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1.
Ann Hepatol ; 29(1): 101156, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37758118

RESUMO

INTRODUCTION AND OBJECTIVES: Occult hepatitis B virus (HBV) infection (OBI) is characterised by low levels of hepatitis B virus (HBV) DNA in the blood/liver of patients with negative hepatitis B surface antigen (HBsAg). This study aimed to determine the OBI prevalence and virological characteristics (viral genotypes and HBsAg mutants) in patients with an "anti-HBc only" serological profile. MATERIALS AND METHODS: A total of 24 900 serum samples were routinely screened for hepatitis B markers over a five-year period. All anti-HBc-positive/HBsAg-negative/anti-HBs-negative sera were selected and analysed for the presence of HBV DNA. Mutational analyses of the HBs gene and polymerase gene sequences were performed. RESULTS: 1749 (7.02%) sera were anti-HBc positive, and 113 (0.45%) sera had an "anti-HBc only" serological profile (HBsAg/anti-HBs negative). HBV DNA was detected in 12/113 (10.61%) "anti-HBc only" positive sera, representing 0.048% of all routinely tested samples. Due to extremely low viremia, HBV genome was successfully sequenced in only two sera where subgenotype D3 was confirmed. Mutational analyses of the S gene revealed multiple missense mutations. In addition to the M133I, Y134F, and G145R mutations, already associated with diagnostic escape, we also found nine novel OBI-related S-gene mutations - S136Y, F158L, K160N, E164G, S167L, A168V, L175S, S210I and F212C. CONCLUSIONS: We detected multiple known and novel S gene mutations in 2/12 (16.6%) OBI cases, nevertheless, further studies are required to determine their role in the pathogenesis of OBI. Understanding the frequencies of clinically relevant HBV mutations may contribute to improvement of diagnostic protocols.


Assuntos
Hepatite B Crônica , Hepatite B , Adulto , Humanos , Vírus da Hepatite B/genética , Antígenos de Superfície da Hepatite B , DNA Viral/genética , Prevalência , Croácia/epidemiologia , Hepatite B/diagnóstico , Hepatite B/epidemiologia , Anticorpos Anti-Hepatite B
2.
São Paulo med. j ; São Paulo med. j;141(3): e2022147, 2023. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1432440

RESUMO

ABSTRACT BACKGROUND: Occult hepatitis B virus infection (OBI) is defined as the presence of hepatitis B virus (HBV) deoxyribonucleic acid (DNA) in the liver of individuals with undetectable hepatitis B virus surface antigen (HBsAg) in the serum. The actual prevalence of OBI and its clinical relevance are not yet fully understood. OBJECTIVE: To evaluate the prevalence of HBV DNA in liver biopsies of HBsAg-negative patients with chronic liver disease of different etiologies in a referral center in Brazil and compare two different HBV DNA amplification protocols to detect HBV. DESIGN AND SETTING: This cross-sectional observational study was conducted at the Liver Outpatient Clinic, Hospital das Clínicas, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil, between January 2016 and December 2019. METHODS: HBV DNA was investigated in 104 liver biopsy samples from individuals with chronic liver disease of different etiologies, in whom HBsAg was undetectable in serum by nested-polymerase chain reaction (nested-PCR), using two different protocols. RESULTS: OBI, diagnosed by detecting HBV DNA using both protocols, was detected in 6.7% of the 104 individuals investigated. Both protocols showed a good reliability. CONCLUSION: In addition to the differences in the prevalence of HBV infection in different regions, variations in the polymerase chain reaction technique used for HBV DNA amplification may be responsible for the large variations in the prevalence of OBI identified in different studies. There is a need for better standardization of the diagnostic methods used to diagnose this entity.

4.
Rev. bras. pesqui. méd. biol ; Braz. j. med. biol. res;55: e12320, 2022. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1403901

RESUMO

This study explored the correlation between interleukins (IL)-12, IL-18, and IL-21 and the viral load in patients with chronic hepatitis B virus (HBV). A total of 142 patients were consecutively enrolled. All were hepatitis B surface antigen (HBsAg)-positive for >6 months and did not receive drug therapy. An ELISA kit was used to test the IL-12, IL-18, IL-21, and acetylcholinesterase (AchE) levels in serum samples from chronic HBV patients and healthy control groups. The amounts of IL-12 and IL-18 were highest in the 5-6log10 (high viral load) group, while IL-21 was highest in the 3-4log10 (low viral load) group. Also, the IL-21 amount was decreased in the HBsAg+/HBeAg/HBcAb+ group, and IL-12, IL-18, and IL-21 were decreased in the normal alanine aminotransferase (ALT) group compared to the abnormal ALT group. These data suggested that IL-12, IL-18, and IL-21 serum levels were positively correlated with disease progression and could reflect disease severity for different HBV-DNA loads. Detection of IL-12, IL-18, and IL-21 levels was found to be helpful for evaluating the degree of liver cell damage and predicting the progression of hepatitis.

