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Harnessing the immune response to optimise treatment strategies in chronic hepatitis BGill, Upkar S. January 2018 (has links)
Chronic Hepatitis B (CHB) related cirrhosis and hepatocellular carcinoma (HCC) account for more than 750,000 deaths per year. Current therapies for CHB are limited in achieving HBsAg decline/loss and thus there remains a pressing need for curative treatment strategies. Although, Pegylated Interferon-α (Peg-IFNα) may be used, the majority of patients progress to nucleos(t)ide analogue (NUC) therapy due to treatment failure. Peg-IFNα and NUCs used in isolation act differentially on the immune response; Peg-IFNα induces NK cell activation and NUC therapy may partially restore T cell function. NK cells are important antiviral effectors, highly enriched in the liver, with the potential to regulate immunopathogenesis in persistent viral infections. Here we examined the NK cell pool in HBeAg-positive CHB patients treated with Peg-IFNα and whether changes in the NK cell repertoire are induced when patients are 'primed' with Peg-IFNα and importantly, whether these changes are sustained or further modulated long-term after switching to sequential NUC therapy. The cumulative expansion of CD56bright NK cells driven by 48-weeks of Peg-IFNα was maintained at higher than baseline levels throughout the subsequent 9 months of sequential NUCs. Peg- IFNα-expanded NK cells showed further augmentation in their expression of the activating NK cell receptors during sequential NUCs. The expansion in proliferating, functional NK cells and HBsAg reduction was greater and more pronounced following sequential NUCs than in patients treated with de novo NUCs. This highlights the potential benefit of Peg-IFNα- priming, providing mechanistic insights for the further optimisation of treatment strategies to achieve sustained responses. Sustained boosting of NK cells on sequential NUCs following Peg-IFNα-priming has not previously been described raising the potential of 'long-lived' NK cell populations in keeping with their emerging adaptive features. These findings provide a mechanistic and immunological rationale to explore combination/sequential treatment strategies for CHB, including on-treatment immune responses in the liver, whilst awaiting the emergence of new therapies in the field.
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An assessment of patients followed for Hepatitis B at the Department of Infectious Diseases at Örebro University Hospital : - Factors associated with significant liver fibrosis evaluated by transient elastographyAxelsson, Therese January 2019 (has links)
Introduction: Chronic hepatitis B (CHB) is a viral infection that can lead to development of fibrosis and hepatocellular carcinoma (HCC). Several factors affecting disease progression have been reported, such as sex and region of origin. Liver stiffness and fibrosis can be evaluated using transient elastography. The degree of fibrosis is an important parameter when deciding if treatment and HCC surveillance is indicated. Aim1) To compare patients with CHB according to sex and region of origin regarding the parameters liver stiffness, presence of significant fibrosis, hepatitis B e antigen (HBeAg) positivity, frequency of elevated alanine aminotransferase (ALT) levels and HCC surveillance.2) To identify factors associated with significant liver fibrosis. Methods: 410 patients with a registered doctor’s visit 2015–2018 at the Department of Infectious Diseases at Örebro University Hospital were included. A systematic review of medical records was performed and groups (women-men, regions of origin) were compared. Multivariate logistic regression was used to identify factors associated with significant fibrosis. Results: Men had significantly higher liver stiffness values, higher presence of significant fibrosis, and were more frequently under HCC surveillance compared to women. No other significant differences were found regarding the studied parameters, neither related to sex, nor to region of origin. Factors associated with significant fibrosis were: male sex, elevated ALT levels and hepatitis D virus (HDV) co-infection. Conclusions: Men had a higher frequency of significant fibrosis compared to women. Factors associated with significant fibrosis were male sex, elevated ALT values and HDV co-infection.
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IMMUNOREGULATION OF HEPATITIS B VIRUS INFECTION : RATIONALE AND CLINICAL APPLICATIONISHIKAWA, TETSUYA 08 1900 (has links)
No description available.
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Genotipagem do vírus da hepatite b em pacientes do Hospital Universitário da Universidade Federal de SergipeSena, Ludmila Oliveira Carvalho 27 September 2010 (has links)
INTRODUCTION: The virus of hepatitis B was classified in eight genotypes that vary with geographic distribution, presenting different clinical manifestations and responses to anti-viral treatment. PURPOSES: This work intends to determine the prevalence of genotypes in Sergipe Brasil and evaluate them according to clinical and histopathological findings. METHODOLOGY: In a transversal search, were evaluated 97 patients, all of them AgHBs chronic porters, with traces of viral replication. From those patients, we got DNA s amplification in 43 samples, that formed the core to genotypical determination. Those were also evaluated on AgHBe positivity, viral load (CV) quantification, aminotransferases (ALT) and histological data. RESULTS: The genotypes A and F, were identified, with 35/43 (81.4%) of genotype A. Twenty Five from 43 patients (58.1%) presented abnormal ALT level, AgHBe negative (23/43 53.5%) and CV below 10.000 copies/ml (20/32 62.5%). In the patients presenting genotype A, 20/32 (62.5%) presented CV below 10,000 copies/ml, but in those with the genotype F, 5/7 (71.4%) presented CV above 10,000 copies/ml (p=0,101). There was no statistic difference between viral genotype and histological findings. CONCLUSION: In Sergipe, the genotypes A and F were found, but predominates the genotype A. Important differences were not found among the genotypes relatively to clinical and laboratorial findings. / INTRODUÇÃO: O vírus da hepatite B foi classificado em oito genótipos que variam de acordo com a distribuição geográfica, apresentando diferentes manifestações clínicas e resposta ao tratamento anti-viral. OBJETIVOS: O estudo visa determinar a prevalência dos genótipos em Sergipe-Brasil, e avaliá-los de acordo com achados clínicos e histopatológicos.
