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1.
J Clin Microbiol ; 43(4): 1594-9, 2005 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15814971

RESUMO

This study was performed to determine the factors for predicting the occurrence of acute exacerbation of hepatitis B virus infection in HBeAg-negative patients. Two hundred and sixteen patients with known times of HBeAg seroclearance were recruited. Liver biochemistry and virologic markers were monitored. Precore and core promoter mutations were determined by a line probe assay. The median age at HBeAg seroclearance was 34.5 years. The median follow-up duration was 26.4 months. Fifty-six (27.9%) patients had acute exacerbations. By Cox regression analysis, male gender, older age, and core promoter mutations at the time of HBeAg seroclearance were independently associated with the occurrence of acute exacerbation after HBeAg seroclearance (P = 0.025, 0.018, and 0.001, respectively). Fourteen (7.0%) patients had HBeAg seroreversion within a median follow-up period of 11.6 months after HBeAg seroclearance. By Cox regression analysis, older age at HBeAg seroclearance was independently associated with the chance of HBeAg seroreversion (P = 0.01). We concluded that male patients with core promoter mutations and delayed HBeAg seroclearance had a higher cumulative chance of acute exacerbation in the HBeAg-negative phase. Patients with delayed HBeAg seroclearance had a higher frequency of HBeAg seroreversion.


Assuntos
Antígenos E da Hepatite B/sangue , Vírus da Hepatite B/patogenicidade , Hepatite B Crônica/fisiopatologia , Doença Aguda , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , China , DNA Viral/sangue , Feminino , Antígenos do Núcleo do Vírus da Hepatite B/genética , Vírus da Hepatite B/genética , Vírus da Hepatite B/isolamento & purificação , Hepatite B Crônica/virologia , Humanos , Testes de Função Hepática , Masculino , Pessoa de Meia-Idade , Mutação , Valor Preditivo dos Testes , Regiões Promotoras Genéticas , Precursores de Proteínas/genética
2.
J Clin Microbiol ; 42(11): 5036-40, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15528692

RESUMO

The aims of this study were to compare chronic hepatitis B (CHB) patients with genotypes B and C for the probability of HBeAg seroconversion, hepatitis activity, and viral replication before and after HBeAg seroconversion and to compare the prevalence of core promoter and precore mutations. A total of 180 asymptomatic Chinese patients with CHB were monitored for a median of 53.8 months, and 38 patients with cirrhosis-related complications were studied. Hepatitis B virus (HBV) DNA levels were measured in 16 patients with HBeAg seroconversion at 3 months before, during, and 3 months after HBeAg seroconversion and in all patients at the last follow-up. Hepatitis B genotypes and core promoter and precore mutations were determined. Compared to patients with genotype C (n = 109), patients with subtype Ba (n = 69) had a higher rate of anti-HBe positivity on presentation (P = 0.05). HBeAg-positive patients with subtype Ba had a higher cumulative rate of HBeAg seroconversion than patients with genotype C (P = 0.02). However, there were no differences between the two groups with regard to the median HBV DNA levels before, during, and after HBeAg seroconversion; the probability of having persistently normal or elevated aminotransferase levels; and the median HBV DNA levels and liver biochemistry at the last follow-up. There was no difference in the prevalence of genotypes and core promoter and precore mutations between patients with and without cirrhosis-related complications. Though patients with subtype Ba had earlier HBeAg seroconversion, the liver biochemistry, HBV DNA levels in different phases of the disease, and the probability of development of cirrhosis-related complications were the same with genotypes Ba and C.


Assuntos
Antígenos E da Hepatite B/sangue , Vírus da Hepatite B/classificação , Vírus da Hepatite B/patogenicidade , Hepatite B Crônica/fisiopatologia , Cirrose Hepática/fisiopatologia , Replicação Viral , Adolescente , Adulto , Idoso , DNA Viral/sangue , Feminino , Genótipo , Vírus da Hepatite B/genética , Vírus da Hepatite B/isolamento & purificação , Hepatite B Crônica/virologia , Humanos , Fígado/enzimologia , Cirrose Hepática/virologia , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade
3.
J Clin Microbiol ; 42(10): 4882-4, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15472371

