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Bello KE, Mat Jusoh TNA, Irekeola AA, Abu N, Mohd Amin NAZ, Mustaffa N, Shueb RH. A Recent Prevalence of Hepatitis B Virus (HBV) Genotypes and Subtypes in Asia: A Systematic Review and Meta-Analysis. Healthcare (Basel) 2023; 11:healthcare11071011. [PMID: 37046937 PMCID: PMC10094200 DOI: 10.3390/healthcare11071011] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2023] [Revised: 03/24/2023] [Accepted: 03/27/2023] [Indexed: 04/05/2023] Open
Abstract
Background and Aim: Despite introducing the hepatitis B virus (HBV) vaccine, the incidence of the Hepatitis B virus globally is still a major health concern. This systematic review and meta-analysis were conducted to provide detailed information on the prevalence of HBV genotypes and subtypes in circulation in Asia. Methods: A systematic search for articles describing the prevalence of HBV genotypes and subtypes in Asia was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA) guidelines. Results: Our search returned 207 eligible articles involving 49,279 genotypes and 7457 subtypes representing 28 Asian countries. A meta-analysis was performed on our eligible studies using the Random effect Model. The pooled prevalence of HBV genotypes showed that genotype C (30.9%) (95% CI, 27.5–34.5%; I2 = 97.57%; p < 0.001) was the most common HBV genotype in Asia, followed by genotype B (17.8%) (95% CI, 15.5–20.4%; I2 = 97.26%; p < 0.001) and genotype D (15.4%) (95% CI, 11.8–19.8%). Vietnam had the highest prevalence of genotype B, Lebanon had the highest prevalence of genotypes C, and Jordan had the highest prevalence of genotype D. There was variation in genotypic prevalence with respect to the target genes for HBV genotyping. Reverse dot blot hybridization had the highest estimate of genotypes B and C. HBV subtype C2 (40.0%) (95% CI, 33.3–47.0) is the most prevalent HBV subtype. Conclusion: Evidence from this study reveals that HBV genotypes C and B are the most dominant HBV genotypes in Asia, and HBV subtype C2 is more endemic in Asia.
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Affiliation(s)
- Kizito Eneye Bello
- Department of Medical Microbiology and Parasitology, School of Medical Sciences, Universiti Sains Malaysia, Health Campus, Kubang Kerian 16150, Kelantan, Malaysia
- Department of Microbiology, Faculty of Natural Science, Kogi State University (Prince Abubakar Audu University), Anyigba 1008, Kogi State, Nigeria
| | - Tuan Nur Akmalina Mat Jusoh
- Department of Medical Microbiology and Parasitology, School of Medical Sciences, Universiti Sains Malaysia, Health Campus, Kubang Kerian 16150, Kelantan, Malaysia
| | - Ahmad Adebayo Irekeola
- Department of Medical Microbiology and Parasitology, School of Medical Sciences, Universiti Sains Malaysia, Health Campus, Kubang Kerian 16150, Kelantan, Malaysia
- Microbiology Unit, Department of Biological Sciences, College of Natural and Applied Sciences, Summit University Offa, Offa 4412, Kwara State, Nigeria
| | - Norhidayah Abu
- Department of Medical Microbiology and Parasitology, School of Medical Sciences, Universiti Sains Malaysia, Health Campus, Kubang Kerian 16150, Kelantan, Malaysia
- Advanced Materials Research Centre (A.M.R.E.C.), Lot 34 Jalan Hi-Tech 2/3, Kulim Hi-Tech Park, Kulim 09000, Kedah, Malaysia
| | - Nur Amalin Zahirah Mohd Amin
- Department of Medical Microbiology and Parasitology, School of Medical Sciences, Universiti Sains Malaysia, Health Campus, Kubang Kerian 16150, Kelantan, Malaysia
| | - Nazri Mustaffa
- Department of Medicine, School of Medical Sciences, Universiti Sains Malaysia, Health Campus, Kubang Kerian 16150, Kelantan, Malaysia
- Hospital Universiti Sains Malaysia, Kubang Kerian 16150, Kelantan, Malaysia
| | - Rafidah Hanim Shueb
- Department of Medical Microbiology and Parasitology, School of Medical Sciences, Universiti Sains Malaysia, Health Campus, Kubang Kerian 16150, Kelantan, Malaysia
- Institute for Research in Molecular Medicine (I.N.F.O.R.M.M.), Universiti Sains Malaysia, Kubang Kerian 16150, Kelantan, Malaysia
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Hsu HY, Chen HL, Chiang CL, Lai MW, Mu SC, Wen WH, Cheng SW, Hu JJ, Chang KC, Lee CN, Liu CJ, Wu JF, Ni YH, Chang MH. Characterization of Hepatitis B Virus in Tenofovir-Treated and Untreated Chronically Infected Mothers and Their Immunoprophylaxis Failure Infants. Clin Infect Dis 2023; 76:e783-e790. [PMID: 35789261 DOI: 10.1093/cid/ciac539] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2021] [Revised: 06/22/2022] [Accepted: 06/29/2022] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND Maternal tenofovir disoproxil fumarate (TDF) therapy during late pregnancy can reduce mother-to-infant transmission of hepatitis B virus (HBV). We investigated HBV mutations associated with maternal TDF therapy and their role in infant immunonophylaxis failure (IPF). METHODS Serum samples from untreated (n = 89) and TDF-treated (n = 68), highly viremic, chronically infected mothers and their infants were analyzed for HBV DNA by nested polymerase chain reaction (PCR) and direct sequencing. RESULTS At delivery, compared with untreated mothers, TDF-treated mothers had a lower HBV DNA titer and a higher frequency of basal core promoter (BCP) gene mutations, but they had similar frequencies in pre-S/S and pre-core/core mutations. The 14 mothers harboring surface "a" determinant mutants did not transmit the mutants to their immunized infants. Such mutants were found in 3 of 13 IPF infants; the 13 mothers had wild-type hepatitis B surface antigen (HBsAg). In univariable analysis, maternal HBV DNA titer (odds ratio [OR]: 1.54; 95% confidence intervals [CI]: 1.02-2.33; P = .039), genotype C (OR: 4.18; 95% CI: 1.28-13.62; P = .018) and pre-S1 wild-type sequence (OR: 6.33; 95% CI: 1.85-21.68; P = .003) at delivery were associated with infant IPF. Multivariable analyses showed that maternal genotype C (OR: 3.71; 95% CI: 1.11-12.36; P = .033) and pre-S1 wild-type (OR: 6.34; 95% CI: 1.79-22.44; P = .004) were associated with infant IPF independently of maternal viremia. CONCLUSIONS Along with high maternal HBV DNA titer at delivery, maternal genotype C and pre-S1 wild-type sequence were potential risk factors for infant IPF, although BCP mutations were not. The offspring of pregnant women harboring "a" determinant mutants as major strains seemed to be protected by immunoprophylaxis. CLINICAL TRIALS REGISTRATION NCT01312012.
