Identification of a hepatitis B virus S gene mutant in lamivudine-treated patients experiencing HBsAg seroclearance

BACKGROUND & AIMS: Seroclearance of hepatitis B virus (HBV) surface antigen (HBsAg) is a rare event in chronic hepatitis B patients receiving lamivudine therapy. It is generally believed to be a benevolent sign, implicating clearance of viremia. The aim of this study is to examine the authenticity of this dogma. METHODS: In a 5-year period, 11 patients treated with lamivudine experienced seroclearance of HBsAg. The clinical data were examined. The HBV S gene sequences derived from the patient's serum samples before and after seroclearance of HBsAg were analyzed. RESULTS: Serum HBV-DNA could be detected by nested polymerase chain reaction (PCR) in all 11 patients, by 1-step PCR in 8, and by Cobas Amplicor HBV-DNA test (>200 copies/mL) in 5. A mutation hot spot, P120A in the S gene, was identified in 6 of the 11 patients. Site-directed mutagenesis experiments indicated that the Ausria-II RIA test failed to detect this mutant. Decreased sensitivity of detection was also observed when other monoclonal antibodies were applied. CONCLUSIONS: Seroclearance of HBsAg during lamivudine therapy may not indicate viral clearance. Specifically, it may be caused by a point mutation in the S gene, which results in detection failure. In such patients, further verification and follow-up using a sensitive HBV-DNA test are advised.     

Two decades of universal hepatitis B vaccination in taiwan: impact and implication for future strategies

BACKGROUND & AIMS: Following the world's first successful implementation of a universal hepatitis B virus (HBV) vaccination program for infants in Taiwan 20 years ago, we performed this study to evaluate the long-term protection afforded by HBV vaccination and to rationalize further prevention strategies. METHODS: HBV seromarkers, including hepatitis B surface antigen (HBsAg) and antibodies to HBsAg (anti-HBs) and core antigen (anti-HBc), were studied in 18,779 subjects from neonates to adults below 30 years of age in 2004. The birth cohort effect was evaluated by comparing the results of the same birth cohorts at different ages among this survey and the previous 1984, 1989, 1994, and 1999 surveys. RESULTS: The seropositive rates for HBsAg, anti-HBs, and anti-HBc were 1.2%, 50.5%, and 3.7%, respectively, in those born after the vaccination program (<20 years of age) in 2004. A positive maternal HBsAg status was found in 89% of the HBsAg seropositive subjects born after the vaccination program. The absence of an increase in HBsAg seropositive subjects at different ages in the same birth cohorts born after the vaccination program implied no increased risk of persistent HBV infection with aging. CONCLUSIONS: Universal HBV vaccination provides long-term protection up to 20 years, and a universal booster is not indicated for the primary HBV vaccinees before adulthood. Maternal transmission is the primary reason for vaccine failure and is the challenge that needs to be addressed in future vaccination programs. This may include an appropriate hepatitis B immunoglobulin administration strategy for high-risk infants and involve efforts to minimize noncompliance.     

Long-term therapy with adefovir dipivoxil for HBeAg-negative chronic hepatitis B for up to 5 years