METODOLOGIA: Em estudo transversal, foram avaliados 97 pacientes portadores crônicos do AgHBs com sinais de replicação viral. Destes, conseguiu-se amplificação do DNA em 43 amostras, as quais constituíram a casuística para realização de genotipagem. Foram, também, avaliados quanto à positividade do AgHBe, quantificação da carga viral (CV), aminotranferases (ALT) e avaliação histológica. RESULTADOS: Foram identificados os genótipos A e F, sendo 35/43 (81,4%) do genótipo A. Vinte e cinco/43 pacientes (58,1%) apresentaram ALT normais, AgHBe negativo (23/43, 53,5%) e CV inferior a 10.000 cópiasl/ml (20/32 (62,5%). Nos pacientes com genótipo A, 20/32 (62,5%) apresentaram CV inferior a 10.000 cópias/ml enquanto o genótipo F, 5/7 (71,4%) apresentaram CV superior a 10.000 cópias/ml (p=0,101). Não houve diferença estatística entre genótipo viral e características histológicas. CONCLUSÃO: Em Sergipe, foram descritos os genótipos A e F com predomínio do genótipo A. Não foram encontradas diferenças significantes entre os genótipos em relação às manifestações clínico-laboratoriais.
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Risks and Benefits of Discontinuation of Nucleos(t)ide Analogue Treatment: A Treatment Concept for Patients With HBeAg-Negative Chronic Hepatitis Bvan Bömmel, Florian, Berg, Thomas 09 February 2022 (has links)
Systematic discontinuation of long-term treatment with nucleos(t)ide analogues (NAs) is one strategy to increase functional cure rates in patients with chronic hepatitis B e antigen (HBeAg)-negative hepatitis B. Currently, available study results are heterogeneous; however, long-term hepatitis B surface antigen (HBsAg) loss rates of up to 20% have been reported in prospective trials. This review proposes criteria that can be used when considering NA discontinuation in patients with chronic hepatitis B virus (HBV). Discontinuing NA treatment frequently results in a virologic and biochemical relapse that runs through different phases: the lag phase, reactivation phase, and consolidation phase. The HBV-DNA flares observed during the reactivation phase are often transient and most likely represent a trigger for inducing a long-term immune control by specific CD8+ T cells, and therefore do not need immediate interventions but close follow-up evaluation. Low HBsAg levels at the time of treatment cessation predict a positive long-term response to NA discontinuation associated with a higher likelihood of HBsAg clearance. Other host and viral biomarkers are currently under evaluation that may prove to be helpful to further characterize the population that may benefit most from the finite NA treatment concept. Potential harmful biochemical flares during the reactivation phase need to be identified early and can be effectively terminated by reintroducing NA treatment. Hepatic decompensation represents a risk to patients with cirrhosis undergoing NA discontinuation. Therefore, the finite NA approach should only be considered after excluding advanced fibrosis and cirrhosis and if a close follow-up of the patient and supervision by an experienced physician can be guaranteed. Conclusion: For selected patients, NA discontinuation has become a powerful tool to achieve control over HBeAg-negative HBV infections. Its significant effect represents a challenge to novel treatment approaches, but it may also serve as their enhancer.
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Role of the inhibitory receptor LAIR-1 on NK cells in chronic hepatitis BHansi, Navjyot Kaur January 2018 (has links)
There are multiple immune mechanisms identified for persistence of hepatitis B virus (HBV) infection. This thesis considers the vital role that inhibitory receptors play in contributing to impairment of the adaptive immune system in chronic hepatitis B (CHB), and the potential role they play in the innate immune system, focusing on the inhibitory receptor leucocyte-associated immunoglobulin-like receptor (LAIR)-1. The unique aspect of this work is that for the first time LAIR-1 expression has been investigated on natural killer (NK) cells in CHB. Our striking findings of increased LAIR-1 expression on peripheral NK cells in CHB and an inverse correlation between expression and effector function suggest this inhibitory receptor could have a potential role in exhaustion of NK cells in CHB. We therefore additionally explored the expression of LAIR-1 on circulating NK cells from patients with hepatocellular carcinoma (HCC) and non-alcoholic fatty liver disease (NAFLD). The particular relevance of LAIR-1 to liver disease is that one of its major ligands is collagen. We demonstrated a downregulation of LAIR-1 expression on intrahepatic NK cells, which we postulate might occur following repetitive engagement with abundant collagen within the liver. In line with this, intrahepatic NK cells with a liver-resident (CXCR6+) phenotype had even lower LAIR-1 expression than liver infiltrating (non-resident, CXCR6-) NK cells. Furthermore, preliminary experiments display attenuation of the cytotoxic degranulation capacity (CD107a) by circulating NK cells from CHB patients upon exposure to plate-bound collagen. We demonstrate differential expression of LAIR-1 on NK cells in viral hepatitis, HCC and NAFLD and between peripheral and intrahepatic NK cells. Preliminary experiments demonstrate a role in inhibiting NK cell function suggesting this as a novel therapeutic target to harness the capacity of NK cells to control chronic infection and cancer.
