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1.
J Viral Hepat ; 25(8): 886-893, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29532589

RESUMO

HBeAg seroconversion marks an important spontaneous change and treatment end-point for HBeAg-positive patients and is a pre-requisite for HBsAg loss or functional cure. In this retrospective analysis, we aimed to identify predictors of seroconversion using serum quantitative HBsAg and HBcrAg, in HBeAg-positive patients treated with nucleos(t)ide analogues (NA). Data and samples from 118 HBeAg-positive adults (genotypes A-G) started on NA between Jan 2005 and Sept 2016 were retrospectively analysed at several time-points. The predictive power of on-treatment levels of HBsAg and HBcrAg was determined using receiver operating curve (ROC) analysis and cut-off values determined by maximized Youden's index. About 36.4% of patients achieved HBeAg seroconversion after a median of 39 months' treatment. On treatment kinetics of HBV DNA, HBsAg and HBcrAg differed between HBeAg seroconverters and nonseroconverters. A combination of HBsAg and HBcrAg had the greatest predictive value for HBeAg seroconversion: at 6 months, HBsAg of 3.9 log10  IU/mL and HBcrAg of 5.7 log10 U/mL had a sensitivity of 71.4%, specificity of 79.5%, positive predictive value (PPV) of 65.2% and negative predictive value (NPV) of 83.8%, with AUROC of 0.769 (0.668, 0.869; 95%CI), and at 12 months, HBsAg 3.8 log10  IU/mL and HBcrAg 5.5 log10 U/mL had a sensitivity of 73.7%, specificity of 79.5%, PPV of 63.6% and NPV of 86.1%, with AUROC 0.807 (0.713, 0.901; 95% CI). In conclusion, our results may be used to identify patients who are unlikely to achieve treatment end-points, which will be important as the future management of chronic hepatitis B looks to therapies that offer functional cure.


Assuntos
Antivirais/uso terapêutico , Técnicas de Apoio para a Decisão , Antígenos do Núcleo do Vírus da Hepatite B/sangue , Antígenos de Superfície da Hepatite B/sangue , Antígenos E da Hepatite B/sangue , Hepatite B Crônica/tratamento farmacológico , Soroconversão , Adolescente , Adulto , Idoso , DNA Viral/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Nucleosídeos/uso terapêutico , Nucleotídeos/uso terapêutico , Curva ROC , Estudos Retrospectivos , Sensibilidade e Especificidade , Resultado do Tratamento , Adulto Jovem
2.
J Viral Hepat ; 25(10): 1139-1150, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29660209

RESUMO

Tubular renal toxicity is a side-effect of long-term therapy with nucleos(t)ide analogue(s) (NA) in chronic hepatitis B (CHB). There are no established surrogate markers in plasma of early NA-related toxicity. Neutrophil gelatinase-associated lipocalin (NGAL) is a protein produced by tubular cells following renal damage. We aimed therefore to retrospectively compare conventional renal markers (estimated glomerular filtration rates (eGFR) and urinary protein/creatinine ratio uPCR) with a sensitive biomarker (NGAL) in CHB patients on long-term NA therapy and assess the ability of new markers to predict NA-related renal toxicity (new onset of nonalbumin proteinuria). A total of 192 naïve CHB patients (median age 41 years, 78% males, 25% HBeAg+, 35% cirrhosis) were NA treated for at least 5 years (median 8.34 years, range 5.54-11.1 years). The eGFR and uPCR were compared at baseline and last clinical visit with serum NGAL concentrations measured by ELISA at same time-points and assessed according to the presence/absence of nonalbumin proteinuria at last visit. While baseline and last visit eGFR were similar (median:78 vs 84 mL/min), serum NGAL concentrations increased during therapy (median:9.4 vs 16.4 ng/mL, P < .05). The proportion of patients with proteinuria (uPCR > 15) increased between baseline and last visit (4.6% vs 21.4%, P < .05), with 30 (16%) patients having de novo nonalbumin proteinuria at last visit. High baseline NGAL concentrations were exclusive to patients with de novo nonalbumin proteinuria (median:31.7 vs 7.8 ng/mL, P < .01) and baseline NGAL levels >25 mg/mL were predictive of nonalbumin proteinuria at last visit (AUROC = 0.813). In conclusion, serum NGAL can act as a surrogate marker of early renal injury (de novo nonalbumin proteinuria) in CHB on long-term NA therapy.