5.
Rev. cuba. med. trop ; 72(2): e522, mayo.-ago. 2020. tab, graf
Artigo em Espanhol | LILACS, CUMED | ID: biblio-1149912

RESUMO

Introducción: Los ensayos para cuantificar el ADN del virus de la hepatitis B (VHB) o carga viral son imprescindibles en el diagnóstico y en el seguimiento de los pacientes con hepatitis B crónica; de ahí que estén disponibles estuches diagnósticos para esta función. En el presente estudio se muestra la validación de SUMASIGNAL VHB (un paso), el cual es un sistema de reacción en cadena de la polimerasa en tiempo real (RCP-TR) para la cuantificación del genoma del VHB, propuesto por el Centro de Inmunoensayo. Objetivo: Evaluar el desempeño analítico de SUMASIGNAL VHB (un paso). Métodos: Se utilizó un panel de 80 muestras de suero bien caracterizadas y el Tercer Estándar Internacional de la OMS para las técnicas de amplificación de ácidos nucleicos del virus de la hepatitis B. Se determinaron las características del ensayo como especificidad clínica, especificidad analítica (reactividad cruzada), rango lineal o linealidad y exactitud, precisión intraensayo y comparación con un ensayo de referencia. Resultados: La especificidad analítica y clínica fue del 100 por ciento. Al evaluar la linealidad y exactitud con un estándar de referencia de la OMS, se obtuvo que la totalidad de las diferencias entre los Log10 del valor obtenido y el de referencia resultaron inferiores a 0,5 Log10 (r= 0,9977 y r2= 0,9954). Además, se obtuvieron bajos coeficientes de variación intraensayo. La evaluación comparativa con el estuche comercial Artus HBV RG PCR kit mostró una correlación fuerte (r= 0,8882). Conclusiones: SUMASIGNAL VHB (un paso) es un ensayo fácil de realizar manualmente, es rápido e incluye reactivos de extracción de ácidos nucleicos. Teniendo en cuenta la validez del método para el uso previsto, puede ser recomendado para su introducción en el diagnóstico, la vigilancia y la indicación de tratamiento en los pacientes con hepatitis B crónica(AU)


Introduction: Assays to quantify hepatitis B virus (HBV) DNA or viral load are indispensable for the diagnosis and follow-up of patients with chronic hepatitis B, hence the availability of diagnostic kits for this purpose. The present study deals with the validation of HBV SUMASIGNAL (one step), a real time polymerase chain reaction (RT-PCR) system for quantification of the HBV genome proposed by the Immunoassay Center. Objective: Evaluate the analytical performance of HBV SUMASIGNAL (one step). Methods: Use was made of a panel of 80 well characterized serum samples and the Third WHO International Standard for hepatitis B virus nucleic acid amplification techniques. Determination was performed of assay characteristics such as clinical specificity, analytical specificity (cross-reactivity), linear range or linearity and accuracy, intra-assay precision and comparison with a reference assay. Results: Analytical and clinical specificity was 100 percent. Evaluation of linearity and accuracy with a WHO reference standard revealed that all the differences between the log10 of the value obtained and the reference value were lower than 0.5 log10 (r= 0.9977 and r2= 0.9954). The intra-assay variation coefficients obtained were low. Comparative evaluation with the commercial Artus HBV RG PCR kit showed a strong correlation (r= 0.8882). Conclusions: The assay HBV SUMASIGNAL (one step) is easy to conduct manually, fast and includes reagents for nucleic acid extraction. Based on the validity of the method for the use in mind, it may be recommended for incorporation into the diagnosis, surveillance and treatment of patients with chronic hepatitis B(AU)


Assuntos
Humanos , Vírus da Hepatite B/isolamento & purificação , Técnicas de Amplificação de Ácido Nucleico/métodos , Reação em Cadeia da Polimerase em Tempo Real/métodos , Estudo de Validação
6.
J Virol Methods ; 256: 100-106, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29514044

RESUMO

For quantification of hepatitis B virus DNA (HBV DNA), commercial assays are used with serum or plasma samples, but oral fluid samples could be an alternative for HBV diagnosis due to ease of collection. This study aims to develop in-house real time PCR using synthetic curve for HBV DNA quantification for serum and oral fluid samples. Samples were collected from 103 individuals (55 HBsAg reactive and HBV DNA reactive by commercial assay and 48 without HBV markers) and submitted to two in-house real time PCR assays for HBV pre-S/S region with different standard curves: qPCR plasmidial and qPCR synthetic. A total of 27 serum samples were HBV DNA positive by qPCR plasmidial and 40 with qPCR synthetic (72% and 85% of concordance, respectively). Quantitative PCR synthetic presented efficiency of 99% and sensitivity of 2log10 copies/mL. Among oral fluid samples, five and ten were detected using qPCR plasmidial and synthetic, respectively. This study demonstrated that qPCR synthetic using serum samples could be used as alternative for HBV DNA quantification due to its sensitivity. In addition, it was possible to quantify HBV DNA in oral fluid samples suggesting the potential of this specimen for molecular diagnosis of HBV.