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Caracterização clínica e molecular da hepatite crônica B AgHBe negativo na Amazônia Ocidental Brasileira.Victoria, Flamir da Silva 30 May 2007 (has links)
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Previous issue date: 2007-05-30 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / The infection for the HBV is one of the infections most frequent of the world, esteem in 350 million the number of chronic infections patients, being of Amazon Ocidental Brazilian person considered one of the regions of bigger prevalence of the HBV. The chronic hepatitis for the HBV are presented under two forms: Positive and negative AgHBe. The negative AgHBe forms are represented by two groups of patients: the inactive carriers of the AgHBs and the patients with chronic hepatitis B, 55 reacting AgHBs patients had been selected in the FMTAM have six months, natural of the Amazon Ocidental Brazilian person, after soroconversion of the AgHBe, with the purpose to determine HBV DNA for the PCR, to identify the genotypes of the VHB of reacting samples HBV DNA and to characterize the patients with chronic hepatitis B negative AgHBe, through the clinical and molecular analysis. The study he was of the descriptive type of case, with the separate patients in two groups: with hepatitis and without hepatitis in the histological examination. The prevalence of the hepatitis in the study was 63.64%, predominating the males sort, with a ratio of 1,9:1 in relation to the female, with average age of 42,5 years, being more frequently natural of the Southwestern Sub-region (32,73%). In the study it was observed that the time was a proportional variable to the evolution of the illness and in these patients the symptoms most frequent had been: dyspeptic symptom, asthenia and loss of the libido, with the majority of the patients presenting former and familiar history of previous contact with the HBV, being the esplenomegalia the signal most frequent (40%). The platelet counting enters the examinations, sérica albumin and activity of the protrombin had been significant for the diagnosis of the hepatitis. The alpha-fetoproteín more was raised in the patients with hepatitis and the hepatocelular carcinoma was detected in 3,63%. Three types of genotypes of the VHB had been
diagnosed, A, D and F in amplified samples of gene S. The genotype A, sub-genotype Afro-asiátic (AA) was most prevalent in the patients with hepatitis (54,54%). Mutations in these patients in 36,36% had been observed, with predominance of the mutations Core promoter (31,81%), to biggest prevalence in this study of the A genotype (AA). In the present study in the patients with hepatitis we find signals of fibrogenesis activity to ultrasound hepatic, demonstrating raised sensitivity of the examination in evaluating fibrosis hepatic (90,2%). In relation to the ultrasound signals of patology associations to the hepatitis, one observed lithiasis (18,18%) and focal injuries (5,45%). In the patients with hepatitis bigger and lesser signals of portal hipertension had been observed to ultrasound, respectively 38.18% and 40%. The application of the index of NIEC in these patients disclosed high risk of varices hemorrhage during the period of one year (37,8%). This study it showed to one high prevalence of the A genotype (AA) in patients with chronic hepatitis B negative AgHBe in the Amazon Ocidental Brazilian, opposing other studies on the predominance of the genotype F, probable consequence of the migratory influences of other Brazilian regions, has some decades, what she could be contributing for the change of the genotipic profile of the HBV in the region / A infecção pelo VHB é uma das infecções mais freqüentes do mundo, estima-se em 350 milhões o número de pacientes cronicamente infectados, sendo a Amazônia Ocidental Brasileira considerada uma das regiões de maior endemicidade do VHB. As hepatopatias crônicas pelo VHB apresentam-se sob duas formas: AgHBe positivo e AgHBe negativo. As formas AgHBe negativas são representadas por dois grupos de pacientes: os portadores inativos do AgHBs e os pacientes com hepatite crônica B (HCB). Foram selecionados na FMTAM 55 pacientes AgHBs reagentes há mais de seis meses, naturais da Amazônia Ocidental Brasileira, após soroconversão do AgHBe, com a finalidade de determinar o VHB DNA pela PCR, identificar os genótipos do VHB das amostras VHB DNA reagentes e caracterizar os pacientes com HCB AgHBe negativo, através da análise clínica e molecular. O estudo foi do tipo descritivo de caso, com os pacientes separados em dois grupos: com hepatite e sem hepatite no exame histopatológico. A prevalência da hepatite no estudo foi 63,64%, predominando o gênero masculino, com uma proporção de 1,9:1 em relação às mulheres, com idade média de 42,5 anos, sendo mais freqüentemente naturais da Sub-região Sudoeste (32,73%). No estudo foi observado que o tempo foi uma variável proporcional à evolução da doença e nestes pacientes os sintomas mais freqüentes foram: dispepsia, astenia e perda da libido, com a maioria dos pacientes apresentando história pregressa e familiar de contato prévio com o VHB, sendo a esplenomegalia o sinal mais freqüente (40%). Entre os exames a contagem