Evaluación de una reacción en cadena de la polimerasa en tiempo real simple y rápida para la cuantificación del ADN del virus de la hepatitis B / Evaluation of a simple and fast real time polymerase chain reaction assay for quantification of hepatitis B virus DNA

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)

Assessment on the Effects of Hepatitis B Prevention and Control Measures in Western China: A Comparison of Three Population-based Serosurveys / 生物医学与环境科学（英文）

Objective@#Despite the remarkable progress in efforts to control disease spread, the nationwide elimination of hepatitis B in China is still hindered by the persistently high rate of hepatitis B virus (HBV) infection in Western China. This study aimed to evaluate the strategy of hepatitis B prevention and control in Western China and identify potential areas and strategies for improvement.@*Methods@#Susceptible population vaccination, health education, professional training of doctors, and other prevention and control measures have been implemented in Wuwei city since 2010. Data were obtained from three representative cross-sectional serosurveys conducted in 2010, 2013, and 2015. The serum samples were subjected to enzyme-linked immunosorbent assays to detect the following seromarkers: HBV surface antigen (HBsAg), antibody against hepatitis B surface antigen (anti-HBs), and antibody against hepatitis B core antigen (anti-HBc). Estimates of variance were determined using Taylor series linearization methods.@*Results@#The three serosurveys revealed decreases in the prevalence of HBsAg (7.19% in 2010 @*Conclusion@#Although vaccine-based prevention and control measures reduced the rate of HBV infection in Wuwei City over time, the hepatitis B infection rate in children younger than 10 years was still higher than the national average level. Therefore, the prevention and control of mother-to-child transmission and the management of the infected should be the focus of future prevention and control work.

Molecular and serological characterization of occult hepatitis B among blood donors in Maputo, Mozambique

BACKGROUND Occult hepatitis B virus (HBV) - characterized by the absence of detectable HBsAg in the presence of HBV DNA - represents a potential threat for blood safety. OBJECTIVES This study was conducted with the aim to investigate the serological and molecular characterization of occult HBV infection (OBI) among blood donors in Mozambique. METHODS 1,502 blood donors were tested for HBsAg. All HBsAg-negative individuals were tested for HBV DNA. Antibodies against HBV core, surface and HBe antigen (anti-HBc, anti-HBs, HBeAg) were measured in HBV DNA positive individuals. FINDINGS 1435 serum samples were HBsAg negative and 16 positive for HBV DNA, 14 confirmed to have OBI, corresponding to a frequency of 0.98%. Of the 14 OBI infections identified, 13/14 (92.8%) were positive for anti-HBc, 4/14 (28.5%) for anti-HBs, and no samples were reactive for HBeAg. Of the 14 OBI cases, nine samples (64.2%) were sequenced for the S/P region. Eight samples (88.9%) belonged to genotype A1 and one (11.1%) to genotype E. One escape mutation (T123A) associated with OBI and various amino acid substitutions for genotype A1 and E were observed. MAIN CONCLUSIONS Our results show the importance of using nucleic acid amplification test to detect occult hepatitis B infection in blood donors in Mozambique.