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Affiliation(s)
- Hong-Yuan Hsu
- Department of Pediatrics, National Taiwan University College of Medicine and Hospital, Taipei, Taiwan.,Department and Graduate Institute of Medical Education and Bioethics National Taiwan University College of Medicine, Taipei, Taiwan
| | - Huey-Ling Chen
- Department of Pediatrics, National Taiwan University College of Medicine and Hospital, Taipei, Taiwan.,Department and Graduate Institute of Medical Education and Bioethics National Taiwan University College of Medicine, Taipei, Taiwan
| | - Cheng-Lun Chiang
- Department of Pediatrics, National Taiwan University College of Medicine and Hospital, Taipei, Taiwan.,Department and Graduate Institute of Medical Education and Bioethics National Taiwan University College of Medicine, Taipei, Taiwan
| | - Ming-Wei Lai
- Division of Pediatric Gastroenterology, Department of Pediatrics; Liver Research Center, Chang Gung Memorial Hospital, Linkou Branch, Taiwan
| | - Shu-Chi Mu
- Department of Pediatrics, Shin Kong Wu Ho-Su Memorial Hospital, Taipei, Taiwan
| | - Wan-Hsin Wen
- Department of Pediatrics, Cardinal Tien Hospital, and School of Medicine, Fu-Jen Catholic University, New Taipei City, Taiwan
| | - Shao-Wen Cheng
- Department of Pediatrics, Chang Gung Memorial Hospital, Taipei Branch, Taiwan
| | - Jen-Jan Hu
- Department of Pediatrics, Taiwan Adventist Hospital, Taipei, Taiwan
| | - Kai-Chi Chang
- Department of Pediatrics, National Taiwan University College of Medicine and Hospital, Taipei, Taiwan
| | - Chien-Nan Lee
- Department of Obstetrics and Gynecology, National Taiwan University College of Medicine and Hospital, Taipei, Taiwan
| | - Chun-Jen Liu
- Department of Internal Medicine, National Taiwan University College of Medicine and Hospital, Taipei, Taiwan
| | - Jia-Feng Wu
- Department of Pediatrics, National Taiwan University College of Medicine and Hospital, Taipei, Taiwan
| | - Yen-Hsuan Ni
- Department of Pediatrics, National Taiwan University College of Medicine and Hospital, Taipei, Taiwan
| | - Mei-Hwei Chang
- Department of Pediatrics, National Taiwan University College of Medicine and Hospital, Taipei, Taiwan
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Residual HBV DNA and pgRNA viraemia is associated with hepatocellular carcinoma in chronic hepatitis B patients on antiviral therapy. J Gastroenterol 2021; 56:479-488. [PMID: 33772643 DOI: 10.1007/s00535-021-01780-5] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/23/2020] [Accepted: 03/16/2021] [Indexed: 02/04/2023]
Abstract
BACKGROUND We aimed to assess whether residual hepatitis B virus (HBV) viraemia is associated with HCC development. METHODS This is a case-control study of 104 patients [52 HCC and 52 non-HCC (matched with age, gender, cirrhosis and treatment duration)] on ≥ 3 years entecavir (ETV) with unquantifiable HBV DNA by Cobas Taqman assay v2.0 (Roche Diagnostics; lower limit of quantification [LLOQ] 20 IU/mL). Serial sera within 1, 1-2, and > 2 years prior to HCC diagnosis or last follow-up (LFU) were measured for HBV DNA and pre-genomic (pg) RNA using a highly sensitive semi-quantitative PCR assay with lower limit of detection of 10 IU/mL and LLOQ of 51.5 IU/mL, respectively. RESULTS Among the 104 patients (80.8% male, median age 61.2 years old, 38.5% cirrhosis, median duration of ETV 45.5 months), 38.5% and 9.6% HCC patients had undetectable serum DNA and pgRNA, respectively, compared to 65.4% and 36.5% in non-HCC patients; P = 0.005 & 0.001, respectively, at the time of HCC diagnosis/LFU. Detectable HBV DNA and pgRNA were associated with a higher 2-year risk of HCC development (HR 2.79, 95% CI 1.424-5.468 & HR 4.544, 95% CI 1.07-19.289, respectively). No significant differences were observed for qHBsAg levels between HCC and non-HCC patients. CONCLUSIONS More than 50% CHB patients on ETV with HBV DNA < LLOQ by standard assay had persistent viraemia as determined by a more sensitive assay. Detectable HBV DNA or pgRNA by more sensitive assays was associated with HCC development. More potent viral suppression is required to further reduce the risk of HCC.
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Velkov S, Protzer U, Michler T. Global Occurrence of Clinically Relevant Hepatitis B Virus Variants as Found by Analysis of Publicly Available Sequencing Data. Viruses 2020; 12:v12111344. [PMID: 33238650 PMCID: PMC7700573 DOI: 10.3390/v12111344] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2020] [Revised: 11/18/2020] [Accepted: 11/20/2020] [Indexed: 12/14/2022] Open
Abstract
Several viral factors impact the natural course of hepatitis B virus (HBV) infection, the sensitivity of diagnostic tests, or treatment response to interferon-α and nucleos(t)ide analogues. These factors include the viral genotype and serotype but also mutations affecting the HBV surface antigen, basal core promoter/pre-core region, or reverse transcriptase. However, a comprehensive overview of the distribution of HBV variants between HBV genotypes or different geographical locations is lacking. To address this, we performed an in silico analysis of publicly available HBV full-length genome sequences. We found that not only the serotype frequency but also the majority of clinically relevant mutations are primarily associated with specific genotypes. Distinct mutations enriched in certain world regions are not explained by the local genotype distribution. Two HBV variants previously identified to confer resistance to the nucleotide analogue tenofovir in vitro were not identified, questioning their translational relevance. In summary, our work elucidates the differences in the clinical manifestation of HBV infection observed between genotypes and geographical locations and furthermore helps identify suitable diagnostic tests and therapies.
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Affiliation(s)
- Stoyan Velkov
- Institute of Virology, Technical University of Munich/Helmholtz Zentrum München, Trogerstrasse 30, D-81675 München, Germany; (S.V.); (U.P.)
| | - Ulrike Protzer
- Institute of Virology, Technical University of Munich/Helmholtz Zentrum München, Trogerstrasse 30, D-81675 München, Germany; (S.V.); (U.P.)
- German Center for Infection Research (DZIF), Munich Partner Site, D-81675 Munich, Germany
| | - Thomas Michler
- Institute of Virology, Technical University of Munich/Helmholtz Zentrum München, Trogerstrasse 30, D-81675 München, Germany; (S.V.); (U.P.)
- German Center for Infection Research (DZIF), Munich Partner Site, D-81675 Munich, Germany
- Correspondence: ; Tel.: +49-89-4140-6814
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Su QD, Zhang S, Wang F, Liu H, Zhang GM, Zheng H, Qiu F, Sun XJ, Liang XF, Bi SL, Shen LP, Wang FZ. Epidemiological distribution of hepatitis B virus genotypes in 1-29-year-olds in the mainland of China. Vaccine 2020; 38:8238-8246. [PMID: 33187763 DOI: 10.1016/j.vaccine.2020.09.083] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2020] [Revised: 08/10/2020] [Accepted: 09/17/2020] [Indexed: 12/20/2022]
Abstract
BACKGROUND To analyze the epidemiological distribution of Hepatitis B virus (HBV) genotype in the mainland of China following the implementation of effective preventive measures. METHODS Five hundred and seventeen HBsAg-positive subjects aged 1-29 years surveyed in the 2014 national HBV sero-survey in the mainland of China were enrolled in the study. The full-length HBV genome was obtained by PCR amplification and sequencing. The HBV genotype was determined by phylogenetic analysis. Combined with questionnaire information, HBV genotype distribution was analyzed. RESULTS Of the 517 HBsAg-positive subjects, 369 (71.4%) were included in the analysis. HBV genotypes found were B (45.0%), C (36.6%), D (6.0%), C/D (9.8%), B/C (2.2%), and I (0.5%). Geographic differences in HBV genotype were significant for seven regions. Three serotypes were found: adw (47.2%), adr (35.5%), and ayw (17.3%). B2 (43.9%) and C2 (25.2%) were the two major subgenotypes. The predominant genotypes differed between the Han group and the other ethnic groups. No statistical differences in genotype distribution were found by gender, age group, or hepatitis B (HepB) vaccination history. CONCLUSION The prevalence of HBV genotype B was higher than that of genotype C with subgenotypes B2 and C2 endemic in 1-29-year-olds in the mainland of China, after HBV prevalence has reduced significantly due to the implementation of preventive measures. HepB vaccination or other factors did not interfere with HBV genotype distribution. The surveillance of HBV genotype was essential for responding to the potential changes and impact on the preventive policies in the future.
