seems less of a problem and most responses are permanent and reduce or abolish late complications. Lamivudine, an oral nucleoside analog with potent antiviral effects, has been approved in many countries. Daily dosing of 100 mg reduces serum HBV-DNA to below detectable levels within 6 weeks. In HBeAg-positive patients, approximately 16% of treated patients seroconverted with the first year. This was associated with significant improvement in liver histology. Long-term treatment induces further HBeAg seroconversion, but overall clinical benefit is undermined by continuous emergence of drug-resistant YMDD mutants. In an Asian multicentre study, 58 patients on 5 years lamivudine therapy showed annual cumulative HBeAg seroconversion rates at 1, 2, 3, 4 and 5 years of 22, 29, 40, 47 and 50%, respectively. The best predictor of response is pretreatment alanine aminotransferase (ALT). Among patients with ALT > 2x the upper limit of normal (ULN), annual HBeAg seroconversion is increased to 38, 42, 65, 73 and 77%, respectively. However, emergence of YMDD mutants occurred at a cumulative rate of 15, 38, 55, 67 and 69%, respectively. The impact of this emergence on disease activity is unpredictable. Thus, while continued disease suppression, or even HBeAg seroconversion, still occurred in some patients, in others hepatitis may relapse and liver failure has been reported despite continuation of lamivudine. While the duration of lamivudine therapy is difficult to define, the best strategy may be to define only active CHB with major ALT elevation (par-ticularly ALT > 5x ULN) for a duration of 1 year or less. Lamivudine can be stopped in responders. The response is durable in approximately 80% of responders. Non-responders should be monitored closely for rebound off treatment. Therapy can be re-instituted if ALT is over 5x ULN. Management of patients with YMDD mutants can be challenging, but there is no clear evidence to recommend stopping or continuing lamivudine, or to add other possible effective agents, such as adefovir dipivoxil. More data are required to help draw up guidelines. Hepatitis B e antigen-negative CHB has been less well studied. Both IFN and lamivudine can suppress disease activity, but permanent responses are few. Without a distinct marker as an end-point for response, the duration of treatment is even more difficult to define. Quantitative polymerase chain reaction for low viral levels may give a clue, but definitive studies are required. Monotherapy is clearly not the answer for the majority of CHB patients with active disease. Combination therapy has the theoretical advantage of additional or synergistic efficacy. Preliminary results on IFN and lamivudine are promising and further clinical trials are ongoing. Emtricitabine (FTC), adefovir dipivoxil, entecavir, BL-thymidine (L-dT), DAPD, clevudine (l-FMAU), thymosin, therapeutic vaccines and various herbal medicines are potential candidates. Antiviral action in conjunction with immune modulation may have a better chance of eradicating HBV and its cccDNA in the hepatocytes as the basis for an eventual successful outcome. The key points are: (i) approved therapeutic agents for chronic hepatitis B (CHB) are IFN, lamivudine and thymosin (in a few countries only); (ii) indications for IFN therapy are viremia in compensated CHB patients with moderately raised ALT; (iii) lamivudine has broader therapeutic indications: it is effective in subgroups of CHB patients with compensated or decompensated liver diseases, but generally works better if patients have raised ALT; (iv) lamivudine has a potent suppressive action on HBV replication, including HBeAg-negative variants, but cannot eliminate cccDNA; this is the reason for the relapse of disease after discontinuing treatment, unless HBeAg seroconversion is obtained; (v) successful use of lamivudine aims at HBeAg seroconversion or profound suppression of HBV-DNA to serum levels of less than 100 000 viral copies/mL, in order to prevent emergence of drug-resistant YMDD mutants (which commences from 6 months onward); (vi) YMDD mutants may cause a flare of hepatitis, resulting in deterioration of liver histology and, occasionally, liver failure; (vii) combination therapy of lamivudine with IFN (standard or pegylated) or other nucleoside analogs should be the next advance. Preliminary data from IFN and lamivudine combination therapy show some promise, but there are conflicting results.

Viral genotype and hepatitis B virus DNA levels are correlated with histological liver damage in HBeAg-negative chronic hepatitis B virus infection

OBJECTIVES

We aimed to study the relationship between the hepatitis B virus (HBV) genotypes, core promoter/precore stop codon mutations, and histological liver damage among hepatitis B e antigen (HBeAg)-negative patients.

METHODS

Liver biopsy specimens of 55 HBeAg-negative chronic HBV-infected patients were studied. A histological activity index was scored for degree of necroinflammation (HAI-NI) and fibrosis (HAI-F) as described by Knodell et al. HBV DNA was determined by a cross-linking assay and polymerase chain reaction (PCR) at the core promoter/precore region and the S region. PCR-positive samples were directly sequenced for core promoter and precore mutations and examined by restriction fragment length polymorphism for genotyping.