Hepatitis B viremia in HIV-coinfected individuals under antiretroviral therapy

ABSTRACT Background: Antiretroviral therapy (ART) has decreased AIDS incidence and mortality, rendering comorbidities, such as hepatitis B more relevant for people living with human immunodeficiency virus (HIV). Since antiretroviral drugs may also inhibit hepatitis B virus (HBV) replication, analyzing the impact of ART on management of hepatitis B in this population is important. Objective: To assess HBV viremia among HIV/HBV coinfected individuals on ART and its associated factors. Method: For this cross-sectional study, HIV/HBV-coinfected individuals, aged over 18 years, who were on ART for over six months and receiving care at an outpatient clinic in São Paulo were recruited. Sociodemographic characteristics, information about viral exposure, clinical and laboratory data, including evaluation of liver fibrosis were obtained. Plasma HBV DNA was measured by polymerase chain reaction. Viral genome sequencing was conducted for genotyping and identification of drug resistance-conferring mutations if viral load exceeded 900 IU/mL. Results: Out of 2,946 patients who attended the clinic in 2015, 83 were eligible and 56 evaluated. Plasma HBV DNA was detected in 16 (28.6%) (95% CI: 18.0-41.3%), all on lamivudine and tenofovir treatment. HBV DNA detection was associated with lower education (p = 0.015), higher international normalized ratios (p = 0.045), history of an AIDS-defining illness [OR: 3.43 (95% CI: 1.10-11.50)], and HBeAg detection [OR: 6.60 (95% CI: 1.84-23.6)]. In contrast, a last CD4+ count above 500 cells/mm3 in the year prior to inclusion [OR: 0.18 (95% CI: 0.04-0.71)] and detection of anti-HBe [OR: 0.21 (95% CI: 0.04-0.99)] were negatively associated. Patients with HBV DNA above 900 IU/mL were infected with subgenotypes A1 (n = 3) and D2 (n = 1), and exhibited viral mutations associated with total resistance to lamivudine and partial resistance to entecavir. Conclusions: Despite being on ART, a significant proportion of HIV/HBV-coinfected individuals present HBV viremia. Characterization of factors that are associated with this finding may help professionals provide better management to these patients.

Cribado de virus de hepatitis B en mujeres embarazadas: inmigrantes, y chilenas con conductas de riesgo. Manejo del binomio madre-hijo: Plan piloto / Screening of hepatitis B in high risk Chilean and immigrant pregnant women: management of mother to child transmission

Resumen Introducción: Chile es un país de baja endemia de virus de hepatitis B (VHB), pero los países de mayor flujo migratorio hacia Chile tienen una endemia intermediaalta. La inmunoprofilaxis (IP) en el recién nacido (RN) es fundamental para evitar la transmisión vertical de VHB. Objetivos: Determinar la prevalencia de HBsAg en mujeres embarazadas: inmigrantes, y chilenas con conductas de riesgo (CR), y evaluar el cumplimiento de la indicación de IP a los RN de madre con HBsAg reactivo. Material y Métodos: Cohorte prospectiva de cribado de HBsAg a mujeres embarazadas inmigrantes, y chilenas con CR, entre julio 2017 y junio 2018 en CABL. Los RN de madre con HBsAg reactivo se les administró IP adecuada (antes de 12 h de vida). Resultados: Se realizó un total de 1.415 HBsAg: 1.265 a inmigrantes y 150 a chilenas con CR. Se obtuvieron 37 pacientes con HBsAg reactivos. Dos falsos positivos. La prevalencia HBsAg en inmigrantes fue 2,7% y 0,66% en chilenas con CR (p < 0,05). El 91,1% provenía de Haití, con una prevalencia de 3,5% en nuestra área. Todos los RN (36) recibieron IP. La mediana de administración de IP fue 3:02 h. Conclusiones: La prevalencia de VHB en mujeres gestantes inmigrantes fue superior a lo reportado en la población general y en mujeres chilenas con CR. Planteamos la necesidad de implementar el cribado universal en el embarazo, y en especial, en mujeres embarazadas provenientes de países con endemia intermedia-alta.