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Affiliation(s)
- Qiu-Dong Su
- National Institute For Viral Disease Control and Prevention, Chinese Center For Disease Control and Prevention, Beijing 102206, China
| | - Shuang Zhang
- National Institute For Viral Disease Control and Prevention, Chinese Center For Disease Control and Prevention, Beijing 102206, China
| | - Feng Wang
- National Institute For Viral Disease Control and Prevention, Chinese Center For Disease Control and Prevention, Beijing 102206, China
| | - He Liu
- National Institute For Viral Disease Control and Prevention, Chinese Center For Disease Control and Prevention, Beijing 102206, China
| | - Guo-Min Zhang
- National Immunization Program, Chinese Center For Disease Control and Prevention, Beijing 100051, China
| | - Hui Zheng
- National Immunization Program, Chinese Center For Disease Control and Prevention, Beijing 100051, China
| | - Feng Qiu
- National Institute For Viral Disease Control and Prevention, Chinese Center For Disease Control and Prevention, Beijing 102206, China
| | - Xiao-Jin Sun
- National Immunization Program, Chinese Center For Disease Control and Prevention, Beijing 100051, China
| | - Xiao-Feng Liang
- National Immunization Program, Chinese Center For Disease Control and Prevention, Beijing 100051, China
| | - Sheng-Li Bi
- National Institute For Viral Disease Control and Prevention, Chinese Center For Disease Control and Prevention, Beijing 102206, China
| | - Li-Ping Shen
- National Institute For Viral Disease Control and Prevention, Chinese Center For Disease Control and Prevention, Beijing 102206, China.
| | - Fu-Zhen Wang
- National Immunization Program, Chinese Center For Disease Control and Prevention, Beijing 100051, China
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Abstract
At least 10 hepatitis B virus (HBV) genotypes (A to J) with distinct geographic distributions and several HBV mutants, including precore/core promoter mutations and pre-S/S deletion mutations, have been recognized to be not only predictive of liver disease progression but also associated with response to antiviral therapy. HBV genotype-specific pathogenesis may contribute to heterogeneous clinical outcomes in chronic hepatitis B patients across the world. For example, patients with HBV genotypes C and D infection have a lower rate of spontaneous HBeAg seroconversion. In addition, HBV genotypes C and D have a higher frequency of core promoter and pre-S mutations than genotypes A and B. Genotypes C and D also carry a higher lifetime risk of cirrhosis and HCC development than genotypes A and B. Core promoter and pre-S mutations also correlate with an increased risk of hepatocellular carcinoma (HCC). Therapeutically, genotypes A and B patients have a better response to interferon-based therapy than genotypes C and D patients, but the response to nucleos(t)ide analogs is comparable across different HBV genotypes. In conclusion, HBV genotypes and variants may serve as viral genetic markers to predict disease progression as well as help practicing physicians optimize individualized antiviral therapy in clinical practice.
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Affiliation(s)
- Chih-Lin Lin
- Department of Gastroenterology, Ren-Ai Branch, Taipei City Hospital, Taipei 106, Taiwan Department of Psychology, National Chengchi University, Taipei 106, Taiwan
| | - Jia-Horng Kao
- Department of Internal Medicine, National Taiwan University Hospital, Taipei 100, Taiwan Graduate Institute of Clinical Medicine, National Taiwan University College of Medicine and National Taiwan University Hospital, Taipei 100, Taiwan Hepatitis Research Center, National Taiwan University College of Medicine and National Taiwan University Hospital, Taipei 100, Taiwan Department of Medical Research, National Taiwan University College of Medicine and National Taiwan University Hospital, Taipei 100, Taiwan
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Zheng Y, Zhang S, Tan Grahn HM, Ye C, Gong Z, Zhang Q. Prophylactic Lamivudine to Improve the Outcome of Breast Cancer Patients With HBsAg Positive During Chemotherapy: A Meta-Analysis. HEPATITIS MONTHLY 2013; 13:e6496. [PMID: 23805156 PMCID: PMC3693540 DOI: 10.5812/hepatmon.6496] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/13/2012] [Revised: 11/10/2012] [Accepted: 12/31/2012] [Indexed: 12/11/2022]
Abstract
CONTEXT Raising the chemotherapy-induced HBV reactivation is parallel to the increment of chemotherapy treatments in breast cancer patients. This meta-analysis aims to evaluate the efficacy of prophylactic use of lamivudine in breast cancer patients with HBsAg positive during chemotherapy. EVIDENCE ACQUISITION MEDLINE, Pubmed, Ovid and Embase were used to search for clinical studies comparing with or without prophylactic use of lamivudine for HBV reactivation in breast cancer patients receiving chemotherapy. Outcomes of interest were the rate of HBV reactivation, incidence of hepatitis and incidence of hepatitis attributable to HBV reactivation, severity of hepatitis and severity of hepatitis attributable to HBV reactivation, the rate of chemotherapy disruption, and the rate of chemotherapy disruption attributable to HBV reactivation, overall mortality, and mortality attributable to HBV reactivation. RESULTS Four studies with 285 patients were included in this meta-analysis. The rate of HBV reactivation, incidence of hepatitis and incidence of hepatitis related to HBV reactivation were reduced by use of prophylactic lamivudine compared to control group. Pooled Odds Ratios (ORs) were 0.09 (95% confidence intervals [CI] 0.03-0.26; P < 0.0001), 0.23 (95% CI 0.06-0.92; P = 0.04), and 0.10 (95% CI 0.03-0.32; P < 0.0001) respectively. There was a reduction in chemotherapy disruption related to HBV reactivation by use of prophylactic lamivudine (pooled OR = 0.11; 95% CI 0.02-0.58; P = 0.01). Chemotherapy disruption, overall mortality, and mortality attributable to HBV reactivation were not significantly different between two groups. Pooled ORs were 0.42 (95% CI 0.11-1.58; P = 0.20), 0.37 (95% CI 0.07-2.04; P = 0.25), and 0.25 (95% CI 0.01-6.82; P = 0.41) respectively. Lamivudine was well-tolerated, and no additional toxicity was observed. CONCLUSIONS Use of prophylactic lamivudine may have positive effect on the outcome of breast cancer patients with HBsAg positive during chemotherapy.