Assuntos
DNA Viral , Vírus da Hepatite B/genética , Hepatite B/virologia , Reação em Cadeia da Polimerase em Tempo Real , Reações Cruzadas , Hepatite B/imunologia , Antígenos de Superfície da Hepatite B/imunologia , Vírus da Hepatite B/imunologia , Humanos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Carga Viral
7.
Mem. Inst. Oswaldo Cruz ; 113(1): 62-65, Jan. 2018. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1040579

RESUMO

In occult hepatitis B infection (OBI), hepatitis B virus DNA (HBV DNA) can be detected in serum samples; however, oral fluid collection for detection of HBV DNA has not yet been explored, despite the availability of collection devices. Serum and oral fluid samples from 45 hepatitis B core antibody (anti-HBc)-positive patients were collected for the amplification of the HBV polymerase gene. HBV DNA was detected in five serum and four oral fluid samples (the detection limit for oral fluid was 1.656 log IU/mL in paired serum). In conclusion, simple methodologies of sample collection and in-house polymerase chain reaction (PCR) allowed detection of HBV DNA, and these could be used to improve the diagnosis of OBI, especially in locations with limited resources.


Assuntos
Humanos , Masculino , Feminino , Adulto , Idoso , Saliva/virologia , DNA Viral/análise , Hepatite B/diagnóstico , Anticorpos Anti-Hepatite B/análise , Antígenos de Superfície da Hepatite B/análise , DNA Viral/sangue , Vírus da Hepatite B/isolamento & purificação , Vírus da Hepatite B/genética , Reação em Cadeia da Polimerase , Carga Viral , Pessoa de Meia-Idade
8.
Rev. cuba. med. trop ; 68(3): 179-190, sep.-dic. 2016. ilus, tab
Artigo em Espanhol | LILACS, CUMED | ID: biblio-844990

RESUMO

Introducción: la infección oculta por el virus de la hepatitis B se caracteriza por la presencia en suero o plasma del genoma viral y anticuerpos contra la proteína de la cápsida (anti-HBc) en ausencia del marcador de infección.Objetivos: detectar la IOB en los pacientes hemodializados e identificar la posible relación de la IOB con la infección por el virus de la hepatitis C y variables sociodemográficas y epidemiológicas.Métodos: se estudiaron 709 muestras de pacientes provenientes de 18 unidades de hemodiálisis de Cuba. Se determinaron marcadores de infección, exposición e inmunidad al virus de la hepatitis B. Las muestras con HBsAg negativo, anti-HBc positivo y niveles de anti-HBs < 50 UI/L se les analizó la detección de ADN del virus de la hepatitis B y marcadores de lvirus de la hepatitis C.Resultados: las prevalencias de la infección y la exposición al virus de la hepatitis B fueron de 6,9 por ciento y 28,6 por ciento, respectivamente. El 4,3 por ciento de las muestras tuvieron criterio de infección oculta por el virus de la hepatitis B ; esta se detectó en el 58,1 por ciento (18/31) de los casos, con cargas virales menores de 105 UI/mL. La prevalencia global de infección oculta por el virus de la hepatitis B fue de 2,5 por ciento (18/709). No se encontró asociación significativa entre las variables analizadas.Conclusiones: la infección oculta por el virus de la hepatitis B fue frecuente en pacientes hemodializados con bajos niveles de anti-HBs, principalmente en aquellos con concentraciones no protectoras. Este estudio ratifica la necesidad de mantener la estrategia de prevención contra las hepatitis virales de transmisión parenteral en las unidades de diálisis(AU)


Introduction: occult hepatitis B virus infection is characterized by the presence of the viral genome and antibodies to the capside protein in serum or plasma (anti-HBc) that test negative for the infection marker.Objectives: to detect the occult hepatitis B virus in hemodialysis patients and to identify the possible relationship between occult hepatitis B infection and hepatitis C virus infection and the epidemiological and demographic variables.Methods: seventy thousand and nine serum samples from patients treated in 18 hemodialysis units were included. Serological markers for HBV infection, exposure and immunity were tested. Samples with negative HBsAg , positive anti-HBc and anti-HBs titers <50 IU/L were tested for detection of HBV-DNA and HCV markers.Results: the prevalence of HBV infection and exposure were 6.9 percent and 28.6 percent respectively. In the group, 4.3 percent of samples met occult hepatitis B infection criteria, the HBV-DNA was detected in 58.1 percent (18/31) of the samples, with viral loads below 105 IU/mL. Overall occult hepatitis B infection prevalence was 2.5 percent (18/709). There was no significant association among the analyzed variables.Conclusions: occult hepatitis B infection was frequent in hemodialysis patients with low levels of anti-HBs mainly in those with non protected titers. This study supports the need of keeping the prevention strategies against parenterally transmitted viral hepatitis in dialysis units(AU)


Assuntos
Humanos , Vírus da Hepatite B/isolamento & purificação , Diálise Renal/efeitos adversos , Hepatite B/epidemiologia , Epidemiologia Descritiva , Estudos Transversais , Hepatite C/sangue , Cuba
9.
J Med Virol ; 88(7): 1222-9, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27061406