Background: Chile is a low-endemic HBV country, but countries with the highest migratory flow to Chile have an intermediate-high endemicity. In order to avoid vertical transmission of HBV, immunoprophylaxis (IP) in the newborn (NB) is a key factor. Aim: To identify HBsAg prevalence in pregnant immigrants and Chilean pregnant women with risk behaviors (RB) and to asses IP use in the NB. Material and Methods: Prospective HBsAg screening cohort of immigrant and Chilean pregnant women with RB, between July 1, 2017 and June 30, 2018 in CABL. IP of all NB of reactive HBsAg mothers was assessed. Results: 1,415 HBsAg samples, 1,265 immigrants and 150 Chileans with RB. 37 reactive HBsAg. Two false positive. HBsAg prevalence in immigrant pregnant women was 2.7% and 0.66% in Chileans with RB (p < 0.05). 91.1% came from Haiti, with a prevalence of 3.5% in our region. All NB (36) received IP with a median of administration of 3:02 h. Conclusions: The prevalence in immigrant pregnant women was higher than that reported in the general population and in Chilean women with RB. We proposed the need for universal screening in pregnancy, especially in pregnant women from countries with intermediate-high endemicity.

A Study of the Association between Diabetes Mellitus and Chronic Hepatitis B Virus Infection / Un Estudio de la Asociación entre la Diabetes Mellitus y la Infección Crónica por el Virus de la Hepatitis B

ABSTRACT Background: Hepatitis B virus (HBV) infection and diabetes mellitus are major health problems associated with significant morbidity and mortality. The published literature suggests an association of diabetes mellitus with liver disease. However, the role of HBV infection in diabetes aetiology is still controversial. The present study was conducted to explore the veracity of this enigmatic association among Pakistani subjects. Methodology: The blood samples and clinical information were collected from chronic HBV-positive patients Group 1 (n = 120), and their age and gender were matched with those of the healthy control subjects Group 2 (n = 120). Hepatitis B virus-positive patients were also subdivided into two groups; (Group 1a and Group 1b) with and without liver cirrhosis for evaluation of the prevalence of diabetes. Results: The study revealed that there were statistically significant differences in the biochemical parameters in the HBV-positive and control groups. There was no correlation between diabetes and HBV with the prevalence of diabetes mellitus being similar in subjects with and without HBsAg (11.7% in the positive group and 10% in the controls). Since there were a relatively large number (32.5%) of HBV-positive patients with liver cirrhosis, a comparison of biochemical parameters was also carried out to evaluate the extent of the liver damage and its association with diabetes. During the comparison of HBV patients with and without cirrhosis for the prevalence of diabetes, no aetiologic association was found with diabetes. Conclusion: Study revealed that there was no correlation between HBV infection and diaabetes despite the significantly different biochemical parameters in the HBV-infected group and control subjects.

RESUMEN Antecedentes: La infección por el virus de la hepatitis B (VHB) y la diabetes mellitus son problemas de salud importantes asociados con morbilidad y mortalidad significativas. La literatura publicada sugiere una asociación de la diabetes mellitus con las enfermedades hepáticas. Sin embargo, el papel de la infección por VHB en la etiología de diabetes sigue siendo contro-versial. El presente estudio fue conducido con el propósito de explorar la veracidad de esta enigmática asociación entre sujetos paquistaníes. Metodología: Se recogieron muestras de sangre e información clínica de pacientes crónicos VHB positivos Grupo 1 (n = 120), y su edad y género fueron comparados con los de los sujetos sanos del control Grupo 2 (n = 120). Los pacientes positivos al virus de la hepatitis B también se subdividieron en dos grupos, a saber, (Grupo 1a y Grupo 1b) con y sin cirrosis hepática en relación con la prevalencia de la diabetes. Resultados: El estudio reveló que hubo diferencias significativas en estos dos grupos en los parámetros bioquímicos entre el grupo de control y el grupo VHB positivo. En estos dos grupos no hubo correlación entre la diabetes y el VHB. Puesto que hubo un número relativamente grande (32.5%) de pacientes VHB positivos con cirrosis hepática, se realizó también una comparación de los parámetros bioquímicos a fin de comprender el grado del daño hepático y su asociación con la diabetes. Durante la comparación de los pacientes con VHB con y sin cirrosis en relación con la prevalencia de diabetes, no se halló asociación etiológica con la diabetes. Conclusión: Este estudio reveló que no hubo correlación entre la infección por VHB y la diabetes, a pesar de los parámetros bioquímicos significativamente diferentes entre el grupo infectado por el VHB y los sujetos del control.