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Affiliation(s)
- Yihu Zheng
- Department of General Surgery, The First Affiliated Hospital, Wenzhou Medical College, Wenzhou, Zhejiang, China
| | - Shengchu Zhang
- Department of General Surgery, The First Affiliated Hospital, Wenzhou Medical College, Wenzhou, Zhejiang, China
- Department of General Surgery, Yichang Central People’s Hospital, The First Clinical Medical College of Three Gorges University, Yichang, China
| | - Hooi Min Tan Grahn
- Metabolism, Obesity/Diabetes, Department of Biochemistry, Boston University School of Medicine, Boston, USA
| | - Chao Ye
- State Key Laboratory for Diagnosis and Treatment of Infectious Disease, The First Affiliated Hospital, Zhejiang University, Hangzhou, China
| | - Zheng Gong
- Department of General Surgery, Yichang Central People’s Hospital, The First Clinical Medical College of Three Gorges University, Yichang, China
| | - Qiyu Zhang
- Department of General Surgery, The First Affiliated Hospital, Wenzhou Medical College, Wenzhou, Zhejiang, China
- Corresponding author: Qiyu Zhang, Department of General Surgery, The First Affiliated Hospital of Wenzhou Medical College, NO. 453 Ward, No. 4 Building, Nan Bai Xiang Street, Ouhai District, Wenzhou, Zhejiang, China. Tel.: +86-57788288181, Fax: 86-57788069555, E-mail:
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Michailidis E, Kirby KA, Hachiya A, Yoo W, Hong SP, Kim SO, Folk WR, Sarafianos SG. Antiviral therapies: focus on hepatitis B reverse transcriptase. Int J Biochem Cell Biol 2012; 44:1060-71. [PMID: 22531713 DOI: 10.1016/j.biocel.2012.04.006] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2012] [Revised: 04/04/2012] [Accepted: 04/05/2012] [Indexed: 12/20/2022]
Abstract
Hepatitis B virus (HBV) is the etiologic agent of mankind's most serious liver disease. While the availability of a vaccine has reduced the number of new HBV infections, the vaccine does not benefit the approximately 350 million people already chronically infected by the virus. Most of the drugs approved by the FDA for the treatment of hepatitis B target the reverse transcriptase (RT or P gene product) and are nucleoside RT inhibitors (NRTIs) that suppress viral replication. However, prolonged monotherapies directed against a single target result in the emergence of viral resistance. HBV genotypic differences affect NRTI resistance, and because the reading frames of the S (surface antigen) and P genes partially overlap, genomic differences that affect the surface of the virus may also alter the viral polymerase sequence, function and drug susceptibility. The scope of this review is to assess the effects of HBV genotypic variation on the development of drug resistance to NRTIs. Some RT residues that vary among different genotypes are in the vicinity of residues that mutate and give rise to NRTI resistance. Interactions between these amino acids can help explain the effect of HBV genotype on the development of NRTI resistance during antiviral therapies, and might help in the design of improved therapeutic strategies.
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Affiliation(s)
- Eleftherios Michailidis
- Christopher S. Bond Life Sciences Center, Department of Molecular Microbiology & Immunology, University of Missouri, Columbia, MO 65211, USA
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Yıldız O, Aygen B, Demirtürk N, Demirdal T, Inan D, Yıldırmak T, Kantürk A, Tütüncü E, Group HBS. Lamivudine resistance mutations in patients infected with hepatitis B virus genotype D. World J Gastroenterol 2011; 17:4987-92. [PMID: 22174548 PMCID: PMC3236585 DOI: 10.3748/wjg.v17.i45.4987] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/06/2011] [Revised: 07/04/2011] [Accepted: 07/11/2011] [Indexed: 02/06/2023] Open
Abstract
AIM: To determine the distribution of viral genotypes for primary or acquired lamivudine resistance.
METHODS: A total of 283 patients with chronic hepatitis B virus (HBV) infection (245 patients with chronic hepatitis B and 38 inactive hepatitis B surface antigen carriers) were included in the study. The HBV genotype was determined by using quantitative real-time polymerase chain reaction and sequence analysis, and tyrosine-methionine-aspartate-aspartate (YMDD) motif mutations were determined using the reverse transcriptase hybridization method.
RESULTS: Lamivudine resistance was determined in a total of 25 (10.7%) chronic hepatitis B patients. Eight subjects (4%) had primary resistance to lamivudine, and 17 (53.1%) had secondary resistance to lamivudine. Genotype D, which was isolated from 267 of the patients with chronic HBV infection, was the dominant genotype in Turkey.
CONCLUSION: Identification of YMDD motif mutations should have a positive impact on the selection of proper antiviral medication for patients, even for those who are nucleoside naïve.
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Nien HC, Sheu JC, Kao JH, Chou HC, Su CW, Chen CH. Aboriginal Taiwanese hepatitis B carriers have more favorable viral factors than Han Chinese carriers. J Med Virol 2011; 83:1326-31. [PMID: 21678436 DOI: 10.1002/jmv.22135] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Several viral factors are associated with disease progression in hepatitis B virus (HBV) carriers. Compared with Taiwanese Han Chinese, Taiwanese aborigines have a higher prevalence of chronic HBV infection and a higher standardized mortality rate of chronic liver diseases but a lower standardized mortality rate of hepatocellular carcinoma (HCC). The aim of this study was to investigate whether aboriginal Taiwanese HBV carriers have more favorable viral factors which reduce the risk for HCC than Han Chinese carriers. Blood samples from 3,488 HBV carriers (1,527 aborigines and 1,961 Han Chinese) were assayed for aminotransferases, hepatitis B e antigen (HBeAg), HBV DNA, and HBV genotype. Aboriginal HBV carriers had a lower HBeAg-positive rate (5.3% vs. 10.2%, P < 0.0001) and a lower viral load of HBV DNA > 2,000 IU/ml (27.4% vs. 36.7%, P < 0.0001) but a higher rate of alcohol consumption (40.0% vs. 19.3%, P < 0.0001) than Han Chinese carriers. The prevalence of HBV genotype B in aboriginal carriers (92.7%) was significantly higher than that in Han Chinese carriers (72.7%) in all age groups (P < 0.05). In addition, patients with rare genotype D infections were clustered in a township in southern Taiwan. In conclusion, aboriginal Taiwanese HBV carriers have more favorable viral factors than Han Chinese carriers, which may be partly responsible for the lower standardized mortality rate of HCC in Taiwanese aborigines.
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Affiliation(s)
- Hsiao-Ching Nien
- Liver Disease Prevention and Treatment Research Foundation, Taipei, Taiwan
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Yang MH, Li L, Hung YS, Hung CS, Allain JP, Lin KS, Tsai SJL. The efficacy of individual-donation and minipool testing to detect low-level hepatitis B virus DNA in Taiwan. Transfusion 2010; 50:65-74. [PMID: 19709394 DOI: 10.1111/j.1537-2995.2009.02357.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
BACKGROUND Financial constraints are the main concern in implementing nucleic acid testing (NAT) as routine blood screening in Taiwan. The PROCLEIX ULTRIO assay (Ultrio) on the TIGRIS System (Novartis Diagnostics) was evaluated for its operational performance both for individual-donation testing (IDT) and in minipools of 4 (MP4) to develop a feasible solution. STUDY DESIGN AND METHODS Analytical sensitivity was determined by testing WHO international standards. We tested 10,290 blood donors, 4210 in IDT and 6080 in MP4. Potential hepatitis B virus (HBV) yield donors (hepatitis B surface antigen [HBsAg] negative/NAT reactive) were evaluated for up to 9 months' follow-up. Discordant results between the Ultrio assay and the HBsAg tests were further analyzed by HBV antibody serology, alternative NATs, HBV DNA quantification, and sequencing. RESULTS The 95% limits of detection in IU/mL (95% confidence interval) were as follows: human immunodeficiency virus Type 1 (HIV-1), 18 (12-34); hepatitis C virus (HCV), 4.4 (2.8-8.9); and HBV, 6.3 (4.4-11). The retest rates were 0.55% for IDT and 0.33% for MP4. No HIV or HCV yield cases were found, while there were 12 potential HBV yield cases, nine from IDT and three from MP4 testing. Eleven of them were successfully genotyped as B2. Ten of them returned for follow-up and mostly were determined as occult HBV infection (OBI). The IDT yield rate of 9 in 4210 (0.21%) was fourfold greater than the MP4 yield rate of 3 in 6080 (0.05%; p < 0.05). CONCLUSION The higher yield rate for IDT versus MP4 demonstrates the benefit to implement a more sensitive NAT strategy in regions having significant OBI carriers such as Taiwan.