BACKGROUND & AIMS: Treatment with adefovir dipivoxil for 48 weeks resulted in clinical improvement in patients with hepatitis B e antigen (HBeAg)-negative chronic hepatitis B that was lost when treatment was discontinued. We investigated the efficacy, safety, and resistance profile of adefovir dipivoxil treatment for up to 240 weeks. METHODS: HBeAg-negative patients were treated double blind with placebo or adefovir dipivoxil 10 mg once daily for 48 weeks, followed by adefovir dipivoxil from week 49 to 96. At week 97, 125 patients enrolled in a 144-week, open-label phase. Patients received adefovir dipivoxil for up to 192 or 240 weeks. RESULTS: Serum hepatitis B virus (HBV) DNA levels were less than 1000 copies per milliliter in 67% of patients, and alanine aminotransferase (ALT) levels normalized in 69% after 240 weeks. After 192 or 240 weeks of treatment, over 83% of patients had improvement in necroinflammation, and over 73% had improvement in fibrosis. Ishak fibrosis scores improved compared with baseline in 35%, 55%, and 71% of patients after 48, 192, and 240 weeks of adefovir dipivoxil, respectively. After 240 weeks, the cumulative probability of HBV polymerase mutations was 29%, but the cumulative probability of mutations with virologic resistance was 20% and of mutations, virologic resistance, and ALT elevations was 11%. Slight elevations in creatinine were confirmed in 4 (3%) patients. CONCLUSIONS: Treatment with adefovir dipivoxil for up to 240 weeks was well tolerated and produced significant, increasing improvement in hepatic fibrosis, durable suppression of HBV replication, normalization of liver enzymes, and delayed development of resistance.     

HBV持续感染及其机制的研究进展

HBV属嗜肝DNA病毒科,可引起人类急性和慢性肝炎,甚至肝硬化、肝癌。目前的抗病毒药物因不能彻底清除肝细胞内HBV,故很难达到治愈的效果。近年来,HBV持续感染的机制受到广泛关注,主要涉及宿主与病毒两方面,从病毒方面展开,主要阐述了cccDNA、HBV颗粒和HBV自身组分维持HBV持续感染的相关研究进展。     

Clinical relevance of hepatitis B virus genotype in children with chronic infection and hepatocellular carcinoma

BACKGROUND & AIMS: The aim of this study was to investigate the influence of hepatitis B virus (HBV) genotypes on the clinical outcome of chronic childhood HBV infection and hepatocellular carcinoma (HCC). METHODS: A total of 460 HBV carrier children were followed-up for 15 years and 26 children with HBV-related HCC were recruited. HBV genotyping was examined at enrollment and the latest follow-up of these carrier children and at diagnosis in HCC children. Viral load was checked at enrollment for the carrier children. These carriers were grouped based on their initial hepatitis B e antigen (HBeAg) and antibody to hepatitis B e antigen (anti-HBe) status. The HBeAg positive (+) group was divided further into an HBeAg(+/+) group and HBeAg(+/-) group, depending on whether spontaneous HBeAg seroconversion occurred during the follow-up period. RESULTS: Genotype B constituted 73%, 86%, and 76% in the HBeAg(+/+), HBeAg(+/-), and anti-HBe(+) groups, respectively. Genotype C was found in 27%, 8%, and 6% in the HBeAg(+/+), HBeAg(+/-), and anti-HBe(+) group, respectively. Genotype C carriers were more prevalent in the HBeAg(+/+) group than the other 2 groups (P = .01), and had a delayed HBeAg seroconversion compared with the genotype B carriers (P < .001). Changes of genotype during the follow-up period were rare (2.8%). In those with HCC, genotype B was also the major type (74%). There was no difference in the baseline viral load between genotypes B and C. CONCLUSIONS: Although HBV genotype B dominates in children with chronic HBV infection and HCC in Taiwan, genotype C delays HBeAg seroconversion in pediatric chronic HBV infection.     

Anti-HBc of IgM-class,HBeAg and anti-HBe in acute and chronic hepatitis B

ABSTRACT— The presence and persistence of IgM antibody against hepatitis B core antigen (anti-HBc IgM) and the correlation with other HBV markers were studied in 42 patients, all of whom had acute HBsAg-positive hepatitis but whose subsequent diseases differed. All patients initially had anti-HBc IgM. In 13 out of 15 patients with uncomplicated acute hepatitis, anti-HBc IgM disappeared within 6 months after onset of the disease. In five out of 12 patients, who in spite of transient HBsAg developed chronic liver disease, the anti-HBc IgM persisted for more than 2 years. Among 15 patients with persistent HBsAg, anti-HBc IgM was present from 7 months to more than 8 years. Seroconversion from HBeAg to anti-HBe was observed in seven patients and in five of these anti-HBc IgM disappeared during the follow-up period. These results indicate that anti-HBc IgM can be used as a serological marker of recent or ongoing HBV infection.     