Cloning and high-level expression of Thermus thermophilus RecA in E. coli: purification and novel use in HBV diagnostics

ABSTRACT We studied the role of Thermus thermophilus Recombinase A (RecA) in enhancing the PCR signals of DNA viruses such as Hepatitis B virus (HBV). The RecA gene of a thermophilic eubacterial strain, T. thermophilus, was cloned and hyperexpressed in Escherichia coli. The recombinant RecA protein was purified using a single heat treatment step without the use of any chromatography steps, and the purified protein (>95%) was found to be active. The purified RecA could enhance the polymerase chain reaction (PCR) signals of HBV and improve the detection limit of the HBV diagnosis by real time PCR. The yield of recombinant RecA was ∼35 mg/L, the highest yield reported for a recombinant RecA to date. RecA can be successfully employed to enhance detection sensitivity for the diagnosis of DNA viruses such as HBV, and this methodology could be particularly useful for clinical samples with HBV viral loads of less than 10 IU/mL, which is interesting and novel.

Novel fluoronucleoside analog NCC inhibits lamivudine-resistant hepatitis B virus in a hepatocyte model

ABSTRACT Antiviral drug resistance is the most important factor contributing to treatment failure using nucleos(t)ide analogs such as lamivudine for chronic infection with hepatitis B virus (HBV). Development of a system supporting efficient replication of clinically resistant HBV strains is imperative, and new antiviral drugs are needed urgently to prevent selection of drug-resistant HBV mutants. A novel fluorinated cytidine analog, NCC (N-cyclopropyl-4′-azido-2′-deoxy-2′-fluoro-β-d-cytidine), was recently shown to strongly inhibit human HBV in vitro and in vivo. This study was designed to evaluate the antiviral activity of NCC against lamivudine-resistant HBV. We generated a stable cell line encoding the major pattern of lamivudine-resistant mutations rtL180M/M204V and designated it "HepG2.RL1". Immuno-transmission electron microscopic examination and enzyme-linked immunosorbent assay were used to detect secretion of HBV-specific particles and antigens. Quantification of extracellular DNA and intracellular DNA of HepG2.RL1 cells by quantitative real-time polymerase chain reaction revealed >625-fold and >5556-fold increases in the 50% inhibitory concentration of lamivudine, respectively, compared with that for the wild-type virus. The results showed that NCC inhibited DNA replication and HBeAg production in wild-type or lamivudine-resistant HBV in a dose-dependent manner. In conclusion, screening for antiviral compounds active against lamivudine-resistant HBV can be carried out with relative ease using hepG2.RL1 cells. NCC is a potential antiviral agent against wild-type HBV and clinical lamivudine-resistant HBV and deserves evaluation for the treatment of HBV infection.

Detection of occult hepatitis B in serum and oral fluid samples

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.

Prevalencia del virus de la inmunodeficiencia humana, virus de la hepatitis B y Treponema pallidum en reclusos del Centro de Detención Preventiva de Arica, Chile / Prevalence of HIV, hepatitis B virus and Treponema pallidum in inmates in the Preventive Detention Center of Arica, Chile