plaquetária, albumina sérica e atividade da protrombina foram significativas para o diagnóstico da hepatite. A alfa-fetoproteína foi mais elevada nos pacientes com hepatite e o carcinoma hepatocelular foi detectado em 3,63%. Foram diagnosticados três tipos de genótipos do VHB: A, D e F, em amostras amplificadas do gene S. O genótipo A sub-genótipo Afro-asiático (AA) foi o mais prevalente nos pacientes com hepatite (54,54%). Observaram-se mutações nestes pacientes em 36,36%, com predomínio das mutações core promoter (31,81%), decorrentes da maior prevalência neste estudo do genótipo A (AA). No presente estudo nos pacientes com hepatite encontramos sinais de atividade fibrogênica ao ultrassom hepático, demonstrando elevada sensibilidade do exame em avaliar a fibrose hepática (90,2%). Em relação aos sinais ultrassonográficos de patologias associadas à hepatite, observou-se colecistopatias (18,18%) e lesões focais (5,45%). Nos pacientes com hepatite foram observados ao ultrassom sinais maiores
menores de hipertensão portal, respectivamente 38,18% e 40%. A aplicação do índice de NIEC nestes pacientes revelou elevado risco de hemorragia varicosa durante o período de um ano (37,8%). Este estudo mostrou uma elevada prevalência do genótipo A (AA) em pacientes com HCB AgHBe negativo na Amazônia Ocidental Brasileira, contrariando outros estudos sobre a predominância do genótipo F, reflexo provável das influências migratórias de outras regiões brasileiras, há várias décadas, o que poderia estar contribuindo para a mudança do perfil genotípico do VHB na região
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Prevalência de resistência primária aos antivirais utilizados no tratamento da hepatite B entre pacientes com infecção crônica pelo vírus da hepatite B não submetidos a tratamento / Prevalence of primary resistance to antivirals used in the treatment of hepatitis B among treatment-naïve patients with chronic hepatitis BGouvêa, Michele Soares Gomes 27 June 2014 (has links)
O objetivo principal deste estudo foi avaliar a frequência de cepas do HBV com mutações de resistência aos análogos nucleos(t)ídeos (AN) utilizados no tratamento da hepatite B entre indivíduos cronicamente infectados, não submetidos a tratamento, procedentes de diferentes regiões do Brasil. Além disso, foram avaliadas a presença de mutações que alteram a antigenicidade do HBsAg promovendo escape dos anticorpos anti-HBs; mutações nos genes pré-core/core e a associação dos diferentes subgenótipos com as mutações encontradas e características demográficas e laboratoriais dos pacientes. Foram incluídas 779 amostras de soro de pacientes com infecção crônica pelo HBV e virgens de tratamento com AN ou interferon, as quais foram coletadas no período de 2006 a 2011. Os pacientes eram procedentes dos seguintes estados brasileiros: Pará, Maranhão, Bahia, Minas Gerais, São Paulo, Paraná e Rio Grande do Sul. O DNA do HBV foi extraído das amostras de soro utilizando o Kit QIAamp DNA Blood Mini Kit (Qiagen) e posteriormente foi realizada a amplificação das regiões S/polimerase (S/P) e pré-core/core (PCC) do genoma viral por nested PCR. O fragmento amplificado foi submetido a sequenciamento direto em sequenciador automático de DNA (ABI 3500) e as sequências obtidas foram analisadas para identificação dos genótipos e subgenótipos do HBV, pesquisa de mutações na polimerase, no HBsAg e nos genes pré-core/core. A região S/Pol foi amplificada e sequenciada com sucesso em 702 amostras, as quais foram incluídas para atender aos objetivos deste estudo. Entre as 702 amostras analisadas sete genótipos e 12 subgenótipos do HBV foram identificados. O subgenótipo A1 foi o mais frequente (63,7%, 447/702), seguido pelo HBV/D3 (14,5%, 102/702). Os demais genótipos e subgenótipos encontrados e suas frequências foram as seguintes: A2 (3,3%, 23/702), A3 (0,1%, 1/702), B1 (0,1%, 1/702), B2 (0,1%, 1/702), C2 (0,9%, 6/702), D1 (0,9%, 6/702), D2 (4,6%, 32/702), D4 (5,1%, 36/702), D com subgenótipo não identificado (0,7%, 5/702), E (0,6%, 4/702), F2a (4,6%, 32/702), F4 (0,4%, 3/702), e G (0,4%, 3/702). Cepas do HBV com mutações de resistência (rtS202G, rtM204V/I, rtA194T, rtM250I, rtA181T/S, rtT184S) associadas ou não a mutações compensatórias (rtL80I, rtV173L, rtL180M, rtV207I) foram identificadas em 1,6% (11/702) das amostras analisadas. Cepas com mutações potencialmente associadas com resistência ao adefovir (rtS85A, rtL217R, rtI233V, rtN238T, rtN238D, rtN248H, rtV214A,e rtQ215S) ou ao entecavir (rtS219A) foram identificadas em 7,7% (54/702) e 2,6% (16/702) dos pacientes, respectivamente. Cinquenta e sete (8,5%) amostras apresentaram cepas do HBV com mutações na principal região hidrofílica do HBsAg previamente relacionadas com escape dos anticorpos anti-HBs ou com prejuízo na secreção do HBsAg. Foram feitas análises estatísticas para avaliar a correlação entre os subgenótipos do HBV mais frequentes na casuística (A1, A2, D1, D2, D3, D4 e F2a) e a presença de mutações nos genes PCC. Dentre as mutações nos genes PCC associadas com redução ou falha na expressão do HBeAg, as mutações A1762T/T1764A estiveram associadas aos subgenótipos A1 e F2a; G1862T e mutações nas posições 1809-1812 ao subgenótipo A1; G1896A e/ou G1899A aos subgenótipos D2, D3 e D4. Mutações