Long-term safety of lamivudine treatment in patients with chronic hepatitis B

BACKGROUND & AIMS: Data on the long-term safety of lamivudine are limited. The aim of this analysis was to determine the incidence of hepatitis flares, hepatic decompensation, and liver-disease-related (LDR) serious adverse events (SAE) during long-term lamivudine treatment. METHODS: We reviewed data on 998 patients with HBeAg-positive compensated chronic hepatitis B who received lamivudine for up to 6 years (median, 4 years) and 200 patients who received placebo for 1 year. RESULTS: Hepatitis flares occurred in 10% of the lamivudine-treated patients in year 1 and in 18%-21% in years 2-5. A temporal association between hepatitis flares and lamivudine-resistant mutations increased from 43% in year 1 to >80% in year 3. Ten hepatic decompensation events occurred in 8 (<1%) lamivudine-treated patients. Fifty-three (5%) lamivudine-treated patients experienced a total of 60 LDR SAEs. Four patients died, 2 from liver-related causes. The proportion of patients with a documented lamivudine-resistant mutation increased from 23% in year 1 to 65% in year 5. During each year of the study, patients with lamivudine-resistant mutations experienced significantly more hepatitis flares than patients without lamivudine-resistant mutations (P < 0.005). The occurrence of hepatic decompensation (0%-2%) and LDR SAEs (1%-10%) among patients with lamivudine resistance remained stable during the first 4 years with mutations and increased afterward to 6% (P = 0.03) and 20% (P = 0.009), respectively. CONCLUSIONS: This study demonstrated that lamivudine treatment for up to 6 years has an excellent safety profile in patients with HBeAg-positive compensated liver disease, but patients with long-standing lamivudine-resistant mutations may experience worsening liver disease.     

Alteration of the influences of HLA classes I and II alleles on the perinatal hepatitis B virus infection after immunoprophylaxis in Korean children.

Some HLA alleles are known to be associated with hepatitis B virus (HBV) persistence. In order to find out the relationship between HLA and perinatal HBV infection after prophylaxis, we typed HLA classes I and II in 38 HBeAg-positive mothers, their children (19 succeeded and 19 failed in prophylaxis) and 198 HBsAg-negative healthy controls. HLA-B35 (RR=2.8, p<0.03), Cw*07 (RR=2.7, p<0.02), DRB1*07 (RR=3.6, p<0.006), DQA1*02 (RR=3.6, p<0.02) and DQB1*02 (RR=2.4, p<0.05) alleles were higher and DRB1*13 (RR=0.3, p<0.03) and DPB1*0401 (RR=0.1, p<0.01) alleles were lower frequencies in HBeAg-positive mothers than in the control. In failed children to the perinatal HBV prophylaxis, HLA-Cw*0303 allele was significantly higher (p<0.05) and DPB1*0202 allele was lower (p<0.03) than in succeeded children. These results suggest the influences of certain HLA alleles on naturally acquired chronic HBV infection may be changed by perinatal HBV prophylaxis.     

HBsAg-negative hepatitis B virus infections in hepatitis C virus-associated hepatocellular carcinoma