Assuntos
Antivirais/efeitos adversos , Hepatite B Crônica/tratamento farmacológico , Lipocalina-2/sangue , Insuficiência Renal/diagnóstico , Adulto , Fatores Etários , Idoso , Antivirais/uso terapêutico , Biomarcadores/sangue , Biomarcadores/urina , Creatinina/sangue , Diagnóstico Precoce , Feminino , Taxa de Filtração Glomerular , Humanos , Masculino , Pessoa de Meia-Idade , Nucleosídeos/efeitos adversos , Nucleosídeos/uso terapêutico , Nucleotídeos/efeitos adversos , Nucleotídeos/uso terapêutico , Proteinúria/urina , Curva ROC , Insuficiência Renal/etiologia , Estudos Retrospectivos , Adulto Jovem
3.
J Viral Hepat ; 22(11): 882-9, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25847572

RESUMO

The efficacy of treatment for hepatitis C genotype 1 infection has significantly improved with the introduction of first-generation protease inhibitors. However, there remains a need for effective treatments for patients infected with other genotypes, for nonresponders and patients unsuitable for interferon. Sofosbuvir is the first nucleotide polymerase inhibitor with pan-genotypic activity. Sofosbuvir-based regimens have resulted in >90% sustained virological response across treatment-naïve genotype 1-6 patients in five phase III clinical trials of sofosbuvir administered with ribavirin or pegylated interferon and ribavirin. This analysis evaluates the cost-effectiveness of sofosbuvir within the current licensed indication, for genotype 1-6 in the UK. A Markov model followed a cohort of 10 000 patients over lifetime, with approximately 20% initiating treatment for compensated cirrhosis. Sofosbuvir-regimens were compared to telaprevir, boceprevir, pegylated interferon and ribavirin, or no treatment. Costs and outcomes were discounted at 3.5%. The cost perspective utilized costs applicable to the National Health Service in the UK. Sofosbuvir proved to be cost-effective in most patient populations with incremental cost-effectiveness ratios (ICERs) at £11 836/QALY and £7292/QALY against telaprevir and boceprevir, respectively. In genotype 3, sofosbuvir had a weighted ICER of £18 761/QALY. Sofosbuvir-based regimens are a cost-effective option for the majority of hepatitis C-infected patients in the United Kingdom although the incremental cost-effectiveness varies by genotype and regimen. Sofosbuvir and ribavirin is an alternative regimen for patients unsuitable for interferon.


Assuntos
Antivirais/administração & dosagem , Antivirais/economia , Custos de Cuidados de Saúde , Hepatite C Crônica/tratamento farmacológico , Sofosbuvir/administração & dosagem , Sofosbuvir/economia , Análise Custo-Benefício , Humanos , Reino Unido
4.
J Viral Hepat ; 21(5): 377-80, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24131506

RESUMO

The population of patients with chronic hepatitis C viral infection is ageing; however, elderly, hepatitis C-infected patients are understudied and less frequently treated. This subanalysis of data from the multinational PROPHESYS study examined associations between age (≤65 vs >65 years), on-treatment virological response and sustained virological response (SVR) in patients treated with peginterferon alfa-2a (40KD)/ribavirin in accordance with local licences. PROPHESYS comprised three cohorts studied in 19 countries according to country-specific legal and regulatory requirements. This subanalysis includes treatment-naive HCV mono-infected patients assigned to receive peginterferon alfa-2a (40KD)/ribavirin, with 6276 individuals aged ≤65 years and 349 aged >65 years. Rapid virological response (RVR) rates by Week 4 were consistently lower in older genotype (G) 1 (21.6% vs 27.2% in younger patients), G2 (80.7% vs 85.1%) and G3 (60.0% vs 74.2%) patients. SVR rates were significantly lower (29.8% vs 43.0%) and relapse rates significantly higher (43.1% vs 26.7%) in older G1 patients (P = 0.0002 vs ≤65 years). In contrast, SVR and relapse rates were similar in G2 and G3 patients regardless of age. The positive predictive value of RVR for SVR was comparable in older and younger G1 patients (66.7% vs 68.6%, respectively) and higher in older G2 (80.7% vs 75.6%) and G3 (77.8% vs 66.8%) patients. Virological response rates are generally lower in elderly CHC patients, and RVR is a reliable positive predictor of SVR in patients >65 years.


Assuntos
Antivirais/uso terapêutico , Hepacivirus/isolamento & purificação , Hepatite C Crônica/tratamento farmacológico , Hepatite C Crônica/virologia , Interferon-alfa/uso terapêutico , Polietilenoglicóis/uso terapêutico , Ribavirina/uso terapêutico , Carga Viral , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Proteínas Recombinantes/uso terapêutico , Recidiva , Resultado do Tratamento
5.
J Viral Hepat ; 19 Suppl 2: 1-26, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22404758

RESUMO

The aim of this study is to review clinical trial data on the newly approved protease inhibitors boceprevir and telaprevir to develop consensus recommendations on the optimal use of these agents for the treatment of patients with chronic hepatitis C virus (HCV) infection. An expert panel of seven leading authorities in viral hepatitis was convened to establish and disseminate a practical guide on best practices for incorporating boceprevir and telaprevir into therapy for HCV infection in both treatment-naive and treatment-experienced patients. The topics covered include selecting candidates for boceprevir- or telaprevir-based treatments, predictors of response and early viral kinetics, response-guided therapy approaches, on-treatment management strategies to optimize the likelihood of response and minimize the risk of drug resistance, management of adverse effects during therapy and key considerations for special populations. The expert panel incorporated the best available clinical evidence into recommendations on how boceprevir and telaprevir should be used in the clinical setting. They indicated how treatment regimens may differ according to the baseline factors, such as presence of cirrhosis and when therapy may need to be modified or stopped altogether because of adverse events or poor virologic response. This practical guide will serve as a valuable resource for clinicians embarking on the new treatment paradigm of boceprevir or telaprevir in combination with peginterferon/ribavirin for chronic genotype 1 HCV infection.