RESUMO

Although hepatitis B virus (HBV) and human immunodeficiency virus (HIV) co-infection is common, only few data are available on HBV among HIV patients including occult hepatitis B infection (OBI), regardless of serological markers. This study aims to determine the prevalence of OBI and overall HBV infection, associated factors, HBV genotypes, and surface (S) gene mutations in a population of treatment-naïve HIV-infected patients in Brazil. A cross-sectional study was conducted in treatment-naïve HIV-infected patients in Central Brazil. All samples were tested for HBV serological markers and HBV DNA. Sequence analysis of the S gene and overlapping polymerase gene was preformed. Overall, 25.1% (127/505) of the patients had markers of current or previous HBV infection, which was associated with age over 40 years, history of injection drug use, and homosexual sex. The hepatitis B surface antigen (HBsAg) seroprevalence was 4.9% (25/505). HBV DNA was detected in 39 out of 505 patients: 20 of them were HBsAg-positive and 19 were HBsAg-negative, resulting in an OBI prevalence of 3.8%. Patients with OBI had significantly higher HCV seropositivity rate compared to HBsAg-positive patients. Sequencing of the S gene revealed Y100C, T131N, and D144A mutations. One patient had the M204I and L180M drug-resistance mutations (polymerase). HBV genotypes A (A1, A2), D (D2, D3), and F (F2) were identified. In conclusion, OBI represented almost half of all HBV infections with detectable HBV DNA, suggesting that hepatitis B diagnosis in HIV patients should include in addition to serological markers the detection of HBV DNA.


Assuntos
Coinfecção/epidemiologia , DNA Viral/sangue , Infecções por HIV/complicações , Hepatite B/epidemiologia , Hepatite B/virologia , Adolescente , Adulto , Idoso , Brasil/epidemiologia , Estudos Transversais , Usuários de Drogas , Feminino , Genótipo , Infecções por HIV/tratamento farmacológico , Infecções por HIV/virologia , Hepatite B/diagnóstico , Anticorpos Anti-Hepatite B/sangue , Antígenos de Superfície da Hepatite B/genética , Antígenos de Superfície da Hepatite B/imunologia , Vírus da Hepatite B/genética , Homossexualidade , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Valor Preditivo dos Testes , Prevalência , Estudos Soroepidemiológicos , Adulto Jovem
10.
J Virol Methods ; 223: 40-4, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26215428

RESUMO

The aim of the present study was to evaluate the performance of three in-house PCR techniques for HBV DNA detection and compare it with commercial quantitative methods to evaluate the usefulness of in-house methods for HBV diagnosis. Three panels of HBsAg reactive sera samples were evaluated: (i) 50 samples were examined using three methods for in-house qualitative PCR and the Cobas Amplicor HBV Monitor Assay; (ii) 87 samples were assayed using in-house semi-nested PCR and the Cobas TaqMan HBV test; (iii) 11 serial samples obtained from 2 HBV-infected individuals were assayed using the Cobas Amplicor HBV test and semi-nested PCR. In panel I, HBV DNA was detected in 44 samples using the Cobas Amplicor HBV test, 42 samples using semi-nested PCR (90% concordance with Cobas Amplicor), 22 samples using PCR for the core gene (63.6% concordance) and 29 samples using single-round PCR for the pre-S/S gene (75% concordance). In panel II, HBV DNA was quantified in 78 of the 87 HBsAg reactive samples using Cobas TaqMan but 52 samples using semi-nested PCR (67.8% concordance). HBV DNA was detected in serial samples until the 17th and 26th week after first donation using in-house semi-nested PCR and the Cobas Amplicor HBV test, respectively. In-house semi-nested PCR presented adequate concordance with commercial methods as an alternative method for HBV molecular diagnosis in low-resource settings.


Assuntos
DNA Viral/análise , Vírus da Hepatite B/isolamento & purificação , Hepatite B/diagnóstico , Hepatite B/virologia , Técnicas de Diagnóstico Molecular/métodos , Reação em Cadeia da Polimerase/métodos , Adulto , Idoso , DNA Viral/genética , Feminino , Vírus da Hepatite B/genética , Humanos , Masculino , Pessoa de Meia-Idade
11.
Rev. bras. pesqui. méd. biol ; Braz. j. med. biol. res;47(11): 990-994, 11/2014. tab, graf
Artigo em Inglês | LILACS | ID: lil-723905

RESUMO

Estimates of occult hepatitis B virus (HBV) infection prevalence varies among different studies depending on the prevalence of HBV infection in the study population and on the sensitivity of the assay used to detect HBV DNA. We investigated the prevalence of occult HBV infection in cirrhotic patients undergoing liver transplantation in a Brazilian referral center. Frozen liver samples from 68 adults were analyzed using a nested polymerase chain reaction assay for HBV DNA. The specificity of the amplified HBV sequences was confirmed by direct sequencing of the amplicons. The patient population comprised 49 (72.1%) males and 19 (27.9%) females with a median age of 53 years (range=18-67 years). Occult HBV infection was diagnosed in three (4.4%) patients. The etiologies of the underlying chronic liver disease in these cases were alcohol abuse, HBV infection, and cryptogenic cirrhosis. Two of the patients with cryptic HBV infection also presented hepatocellular carcinoma. Markers of previous HBV infection were available in two patients with occult HBV infection and were negative in both. In conclusion, using a sensitive nested polymerase chain reaction assay to detect HBV DNA in frozen liver tissue, we found a low prevalence of occult HBV infection in cirrhotic patients undergoing liver transplant, probably due to the low prevalence of HBV infection in our population.