RESULTS

Forty-one males and 14 females at a median age of 43 were studied. HBV DNA was detectable in 32 (58%) and 37 (67%) patients by the cross-linking assay and PCR, respectively, at the time of liver biopsy. The median (range) HAI-NI and HAI-F scores were 5 (1-10) and 2 (0-4), respectively. HBV DNA detectable by either the cross-linking assay or PCR was associated with a higher HAI-NI score. Eleven and 31 patients had genotypes B and C HBV, respectively. Genotype C HBV was associated with higher HAI-NI than genotype B HBV. Core promoter mutations and precore stop codon mutation were detected in 74% and 40% patients, respectively, but they were not associated with higher HAI-NI or HAI-F scores.

CONCLUSIONS

Detectable HBV DNA and genotype C HBV, but not core promoter or precore stop codon mutations, are associated with more severe liver damage in HBeAg-negative patients.

World-wide epidemiology of HBeAg-negative chronic hepatitis B and associated precore and core promoter variants

Hepatitis B is a serious disease that is endemic in many parts of the world. A significant proportion of patients with chronic hepatitis B (CHB) are infected with a variant form of the hepatitis B virus (HBV) which decreases or abolishes the production of hepatitis B e-antigen (HBeAg). The purpose of this literature review is to describe the epidemiology of HBeAg-negative CHB (e-CHB) worldwide. A literature search was conducted to identify studies pertaining to e-CHB and underlying variants (precore and core promoter). Fifty studies were included in our analysis. The median prevalence of e-CHB among patients with chronic HBV infection was 33% in the Mediterranean, 15% in Asia Pacific, and 14% in the USA and Northern Europe. The pre core stop codon variant was detected in a median of 60% (range 0-100%) of HBeAg-negative patients overall, 92% in the Mediterranean, 50% in Asia Pacific and 24% in the USA and Northern Europe. There were very few data on the prevalence of core promoter variants outside Asia where the median prevalence among HBeAg-negative patients was 77%. This literature review revealed that e-CHB is more common than previously suspected and that it is present worldwide with marked variations in the prevalence of associated HBV variants across different geographical regions. Additional research using population based samples of adequate size based on a consensus definition of e-CHB and using standardized HBV DNA assays is needed to better estimate the true prevalence of e-CHB and its associated HBV variants.

Changing scene in hepatitis B serology interpretation

Serological tests have been used in the diagnosis of hepatitis B virus (HBV) infection since the virus was first discovered. Advances in molecular biology and improvements in the understanding of HBV virology have changed the scene of hepatitis B serology interpretation.

Lamivudine and alpha-interferon in combination long term for precore mutant chronic hepatitis B

BACKGROUND/AIMS

Alpha-interferon (alpha-IFN) and lamivudine are the two licensed drugs for patients with chronic hepatitis B, however, their efficacy in precore mutant chronic hepatitis B is limited. The aim of this study was to investigate the efficacy of 1 year alpha-IFN-lamivudine combination therapy for anti-HBe/hepatitis B virus- (HBV)-DNA positive patients.

METHODS

Between 1997 and 1999, 29 consecutive anti-HBe/HBV-DNA positive patients entered this prospective pilot study. Patients received 100mg lamivudine orally daily and alpha-IFN 6 million units (MU) three times weekly for 52 weeks. All patients were followed-up for 12 months after stopping therapy. Primary end points were loss of serum HBV-DNA and alanine transaminase normalization at week 52.

RESULTS

Overall, the end-treatment biochemical and virological response was 93% while the sustained response at week 104 was 14%. HBV-DNA negative patients did not experience a viral breakthrough during treatment; no tyrosine-methionine-aspartate-aspartate amino acid motif of HBV polymerase (YMDD) variant emerged. At week 52, 46% of patients with paired liver biopsies slides available, showed an histological improvement (histological activity index > or =2).

CONCLUSIONS

Combination of lamivudine and interferon for 1 year is followed by high end-treatment virological and biochemical response rates, by improvement of liver histology and by the prevention of the emergence of YMDD mutation; however, the sustained response rate remains low.

Immunopathogenesis of hepatitis B e antigen negative chronic hepatitis B infection

Hepatitis B e antigen (HBeAg) negative chronic hepatitis B represents currently the predominant form of chronic hepatitis due to the hepatitis B virus (HBV) in several parts of the world. In this review, recent data regarding the process of HBeAg negative HBV strain selection during the course of chronic HBV infection are presented and the potential virus and/or host-mediated mechanisms that lead to chronic liver necroinflammation, i.e. chronic hepatitis are outlined.