Assuntos
Antivirais/uso terapêutico , Hepacivirus , Hepatite C Crônica/tratamento farmacológico , Oligopeptídeos/uso terapêutico , Prolina/análogos & derivados , Inibidores de Proteases/uso terapêutico , Ensaios Clínicos como Assunto , Quimioterapia Combinada , Feminino , Hepatite C Crônica/virologia , Humanos , Masculino , Guias de Prática Clínica como Assunto , Prolina/uso terapêutico , Viremia/tratamento farmacológico , Viremia/virologia
6.
J Viral Hepat ; 18 Suppl 1: 1-16, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21824223

RESUMO

Worldwide, the hepatitis B virus (HBV) and the hepatitis C virus (HCV) cause, respectively, 600,000 and 350,000 deaths each year. Viral hepatitis is the leading cause of cirrhosis and liver cancer, which in turn ranks as the third cause of cancer death worldwide. Within the WHO European region, approximately 14 million people are chronically infected with HBV, and nine million people are chronically infected with HCV. Lack of reliable epidemiological data on HBV and HCV is one of the biggest hurdles to advancing policy. Risk groups such as migrants and injecting drug users (IDU) tend to be under-represented in existing prevalence studies; thus, targeted surveillance is urgently needed to correctly estimate the burden of HBV and HCV. The most effective means of prevention against HBV is vaccination, and most European Union (EU) countries have universal vaccination programmes. For both HBV and HCV, screening of individuals who present a high risk of contracting the virus is critical given the asymptomatic, and thereby silent, nature of disease. Screening of migrants and IDUs has been shown to be effective and potentially cost-effective. There have been significant advances in the treatment of HCV and HBV in recent years, but health care professionals remain poorly aware of treatment options. Greater professional training is needed on the management of hepatitis including the treatment of liver cancer to encourage adherence to guidelines and offer patients the best possible outcomes. Viral hepatitis knows no borders. EU Member States, guided by the EU, need to work in a concerted manner to implement lasting, effective policies and programmes and make tackling viral hepatitis a public health priority.


Assuntos
Hepatite B/epidemiologia , Hepatite B/prevenção & controle , Hepatite C/epidemiologia , Hepatite C/prevenção & controle , Europa (Continente)/epidemiologia , Hepatite B/complicações , Hepatite B/mortalidade , Hepatite C/complicações , Hepatite C/mortalidade , Humanos , Cirrose Hepática/epidemiologia , Cirrose Hepática/prevenção & controle , Cirrose Hepática/virologia , Neoplasias Hepáticas/epidemiologia , Neoplasias Hepáticas/prevenção & controle , Neoplasias Hepáticas/virologia , Programas de Rastreamento/métodos , Vigilância da População/métodos , Vacinação/estatística & dados numéricos
7.
J Exp Med ; 193(7): 847-54, 2001 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-11283157

RESUMO

Using patient data from a unique single source outbreak of hepatitis B virus (HBV) infection, we have characterized the kinetics of acute HBV infection by monitoring viral turnover in the serum during the late incubation and clinical phases of the disease in humans. HBV replicates rapidly with minimally estimated doubling times ranging between 2.2 and 5.8 d (mean 3.7 +/- 1.5 d). After a peak viral load in serum of nearly 10(10) HBV DNA copies/ml is attained, clearance of HBV DNA follows a two or three phase decay pattern with an initial rapid decline characterized by mean half-life (t(1/2)) of 3.7 +/- 1.2 d, similar to the t(1/2) observed in the noncytolytic clearance of covalently closed circular DNA for other hepadnaviruses. The final phase of virion clearance occurs at a variable rate (t(1/2) of 4.8 to 284 d) and may relate to the rate of loss of infected hepatocytes. Free virus has a mean t(1/2) of at most 1.2 +/- 0.6 d. We estimate a peak HBV production rate of at least 10(13) virions/day and a maximum production rate of an infected hepatocyte of 200-1,000 virions/day, on average. At this peak rate of virion production we estimate that every possible single and most double mutations would be created each day.