Assuntos
Adolescente , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem , DNA Viral/isolamento & purificação , Vírus da Hepatite B/isolamento & purificação , Hepatite B Crônica/epidemiologia , Transplante de Fígado , Cirrose Hepática/virologia , Infecções Assintomáticas/epidemiologia , Biomarcadores , Brasil/epidemiologia , Carcinoma Hepatocelular/complicações , Vírus da Hepatite B/genética , Hepatite B Crônica/complicações , Hepatite Crônica/complicações , Hepatite Crônica/epidemiologia , Neoplasias Hepáticas/complicações , Reação em Cadeia da Polimerase , Prevalência , Centros de Atenção Terciária
12.
Liver Int ; 34(7): 991-1000, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25098191

RESUMO

Hepatitis B virus (HBV) is a very complex and intricate DNA structure associated with a particular genomic organization and replication cycle. However, many years of investigations allowed clarification of the real HBV natural history, through a deeper knowledge of the behavior of HBV antigens and viral structures. Several of the old diagnostic tools, such as HBV surface antigen (HBsAg) and HBV e antigen (HBeAg) determinations, gained prominence now, since the variation of both HBsAg and HBeAg plasma levels was shown to predict treatment response. In addition, the availability of more sensitive methods, such as HBV DNA detection by real-time PCR, has improved the current knowledge of the relationships between HBV replication levels and the natural history of the disease. It is now well established that some HBV genotypes are associated with a better response to treatment with pegylated interferon. Despite the widely accepted value of liver biopsy as a staging tool, transient elastography is being increasingly acknowledged as a non-invasive method to assess liver stiffness, chiefly for detection of advanced fibrosis. Current international guidelines for the management of chronic hepatitis B have provided several accurate biochemical and serological criteria for selecting patients for treatment, allowing a higher number of cases to be enrolled into antiviral therapy. This review describes the different serological markers used for the study of HBV and their clinical significance. It also deals with methods used for detection of genotypes and HBV DNA, emphasizing the effectiveness of such determinations for both patient selection and chronic hepatitis B therapy/monitoring.


Assuntos
Biomarcadores/sangue , Gerenciamento Clínico , Técnicas de Imagem por Elasticidade/métodos , Vírus da Hepatite B/metabolismo , Hepatite B Crônica/diagnóstico , Interleucinas/genética , Antígenos Virais/sangue , Genótipo , Vírus da Hepatite B/efeitos dos fármacos , Vírus da Hepatite B/genética , Hepatite B Crônica/tratamento farmacológico , Humanos , Interferon-alfa/farmacologia , Interferons , Polietilenoglicóis/farmacologia , Proteínas Recombinantes/farmacologia
13.
Vox Sang ; 107(1): 19-25, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24697276

RESUMO

BACKGROUND: Brazil requires the performance of both a test for hepatitis B surface antigen (HBsAg) and a test for antibodies to the core of hepatitis B for blood donor screening. Blood centres in regions of high HBV endemicity struggle to maintain adequate stocks in face of the high discard rates due to anti-HBc reactivity. We evaluated the potential infectivity of donations positive for anti-HBc in search of a rational approach for the handling of these collections. STUDY DESIGN AND METHODS: We tested anti-HBc reactive blood donations from the state of Amazonas for the presence of HBV DNA and for titres of anti-HBs. The study population consists of village-based donors from the interior of Amazonas state. RESULTS: Among 3600 donations, 799 were anti-HBc reactive (22·2%). We were able to perform real-time PCR for the HBV S gene on specimens from 291 of these donors. Eight of these samples were negative for HBsAg and positive for HBV DNA and were defined as occult B virus infections (2·7%). Six of those eight specimens had anti-HBs titres above 100 mIU/ml, indicating the concomitant presence of the virus with high antibody titres. CONCLUSION: A small proportion of anti-HBc reactive donors carry HBV DNA and anti-HBs testing is not useful for predicting viremia on them. This finding indicates the possibility of HBV transmission from asymptomatic donors, especially in areas of high HBV prevalence. Sensitive HBV DNA nucleic acid testing may provide another level of safety, allowing eventual use of anti-HBc reactive units in critical situations.


Assuntos
Doadores de Sangue , Transfusão de Sangue/métodos , Controle de Doenças Transmissíveis/métodos , Hepatite B/sangue , Hepatite B/epidemiologia , Adulto , Transfusão de Sangue/normas , Brasil/epidemiologia , DNA Viral/sangue , DNA Viral/isolamento & purificação , Anticorpos Anti-Hepatite B/sangue , Antígenos do Núcleo do Vírus da Hepatite B/imunologia , Antígenos de Superfície da Hepatite B/sangue , Vírus da Hepatite B/genética , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Reação em Cadeia da Polimerase em Tempo Real , Viremia/sangue
14.
Mem. Inst. Oswaldo Cruz ; 108(5): 657-660, ago. 2013. tab
Artigo em Inglês | LILACS | ID: lil-680763

RESUMO

In this cross-sectional study, 207 hepatitis B surface antigen (HBsAg)-negative kidney transplant recipients were evaluated based on demographic and epidemiological data and on the levels of serological markers of hepatitis B virus (HBV) and hepatitis C virus infection and liver enzymes. Patients with HBV or human immunodeficiency virus infection were excluded. Sera were analysed for the presence of HBV-DNA. HBV-DNA was detected in two patients (1%), indicating occult hepatitis B (OHB) infection (the HBV-DNA loads were 3.1 and 3.5 IU/mL in these patients). The results of the liver function tests were normal and no serological markers indicative of HBV infection were detected. The prevalence of OHB infection was low among kidney transplant recipients, most likely due to the low HBsAg endemicity in the general population of the study area.