associadas com evolução da doença foram detectadas e entre essas as mutações C1766T e T1768A estiveram associadas aos subgenótipos A1 e F2a, e a mutação G1888A foi associada ao subgenótipo A1. As cepas do HBV que circulam nas diferentes regiões brasileiras estudadas apresentam grande variabilidade genética e a distribuição dos genótipos e subgenótipos reflete a formação histórica de cada região e do fluxo migratório mais recente. A frequência de cepas do HBV com mutações de resistência aos AN circulando entre pacientes virgens de tratamento com esses medicamentos nas diferentes regiões do Brasil estudadas é baixa, sendo que o perfil de mutações que confere resistência total à lamivudina e parcial ao entecavir parece ser o mais disseminado. Embora tenham sido detectados casos de infecção com cepas do HBV portando mutações com grande impacto na antigenicidade dessa proteína todas as amostras apresentaram HBsAg detectável. Pacientes com HBeAg negativo foram mais frequentes na casuística estudada, independente do subgenótipo. As mutações encontradas nos genes PCC sugerem que há perfis de mutações diferentes envolvidos na negatividade do HBeAg para cada subgenótipo / The main aim of this study was to evaluate the frequency of HBV strains harboring mutations that confer resistance to nucleos(t)ide analogues (NA) used to hepatitis B treatment among treatment-naïve patients with chronic hepatitis B from different Brazilian region. Furthermore, we evaluated the presence of mutations that alter the antigenicity of HBsAg causing anti-HBs escape; mutations in genes pre-core/core and the association of different subgenotypes with the mutations detected and demographic and laboratory characteristics of the patients. Serum samples from 779 treatment-naïve patients with chronic HBV infection were included in this study. The samples were collected between 2006 to 2011 and the patients were from the following states: Pará, Maranhão, Bahia, Minas Gerais, São Paulo, Paraná and Rio Grande do Sul. HBV DNA was extracted from serum samples using the QIAamp DNA Blood Mini Kit (Qiagen) and amplification of S/polymerase (S/Pol) and pre-core/core (PCC) regions were performed by nested PCR. The amplified PCR products were submitted to sequencing in an automatic DNA sequencer (ABI 3500). The sequences obtained were analyzed to classify HBV genotypes/subgenotypes and to analyze the presence of mutations. S/Pol region was amplified and sequenced successfully from 702 samples, which were included in this study. Among these 702 samples, seven genotypes and 12 subgenotypes have been identified. HBV subgenotype A1 was the most frequent (63.7%, 447/702), followed by HBV/D3 (14.5%; 102/ 702). The remaining genotypes and subgenotypes identified and their frequencies were as follows: A2 (3.3%, 23/702), A3 (0.1%, 1/702), B1 (0.1%, 1/702), B2 (0.1%, 1/702), C2 (0.9%, 6/702), D1 (0.9%, 6/702), D2 (4.6%, 32/702), D4 (5.1%, 36/702), D unclassified subgenotype (0.7%, 5/702), E (0.6%, 4/702), F2a (4.6%, 32/702), F4 (0.4%, 3/702), and G (0.4%, 3/702). HBV strains harboring mutations conferring NA resistance alone (rtS202G, rtM204V/I, rtA194T, rtM250I, rtA181T/S, rtT184S) or combined with compensatory mutations (rtL80I, rtV173L, rtL180M, rtV207I) were identified in 1.6% (11/702) of the patients. Isolates harboring mutations potentially associated with adefovir resistance (rtS85A, rtL217R, rtI233V, rtN238T, rtN238D, rtN248H, rtV214A, and rtQ215S) or entecavir resistance (rtS219A) were identified in 7.7% (54/702) and 2.6% (16/702) of the patients, respectively. HBV with HBsAg mutations previous related with anti-HBs escape or impaired secretion were detected in 8.5% (57/702) of the samples. Statistical analyzes were performed to assess the correlation between the more frequent HBV subgenotypes found in this study (A1, A2, D1, D2, D3, D4 and F2a ) and mutations in PCC genes. Among the mutations found in these genes that were associated with reduction or failure in HBeAg synthesis, A1762T/T1764A mutations were associated to subgenotypes A1 and F2a; G1862T and mutations at positions 1809-1812 to subgenotype A1; G1896A and/or G1899A to subgenotypes D2, D3 and D4. Other mutations associated with disease progression were found: C1766T and T1768A mutations were associated with subgenotypes A1 and F2a, and the G1888A mutation was associated with subgenotype A1. HBV strains circulating in different Brazilian regions studied showed high genetic variability and distribution of genotypes and subgenotypes reflects the population formation history of each region and the occurrence of recent events of migration. The frequency of HBV strains with NA resistance mutations circulating among treatment-naive patients in different regions of Brazil studied is low and the profile of mutations that confer total resistance to lamivudine and partial resistance to entecavir is more widespread. Although some cases of infection have been detected with HBV strains carrying mutations associated with major impact on the antigenicity of this protein, all samples had detectable HBsAg. HBeAg negative cases were more frequent in the studied population, regardless of subgenotype. Different pattern of mutations were found in PCC genes, suggesting that different mechanisms are involved in HBeAg negativity for each subgenotype