Resumen Introducción: Los grupos de riesgo para las infecciones de transmisión sexual (ITS) son trabajadores sexuales, drogadictos, la población joven de inicio sexual precoz, así como la población penal. Objetivo: Determinar la prevalencia de infección por virus de inmunodeficiencia humana (VIH), Treponema pallidum y virus de hepatitis B (VHB) en reclusos (hombres) del Centro de Detención Preventiva (CDP) de Arica. Material y Métodos: El estudio se efectuó en 140 reclusos, con consentimiento informado. Se realizó encuesta epidemiológica y toma de muestra sanguínea. Los exámenes positivos se enviaron al Hospital Regional de Arica para confirmación y posteriormente al Instituto de Salud Pública. Resultados: La prevalencia de ITS fue de 13,6%. La mayor frecuencia se observó en VDRL positivos (7,1%), seguido por infección por VIH (5,7%) y VHB (2,9%). Por edad, la mayor frecuencia (57,9%) se presentó en individuos bajo 31 años. El 63,2% se encontraban en situación de hacinamiento, en 42,1% la edad de inicio de la actividad sexual fue antes de los 15 años y 94,7% declaró ser consumidor de drogas. Conclusiones: El estudio reafirma los factores predisponentes a la transmisión de las ITS, como edad, inicio sexual precoz, consumo de drogas y hacinamiento, destacando que las prisiones son ambientes altamente vulnerables, donde la sobrepoblación, condición sexual, inicio sexual precoz, alto consumo de drogas y la carente visita conyugal proporcionan un contexto epidemiológico favorable para el incremento de ITS.

Background: The risk groups for sexual transmitted diseases (STDs) are sex workers, drug addicts, young people in early sexual initiation, and population in prison. Aim: To determine the prevalence of HIV, Treponema pallidum and hepatitis B Virus (HBV) in male inmates at the Preventive Detention Center (CDP) of Arica. Methods: The study was conducted in 140 inmates, with informed consent. Epidemiological survey and blood sampling was conducted. The positive tests were sent to the Hospital Regional of Arica for confirmation and the National Reference Laboratory for confirmation. Results: STD prevalence was 13.6%. The most prevalent was VDRL positive (7.1%) followed by HIV infection (5.7%) and HBV (2.9%). The highest rate (57.9%) occurred in individuals under 31 years old. 63.2% were in an overcrowded situation, 42.1% of cases corresponded to those whose age of sexual activity onset of was before age 15 and 94.7% used drugs. Conclusions: The study reasserts the predisposing factors for the transmission of STDs as age, early sexual debut, drug abuse and overcrowding, noting that prisons are highly vulnerable environments where overcrowding, sexual condition, early sexual initiation, high drug abuse and the lacking spouses visits provide an epidemiological context favorable for increased STD.

Prevalence, risk factors and hepatitis B immunization: helping fill the gap on hepatitis B epidemiology among homeless people, Goiânia, Central Brazil / Prevalência, fatores de risco e imunização contra a hepatite B: ajudando a preencher as lacunas na epidemiologia da hepatite B entre pessoas em situação de rua em Goiânia, Goiás, Brasil / Prevalencia, factores de riesgo e inmunización contra la hepatitis B: ayudando a completar las lagunas en la epidemiología de la hepatitis B entre personas sin techo en Goiânia, Goiás, Brasil

Data are limited in Brazil on hepatitis B infection among homeless individuals, a marginalized population with high risk of sexually transmissible infections (STI), including hepatitis B. The aim of this study was to investigate hepatitis B epidemiology in homeless persons lodged in a public shelter in Goiânia, Central Brazil. From August 2014 to June 2015, 353 individuals were interviewed and tested for markers of HBV infection. Overall HBV prevalence was 21.8% (95%CI: 17,82-26,41), and 19,5% (95%CI: 15,75-24,0) showed a serological profile of previous HBV vaccination. Older individuals (> 50 years), blacks, and homosexuals or bisexuals showed increased exposure to HBV. The low frequency of individuals immunized against HBV, high social vulnerability, and risk behaviors emphasize the need for health services administrators to provide more opportunities for HBV vaccination in this target population.