Assuntos
Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Vírus da Hepatite B , Hepatite B/epidemiologia , Transplante de Rim , Brasil/epidemiologia , Estudos Transversais , DNA Viral/análise , Antígenos de Superfície da Hepatite B/sangue , Vírus da Hepatite B/genética , Vírus da Hepatite B/imunologia , Hepatite B/diagnóstico , Prevalência
15.
Braz. j. infect. dis ; Braz. j. infect. dis;16(6): 517-520, Nov.-Dec. 2012. tab
Artigo em Inglês | LILACS | ID: lil-658920

RESUMO

INTRODUCTION: Hepatitis B virus (HBV) infection is an important worldwide public health problem. In Brazil, the Ministry of Health estimates that 15% of the population has had contact with HBV, and that the mean rate of chronic carriers in Northeastern Brazil is around 0.5%. OBJECTIVE: The aim of this study was to assess the prevalence of HBV markers in pregnant women receiving prenatal care at the public maternity hospitals of São Luís. Methods: Demographical and epidemiological data were collected from 541 pregnant women according to the research protocol. Blood samples were collected, and the anti-HBc test was performed first. If positive, the sample was subsequently tested for HBsAg and anti-HBs. All HBsAg and/or anti-HBc positive samples were additionally tested for HBV-DNA. RESULTS: 40 (7.4%) pregnant women turned out positive for anti-HBc. Of those, five (0.9%) were HBsAg positive, four (0.7%) were anti-HBc positive with negative HBsAg and anti-HBs, and 31 (5.7%) were positive for anti-HBc and anti-HBs. Anti-HBc positivity was associated with family history of hepatitis and education level below 11 years of schooling. HBV-DNA was positive in only one HBsAg-positive sample. There was no HBV-DNA positivity among HBsAg negative samples. CONCLUSIONS: The prevalence of HBsAg in pregnant women in this study confirmed that São Luís is a low endemicity area. Occult hepatitis B was not detected in these samples.


Assuntos
Adulto , Feminino , Humanos , Gravidez , Adulto Jovem , Vírus da Hepatite B/imunologia , Hepatite B/epidemiologia , Complicações Infecciosas na Gravidez/epidemiologia , Brasil/epidemiologia , DNA Viral/sangue , Maternidades , Anticorpos Anti-Hepatite B/sangue , Antígenos do Núcleo do Vírus da Hepatite B/sangue , Antígenos de Superfície da Hepatite B/sangue , Vírus da Hepatite B/genética , Hepatite B/diagnóstico , Diagnóstico Pré-Natal , Complicações Infecciosas na Gravidez/diagnóstico , Fatores Socioeconômicos
16.
Mem. Inst. Oswaldo Cruz ; 107(6): 758-789, set. 2012. tab
Artigo em Inglês | LILACS | ID: lil-649495

RESUMO

Data concerning the relationship between hepatitis B virus (HBV) genotypes and liver histology are scarce. The aim of this study was to compare HBV non-B and non-C genotypes according to demographic features, clinical status, HBV-DNA levels and liver histology in Rio de Janeiro. One hundred twenty one consecutive chronic HBV-infected patients were enrolled during two-year period and data were prospectively collected. Sera were tested for HBV genotyping using restriction fragment length polymorphism. Liver biopsy was obtained from patients with either increased alanine aminotransferase (ALT) or HBV-DNA levels. Genotype A was the most common, found in 82 (68%) patients, followed by F in 19 (15%), D in 17 (14%), B in one (1%) and C in two (2%). There was no association between HBV genotypes A, D and F and gender (p = 0.37), age (p = 0.78), race (p = 0.22), mode of infection (p = 0.94), HB "e" antigen status (p = 0.37) and HBV-DNA levels (p = 0.47). The ALT levels were lower in genotype D (75%) compared with A (47%) and F (55%) (p = 0.05). Liver biopsy showed lower inflammation [histological activity index (HAI) = 4] and fibrosis (F) (= 0) scores in genotype D than in genotypes A (HAI = 5, p < 0.001; F = 2, p = 0.008) or F (HAI = 5, p = 0.009; F = 2, p = 0.01). Genotype A was the most prevalent in chronic HBV-infected patients and genotype D patients presented with less intense liver disease.


Assuntos
Adolescente , Adulto , Idoso , Criança , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem , DNA Viral/genética , Vírus da Hepatite B/genética , Hepatite B Crônica/virologia , Cirrose Hepática/virologia , Alanina Transaminase/análise , Brasil , Estudos Transversais , Fibrose , Genótipo , Hepatite B Crônica/patologia , Cirrose Hepática/patologia , Reação em Cadeia da Polimerase , Índice de Gravidade de Doença
17.
Rev. Soc. Bras. Med. Trop ; Rev. Soc. Bras. Med. Trop;45(4): 457-462, July-Aug. 2012. graf, mapas, tab
Artigo em Inglês | LILACS | ID: lil-646901