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Affiliation(s)
- Meng-Hua Yang
- Taipei Blood Center, Taiwan Blood Services Foundation, Taipei, Taiwan
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12
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Tonetto PA, Gonçales NSL, Fais VC, Vigani AG, Gonçales ESL, Feltrin A, Gonçales FL. Hepatitis B virus: molecular genotypes and HBeAg serological status among HBV-infected patients in the southeast of Brazil. BMC Infect Dis 2009; 9:149. [PMID: 19737394 PMCID: PMC2749048 DOI: 10.1186/1471-2334-9-149] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2009] [Accepted: 09/08/2009] [Indexed: 12/18/2022] Open
Abstract
BACKGROUND Knowledge of HBV genotype is very important for clinical treatment. Studies have suggested possible pathogenic and therapeutic differences among HBV genotypes. The aim of this study was to determine HBV subtypes and genotypes in HBV-infected patients in our region (southeast Brazil) and to correlate results with clinical and histopathological data. METHODS One hundred and thirty-nine HBsAg-positive patients were included in the study. All patients were anti-HCV and anti-HIV negative (64% male; mean age 42 +/- 14.5 years; range 7-80 years; 84% Caucasian) and were followed up at the University Hospital. A method for genotyping and subtyping HBV by partial HBsAg gene sequencing with primers common to all known genotypes was used. The viral load was measured by Amplicor Monitor assay (Roche). RESULTS HBV genotype A was the most prevalent (55%), while genotypes C, D and F were found in 3%, 38% and 4% of HBV-infected patients, respectively. Among the patients infected by genotype A, 18.3% (14/76) were African descendents and, among the patients infected by genotype D, 11.3% (6/53) were also African descendents. In the four patients infected with genotype C, 2 were Asian descendents and 2 were Caucasians. All (7) genotype F infected patients were Caucasians. Seventy percent of our HBsAg-positive patients were HBeAg negative (62% genotypes A; 26.2% D; 7.1% C and 4.7%F). The viral load of HBV-DNA was about 5 times higher in HBeAg-positive than in HBeAg-negative patients. About 40% of these patients had alanine aminotransferase of up to 1.5 times the normal level. The mean stage of fibrosis in genotype A patients (2.8) was significantly higher than the mean stage of fibrosis in genotype D patients (2.0) (P = 0.0179). CONCLUSION The genotypes encountered in our HBV-infected patients were apparently a consequence of the types of immigration that occurred in our region, where European and African descendents predominate. The HBeAg-negative status predominated, possibly due to the length of time of infection. The viral load in HBeAg-positive patients was higher than in HBeAg-negative individuals. The fibrosis grade in genotype A-infected patients was more advanced than genotype D-infected patients.
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Affiliation(s)
- Priscila A Tonetto
- Grupo de Estudo das Hepatites - Disciplina de Moléstias Infecciosas, Departamento de Clínica Médica - Faculdade de Ciências Médicas - Universidade Estadual de Campinas - UNICAMP, São Paulo, Brazil.
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Nguyen LH, Ha NB, Vutien P, Ha NB, Garcia RT, Trinh HN, Levitt BS, Nguyen HA, Nguyen KK, Keeffe EB, Nguyen MH. Prevalence of hepatitis B virus genotype B in Vietnamese patients with chronic hepatitis B. Hepatol Int 2009; 3:461-7. [PMID: 19669244 DOI: 10.1007/s12072-009-9141-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/08/2008] [Revised: 03/31/2009] [Accepted: 04/13/2009] [Indexed: 01/05/2023]
Abstract
PURPOSE Hepatitis B virus (HBV) genotypes can affect treatment response to interferon-based therapy and disease outcomes in patients with chronic hepatitis B (CHB). Little data exist to characterize HBV genotypes in Vietnamese, one of the largest minority groups in the United States and also one with one of the highest CHB and liver cancer disease burdens. The goal of this study was to compare the distribution of HBV genotypes in Vietnamese and Chinese patients. METHODS We performed a cross-sectional study of 567 consecutive patients of Vietnamese (n = 478) or Chinese (n = 89) descent, with HBV genotype mutation analysis performed between 7/2,005 and 6/2,008 at a community gastroenterology clinic and a university-affiliated liver clinic in the United States. RESULTS There were no significant differences between the Vietnamese and Chinese groups in mean age (45 and 44 years), gender (58% and 61% male), HBeAg status (64% and 65% negative), median alanine aminotransferase (33 and 41 U/L), and log(10) HBV DNA (4.9 and 5.0 log(10) IU/ml), or the prevalence of precore/basic core promoter mutations (72% and 71%), respectively. Vietnamese patients had a much higher prevalence of HBV genotype B and a lower prevalence of genotype C than Chinese patients: 74% and 25% vs. 55% and 43% (P = 0.001). CONCLUSIONS Chinese patients with CHB often carry either B or C genotype. Vietnamese patients with CHB mostly have HBV genotype B. Additional studies are needed to further characterize the clinical significance of HBV genotype in the natural history and treatment outcomes of CHB in Vietnamese patients.
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Nguyen VTT, Law MG, Dore GJ. An enormous hepatitis B virus-related liver disease burden projected in Vietnam by 2025. Liver Int 2008; 28:525-31. [PMID: 18266635 DOI: 10.1111/j.1478-3231.2007.01646.x] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
BACKGROUND Hepatitis B virus (HBV) is the major cause of chronic liver disease in Vietnam. This study aimed to estimate and project chronic HBV prevalence and HBV-related liver cirrhosis (LC) and hepatocellular carcinoma (HCC) for the period 1990-2025. METHOD The Vietnamese population for the period 1990-1999 was derived from census data to 1999 and from 2000 to 2025 based on projection data from the United States Census Bureau. Population chronic HBV prevalence for males and females was estimated based on age-specific HBV prevalence from Vietnamese community-based studies. Universal infant HBV vaccination from 2003 was assumed to reduce HBV infection by 90% in subsequent birth cohorts. Incidences of HBV-related LC and HCC by HBV DNA levels from the Taiwanese REVEAL studies were applied to the chronic HBV population to estimate and project HBV-related liver disease burden. RESULTS Estimated chronic HBV prevalence increased from 6.4 million cases in 1990 to around 8.4 million cases in 2005 and was projected to decrease to 8.0 million by 2025. Estimated HBV-related LC and HCC incidence increased linearly from 21,900 and 9400 in 1990 to 58,650 and 25,000 in 2025. Estimated HBV-related mortality increased from 12,600 in 1990 to 40,000 in 2025. CONCLUSION Over the next two decades, universal infant HBV vaccination will reduce chronic HBV prevalence in Vietnam but HBV-related liver disease burden will continue to rise. A national HBV strategy is required to address this expanding burden of liver disease.
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Affiliation(s)
- Van Thi Thuy Nguyen
- School of Public Health and Community Medicine, The University of New South Wales, Sydney, Australia.
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Alam MM, Zaidi SZ, Shaukat S, Sharif S, Angez M, Naeem A, Saleha S, Butt JA, Malik SA. Common genotypes of Hepatitis B virus prevalent in injecting drug abusers (addicts) of North West Frontier Province of Pakistan. Virol J 2007; 4:63. [PMID: 17597548 PMCID: PMC1910598 DOI: 10.1186/1743-422x-4-63] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2007] [Accepted: 06/28/2007] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND The epidemiological significance of Hepatitis B virus genotypes has been well established and becoming an essential concern day by day however, much little is known about the mixed infection with more than one Hepatitis B virus genotypes and their clinical relevance. METHODS Intravenous drug abusers are considered as a major risk group for the acquisition and transmission of blood borne infections like hepatitis B, however, in Pakistan, no such data has ever been reported about the epidemiology of HBV and its genotypes in Injecting Drug Users. 250 individuals were analyzed for hepatitis B virus genotypes after prior screening with serological assay for the detection of HBsAg. RESULTS 56 (22.4%) individuals were found positive on ELSIA for HBsAg. The genotype distribution was found to be as: genotype D, 62.5%; genotype A, 8.92% while 28.57% individuals were found to be infected with a mixture of genotype A and D. CONCLUSION There is an urgent need of the time to develop public health care policies with special emphasis towards the control of HBV transmission through high risk groups especially Injecting Drug Users.