Assuntos
DNA Viral/sangue , Vírus da Hepatite B/crescimento & desenvolvimento , Hepatite B/sangue , Doença Aguda , DNA Circular/metabolismo , Surtos de Doenças , Meia-Vida , Hepatite B/epidemiologia , Humanos , Cinética , Fígado/virologia , Vírion/crescimento & desenvolvimento
8.
J Viral Hepat ; 17(7): 469-74, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19780940

RESUMO

In chronic hepatitis C, transient elastography (TE) accurately identifies cirrhosis, but its ability to assess significant fibrosis (Metavir > or = F2) is variable. Constitutional and liver disease-related factors may influence TE and here we examined the variables associated with differences. Three hundred consecutive hepatitis C virus (HCV)-RNA positive patients had biochemical tests, TE and a biopsy performed on the same day. The Dale model was used to identify the variables associated with discordance between biopsy and elastography results. In 97 patients (34.2%), TE and histological assessment were discordant. Seventy-six of 286 (26.6%) had stage > or =F2 and TE < 7.1 kPa (false negative); 21 of 286 (7.3%) had stage or = 7.1 kPa (false positive). No patient with discordant results had cirrhosis. By Dale model, aspartate aminotransferase (AST) was found to be the unique variable significantly related (P = 0.046) with discordance between biopsy and TE. Discordance rate was 43.4% (82 patients) with AST < 1.5 x UNL vs 25.8% (25 patients) with AST > or = 1.5 x UNL (P = 0.004). False negative rate was 43.4 (82 patients) with AST < 1.5 x UNL vs 17.1% (13 patients) with AST > or = 1.5 x UNL (P < 0.001). Areas under the receiver operating characteristic (AUROC) for F > or = 2, according to AST < 1.5 x UNL vs > or = 1.5 x UNL were 0.738 (95% CI: 0.683-0.812) and 0.854(95% CI: 0.754-0.907). Transient elastography is not adequate on its own to rule out or to rule in significant fibrosis, as it is influenced by major variations in biochemical activity of liver disease. Liver stiffness, at low levels of AST, can underestimate fibrosis.


Assuntos
Biópsia , Técnicas de Imagem por Elasticidade , Hepatite C Crônica/complicações , Cirrose Hepática/diagnóstico , Cirrose Hepática/patologia , Índice de Gravidade de Doença , Adulto , Erros de Diagnóstico , Feminino , Histocitoquímica , Humanos , Masculino , Pessoa de Meia-Idade , Curva ROC , Transaminases/sangue
9.
J Viral Hepat ; 17(8): 546-54, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19874477

RESUMO

Historically, liver biopsy (LB) was the sole method to evaluate the severity of hepatic fibrosis in patients with chronic hepatitis C infection. However, LB is expensive and associated with a risk of severe complications. Therefore, noninvasive tests have been developed to assess the severity of liver fibrosis. The accuracy of Fibroscan (FS) and King's score (KS) was evaluated individually and in combination using liver histology as the reference standard. One hundred and eighty-seven patients were identified who had undergone a biopsy with a diagnosis of chronic hepatitis C virus (HCV) mono-infection (HCV RNA-positive by RT-PCR), attending King's College Hospital (n = 88) or the Royal Free Hospital (n = 99) (London) between May 2006 and December 2007. Liver fibrosis was scored using the Ishak method; significant fibrosis was defined as Ishak fibrosis stage F3-F6, and cirrhosis defined as Ishak fibrosis F5-F6. The diagnostic accuracy of each test was assessed by area under receiver operator characteristic curves (AUROC). Median age was 49 years (43-54) and 115 (61%) were male. The AUROC for FS, KS and FS + KS for the diagnosis of Ishak F3-F6 were 0.83, 0.82 and 0.85, respectively and for the diagnosis of cirrhosis (>or=F5) were 0.96, 0.89 and 0.93, respectively. The negative predictive values for the diagnosis of cirrhosis using the optimal cut-off results for fibrsocan (10.05 kPa), KS (24.3) and the two combined (26.1) were 98%, 91% and 94%, respectively. The noninvasive markers and, particularly, FS were effective tests for the prediction of cirrhosis in chronic hepatitis C. Both KS and FS also had clinical utility for the prediction of Ishak fibrosis stages F3-F6.


Assuntos
Técnicas de Imagem por Elasticidade/métodos , Hepacivirus/crescimento & desenvolvimento , Hepatite C Crônica/patologia , Cirrose Hepática/patologia , Adulto , Alanina Transaminase/sangue , Fosfatase Alcalina/sangue , Área Sob a Curva , Aspartato Aminotransferases/sangue , Bilirrubina/sangue , Técnicas de Imagem por Elasticidade/normas , Feminino , Hepatite C Crônica/diagnóstico , Hepatite C Crônica/virologia , Histocitoquímica , Humanos , Cirrose Hepática/diagnóstico , Cirrose Hepática/virologia , Masculino , Pessoa de Meia-Idade , Contagem de Plaquetas , Valor Preditivo dos Testes , Estudos Prospectivos , Curva ROC , gama-Glutamiltransferase/sangue
11.
J Viral Hepat ; 16(11): 769-74, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19709363