RESUMO

INTRODUCTION: Hepatitis B virus (HBV) infection is one of the most serious public health problems in the world. In Brazil, HBV endemicity is heterogeneous, with the highest disease prevalence in the North region. METHODS: A total of 180 samples were analyzed and subjected to polymerase chain reaction (PCR) and semi-nested PCR of the HBV S-gene, with the aim of determining the prevalence of HBV-DNA (deoxyribonucleic acid) in indigenous groups inhabiting the areas near the Curuçá and Itaquaí Rivers in the Javari Valley, State of Amazonas, Brazil. RESULTS: The prevalence of the HBV-DNA S-gene was 51.1% (92/180). The analysis found 18 of 49 (36.7%) samples from the Marubo tribe, 68 of 125 (54.4%) from the Kanamary, and 6 of 6 (100%) from other ethnic groups to be PCR positive. There was no statistically significant difference in gender at 5% (p=0.889). Indigenous people with positive PCR for HBV-DNA had a lower median age (p<0.001) of 23 years. There was no statistical difference found in relation to sources of contamination or clinical aspects with the PCR results, except for fever (p<0.001). The high prevalence of HBV-DNA of 75% (15/20) in pregnant women (p=0.009) demonstrates an association with vertical transmission. CONCLUSIONS: The results confirm the high prevalence of HBV-DNA in the Javari Valley, making it important to devise strategies for control and more effective prevention in combating the spread of HBV.


INTRODUÇÃO: A infecção pelo vírus da hepatite B (VHB) é um dos mais sérios problemas de saúde pública do mundo. No Brasil, a endemicidade do VHB é heterogênea, sendo a doença mais prevalente na região norte do país. MÉTODOS: Neste estudo, foram investigadas 180 amostras de sangue por meio da técnica da reação em cadeia da polimerase (PCR) e PCR semi-nested para o vírus da hepatite B, gene S, com o intuito de determinar a prevalência do DNA (ácido desoxirribonucléico) do vírus da hepatite B em povos de etnias indígenas habitantes dos Rios Curuçá e Itaquaí no Vale do Javari, Estado do Amazonas, Brasil. RESULTADOS: A prevalência encontrada para o DNA-VHB gene S foi de 51,1% (92/180). Entre as amostras positivas 18/49 (36,7%) pertenciam à etnia Marubo, 68/125 (54,4%) à Kanamary e 6/6 (100%) a outras etnias. Não houve diferença significante ao nível de 5% em relação ao gênero (p=0,889). Os indígenas com PCR positiva para DNA-VHB apresentaram mediana de idade menor de 23 anos (p<0,001). Não foi constatado nenhuma diferença estatística em relação às fontes de contágio e o resultado da PCR, como também aos aspectos clínicos, com exceção da febre (p<0,001). A alta prevalência do DNA-VHB de 75% (15/20) em gestantes (p=0,009) demonstra associação com a transmissão vertical. CONCLUSÕES: Os resultados comprovam a alta prevalência do DNA-VHB no Vale do Javari, tornando-se importante traçar estratégias de controle e prevenção mais eficazes no combate à disseminação do VHB.


Assuntos
Adolescente , Adulto , Idoso , Criança , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Gravidez , Adulto Jovem , DNA Viral/genética , Vírus da Hepatite B/genética , Hepatite B/epidemiologia , Indígenas Sul-Americanos/estatística & dados numéricos , Brasil/epidemiologia , Estudos Transversais , Reação em Cadeia da Polimerase , Prevalência
18.
Braz. j. infect. dis ; Braz. j. infect. dis;14(5): 519-525, Sept.-Oct. 2010. tab
Artigo em Inglês | LILACS | ID: lil-570570

RESUMO

The clinical and epidemiological importance of chronic B hepatitis is currently unquestionable as a cause of end-stage liver disease and hepatocellular carcinoma. Recently, predictors of treatment response of this disease have been studied, both before and during the course of medication. Therapy stopping rules have been proposed, which may be useful in patients presenting poor treatment tolerance. This review discusses the treatment response predictors usefulness, with emphasis on ALT, quantitative HBsAg and HBeAg, quantitative HBV-DNA and HBV genotype.


Assuntos
Humanos , Antivirais/uso terapêutico , Vírus da Hepatite B , Hepatite B Crônica/tratamento farmacológico , Interferon-alfa , Polietilenoglicóis/uso terapêutico , DNA Viral/análise , Genótipo , Antígenos de Superfície da Hepatite B/sangue , Antígenos E da Hepatite B/sangue , Vírus da Hepatite B/genética , Vírus da Hepatite B/imunologia , Hepatite B Crônica/virologia
19.
Rev. Inst. Med. Trop. Säo Paulo ; Rev. Inst. Med. Trop. Säo Paulo;52(3): 119-124, May-June 2010. ilus, tab
Artigo em Inglês | LILACS | ID: lil-550343

RESUMO

Hepatitis B virus (HBV) is a major cause of chronic liver disease worldwide. Besides genotype, quantitative analysis of HBV infection is extensively used for monitoring disease progression and treatment. Affordable viral load monitoring is desirable in resource-limited settings and it has been already shown to be useful in developing countries for other viruses such as Hepatitis C virus (HCV) and HIV. In this paper, we describe the validation of a real-time PCR assay for HBV DNA quantification with TaqMan chemistry and MGB probes. Primers and probes were designed using an alignment of sequences from all HBV genotypes in order to equally amplify all of them. The assay is internally controlled and was standardized with an international HBV panel. Its efficacy was evaluated comparing the results with two other methods: Versant HBV DNA Assay 3.0 (bDNA, Siemens, NY, USA) and another real-time PCR from a reference laboratory. Intra-assay and inter-assay reproducibilities were determined and the mean of CV values obtained were 0.12 and 0.09, respectively. The assay was validated with a broad dynamic range and is efficient for amplifying all HBV genotypes, providing a good option to quantify HBV DNA as a routine procedure, with a cheap and reliable protocol.