RESUMO

We report two Chinese patients in whom lamivudine treatment resulted in HBsAg seroclearance. One patient received lamivudine, and another patient received 12-week famciclovir treatment followed by lamivudine. Lamivudine was maintained after HBeAg seroconversion. These two patients lost HBsAg at 24 and 27 months (ages, 23 and 19.3 years, respectively) and developed measurable titer of anti-HBs after 65 and 71 months of therapy, respectively. The liver biochemistry was normal after HBeAg seroconversion. The serum hepatitis B virus (HBV) DNA levels were undetectable (<200 copies/ml) both at the time of HBeAg seroconversion and at the last follow-up. Liver biopsy of one patient showed nearly normal histology, with undetectable intrahepatic total HBV DNA and covalently closed circular DNA. In conclusion, lamivudine therapy can result in HBsAg seroclearance at an early age even though the phenomenon is rare.


Assuntos
Antivirais/uso terapêutico , Antígenos de Superfície da Hepatite B/sangue , Hepatite B Crônica/tratamento farmacológico , Lamivudina/uso terapêutico , Adulto , Vírus da Hepatite B/efeitos dos fármacos , Vírus da Hepatite B/isolamento & purificação , Hepatite B Crônica/virologia , Humanos , Masculino , Resultado do Tratamento
4.
J Hepatol ; 41(1): 119-25, 2004 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15246217

RESUMO

BACKGROUND/AIMS: We conducted a population study to document the prevalence of hepatitis B virus (HBV) genotypes in Hong Kong. METHODS: HBV genotypes, core promoter (CP) and precore mutations were determined in 776 asymptomatic patients. RESULTS: 92.6% patients had single genotype [B (32.5%), C (62.5%)]. 99.1% of genotype B was subtype Ba. Patients with age <50 years had a lower prevalence of genotype B than patients with age >51 years (32.5% vs. 41%, respectively, P=0.028). Compared to patients with genotype C, patients with genotype B had a higher cumulative rate (P=0.018) and younger age (40.1 vs. 34.2 years, respectively, P=0.018) of HBeAg seroconversion. There were no differences in the HBV DNA levels between patients with genotypes B and C, and with wild-type and mutants of CP and precore regions. By multivariate analysis, patients with genotype C and with CP mutations had higher alanine aminotransferase (ALT) levels. CONCLUSIONS: B and C were the two most common HBV genotypes in Hong Kong. The former had a higher chance of earlier HBeAg seroconversion and lower ALT levels. The prevalence of genotype B was lower in patients with age <50, probably related to influx of immigrants from China since 1949.


Assuntos
Vírus da Hepatite B/genética , Hepatite B Crônica/epidemiologia , Hepatite B Crônica/virologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Alanina Transaminase/sangue , Bilirrubina/sangue , Criança , Pré-Escolar , DNA Viral/sangue , Feminino , Genótipo , Anticorpos Anti-Hepatite B/sangue , Antígenos E da Hepatite B/genética , Hepatite B Crônica/imunologia , Hong Kong/epidemiologia , Humanos , Lactente , Fígado/metabolismo , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Mutação , Prevalência , Regiões Promotoras Genéticas/genética , Albumina Sérica
5.
Carcinogenesis ; 25(9): 1593-8, 2004 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15090469

RESUMO

The role of hepatitis B virus (HBV) genotypes, core promoter (CP) and precore mutants on hepatocellular carcinoma (HCC) is still controversial. We aimed to determine their role on the development and clinical features of HCC. HBV genotypes and CP/precore mutations were determined in 90 HCC patients and 180 matched control patients. In the 90 HCC patients, 22 (24.4%) and 68 (75.6%) had subtype Ba and genotype C, respectively. The prevalence of genotype C and CP mutations was significantly higher in HCC patients compared with controls (75.6 versus 57.8%, P = 0.004; 90.9 versus 74.8%, respectively, P = 0.007). Among carriers of genotype C, 91.8% of the HCC patients and 88.8% of controls had CP mutations. Among carriers of subtype Ba, HCC patients had a higher prevalence of CP mutations compared with controls (88.2 versus 54.5%, respectively, P = 0.02). By logistic regression analysis, the only factor associated with HCC was a mutation of the CP region (P = 0.032). There were no differences in the clinical features on presentation, the chance of receiving treatment and the cumulative survival rate for chemoembolization-treated patients between patients with subtype Ba and genotype C. There was too small a number of CP wild-type to do a similar comparison with CP mutants. In conclusion, there was a significantly higher prevalence of both genotype C and CP mutations in patients with HCC. The association between HBV genotype C and HCC was probably not genuine but was due to the high percentage of CP mutations in patients with genotype C.