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Quantificação do HBsAg : uma nova alternativa para o monitoramento da hepatite B crônica? / Quantification of hbsag: a new alternative for monitoring of chronic hepatitis b?Moura, Renata Dultra Torres 22 April 2014 (has links)
Although the level of HBsAg is determined only qualitatively in routine clinical practice, recent data suggest that its quantification can assist or replace the viral load of HBV DNA in monitoring of HBV replication, which would be an easier and more economical alternative. Thus, the aim of this study was to correlate the levels of HBsAg with viral load of HBV DNA and other laboratory (HBeAg, ALT and AST) and histological (activity and fibrosis) findings in patients with chronic hepatitis B. A prospective, observational, cross-sectional study was performed on 128 patients with chronic hepatitis B, aged over 18 years, from the Hepatology Service of the University Hospital of Sergipe. Categorical variables were presented as frequencies and percentages with range of 95% where applicable. For the correlation analysis we used the Spearman test. It was
considered that the correlations had statistical significance when ρ≤ 0.05. The overall correlation between HBV viral load and quantitative HBsAg was weak (ρ= 0.197, ρ= 0.026), and this same correlation was also weak and not statistically significant in HBeAg-positive patients (ρ= 0.233,
ρ= 0.263). However, a strong correlation between HBsAg and HBV DNA >20,000 in HBeAgpositive patients was found. A regular correlation between HBsAg and HBV DNA in patients who
were not on treatment (*ρ= 0394; ρ<0.001) was found and there was no significant correlation in patients receiving treatment (*ρ= -0.061; ρ= 0.673). No statistically significant association was observed between the levels of HBsAg and HBeAg, even when considering only the positive
HBeAg (ρ: 0.121; ρ=0.565) and even not only the negative HBeAg (ρ =-0.067; ρ=0.501). The correlation between HBV DNA and HBeAg positive was fair (ρ =0.444; ρ=0.026). There was no
statistical correlation between the levels of HBsAg and aminotransferases (ALT and AST). The distribution of HBsAg values did not differ between the degree of activity (ρ= 0.17) and fibrosis (ρ= 0.20). Conclusion: Our results show that, in general, the correlation between levels of HBsAg and HBV DNA exists, but it proved to be weak. Also, they suggest that HBsAg better reflects HBV DNA in the initial replicative phase of chronic hepatitis B, when patients present HBV reagent and high titers of HBeAg viral load. They also show that there is no association of HBsAg with aminotransferases or with the degree of activity and liver fibrosis. / Embora o nível de HBsAg seja determinado apenas qualitativamente na prática clínica rotineira, dados recentes sugerem que a sua quantificação pode auxiliar ou substituir a carga viral do VHB DNA no monitoramento da replicação do VHB, o que seria uma alternativa mais fácil e econômica. Desta forma, objetivou-se com este estudo, correlacionar os níveis de HBsAg com a carga viral do VHB DNA e com outros achados laboratoriais (HBeAg, ALT e AST) e histológicos (atividade e fibrose) em pacientes com hepatite B Crônica. Foi realizado um estudo observacional, prospectivo, transversal, com 128 pacientes portadores de hepatite B crônica, com idade igual ou
superior a 18 anos, oriundos do Serviço de Hepatologia do Hospital Universitário de Sergipe. As variáveis categóricas foram apresentadas através de frequências e percentuais com intervalo de 95% quando pertinente. Para a análise das correlações utilizou-se o teste de Spearman. Considerou-se que as correlações possuíam significância estatística quando p ≤ 0,05. A correlação global entre a carga viral do VHB e o HBsAg quantitativo foi fraca (ρ=0,197; p=0,026); esta mesma correlação também foi fraca e sem significância estatística nos pacientes HBeAg positivos (ρ =0.233; p=0,263). Porém, foi encontrada uma forte correlação entre o HBsAg e o VHB DNA >
20.000, nos pacientes HBeAg positivos. Foi observada uma correlação regular entre o HBsAg e o VHB DNA nos pacientes que não estavam em tratamento (*ρ= 0394; p <0,001) e não existiu correlação significante nos pacientes em tratamento (*ρ= -0,061; p= 0,673). Não se observou associação estatisticamente significante entre os níveis de HBsAg e HBeAg, nem quando se considerou apenas os HBeAg positivos (ρ: 0,121; p=0,565) e nem apenas os HBeAg negativos (ρ =-0,067; p=0,501). A correlação entre o VHB DNA e o HBeAg positivo foi regular (ρ =0,444; p=0,026). Não foi verificada correlação estatística entre os níveis de HBsAg e as aminotransferases (ALT e AST). A distribuição dos valores de HBsAg não diferiu entre os graus de atividade (p=0,17) e fibrose (p=0,20). Conclusão: Os nossos resultados mostram que, de uma
forma geral, a correlação entre os níveis de HBsAg e VHB DNA existe, mas é fraca. E sugerem que o HBsAg reflete melhor o VHB DNA na fase replicativa inicial da hepatite B crônica, quando
os pacientes possuem HBeAg reagente e altos títulos de carga viral do VHB. Demonstram também que não existe associação do HBsAg com aminotransferases nem com o grau de atividade
e fibrose hepática.