O vírus da Hepatite B (HBV) é uma das principais causas de doença crônica do fígado no mundo. Além do genótipo, a análise quantitativa do HBV é amplamente utilizada para monitorar a progressão da doença e o tratamento. Em locais com recursos escassos, métodos baratos para o monitoramento da carga viral são desejáveis e, em países em desenvolvimento, sua utilidade já foi demonstrada para outros vírus, como o da Hepatite C e HIV. Neste trabalho, descrevemos a validação de um teste de PCR em Tempo Real para a quantificação do DNA do HBV utilizando sondas Taqman/MGB. Os oligos e sondas foram escolhidos usando um alinhamento contendo seqüências de todos os genótipos do HBV para garantir uma amplificação igual de todos eles. O teste possui um controle interno e foi padronizado com um painel internacional de HBV. Sua eficácia foi testada comparando-se os resultados com outros dois métodos: Versant HBV DNA Assay 3.0 (bDNA, Siemens, NY, USA) e outro PCR em tempo real realizado em um laboratório de referência. As reprodutibilidades intra e inter-ensaio foram determinadas e a média dos valores de CV obtidos foram de 0,12 e 0,09, respectivamente. O teste foi validado com uma ampla faixa dinâmica e amplificou com eficiência os diferentes genótipos de HBV, fornecendo uma boa opção para a quantificação de rotina do DNA do HBV, com um protocolo barato e confiável.


Assuntos
Humanos , Primers do DNA/genética , DNA Viral/genética , Vírus da Hepatite B/genética , Hepatite B/virologia , Reação em Cadeia da Polimerase/métodos , DNA Viral/análise , Genótipo , Hepatite B/diagnóstico , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Carga Viral
20.
GEN ; 63(2): 103-105, jun. 2009. ilus, tab
Artigo em Espanhol | LILACS | ID: lil-664408

RESUMO

De acuerdo a consensos científicos a nivel internacional el objetivo primordial en el tratamiento de la hepatitis crónica B (HCB) es actualmete lograr la supresión de la replicación viral de manera potente y en el menor tiempo posible. A continuación presentamos la experiencia clínica acumulada en Venezuela empleando el análogo nucleosido telbivudina en pacientes con HCB. Se analizaron 29 portadores con HCB, promedio de edad 44±17 años, con una proporción 2/1 sexo masculino/sexo femenino, 23 con HCB antígeno e positivo y 6 con HCB antígeno e negativo. Las variables escogidas de evaluación fueron la viremia (ADN VHB), el valor de ALT y la tolerancia al tratamiento. Durante un período promedio de tratamiento de 7,3 meses cada paciente recibió 600 mg diarios de telbivudina. 86,2% de ellos disminuyó significativamente la carga circulante de ADN VHB de 7,3±1,2 log10 copias/mL a 1,9±1,0 log10 copias/mL (p= 0,0001). Adicionalmente, se demostró disminución significativa de los valores de ALT, de un promedio de 4,3 veces a una media de 1,4 veces el límite superior normal (p=0,01). Exceptuando un paciente con elevación importante de creatin-quinasa y otro que se quejó de sensación de acidez, la tolerancia reportada fue muy buena. Es concluyente que la telbivudina indujo supresión de la carga viral en forma potente y temprana tanto en pacientes con HCB antígeno e positivo como antígeno e negativo, mejoró los valores de ALT y fue bien tolerada la dosis por la mayoría. La reducción de la carga viral a niveles incluso indetectables durante el primer año de tratamiento, debería contribuir a prevenir la emergencia temprana de cepas del VHB resistentes a esta droga antiviral.


According to international scientific consensus, the fundamental goal in the treatment of chronic hepatitis B (CHB) is currently to achieve suppression of the viral replication in a very potent way at the shortest possible time. It follows our clinical experience accomplished in Venezuela by using the nucleoside analog telbivudine in patients with CHB. We studied twenty-nine carriers with CHB, mean age of 44±17 years old, male/female ratio 2/1, 23 of them with e antigen positive CHB and the remaining 6 with e antigen negative CHB. We selected the viral load (HBV DNA), the ALT value and the treatment tolerance as the parameters to be assessed. During an average treatment period of 7,3 months each patient received 600 mg daily of telbivudine. 86.2% of them showed significant decreased of the circulating HBV DNA load, from 7.3±1.2 log10 copies/mL to 1.9±1.0 log10 copies/mL (p= 0.0001). In addition, a significant decrease of ALT values from a mean of 4.3 fold to 1.4 fold (p=0.01) was also demonstrated. The group of patients showed very good tolerance of the doses, except one who presented increased creatine kinase value and another one who complained from peptic symptoms. It is conclusive that Telbivudine induced early and potent viral suppression, either in e antigen positive or e antigen negative CHB, improved the ALT values and was very well-tolerated by the majority. The viral load reduction, even undetectable during the first year of treatment, should contribute to prevent the early emergency of resistant strains to this antiviral drug.

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