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Affiliation(s)
| | - Sohail Zahoor Zaidi
- Head of Department of Virology; Principal Investigator-WHO Regional Reference Laboratory for Polio Eradication Initiative, National Institute of Health, Islamabad, Pakistan
| | - Shehzad Shaukat
- Department of Virology, National Institute of Health, Islamabad, Pakistan
| | - Salmaan Sharif
- Department of Virology, National Institute of Health, Islamabad, Pakistan
| | - Mehar Angez
- Department of Virology, National Institute of Health, Islamabad, Pakistan
| | - Asif Naeem
- Department of Virology, National Institute of Health, Islamabad, Pakistan
| | - Shamim Saleha
- Research Student, Department of Virology, National Institute of Health, Islamabad Pakistan
| | - Javed Aslam Butt
- Head of Department of Gastroenterology, Pakistan Institute of Medical Sciences, Islamabad, Pakistan
| | - Salman Akbar Malik
- Head of Department of Biochemistry, Quaid-i-azam University, Islamabad, Pakistan
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You J, Zhuang L, Chen HY, Yang HQ, Tang BZ, Huang ML. Advances in the researches on hepatitis B virus genotyping and its clinical significance. Shijie Huaren Xiaohua Zazhi 2007; 15:921-928. [DOI: 10.11569/wcjd.v15.i9.921] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
The genotyping of hepatitis B virus (HBV) is a highlight of the studies associated with chronic hepatitis B inside and outside the country nowadays. HBV infection can lead to chronic carriage of the virus and progressive liver disease, including liver cirrhosis and hepatocellular carcinoma. The serological heterogeneity of HBsAg has been well established. HBV isolates have been classified into 10 different subtypes according to the antigenic determinants of their HBsAg. However, the classification of HBV by serologic subtyping is not rational because a single point mutation at the S gene may result in a change in subtype. Therefore, worldwide HBV isolates have been classified into eight genotypes: A, B, C, D, E, F, G and H, based on the comparison of complete HBV genomes, which is the gold standard for genotyping. The eight genotypes have a distinct characteristic geographical distribution and an HBV genotypic difference in HBV pathogenicity. It has been reported that there are remarkable differences in the clinical and virologic characteristics between the patients with different genotypes. Studies have revealed the association of HBV genotypes with the severity and outcome of chronic liver disease, but the results including the influence of genotypes on therapeutic responses are not consistent.
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Alvarado-Esquivel C, Sablon E, Conde-González CJ, Juárez-Figueroa L, Ruiz-Maya L, Aguilar-Benavides S. Molecular analysis of hepatitis B virus isolates in Mexico: Predominant circulation of hepatitis B virus genotype H. World J Gastroenterol 2006; 12:6540-5. [PMID: 17072988 PMCID: PMC4100645 DOI: 10.3748/wjg.v12.i40.6540] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
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.
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Liu CJ, Lo SC, Kao JH, Tseng PT, Lai MY, Ni YH, Yeh SH, Chen PJ, Chen DS. Transmission of occult hepatitis B virus by transfusion to adult and pediatric recipients in Taiwan. J Hepatol 2006; 44:39-46. [PMID: 16168517 DOI: 10.1016/j.jhep.2005.06.016] [Citation(s) in RCA: 89] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/22/2005] [Revised: 06/06/2005] [Accepted: 06/17/2005] [Indexed: 01/01/2023]
Abstract
BACKGROUND/AIMS The infectivity of occult hepatitis B virus (HBV), defined as HBsAg-negative but HBV DNA-positive, after transfusion has been low but not negligible. To address this, we investigated the incidence of post-transfusion HBV infection after receiving screened blood units in Taiwan. METHODS Consecutive HBV-naïve (anti-HBc-negative) recipients with normal ALT were followed for HBV DNA and serologic markers before and after transfusion. Among 4448 blood recipients, 467 (10.5%) were anti-HBc-negative. Post-transfusion 6-month follow-up was completed for 327. We identified 5 (1.5%) who developed hepatitis B viremia 1 week after transfusion. Three were children who later seroconverted to anti-HBc but with normal ALT indicating subclinical acute infection, despite all had anti-HBs from previous vaccination. One had transient transfusion-transmitted HBV without seroconversion to anti-HBc and one possibly had occult HBV infection. Our findings suggested the possibility that occult HBV infection was transmissible by transfusion. The incidence of post-transfusion acute HBV infection was 0.9% (100 per million units) in naïve recipients in Taiwan, a figure 7 approximately 40-fold higher than in developed countries. Moreover, some vaccinated children with anti-HBs were still susceptible. CONCLUSIONS Therefore, despite active immunization, sensitive screening assays for occult HBV infection such as nucleic acid amplification test could be considered in endemic areas.
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Affiliation(s)
- Chun-Jen Liu
- Division of Gastroenterology, Department of Internal Medicine, National Taiwan University Hospital and National Taiwan University College of Medicine, 1 Chang-Te Street, Taipei 100, Taiwan
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20
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Dal Molin G, Poli A, Crocè LS, D'Agaro P, Biagi C, Comar M, Tiribelli C, Campello C. Hepatitis B virus genotypes, core promoter variants, and precore stop codon variants in patients infected chronically in North-Eastern Italy. J Med Virol 2006; 78:734-40. [PMID: 16628589 DOI: 10.1002/jmv.20616] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
The hepatitis B virus (HBV) genotypes distribution and the core promoter (CP)/precore (PC) variability were evaluated by a line probe assay in 272 patients infected chronically enrolled consecutively in an area of the North-Eastern Italy. Seven out of the eight genotypes were detected. Italian subjects (83% of the sample) were infected mainly by genotype D (73%) and A (26%); genotype F, and genotype H, were detected only in one subject. In foreigners, the genotype distribution reflected the distribution described for the areas of origin, that is, in Asia genotypes B, C, and D; in Africa genotypes A and E. CP and PC variants prevalence rates were 51% and 60%, respectively, and were significantly higher in Italian patients, probably in relation to their older age. In the analysis restricted to genotypes A and D, PC wild type was linked strongly to genotype A (OR = 4.08, 95% CI = 3.07-5.43, P < 0.0001). In genotype A-infected patients, only e seroconversion was associated significantly with CP variants. In genotype D-infected subjects, CP variants were linked significantly to older age and to a higher e seroconversion rate, while PC variants also showed a strong relationship with an ALT lower activity and a lower viral load. In multivariate analysis, HBeAg positivity was associated strongly and independently with younger age, genotype A and CP wild type. Independent determinants of higher viral loads were recognized by increasing age, in male gender and concomitant presence of HBeAg and the CP wild type virus.
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Affiliation(s)
- Gianna Dal Molin
- Department of Public Medicine Sciences, UCO Hygiene and Preventive Medicine, University of Trieste, and IRCCS Burlo Garofolo, Trieste, Italy
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Lin CL, Kao JH, Chen BF, Chen PJ, Lai MY, Chen DS. Application of hepatitis B virus genotyping and phylogenetic analysis in intrafamilial transmission of hepatitis B virus. Clin Infect Dis 2005; 41:1576-81. [PMID: 16267729 DOI: 10.1086/497837] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2005] [Accepted: 07/29/2005] [Indexed: 02/06/2023] Open
Abstract
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.
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Affiliation(s)
- Chih-Lin Lin
- Department of Gastroenterology, Taipei City Hospital, Taipei, Taiwan
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Thuy LTT, Ryo H, Van Phung L, Furitsu K, Nomura T. Distribution of genotype/subtype and mutational spectra of the surface gene of hepatitis B virus circulating in Hanoi, Vietnam. J Med Virol 2005; 76:161-9. [PMID: 15834887 DOI: 10.1002/jmv.20337] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
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.