No Brasil, existem poucos dados sobre a infecção por hepatite B entre pessoas em situação de rua, uma população marginalizada com alto risco para infecções sexualmente transmissíveis (IST), incluindo a hepatite B. O objetivo deste estudo foi investigar a epidemiologia da hepatite B em pessoas alojadas em um abrigo público da cidade de Goiânia, Brasil Central. De agosto de 2014 a junho de 2015, 353 indivíduos foram entrevistados e testados para os marcadores da infecção pelo HBV. Uma prevalência global de 21,8% (IC95%: 17,82-26,41) para HBV foi estimado, e 19,5% (IC95%: 15,75-24,0) apresentaram perfil sorológico de vacinação prévia contra o HBV. Ser mais velho (acima de 50 anos de idade), preto e homossexual ou bissexual foram preditores de exposição ao HBV. A baixa frequência de indivíduos imunizados contra o HBV, bem como de alta vulnerabilidade social e ocorrência de comportamentos de risco reforçam a necessidade dos gestores de saúde proporcionar mais oportunidades de vacinação para esta população-alvo.

En Brasil, existen pocos datos sobre la infección por hepatitis B entre personas sin techo, una población marginalizada con un alto riesgo de infecciones sexualmente transmisibles (IST), incluyendo la hepatitis B. El objetivo de este estudio fue investigar la epidemiología de la hepatitis B en personas alojadas en un albergue público de la ciudad de Goiânia, Brasil Central. De agosto de 2014 a junio de 2015, se entrevistó a 353 individuos y se probaron los marcadores de la infección por HBV. Se estimó una prevalencia global de un 21,8% (IC95%: 17,82-26,41) para HBV, y 19,5% (IC95%: 15,75-24,0) presentaron un perfil serológico de vacunación previa contra el HBV. Ser más viejo (por encima de 50 años de edad), negro y homosexual o bisexual fueron predictores de exposición al HBV. La baja frecuencia de individuos inmunizados contra el HBV, así como la alta vulnerabilidad social y ocurrencia de comportamientos de riesgo refuerzan la necesidad de los gestores de salud de proporcionar más oportunidades de vacunación para esta población-objetivo.

Infección oculta por el virus de la hepatitis B en pacientes hemodializados cubanos / Occult hepatitis B virus infection in hemodialysis patients

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)

Prevalence of occult hepatitis b infection in iranian cancer patients before chemotherapy treatment / Prevalência de infecção oculta da hepatite B em pacientes iranianos com câncer antes do tratamento de quimioterapia

ABSTRACT Background Occult hepatitis B infection is characterized by negative hepatitis B surface antigen (HBsAg) and also detectable hepatitis B virus (HBV) -DNA, with or without hepatitis B core antibody (anti-HBc). HBV reactivation in individuals under immunosuppressive therapy is critical, occurring in occult HBV. Objective In this study, we aimed to determine the prevalence of occult HBV infection among hepatitis B surface antigen negative in cancer patients before receiving chemotherapy. Methods Sera from 204 cancer patients who were negative for HBsAg, were tested for anti-HBc antibodies. The samples that were negative for HBsAg but positive for anti-HBc also examined for HBV-DNA by polymerase chain reaction (PCR). Results Of the 204 HBsAg negative blood samples, 11 (5.4%) samples were positive for anti-HBc antibodies. HBV-DNA was detected in 9/11 (81%) of anti-HBc positive samples. Occult HBV infection in hematological cancers was more than solid cancers, 4.8% and 4.3% respectively. There was no significant difference in HBc antibody positivity based on vaccination, previous blood transfusions, history of familial hepatitis or biochemical parameters (ALT, AST, total and direct bilirubin levels) (P>0.05). Conclusion Screening of occult HBV infection by HBsAg, HBV DNA and anti HB core antibody should be suggested as a routine investigation in cancer patients before receiving chemotherapy.