Diagnosis and management of pre-core mutant chronic hepatitis B

Chronic hepatitis due to pre-core hepatitis B virus (HBV) mutants presents as hepatitis B e antigen (HBeAg)-negative chronic hepatitis B (CHB). HBeAg-negative CHB represents a late phase in the natural course of chronic HBV infection that develops after HBeAg loss and seroconversion to anti-HBe. It is usually associated with pre-core stop codon mutation at nucleotide 1896 (mainly selected in non-A HBV genotypes), but also with other pre-core changes or with mutations in the basic core promoter region (mainly in HBV genotype A). In chronic HBV infections, pre-core mutants can be detected both in patients with HBeAg-negative CHB and in inactive hepatitis B surface antigen (HBsAg) carriers. The diagnosis of HBeAg-negative CHB is based on HBsAg positivity, HBeAg negativity, and mainly on increased alanine aminotransferase (ALT) and serum HBV-DNA levels and exclusion of other causes of liver disease. The differential diagnosis between patients with CHB and inactive HBsAg carriers can be made only by close follow-up of aminotransferase activity and viraemia levels, although the cut-off level of serum HBV DNA has not been definitely determined. IgM anti-HBc levels have also been suggested as an index that increases the diagnostic accuracy for transient hepatitis flares, while liver biopsy confirms the diagnosis and evaluates the severity of the liver disease. Interferon-alpha (IFN-alpha) and lamivudine are the two drugs that have been tried, mainly in the management of HBeAg-negative CHB. A 12-month course of IFN-alpha achieves sustained biochemical remission in about 20% of patients, which has been associated with improvement in the long-term outcome of this subset. A 12-month course of lamivudine is rather ineffective, maintaining remission in less than 15% of patients after cessation of therapy. Long-term lamivudine is associated with progressively increasing rate of virological and subsequent biochemical breakthroughs due to YMDD mutants, with approximately 30% of patients remaining in remission in the third year of therapy. Several other antiviral agents are currently being evaluated in this setting with combined regimens being the most reasonable step for the near future.

Risk factors for active liver disease in HBeAg-negative chronic hepatitis B virus-infected patients

OBJECTIVES

HBeAg-negative patients constitute approximately 70% of all chronic hepatitis B virus (HBV) infections in Southeast Asia, and some of these patients continue to suffer from active disease. We aimed to study the risk of hepatitis relapse in chronic HBV-infected patients with negative HBeAg and the predictor(s) of relapses.

METHODS

This was a retrospective analysis of patients carrying HBsAg but lacking HBeAg. Patients recruited were required to have been followed for > or = 12 months with a minimum of three blood samples available for analysis. Patient demographic data, liver biochemistry, and HBV serology were analyzed in relation to relapses of hepatitis. Relapse was defined as an abrupt elevation of ALT > 200 IU/L or > 3-fold previous levels, whichever was higher.

RESULTS

In a period of 3 months, 317 patients seen at the Hepatitis Clinic at the Prince of Wales Hospital in Hong Kong were recruited. The median duration of follow-up was 34 months. On initial consultation, 111 (35.0%) patients had elevated ALT (>60 IU/L). Overall, 57 (18.0%) patients developed at least one relapse, including 37 (33.3%) patients with elevated ALT and 20 (9.7%) patients with normal ALT at the first visit. Multiple logistic regression analysis showed that elevated ALT level at first presentation (odds ratio 4.17, 95% confidence interval 2.24-7.75) and male gender (odds ratio 2.83, 95% confidence interval 1.23-6.49) were the two independent factors associated with a higher risk of hepatitis relapse. The sensitivity, specificity, and positive and negative predictive values of a single ALT test for hepatitis relapse were 64.9%, 71.5%, 33.3%, and 90.3%, respectively.

CONCLUSIONS

HBeAg-negative HBV carriers with normal ALT levels have a low risk of hepatitis relapse.

Evolution of hepatitis B virus polymerase gene mutations in hepatitis B e antigen-negative patients receiving lamivudine therapy

Lamivudine has been shown to be effective in patients with hepatitis B e antigen (HBeAg)-positive chronic hepatitis B, but its long-term efficacy and the rate of resistant mutations in patients with HBeAg-negative chronic hepatitis B is less clear. Twenty-nine patients with HBeAg-negative chronic hepatitis B, who have received lamivudine for at least 1 year were studied to determine the antiviral response, the rate and pattern of lamivudine-resistant mutations, and the effect of lamivudine-resistant mutations on HBeAg status. The mean duration of treatment was 21 +/- 7 months. Before treatment, core promoter variant was detected in 16 (55%) patients and precore stop codon variant in 18 (62%) patients. Serum hepatitis B virus (HBV) DNA was detected by solution hybridization assay in 62%, 4%, and 24% and by polymerase chain reaction (PCR) assay in 100%, 31%, and 40% at months 0, 6, and 24, respectively. The cumulative rates of detection of lamivudine-resistant mutations after 1 and 2 years of treatment were 10% and 56%, respectively. In addition to the duration of treatment, core promoter mutation was associated with the selection of lamivudine-resistant mutants. Three patients with lamivudine-resistant mutations had reversion of the precore stop codon mutation; in 2 patients this was accompanied by the reappearance of HBeAg. We found that lamivudine-resistant mutants were detected at similar rates in patients with HBeAg-negative as in patients with HBeAg-positive chronic hepatitis B. Additional changes in other parts of the HBV genome may restore the replication fitness of lamivudine-resistant mutants.