RESUMO

Liver biopsy is frequently required in HBeAg-negative disease to determine the stage of fibrosis. It can be difficult to distinguish cohorts with undetectable HBeAg who may have varying degrees of fibrosis due to different stages of disease. We have assessed the utility of transient elastography (TE) to evaluate differences in HBeAg-negative patients. A total of 220 HBsAg-positive individuals were studied: 125 (group 1) had an inactive HBsAg carrier state and 95 (group 2) were HBeAg-negative, anti-HBe-positive patients with persistently or intermittent elevation of alanine aminotransferase (ALT) and/or HBV DNA >10(5) copies/mL. Mean stiffness was 4.83 +/- 1.2 kPa in group 1 vs 8.53 +/- 6 kPa in group 2 (P < 0.001); statistically significant differences were also found between AST/ULN ALT/ULN ratios, HBV DNA in group 1 vs group 2, respectively (P < 0.001). In the multivariate analysis, the only variable independently associated with the stage of fibrosis was the stiffness. This study shows that mean hepatic stiffness by elastography is significantly lower in patients with inactive hepatitis B compared to those with HBeAg-negative disease. The procedure is a useful adjunct to diagnosis to confirm a clinical pattern of disease, and for more selective use of liver biopsy before considering antiviral therapy.


Assuntos
Portador Sadio/diagnóstico , Técnicas de Imagem por Elasticidade/métodos , Antígenos E da Hepatite B/sangue , Hepatite B/diagnóstico , Adulto , Idoso , Alanina Transaminase/sangue , Biópsia , Portador Sadio/imunologia , Portador Sadio/patologia , Portador Sadio/virologia , Estudos Transversais , Diagnóstico Diferencial , Feminino , Hepatite B/imunologia , Hepatite B/patologia , Hepatite B/virologia , Anticorpos Anti-Hepatite B/sangue , Antígenos de Superfície da Hepatite B/sangue , Antígenos E da Hepatite B/imunologia , Vírus da Hepatite B/imunologia , Vírus da Hepatite B/isolamento & purificação , Humanos , Fígado/patologia , Masculino , Pessoa de Meia-Idade , Adulto Jovem
12.
J Viral Hepat ; 15(12): 901-9, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19087227

RESUMO

The natural killer (NK) cell receptor, NKG2D is a member of the c-type lectin-activating receptor family. It is expressed by all NK cells and by a sub-population of CD8+ T cells. NKG2D engagement with its ligands directly activates NK cells and acts as a co-stimulator on CD8+ T cells. Recent reports, however, have demonstrated a role for NKG2D in direct T-cell activation in chronic inflammation. The aim of this study was to investigate the pattern of expression and the functional role of NKG2D on circulating and intrahepatic CD8+ T cells in chronic viral hepatitis. Peripheral blood lymphocytes and intrahepatic lymphocytes from 45 patients with chronic viral hepatitis (HBV and HCV) were studied. Phenotypic NKG2D expression and its functional ability to activate intrahepatic and circulating lymphocytes were analysed. Intrahepatic CD8+ T cells display increased NKG2D expression in chronic viral hepatitis in comparison with circulating CD8+ T cells. NKG2D co-stimulates intrahepatic CD8+ T cells and hepatitis B virus-specific CD8+ T cells. However, we could not demonstrate an ability to directly activate CD8+ T cells through the NKG2D signalling pathway alone. NKG2D is up-regulated on intrahepatic CD8+ T cells in type B and C chronic viral hepatitis; however, its function appears to be restricted to that of a co-stimulatory molecule.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Expressão Gênica , Hepatite Crônica/imunologia , Subfamília K de Receptores Semelhantes a Lectina de Células NK/genética , Subfamília K de Receptores Semelhantes a Lectina de Células NK/imunologia , Adulto , Linhagem Celular , Células Cultivadas , Feminino , Hepatite Crônica/virologia , Hepatite Viral Humana/imunologia , Hepatócitos/imunologia , Hepatócitos/virologia , Humanos , Interleucina-15/genética , Interleucina-15/metabolismo , Fígado/imunologia , Ativação Linfocitária , Masculino , Pessoa de Meia-Idade
13.
S Afr Med J ; 108(8b): 22-30, 2018 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-30182909

RESUMO

Hepatitis B virus vaccination, while effective in reducing incident chronic hepatitis B in endemic regions, will not have the desired impact on the rates of end-stage liver disease in chronically infected persons. A large reservoir of chronic infection remains and needs to be managed effectively. Over three decades, interferon alpha (IFNα), and nucleoside analogue therapies have reduced the morbidity and mortality associated with chronic hepatitis B by suppressing viral replication and retarding the progression to cirrhosis and the development of hepatocellular carcinoma (HCC). The preferential preservation of covalently closed circular (cccDNA) and capsid reverse transcriptase-cccDNA interactions during nucleoside analogue therapy currently prevent cure; the majority of patients require continuous maintenance suppressive therapy. In selected patients nucleoside analogues may be stopped. New targets for drug therapy need to be directed at inhibiting intracellular HBV replication, transcription and translation pathways to enhance the likelihood of a cure in the host. Such cures for chronic hepatitis B infection will require several synergistic therapies to achieve either complete eradication of replicative intermediates from the host (cure), or more probably, a functional cure defined as loss of hepatitis B surface antigen. Hampering such development is the lack of a proven serological surrogate for cccDNA to evaluate treatment efficacy. This review outlines the pathophysiology of the virus, the host immunological responses and current therapies. Understanding the interactions between HBV and the host remains fundamental to guide correct sequencing and combinations of treatment with either host or viral-targeting agents to achieve higher rates of cure.