RESUMO Contexto A infecção oculta da hepatite B caracteriza-se por antígeno de superfície da hepatite B (AgHBs) negativo com vírus detectável da hepatite B (HBV) -DNA, com ou sem anticorpo de núcleo da hepatite B (anti-HBc). A reativação do HBV em indivíduos sob terapia imunossupressora é crítica, originando a infecção oculta pelo VHB. Objetivo Este estudo teve como objetivo determinar a prevalência de infecção oculta pelo VHB entre em pacientes com câncer e com antígeno de superfície da hepatite B negativo antes de receber quimioterapia. Métodos Soro de 204 pacientes com câncer que foram negativos para AgHBs, foram testados para anticorpos anti-HBc. As amostras que foram negativos para AgHBs, mas positivo para anti-HBc foram também examinadas para HBV-DNA, por reação em cadeia da polimerase. Resultados Entre 204 amostras de sangue AgHBs negativas, 11 (5,4%) foram positivos para anticorpos anti-HBc. HBV-DNA foi detectado em 9/11 (81%) das amostras positivas de anti-HBc. Infecção oculta de VHB em câncer hematológico foi maior que em cânceres sólidos, 4,8% e 4,3% respectivamente. Não houve diferença significativa na positividade anti-HBc, com base na vacinação, transfusões de sangue anteriores, história de hepatite familiar ou parâmetros bioquímicos (ALT, AST, total e níveis de bilirrubina total) (P & gt; 0,05). Conclusão A triagem de infecção oculta por AgHBs, HBV-DNA e anti-anticorpo de núcleo HB deve ser sugerida como uma investigação de rotina em pacientes com câncer antes de receber a quimioterapia.

An in-house real-time polymerase chain reaction: standardisation and comparison with the Cobas Amplicor HBV monitor and Cobas AmpliPrep/Cobas TaqMan HBV tests for the quantification of hepatitis B virus DNA

This study aimed to standardise an in-house real-time polymerase chain reaction (rtPCR) to allow quantification of hepatitis B virus (HBV) DNA in serum or plasma samples, and to compare this method with two commercial assays, the Cobas Amplicor HBV monitor and the Cobas AmpliPrep/Cobas TaqMan HBV test. Samples from 397 patients from the state of São Paulo were analysed by all three methods. Fifty-two samples were from patients who were human immunodeficiency virus and hepatitis C virus positive, but HBV negative. Genotypes were characterised, and the viral load was measure in each sample. The in-house rtPCR showed an excellent success rate compared with commercial tests; inter-assay and intra-assay coefficients correlated with commercial tests (r = 0.96 and r = 0.913, p < 0.001) and the in-house test showed no genotype-dependent differences in detection and quantification rates. The in-house assay tested in this study could be used for screening and quantifying HBV DNA in order to monitor patients during therapy.

Occult hepatitis B virus infection in liver transplant patients in a Brazilian referral center

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.

Individual donor nucleic acid testing for blood safety against HIV-1 and hepatitis B and C viruses in a tertiary care hospital.

Background. In July 2010, we started universal individual donor nucleic acid testing (ID-NAT) at our blood bank. This test simultaneously detects human immunodeficiency virus-1 (HIV-1), hepatitis B virus (HBV) and hepatitis C virus (HCV) in samples of donor blood. We continued to do the enzymelinked immunosorbent assay (ELISA) test for these agents, as per the guidelines of the Drug Controller General of India. We assessed the impact of ID-NAT in preventing transfusionassociated transmission of viruses. Methods. We used fourth generation ELISA to screen blood samples of all voluntary and replacement blood donors. ID-NAT was done by transcription-mediated amplification (TMA). Results. Of the 18 356 donors, ID-NAT could not be performed on 2 samples which were inadequate. Of the 18 354 donors tested by both ID-NAT and fourth generation ELISA, 7 were found to be NAT-positive but ELISA-negative (NAT yield) for HBV and HCV. The prevalence of NAT yield cases among routine donors was 1 in 2622 donations tested (0.038%). Since we supply blood as components (packed red cells, fresh frozen plasma and platelet concentrate), these 7 units of blood would have yielded 21 components and hence 21 patients could have been infected with HBV and HCV viruses. Conclusion. In the vast majority of blood units tested, the results of ELISA and ID-NAT for HIV-1, HBV and HCV were concordant. ID-NAT did detect the presence of viruses missed by ELISA in some blood units. It widespread use in blood banks would ensure safer blood transfusion.