Assuntos
Carcinoma Hepatocelular/virologia , Portador Sadio , Vírus da Hepatite B/genética , Hepatite B/complicações , Neoplasias Hepáticas/virologia , Mutação/genética , Regiões Promotoras Genéticas/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Feminino , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco
6.
J Hepatol ; 39(5): 850-5, 2003 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-14568270

RESUMO

BACKGROUND/AIMS: To study the outcome and the virologic profiles of severe hepatitis exacerbations due to YMDD mutants in lamivudine-treated patients. METHODS: Eighteen lamivudine-treated patients with severe hepatitis exacerbations due to YMDD mutants were recruited. Laboratory and clinical parameters were monitored. Viral genotypes and YMDD mutations were determined. RESULTS: None of the 18 patients had YMDD wild-type during exacerbations. Three (17%) and 15 (83%) patients had genotypes B and C, respectively. Elevated bilirubin levels and prolonged prothrombin time were found in 11 (61%) and six patients (33%) respectively. Three patients (17%) had adverse outcome with the development of ascites and/or encephalopathy. One of these patients required liver transplantation and one died. Both patients had evidence of cirrhosis before treatment and hepatitis B e antigen (HBeAg) seroreversion from anti-HBe positivity. The remaining 16 patients (89%) have no evidence of pre-existing cirrhosis. Thirty seven percent of patients had normal alanine aminotransferase levels at the last follow-up. The median HBV DNA level at the last follow-up was significantly lower than the pre-treatment level (P=0.009). CONCLUSIONS: Though the majority of patients with severe hepatitis exacerbations due to YMDD mutants had uneventful course, early liver transplantation should be considered in patients with pre-existing cirrhosis and HBeAg seroreversion.


Assuntos
Vírus da Hepatite B/genética , Hepatite B/fisiopatologia , Hepatite B/virologia , Lamivudina/uso terapêutico , Mutação , Inibidores da Transcriptase Reversa/uso terapêutico , Adulto , Alanina Transaminase/metabolismo , DNA Viral/metabolismo , Feminino , Genótipo , Hepatite B/tratamento farmacológico , Hepatite B/genética , Humanos , Masculino , Pessoa de Meia-Idade , Índice de Gravidade de Doença , Resultado do Tratamento
7.
Antivir Ther ; 8(6): 531-4, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-14760886

RESUMO

To date, there have been no studies examining the role of hepatitis B virus (HBV) genotypes on the response to lamivudine therapy and the development of YMDD mutations. The present study aimed at determining any differences in the antiviral response and risk of YMDD mutations between lamivudine-treated patients with HBV genotype B and genotype C. Eighty-two patients receiving lamivudine were recruited. HBV genotypes at baseline and YMDD mutations at week 52 were determined by line probe assays (LiPA). HBV DNA levels were determined by the Cobas Amplicor HBV Monitor Test. Seventeen (20.7%) and sixty-four (78%) patients had single genotypes of B and C, respectively. At both week 24 and 52 there were no differences in the median reduction of HBV DNA levels (median 4 logs drop), the median reduction of alanine aminotransferase (ALT) levels, and the proportion with normalization of ALT [8/8 (100%) vs 26/37 (70.3%), P=0.19] between patients with genotypes B and C. The rate of HBeAg seroconversion [3/17 (17.6%) vs 6/64 (9.4%), P=0.39] and the chance of YMDD mutation development [3/17 (17.6%) vs 12/64 (18.8%), P=1.0] at week 52 were also similar between patients with genotype B and C, respectively. In conclusion, there was no difference in the antiviral response and the rate of development of YMDD mutations in Chinese patients with genotype B and C after 1 year of lamivudine. Determination of HBV genotypes before lamivudine therapy was probably not an important pretreatment investigation to predict antiviral responses in Chinese patients.


Assuntos
Antivirais/uso terapêutico , Vírus da Hepatite B/classificação , Hepatite B/tratamento farmacológico , Lamivudina/uso terapêutico , Adolescente , Adulto , Alanina Transaminase/sangue , Farmacorresistência Viral , Feminino , Produtos do Gene pol/genética , Genótipo , Hepatite B/virologia , Vírus da Hepatite B/genética , Humanos , Masculino , Pessoa de Meia-Idade , Mutação
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