Assuntos
Antivirais , Doença Hepática Terminal , Vírus da Hepatite B , Hepatite B Crônica , Antivirais/classificação , Antivirais/farmacologia , Doença Hepática Terminal/etiologia , Doença Hepática Terminal/prevenção & controle , Vírus da Hepatite B/efeitos dos fármacos , Vírus da Hepatite B/fisiologia , Hepatite B Crônica/complicações , Hepatite B Crônica/terapia , Humanos
14.
J Clin Invest ; 71(5): 1104-13, 1983 May.
Artigo em Inglês | MEDLINE | ID: mdl-6602149

RESUMO

It has been postulated that host immune defects are responsible for the development and persistence of the hepatitis B surface antigen (HBsAg) carrier state. The nature of these defects is unknown, but the absence of a readily detectable antibody response to HBsAg (anti-HBs) may be important. The synthesis of both anti-HBs and antibody to hepatitis B core antigen (anti-HBc) in cultures containing peripheral blood mononuclear cells from chronic HBsAg carriers and from control (antibody-positive) patients was measured in the presence of pokeweed mitogen. Similar amounts of polyclonal IgG and IgM were synthesized by cultures containing lymphocytes from chronic carriers and controls. Anti-HBc was detectable in lymphocyte supernatants from 2 of 20 controls and from 21 of 29 carriers. The presence of anti-HBc synthesis in vitro correlated with high serum titers of anti-HBc. In contrast, anti-HBs was detected in lymphocyte supernatants from 6 of 20 controls (predominantly in those who had high serum titers of anti-HBs) but in none of the supernatants from 29 HBsAg carriers. In order to identify the mechanisms for the lack of detectable anti-HBs synthesis by chronic HBsAg carrier lymphocytes, co-culture experiments were performed using T and B lymphocyte fractions that had been purified by affinity chromatography. B lymphocytes from carriers co-cultured with allogeneic irradiated ("helper") T lymphocytes from controls synthesized normal amounts of IgG, IgM, and anti-HBc but still did not synthesize detectable amounts of anti-HBs. In the converse experiments, B lymphocytes from controls were co-cultured with irradiated T lymphocytes from carriers. The T lymphocytes from 16 of 24 carriers augmented anti-HBs production by control B cells normally, the remaining eight did not. Finally, mixtures of control B cells and control irradiated T lymphocytes were co-cultured with T lymphocytes from chronic HBsAg carriers. 5 of 12 carriers demonstrated active suppression of anti-HBs production, and in three this suppression was specific, as IgG and IgM production remained normal. We conclude that chronic HBsAg carriers have a specific B lymphocyte defect in anti-HBs production. In addition, defects in the function of regulatory T lymphocytes may contribute to the absence of anti-HBs synthesis in some HBsAg carriers.


Assuntos
Anticorpos Antivirais/biossíntese , Anticorpos Anti-Hepatite B/biossíntese , Antígenos de Superfície da Hepatite B/imunologia , Vírus da Hepatite B/imunologia , Hepatite B/imunologia , Linfócitos/imunologia , Adulto , Linfócitos B/imunologia , Células Cultivadas , Doença Crônica , Feminino , Humanos , Imunoglobulina G/biossíntese , Imunoglobulina M/biossíntese , Masculino , Pessoa de Meia-Idade , Linfócitos T/imunologia , Linfócitos T/efeitos da radiação
15.
Pharmacol Ther ; 65(1): 47-73, 1995 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-7716182

RESUMO

Chronic viral hepatitis caused by hepatitis B, C or D may lead to cirrhosis, hepatocellular failure and hepatocellular carcinoma. The morbidity of these diseases has necessitated a prolonged search for effective therapy. Interferon-alpha has been studied widely, and remains the mainstay of treatment. Therapy for hepatitis B has now become possible with the demonstration that alpha-interferons inhibit hepatitis B virus (HBV) replication and that prolonged therapy can lead to a remission in disease. A number of other cytokines, including thymosin, are being evaluated. Currently used nucleoside analogues and anti-retroviral therapies used in human immunodeficiency virus infection have not proven useful in chronic hepatitis B. There are a number of new experimental nucleoside analogues with activity against HBV. Unfortunately, fialuridine has been associated with severe mitochondrial damage and hepatotoxicity. Other stereoisomers may be more active and less toxic, but the potential danger of these drugs indicates that large scale clinical trials should proceed cautiously. Experimental test systems for the preliminary investigation of antiviral compounds in hepatitis B and C will be required. Antisense oligodeoxyribonucleotides may inhibit the expression of the HBV genes. The natural history of hepatitis C is uncertain. Therapeutic trials of interferon-alpha indicated that a proportion of patients may respond to treatment with this agent. There is most information about 3 mU t.i.w. administered for 6 months. It is not yet clear whether this dose is optimal. Multivariate analysis of several pretreatment parameters indicate that patients without cirrhosis are more responsive to interferon. The influence of genotypes of hepatitis C is the subject of considerable interest at present. Patients with diverse circulating quasispecies may be less responsive to therapy than those with a single major species. Improved responses have been observed in patients with lower levels of circulating hepatitis C virus RNA.