Sangre segura en ausencia de infecciones virales por VHB, VHC y VIH en período de ventana serológica de donadores

OBJETIVO: Determinar la prevalencia de infecciones virales (VHB, VHC y VIH) en período de ventana serológica en donadores de sangre evaluados con la prueba de ácidos nucleicos (NAT). MATERIALES Y MÉTODOS: Se incluyeron donadores de sangre evaluados de 2008 a 2009 con pruebas serológicas y moleculares del VHB, VHC y VIH. El período de ventana serológica se definió con la prueba de NAT positiva y la prueba serológica negativa. RESULTADOS: Durante un año se evaluaron 47 847 donadores de sangre; no se identificó ningún caso con infección viral (VHB, VHC y VIH) en período de ventana serológica; únicamente se demostró NAT positivo en donadores con pruebas serológicas positivas: 26 de 78 con VHB, 56 de 318 con VHC y 16 de 155 con VIH. CONCLUSIÓN: Este es el primer estudio en México que demostró en donadores de sangre la ausencia de infecciones virales (VHB, VHC y VIH) en período de ventana serológica con la prueba de NAT.

OBJECTIVE: To determine the prevalence of viral infections (HBV, HCV and HIV) in serological window period in blood donors screened with nucleic acid testing (NAT). MATERIALS AND METHODS: We assessed all blood donors from July 2008 to June 2009 at the Central Blood Bank of the Mexican Institute of Social Security. Medical history was made and provided an information brochure and self-exclusion questionnaire. All blood donors were tested with serological tests (Ag-HBVs, Anti-HCV and Anti-HIV) and molecular testing with NAT for HBV, HCV and HIV. The window period was defined with the positive NAT and negative serological test. RESULTS: During one year, we evaluated 47 847 blood donors. None subject was identified with viral infection (HBV, HCV and HIV) in serological window period. Positive serological testing were found for HBV in 78 (0.2 percent), 318 (0.7 percent) for HCV and 155 (0.3 percent) for HIV. Positive NAT was demonstrated only in donors with positive serology: 26 of 78 with HBV, 56 of 318 with HCV and 16 of 155 with HIV. CONCLUSION: This is the first study in México showed no viral infections (HBV, HCV and HIV) during serological window period in blood donors; The medical history and the self-exclusion questionnaire help to improve blood transfusion safety.

Hepatitis C and hepatitis B seroprevalence and associated risk factors in hemodialysis patients in Guilan province, north of Iran

Hepatitis C virus [HCV] and hepatitis B virus [HBV] infection are especially problematic in patients with end-stage renal disease who are undergoing hemodialysis [HD]. To determine the prevalence of HCV and HBV infection in HD population in Guilan, north of Iran. In a cross-sectional study, from May to September 2009, in 11 different hemodialysis units in Guilan province, North of Iran, clinical data such as age, gender, duration of dialysis, HBsAg and anti-HCV antibody of 514 HD patients were recorded. Patients with positive antibodies against HCV were tested for HCV RNA. From 514 patients, 286 [55.64%] were male. 61 [11.9%] patients were anti-HCV-positive and 31 [50.8%] were HCV PCR-positive. There was significant relationship between HCV Ab-positivity with gender and HD duration [p<0.05]. There was significant difference between the mean HD duration in anti-HCV-positive and anti-HCV-negative patients [p<0.05]. Also, significant relationship was found between HCV RNA-positivity with gender and HD duration [p< 0.05]. Seven [1.4%] patients were positive for HBsAg. Two [0.38%] were found positive for both HBsAg and anti-HCV antibody. There is low a prevalence of HCV and HBV in HD patients in our region. The rate can be decreased by HBV vaccination of end-stage renal disease patients before setting chronic HD, antiviral treatment and isolation of infected individuals