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Prevalência de resistência primária aos antivirais utilizados no tratamento da hepatite B entre pacientes com infecção crônica pelo vírus da hepatite B não submetidos a tratamento / Prevalence of primary resistance to antivirals used in the treatment of hepatitis B among treatment-naïve patients with chronic hepatitis BMichele Soares Gomes Gouvêa 27 June 2014 (has links)
O objetivo principal deste estudo foi avaliar a frequência de cepas do HBV com mutações de resistência aos análogos nucleos(t)ídeos (AN) utilizados no tratamento da hepatite B entre indivíduos cronicamente infectados, não submetidos a tratamento, procedentes de diferentes regiões do Brasil. Além disso, foram avaliadas a presença de mutações que alteram a antigenicidade do HBsAg promovendo escape dos anticorpos anti-HBs; mutações nos genes pré-core/core e a associação dos diferentes subgenótipos com as mutações encontradas e características demográficas e laboratoriais dos pacientes. Foram incluídas 779 amostras de soro de pacientes com infecção crônica pelo HBV e virgens de tratamento com AN ou interferon, as quais foram coletadas no período de 2006 a 2011. Os pacientes eram procedentes dos seguintes estados brasileiros: Pará, Maranhão, Bahia, Minas Gerais, São Paulo, Paraná e Rio Grande do Sul. O DNA do HBV foi extraído das amostras de soro utilizando o Kit QIAamp DNA Blood Mini Kit (Qiagen) e posteriormente foi realizada a amplificação das regiões S/polimerase (S/P) e pré-core/core (PCC) do genoma viral por nested PCR. O fragmento amplificado foi submetido a sequenciamento direto em sequenciador automático de DNA (ABI 3500) e as sequências obtidas foram analisadas para identificação dos genótipos e subgenótipos do HBV, pesquisa de mutações na polimerase, no HBsAg e nos genes pré-core/core. A região S/Pol foi amplificada e sequenciada com sucesso em 702 amostras, as quais foram incluídas para atender aos objetivos deste estudo. Entre as 702 amostras analisadas sete genótipos e 12 subgenótipos do HBV foram identificados. O subgenótipo A1 foi o mais frequente (63,7%, 447/702), seguido pelo HBV/D3 (14,5%, 102/702). Os demais genótipos e subgenótipos encontrados e suas frequências foram as seguintes: A2 (3,3%, 23/702), A3 (0,1%, 1/702), B1 (0,1%, 1/702), B2 (0,1%, 1/702), C2 (0,9%, 6/702), D1 (0,9%, 6/702), D2 (4,6%, 32/702), D4 (5,1%, 36/702), D com subgenótipo não identificado (0,7%, 5/702), E (0,6%, 4/702), F2a (4,6%, 32/702), F4 (0,4%, 3/702), e G (0,4%, 3/702). Cepas do HBV com mutações de resistência (rtS202G, rtM204V/I, rtA194T, rtM250I, rtA181T/S, rtT184S) associadas ou não a mutações compensatórias (rtL80I, rtV173L, rtL180M, rtV207I) foram identificadas em 1,6% (11/702) das amostras analisadas. Cepas com mutações potencialmente associadas com resistência ao adefovir (rtS85A, rtL217R, rtI233V, rtN238T, rtN238D, rtN248H, rtV214A,e rtQ215S) ou ao entecavir (rtS219A) foram identificadas em 7,7% (54/702) e 2,6% (16/702) dos pacientes, respectivamente. Cinquenta e sete (8,5%) amostras apresentaram cepas do HBV com mutações na principal região hidrofílica do HBsAg previamente relacionadas com escape dos anticorpos anti-HBs ou com prejuízo na secreção do HBsAg. Foram feitas análises estatísticas para avaliar a correlação entre os subgenótipos do HBV mais frequentes na casuística (A1, A2, D1, D2, D3, D4 e F2a) e a presença de mutações nos genes PCC. Dentre as mutações nos genes PCC associadas com redução ou falha na expressão do HBeAg, as mutações A1762T/T1764A estiveram associadas aos subgenótipos A1 e F2a; G1862T e mutações nas posições 1809-1812 ao subgenótipo A1; G1896A e/ou G1899A aos subgenótipos D2, D3 e D4. Mutações associadas com evolução da doença foram detectadas e entre essas as mutações C1766T e T1768A estiveram associadas aos subgenótipos A1 e F2a, e a mutação G1888A foi associada ao subgenótipo A1. As cepas do HBV que circulam nas diferentes regiões brasileiras estudadas apresentam grande variabilidade genética e a distribuição dos genótipos e subgenótipos reflete a formação histórica de cada região e do fluxo migratório mais recente. A frequência de cepas do HBV com mutações de resistência aos AN circulando entre pacientes virgens de tratamento com esses medicamentos nas diferentes regiões do Brasil estudadas é baixa, sendo que o perfil de mutações que confere resistência total à lamivudina e parcial ao entecavir parece ser o mais disseminado. Embora tenham sido detectados casos de infecção com cepas do HBV portando mutações com grande