Assuntos
Antivirais/uso terapêutico , Hepatite Viral Humana/tratamento farmacológico , Hepatite Viral Humana/prevenção & controle , Animais , Doença Crônica , Humanos
16.
Rev Med Virol ; 8(3): 153-159, 1998 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10398503

RESUMO

Several new nucleoside analogues have been developed which can inhibit hepatitis B replication by at least two logs. Lamivudine is the most widely studied of these new agents. Extensive phase II and III studies in patients with chronic hepatitis B have been completed. The sustained HBeAg seroconversion rate in patients who have received 100 mg lamivudine increases from 17% after a year of treatment to 27% after 2 years of treatment. Histological improvement has been noted in 38%-52% of lamivudine-treated patients, exceeding the improvement seen in placebo recipients. Similar histological improvement has been noted in anti-HBe-positive, DNA- positive patients. Lamivudine can prevent recurrence of hepatitis B after liver transplantation. It is likely that in the absence of immune clearance to accelerate elimination of infected hepatocytes, inhibitors of virus replication such as lamivudine will need to be administered for a long period to reduce the burden of infected hepatocytes in the liver, and to prevent relapse. The drug is generally well tolerated with few direct adverse events. Genotypic mutations have been observed in 23% (range 13-32%). In a study in Asian patients treated for two years the incidence of these mutants increased to 38% (as detected by PCR). Loss of susceptibility to lamivudine has been found to be due to reverse transcriptase amino acid substitutions. Lamivudine is likely to be reserved for patients with replicative hepatitis B infection with active chronic hepatitis, and/or active cirrhosis. Copyright 1998 John Wiley & Sons, Ltd.

17.
Transplantation ; 70(5): 809-15, 2000 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-11003363

RESUMO

BACKGROUND: This open, multicenter study was conducted to evaluate the efficacy and safety of lamivudine prophylaxis given to chronic hepatitis B virus-(HBV) infected patients before and after orthotopic liver transplantation (OLT). We now present long-term data that follow our previous short-term report. METHODS: Twenty-three patients were treated with lamivudine (100 mg orally, daily); 13 (57%), were serum HBV DNA positive (Abbott Genostics, Abbott Laboratories, Chicago, IL) at study entry. Patients received lamivudine for at least 4 weeks before OLT, and for up to 50 months (median 25 months) after OLT. RESULTS: Of the 23 treated patients, 17 survived to undergo OLT. Eleven patients (65%) survived up to 4 years (median 36 months) after OLT. One of the survivors stopped lamivudine because of a possible adverse reaction 9 months post-OLT, and prophylaxis with HBV immune globulin was then established. Ten survivors continue lamivudine. Eight long-term survivors have normal liver function without evidence of HBV reinfection. Of the 17 transplanted patients, 6 died. Four patients died (3 days to 5 months post-OLT) without evidence of graft reinfection. Two further patients died at 19 and 23 months post-OLT from graft failure. Both patients had YMDD variant detected at 12 months post-OLT. Two other patients with YMDD-variant HBV remain alive on lamivudine, 9 and 15 months after development of the variant. CONCLUSIONS: Lamivudine, given before and after OLT, prevents significant graft reinfection for the majority of treated patients. The study has also shown that lamivudine is extremely well tolerated by liver failure patients and for a prolonged period after transplantation.


Assuntos
Anticorpos Anti-Hepatite B/uso terapêutico , Hepatite B/prevenção & controle , Lamivudina/uso terapêutico , Biópsia , DNA Viral/sangue , Seguimentos , Hepatite B/patologia , Vírus da Hepatite B/genética , Humanos , Lamivudina/efeitos adversos , Transplante de Fígado/mortalidade , Taxa de Sobrevida
18.
Transplantation ; 72(3): 412-8, 2001 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-11502968