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Affiliation(s)
- Le Thi Thanh Thuy
- Department of Radiation Biology and Medical Genetics, Graduate School of Medicine, Osaka University, Suita, Japan
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Su WP, Wen CC, Hsiung CA, Su IJ, Cheng AL, Chang MC, Tsao CJ, Kao WY, Uen WC, Hsu C, Hsu CH, Lu YS, Tien HF, Chao TY, Chen LT, Whang-Peng J, Chen PJ. Long-term hepatic consequences of chemotherapy-related HBV reactivation in lymphoma patients. World J Gastroenterol 2005; 11:5283-8. [PMID: 16149133 PMCID: PMC4622796 DOI: 10.3748/wjg.v11.i34.5283] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
AIM: To investigate the long-term consequences of chemotherapy-related HBV reactivation in patients with lymphoma.
METHODS: This study was based on the database of published prospective study evaluating HBV reactivation in HBV lymphoma patients during chemotherapy. Deteriorated liver reserve (DLR) was defined as development of either one of the following conditions during follow-up: (1) newly onset parenchyma liver disease, splenomegaly or ascites without evidence of lymphoma involvement; (2) decrease of the ratio (albumin/globulin ratio) to less than 0.8 or increase of the ratio of INR of prothrombin time to larger than 1.2 without evidence of malnutrition or infection. Liver cirrhosis was diagnosed by imaging studies.
RESULTS: A total of 49 patients were included. The median follow-up was 6.2 years (range, 3.9-8.1 years). There were 31 patients with and 18 patients without HBV reactivation. Although there was no difference of overall survival (OS) and chemotherapy response rate between the two groups, DLR developed more frequently in patients with HBV reactivation (48.4% vs 16.7%; P = 0.0342). Among the HBV reactivators, HBV genotype C was associated with a higher risk of developing DLR (P = 0.0768) and liver cirrhosis (P = 0.003). Four of five patients with sustained high titer of HBV DNA and two of three patients with multiple HBV reactivation developed DLR. Further, patients with a sustained high titer of HBV DNA had the shortest OS among the HBV reactivators (P = 0.0000). No patients in the non-HBV reactivation group developed hepatic failure or liver cirrhosis.
CONCLUSION: Chemotherapy-related HBV reactivation is associated with the long-term effect of deterioration of hepatic function.
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Affiliation(s)
- Wen-Pin Su
- Department of Oncology, National Taiwan University Hospital, No. 7, Chung-Shan South Road, Taipei 10016, Taiwan, China
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Echevarría JM, Avellón A, Magnius LO. Molecular epidemiology of hepatitis B virus in Spain: identification of viral genotypes and prediction of antigenic subtypes by limited sequencing. J Med Virol 2005; 76:176-84. [PMID: 15834869 DOI: 10.1002/jmv.20341] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
The hepatitis B virus (HBV) genotypes were studied by a line probe assay (LiPA) and by direct sequencing of a 339 nucleotide fragment from the S region of the viral genome in samples from 269 carriers living in Spain, either native to Spain (231) or immigrants from Africa, Asia, and Eastern Europe (38). The sequences were also used to predict the HBV surface antigen (HBsAg) subtype on the basis of the amino acids specified at selected positions of the HBsAg molecule. Agreement between the two genotyping methods was found in most cases (98.1%) and a HBV genotype could be assigned to all samples. The viral groups D/ayw2 (30.1%), D/ayw3 (28.6%), and A/adw2 (21.2%) were prevalent, with an additional participation of the groups D/ayw4 (4.8%), F/adw4q- (1.9%), A/ayw1 (1.9%), and D/adw3 (0.7%), all of them present among the autochthonous carriers. Strains from genotypes B and C were found exclusively among Chinese immigrants. Genotype E strains were found in immigrants from Central Africa and in one patient native of Spain. Point mutations leading to amino acid changes of residues involved in the expression of the HBsAg subtype determinants were found in 12 samples (4.5%). Some mutations would predict the putative novel genotype-subtype associations A/adw4q+, A/ayr, D/ayr, and E/ayw1, while others would suggest the loss of subtype-specific determinants. The finding of HBV strains characteristic for Africa among the autochthonous carriers confirms the emergence of African HBV strains in Spain.
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Affiliation(s)
- José M Echevarría
- Service of Diagnostic Microbiology, National Centre of Microbiology, Instituto de Salud Carlos III, Madrid, Spain.
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Kramvis A, Kew M, François G. Hepatitis B virus genotypes. Vaccine 2005; 23:2409-23. [PMID: 15752827 DOI: 10.1016/j.vaccine.2004.10.045] [Citation(s) in RCA: 255] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2004] [Revised: 09/27/2004] [Accepted: 10/14/2004] [Indexed: 12/17/2022]
Abstract
Eight genotypes of hepatitis B virus (A-H) are currently recognized, and subgenotypes have recently been described in four of these genotypes (A, B, C and F). The genotypes show a distinct geographical distribution between and even within regions, and are proving to be an invaluable tool in tracing the molecular evolution and patterns and modes of spread of hepatitis B virus. Structural and functional differences between genotypes can influence the severity, course and likelihood of complications, and response to treatment of hepatitis B virus infection and possibly vaccination against the virus. Although the number of studies on these genotypes has increased dramatically during recent years, much remains to be learnt about their full implications.
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Affiliation(s)
- Anna Kramvis
- MRC/University Molecular Hepatology Research Unit, Department of Medicine, University of the Witwatersrand Medical School, 7 York Road, Parktown, 2193 Johannesburg, South Africa.
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Ni YH, Chang MH, Wang KJ, Hsu HY, Chen HL, Kao JH, Yeh SH, Jeng YM, Tsai KS, Chen DS. Clinical relevance of hepatitis B virus genotype in children with chronic infection and hepatocellular carcinoma. Gastroenterology 2004; 127:1733-8. [PMID: 15578511 DOI: 10.1053/j.gastro.2004.09.048] [Citation(s) in RCA: 148] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
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.
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Affiliation(s)
- Yen-Hsuan Ni
- Department of Pediatrics, College of Medicine, National Taiwan University, Taipei 100. Taiwan
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Lam W, Li Y, Liou JY, Dutschman GE, Cheng YC. Reverse transcriptase activity of hepatitis B virus (HBV) DNA polymerase within core capsid: interaction with deoxynucleoside triphosphates and anti-HBV L-deoxynucleoside analog triphosphates. Mol Pharmacol 2004; 65:400-6. [PMID: 14742682 DOI: 10.1124/mol.65.2.400] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The use of L(-)SddC [beta-L-2',3'-dideoxy-3'-thiacytidine (lamivudine, 3TC)] for the treatment of Herpes B virus (HBV) infection is hindered by the emergence of drug-resistance associated with the L526M, L550V, and L526M/M550V mutations of the viral DNA polymerase (DP). The interactions of the anti-HBV compounds 2',3'-dideoxy-2',3'-didehydro-beta-L(-)-5-fluorode-oxycytidine and 2'-fluoro-5-methyl-beta-L-arabinofuranosyluracil triphosphate with HBV DP and its L(-)SddC-associated mutants have not been studied. The e antigen-negative variant of HBV associated with the G1896A mutation in the precore region has a high prevalence. Its effect on HBV DP is unclear. Because HBV DNA synthesis occurs in the nucleocapsid, we examined the kinetics of the reverse transcriptase activity from wild-type (wt) and mutated DPs with the wt or G1896A-mutated RNA template in the nucleocapsid. The effects of this template mutation on the activities of these L-nucleoside triphosphates were also examined. Results indicated that these DP mutations increased the Km values of deoxy-NTPs and decreased the efficiencies (Vmax/Km) of DPs. The additional L526M mutation increased the efficiency of the M550V-mutated DP but no more than that of the L526M-mutated DP. The G1896A mutation had impacts on the interactions between different DPs and deoxy-NTPs, except dCTP. It also had different impacts on the actions of the L-nucleoside triphosphates toward DPs. The L526M and M550V mutations caused a greater decrease in the Vmax using the wt RNA template compared with the G1896A-mutated template. The L526M, M550V, and L526M/M550V mutations caused varying degrees of resistance to the different M-nucleoside triphosphates.