This study was conducted to evaluate reports that hepatitis B virus (HBV) DNA sequences can be found in the serum and/or tumour tissue from some hepatocellular carcinoma (HCC) patients who have no detectable hepatitis B surface antigen (HBsAg) in their sera. Such HBV infections would be highly atypical, because prospective studies have shown a clear succession of specific serologic markers during and after most HBV infections. As most HBsAg-negative HCC patients in Japan have hepatitis C virus (HCV) infections, the present study was conducted to determine whether some of these patients actually have unrecognized HBV infections. Thirty newly diagnosed HCC patients from Kurume, Japan, with antibody to the hepatitis C virus (anti-HCV) were studied. None of the 30 had HBsAg detectable in their serum. Of 22 for whom test results for antibodies to the hepatitis B core antigen (anti-HBc) and antibodies to HBsAg (anti-HBs) were available, 14 (64%) had anti-HBc and anti-HBs, four (18%) had anti-HBc alone, and four (18%) had no HBV markers. Nested polymerase chain reaction was used to detect the HBV surface (S), core (C), polymerase (P) and core promoter gene sequences in the HCC tissues and in the adjacent nontumorous liver tissues. HBV DNA was detected in HCC and/or adjacent nontumorous liver in 22 of 30 (73%) patients [detected in both HCC and nontumorous liver in 19/30 patients (63%)]. Among the 22 patients with detectable HBV DNA, more than one HBV gene was detected in 10 (46%). Among the four patients whose sera were negative for all HBV markers, three had HBV DNA in either HCC and nontumorous liver (two cases) or only in the nontumorous liver (one case); HBV DNA could not be detected in tissues from the fourth patient. In 18 of 21 (86%) patients with detectable HBV core promoter sequences, mutations at both nucleotides 1762 (A-GT) and 1764 (G-A) in the core promoter region were found. No deletions were detected in the core promoter gene region of the type reported to be associated with some cases of HBsAg-negative HBV infection. Thus, HBV DNA was detectable in 22 (73%) HBsAg-negative, anti-HCV-positive HCCs, including three (10%) who were also negative for anti-HBc and anti-HBs. HBV mutations at both nucleotides 1762 (A-GT) and 1764 (G-A) in the core promoter region were found in the majority of cases, mutations that have previously been reported in HBV that is integrated in HCC DNA. In serologic surveys to determine etiologic associations of HCC, patients such as those in this study would have been incorrectly designated as having 'HCV-associated HCC,' whereas the data in this study suggest that HBV could have played a role in the development of their HCCs.     

Intrahepatic hepatitis B virus covalently closed circular DNA can be a predictor of sustained response to therapy

BACKGROUND & AIMS: This study aimed to determine whether intrahepatic hepatitis B virus (HBV) covalently closed circular (ccc) DNA and total HBV DNA levels at the end of therapy would predict sustained response to therapy. METHODS: Hepatitis B e antigen (HBeAg)-positive chronic hepatitis B patients receiving either lamivudine monotherapy or combination of peginterferon and lamivudine had liver biopsy at the end of 1 year therapy and were followed for 52 more weeks after cessation of therapy. Serum HBV DNA, intrahepatic HBV ccc DNA, and total HBV DNA levels were determined. RESULTS: Forty-seven patients, including 34 males and 13 females, were studied. Twenty-seven patients received combination therapy, and 20 patients received lamivudine monotherapy. Twenty-nine patients had end-of-treatment virologic response, and 15 patients had sustained response 52 weeks after therapy. At the end of treatment, log serum HBV DNA levels correlated well with log intrahepatic HBV cccDNA and log intrahepatic total HBV DNA levels. Log intrahepatic cccDNA and log intrahepatic total DNA levels were significantly lower among patients with sustained virologic response. The adjusted odds ratio for log cccDNA was 5.3 (95% CI: 1.5-18.2, P = .009) and, for log intrahepatic HBV DNA, was 4.4 (95% CI: 1.3-14.7, P = .015) to predict sustained virologic response. Using log cccDNA at -0.80 copies/genome equivalent as cutoff, the sensitivity, specificity, and positive and negative predictive values and accuracy of predicting sustained virologic response were 73%, 78%, 56%, 86%, and 77% respectively. CONCLUSIONS: Intrahepatic HBV cccDNA and intrahepatic total HBV DNA levels at the end of therapy are superior to serum HBV DNA as surrogates of sustained virologic response.