impacto na antigenicidade dessa proteína todas as amostras apresentaram HBsAg detectável. Pacientes com HBeAg negativo foram mais frequentes na casuística estudada, independente do subgenótipo. As mutações encontradas nos genes PCC sugerem que há perfis de mutações diferentes envolvidos na negatividade do HBeAg para cada subgenótipo / The main aim of this study was to evaluate the frequency of HBV strains harboring mutations that confer resistance to nucleos(t)ide analogues (NA) used to hepatitis B treatment among treatment-naïve patients with chronic hepatitis B from different Brazilian region. Furthermore, we evaluated the presence of mutations that alter the antigenicity of HBsAg causing anti-HBs escape; mutations in genes pre-core/core and the association of different subgenotypes with the mutations detected and demographic and laboratory characteristics of the patients. Serum samples from 779 treatment-naïve patients with chronic HBV infection were included in this study. The samples were collected between 2006 to 2011 and the patients were from the following states: Pará, Maranhão, Bahia, Minas Gerais, São Paulo, Paraná and Rio Grande do Sul. HBV DNA was extracted from serum samples using the QIAamp DNA Blood Mini Kit (Qiagen) and amplification of S/polymerase (S/Pol) and pre-core/core (PCC) regions were performed by nested PCR. The amplified PCR products were submitted to sequencing in an automatic DNA sequencer (ABI 3500). The sequences obtained were analyzed to classify HBV genotypes/subgenotypes and to analyze the presence of mutations. S/Pol region was amplified and sequenced successfully from 702 samples, which were included in this study. Among these 702 samples, seven genotypes and 12 subgenotypes have been identified. HBV subgenotype A1 was the most frequent (63.7%, 447/702), followed by HBV/D3 (14.5%; 102/ 702). The remaining genotypes and subgenotypes identified and their frequencies were as follows: A2 (3.3%, 23/702), A3 (0.1%, 1/702), B1 (0.1%, 1/702), B2 (0.1%, 1/702), C2 (0.9%, 6/702), D1 (0.9%, 6/702), D2 (4.6%, 32/702), D4 (5.1%, 36/702), D unclassified subgenotype (0.7%, 5/702), E (0.6%, 4/702), F2a (4.6%, 32/702), F4 (0.4%, 3/702), and G (0.4%, 3/702). HBV strains harboring mutations conferring NA resistance alone (rtS202G, rtM204V/I, rtA194T, rtM250I, rtA181T/S, rtT184S) or combined with compensatory mutations (rtL80I, rtV173L, rtL180M, rtV207I) were identified in 1.6% (11/702) of the patients. Isolates harboring mutations potentially associated with adefovir resistance (rtS85A, rtL217R, rtI233V, rtN238T, rtN238D, rtN248H, rtV214A, and rtQ215S) or entecavir resistance (rtS219A) were identified in 7.7% (54/702) and 2.6% (16/702) of the patients, respectively. HBV with HBsAg mutations previous related with anti-HBs escape or impaired secretion were detected in 8.5% (57/702) of the samples. Statistical analyzes were performed to assess the correlation between the more frequent HBV subgenotypes found in this study (A1, A2, D1, D2, D3, D4 and F2a ) and mutations in PCC genes. Among the mutations found in these genes that were associated with reduction or failure in HBeAg synthesis, A1762T/T1764A mutations were associated to subgenotypes A1 and F2a; G1862T and mutations at positions 1809-1812 to subgenotype A1; G1896A and/or G1899A to subgenotypes D2, D3 and D4. Other mutations associated with disease progression were found: C1766T and T1768A mutations were associated with subgenotypes A1 and F2a, and the G1888A mutation was associated with subgenotype A1. HBV strains circulating in different Brazilian regions studied showed high genetic variability and distribution of genotypes and subgenotypes reflects the population formation history of each region and the occurrence of recent events of migration. The frequency of HBV strains with NA resistance mutations circulating among treatment-naive patients in different regions of Brazil studied is low and the profile of mutations that confer total resistance to lamivudine and partial resistance to entecavir is more widespread. Although some cases of infection have been detected with HBV strains carrying mutations associated with major impact on the antigenicity of this protein, all samples had detectable HBsAg. HBeAg negative cases were more frequent in the studied population, regardless of subgenotype. Different pattern of mutations were found in PCC genes, suggesting that different mechanisms are involved in HBeAg negativity for each subgenotype
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