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Affiliation(s)
- Wing Lam
- Department of Pharmacology, Yale University School of Medicine, New Haven, Connecticut 06520, USA
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Lusida MI, Sakugawa H, Nagano-Fujii M, Handajani R, Setiawan PB, Nidom CA, Ohgimoto S, Hotta H. Genotype and subtype analyses of hepatitis B virus (HBV) and possible co-infection of HBV and hepatitis C virus (HCV) or hepatitis D virus (HDV) in blood donors, patients with chronic liver disease and patients on hemodialysis in Surabaya, Indonesia. Microbiol Immunol 2004; 47:969-75. [PMID: 14695447 DOI: 10.1111/j.1348-0421.2003.tb03457.x] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Four subtypes (adw, adr, ayw, and ayr ) and eight genotypes (A to H) of the hepatitis B virus (HBV) have been identified. They appear to be associated with particular geographic distribution, ethnicity, and possibly clinical outcomes. In this study, hepatitis B surface antigen (HBsAg) subtyping and HBV genotyping were carried out on sera obtained from HBsAg-positive HBV carriers, including healthy blood donors; patients with acute hepatitis, chronic hepatitis, liver cirrhosis, and hepatocellular carcinoma; and patients on hemodialysis all located in Surabaya, Indonesia. We report here that all HBV isolates tested in Surabaya belonged to genotype B, with more than 90% of them being classified into subtype adw. Our results also revealed that prevalence of hepatitis C virus (HCV) co-infection among HBV carriers in Surabaya was approximately 10% for healthy blood donors and patients with chronic liver disease, and approximately 60% for patients on maintenance hemodialysis. Interestingly, HBsAg titers were lower in HBV carriers with HCV co-infection than in those without HCV co-infection. We also found that prevalence of hepatitis D virus (HDV) co-infection was < 0.5% among HBV carriers in Surabaya.
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Affiliation(s)
- Maria I Lusida
- Department of Microbiology, Faculty of Medicine & Dr. Soetomo Hospital, Surabaya, Indonesia
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Liu CJ, Chen PJ, Lai MY, Kao JH, Chen DS. Evolution of precore/core promoter mutations in hepatitis B carriers with hepatitis B e antigen seroreversion. J Med Virol 2004; 74:237-45. [PMID: 15332272 DOI: 10.1002/jmv.20176] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The evolution of precore stop codon mutation (A1896) and dinucleotide mutation (T1762/A1764) in the basic core promoter (BCP) of hepatitis B virus (HBV) genome during transient seroconversion and seroreversion of hepatitis B e antigen (HBeAg) remains unclarified. Five HBeAg-positive HBV carriers who experienced transient seroconversion followed by seroreversion of HBeAg (Group I, 3.3%) and 3 HBeAg-negative HBV carriers with documented reversion of HBeAg (Group II, 2.5%) in a prospective cohort of 272 patients with chronic hepatitis B were thus identified. The sequential changes at the precore nucleotide 1896 and BCP dinucleotide 1762/1764 were determined by polymerase chain reaction and direct sequencing. At enrollement, precore A1896 and BCP T1762/A1764 were noted in 4 (50%) and 1 (13%) of the eight patients. During a median follow-up period of 58 months (range: 31-76 months), 12 episodes of transient HBeAg seroconversion followed by seroreversion were encountered in Group I patients and 3 episodes of HBeAg seroreversion in Group II patients. Accompanying acute exacerbations were found in two-thirds of patients with either HBeAg seroconversion or seroreversion. Overall, precore nucleotide A1896 remained identical in 73% and 83% of the seroconversion and seroreversion events, respectively. BCP dinucleotide T1762/A1764 remained unchanged in 94% and 92% of the seroconversion and seroreversion events, respectively. At the end of follow-up, only one had both precore and BCP mutations. In conclusion, these data suggested that HBeAg seroreversion might be due to the lack of sustained precore and BCP mutations after HBeAg seroconversion. Although uncommon, HBeAg seroreversion can be associated with hepatitis exacerbation.
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Affiliation(s)
- Chun-Jen Liu
- Division of Gastroenterology, Department of Internal Medicine, National Taiwan University Hospital and National Taiwan University College of Medicine, Taipei, Taiwan
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30
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Abstract
Worldwide about 350 million people are chronic carriers of the hepatitis B virus (HBV). The infection can cause acute and chronic liver disease including cirrhosis and hepatocellular carcinoma (HCC). Hepatocellular injuries of HBV infection are predominantly immune-mediated, and the natural history of chronic infection can be divided into three phases based on virus-host interactions-namely, immune tolerance, immune clearance, and viral integration phases. Four serotypes (adw, ayw, adr, and ayr) and seven genotypes (A to G) of HBV have been identified, and they show some distinct geographic distributions. The HBV genotypes may have clinical relevance and are currently under investigation. On the basis of disease burden and the availability of safe and effective vaccines, the WHO recommended that by the end of the 20th century hepatitis B vaccine be incorporated into routine infant and childhood immunisation programmes for all countries. The efficacy of universal immunisation has been shown in different countries, with striking reductions of the prevalence of HBV carriage in children. Most important, hepatitis B vaccination can protect children against HCC and fulminant hepatitis, as has been shown in Taiwan. Nevertheless, the implementation of worldwide vaccination against HBV requires greater effort to overcome the social and economic hurdles. Safe and effective antiviral treatments are available but are still far from ideal, a situation that, hopefully, will be improved soon. With hepatitis B immunisation, the global control of HBV infection is possible by the end of the first half of 21st century.
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Affiliation(s)
- Jia-Horng Kao
- Graduate Institute of Clinical Medicine, National Taiwan University College of Medicine and National Taiwan University Hospital, Taipei, Taiwan
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31
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Abstract
Hepatitis B virus (HBV) infection is a global health problem and the clinical outcome of chronic HBV infection depends on the frequency and severity of hepatitis flares in the immune clearance phase. Currently, four subtypes and seven genotypes of HBV are identified and most have specific geographic distributions. The impact of HBV genotypes on the clinical outcome of chronic HBV infection has been partially clarified. In Taiwan, genotype C is associated with more severe liver disease and genotype B is associated with the development of hepatocellular carcinoma (HCC) in young non-cirrhotic patients. In contrast, genotype B has a relatively good prognosis in Japan and China and is rarely associated with the development of HCC. Similarly, genotype D is associated with more severe liver disease than genotype A in India and may predict occurrence of HCC in young patients. Although superinfection of HBV on top of hepatitis B carriers occurs in Taiwan, it is rarely associated with acute exacerbations. As to the response to antiviral treatment, genotypes C and D are associated with a lower response rate to interferon therapy compared with genotypes B and A. In addition, the subtype adw is reported to be associated with a higher risk of lamivudine resistance than ayw. In HBV subtype adw-infected HCC patients, genotype B responds better to embolization therapy and has a lower rate of HCC recurrence than genotype C. In summary, pathogenic and therapeutic differences do exist among HBV genotypes and determining the genotype in patients with chronic HBV infection would help gain further information for etiologic, clinical, virologic and anthropologic investigations. Further studies to clarify the molecular virological factors that contribute to these differences are awaited.
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Affiliation(s)
- Jia-Horng Kao
- Graduate Institute of Clinical Medicine, National Taiwan University College of Medicine, 7 Chung-Shan South Road, Taipei 100, Taiwan.
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