RESUMO

BACKGROUND: The effect of the type of immunosuppression on the course of posttransplant hepatitis C virus (HCV) infection is unclear. The aim of this study was to evaluate the histological outcome of posttransplant HCV infection with respect to initial immunosuppressive therapy in a cohort of 59 of 65 HCV positive transplant patients who survived at least 12 months. METHODS: Initial immunosuppressive therapy was triple (cyclosporine or tacrolimus and azathioprine and prednisolone) in 41, double (cyclosporine and prednisolone) in 5, and single (cyclosporine or tacrolimus) in 13 patients. There was blinded histological evaluation, based on necroinflammatory activity (grading score:0-18) and fibrosis (staging score: 0-6). The median histological follow-up was 36 (12-72) months. RESULTS: In the last liver biopsy, high necroinflammatory activity indicating chronic hepatitis (grading score > or =4) was found in 42 (71%) and severe fibrosis or cirrhosis (staging score > or =4) in 18 (30.5%) patients. High necroinflammatory activity was associated significantly with absence of pretransplant alcohol abuse (P=0.01) and relatively with occurrence of posttransplant acute lobular hepatitis C (P=0.055). Development of severe fibrosis or cirrhosis was significantly associated only with the type of initial immunosuppressive therapy. In particular, severe fibrosis or cirrhosis developed significantly more frequently in patients treated with triple or double (17/46 or 37%) than with single initial immunosuppressive therapy (1/13 or 7.7%) (adjusted for biopsy time: P=0.045). CONCLUSIONS: Severe fibrosis or cirrhosis appears to develop in 30% of HCV transplant patients in a median of 3 years and to be associated with heavier initial immunosuppression.


Assuntos
Hepatite C/complicações , Hepatite C/patologia , Imunossupressores/uso terapêutico , Cirrose Hepática/cirurgia , Cirrose Hepática/virologia , Transplante de Fígado , Fígado/patologia , Adulto , Biópsia , Feminino , Fibrose , Humanos , Masculino , Pessoa de Meia-Idade , Necrose , Valor Preditivo dos Testes , Recidiva , Índice de Gravidade de Doença
19.
Virus Res ; 64(2): 151-60, 1999 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10518711

RESUMO

Phylogenetic analysis of the 5' non-coding region (5'NCR) sequences has demonstrated that GB virus C/hepatitis G virus (GBV-C/HGV) can be separated into three major groups that correlate with the geographic origin of the isolate. Sequence analysis of the 5'NCR of 54 GBV-C/HGV isolates from 31 blood donors, 11 haemodialysis patients and 12 patients with chronic liver disease suggests the presence of a new variant of GBV-C/HGV in the province of KwaZulu Natal, South Africa. Eleven isolates grouped as group 1 variants (bootstrap support, 90%) found predominantly in West and Central Africa, a further six isolates grouped as group 2 variants (bootstrap support, 58%) found in Europe and North America; five of which grouped as 2a (bootstrap support, 91%) and one as 2b (bootstrap support, 87%), the latter also includes isolates from Japan, East Africa and Pakistan. Although the remaining 37 GBV-C/HGV isolates were more closely related to group 1 variants (bootstrap support, 90%), they formed a cluster, which was distinct from all other known GBV-C/HGV sequences. None of the South African isolates grouped with group 3 variants described from Southeast Asia. Three variants of GBV-C/HGV exist in KwaZulu Natal: groups 1, 2 and a new variant, which is distinct from other African isolates.


Assuntos
Flaviviridae/isolamento & purificação , Hepatite Viral Humana/virologia , RNA Viral/análise , Homologia de Sequência do Ácido Nucleico , Sequência de Bases , Doadores de Sangue , Doença Crônica , Flaviviridae/genética , Hepatite Viral Humana/genética , Humanos , Hepatopatias/terapia , Hepatopatias/virologia , Dados de Sequência Molecular , Filogenia , Diálise Renal , África do Sul
20.
Thromb Haemost ; 74(5): 1259-64, 1995 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8607106

RESUMO

We have undertaken a comprehensive study of hepatitis C virus (HCV) genotype and its clinical significance in haemophilic patients. 189 HCV RNA positive were typed, using the Simmonds classification scheme, by restriction fragment length polymorphism (RFLP) in an amplified segment of the 5' non-coding region of the HCV genome. Type 1 was found in 121 (64.0%), type 2 in 23 (12.2%), type 3 in 36 (19.0%), type 4 in 3 (1.6%), type 5 in 2 (1.1%) and mixed infection in 3 (1.6%). There were no type 6 infections and one patient (0.5%) could not be typed. Genotype was not associated with diagnosis, age, or with HIV infection. Type 1 was associated with higher serum HCV RNA levels, and with a poor response to interferon. Progression to hepatic decompensation has been seen less frequently in those with type 3 compared to type 1 infection (p = 0.07). Three out of eleven patients studied over a longer time course showed a change in genotype, the remainder were persistently infected with HCV type 1. In conclusion, HCV genotype has clinical relevance in the management of haemophilic patients. Those with type 1 are probably more likely to develop serious liver disease and since they respond poorly to interferon-alpha, should be considered for new treatment strategies aimed at sustained clearance of HCV RNA.


Assuntos
Genoma Viral , Hemofilia A/complicações , Hepacivirus/genética , Hepatite C/virologia , Doença Crônica , Hepacivirus/isolamento & purificação , Hepatite C/etiologia , Humanos , Polimorfismo de Fragmento de Restrição
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