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1.
Med.lab ; 26(4): 353-364, 2022. Grafs, Tabs
Artigo em Espanhol | LILACS | ID: biblio-1412446

RESUMO

Introducción. La seguridad transfusional es el objetivo primordial de los bancos de sangre, sin embargo, conlleva un alto riesgo de eventos adversos como son las infecciones transmisibles por transfusión (ITT). El conocimiento de la prevalencia de estas infecciones fue de particular interés en esta investigación, donde se determinó su frecuencia, coinfección y relación con el tipo de donantes admitidos. Metodología. Estudio observacional retrospectivo de 2017 y 2018, en el que se incluyeron todos los registros de donantes de sangre que contenían datos demográficos y resultados de los marcadores obligatorios en el país (Ecuador), tanto de pruebas serológicas como moleculares. Se obtuvo el permiso del custodio de la información y del subcomité de bioética de investigaciones en seres humanos. Para el análisis de los datos se utilizó estadística descriptiva e inferencial. Resultados. Se determinó una prevalencia del 3,18 % de resultados reactivos para una o más ITT, el rango de edad más prevalente fue de 29 a 40 años, el 89,8 % fueron donantes compensatorios, y de ellos el 90 % fueron reactivos para una o más ITT. El marcador serológico más prevalente fue el anti-core del virus de la hepatitis B (anti-HBc), seguido por el de sífilis y los anticuerpos contra el virus de la hepatitis C (VHC). La coinfección más prevalente fue con sífilis y hepatitis B. Se encontró una diferencia estadísticamente significativa entre los resultados obtenidos en las pruebas serológicas y las moleculares (x2=26,9; p=0,000). Conclusión. Las ITT en los bancos de sangre son un riesgo latente, por lo que es necesario conocer las variaciones epidemiológicas que existen en cada población. El conocimiento de la prevalencia de las ITT en donantes de sangre permite establecer nuevas estrategias de selección del donante, que garanticen la mejor seguridad posible en las transfusiones, además debe verificarse siempre la metodología utilizada y hacer monitoreo permanente del sistema de calidad establecido


Introduction. Transfusion safety is the primary objective of blood banks, however one of the adverse reactions to blood transfusion are the transfusion transmissible infections (TTIs). Knowledge of the prevalence of these infections was of particular interest in this study where we determined their frequency, co-infection and relationship with the type of donors admitted. Methodology. Retrospective observational study during 2017 and 2018, in which all blood donor records containing demographic data and results of the country's (Ecuador) mandatory serological markers of both serological and molecular tests were included. Permission was obtained from the data custodian and the Human Research Bioethics Subcommittee. Descriptive and inferential statistics were used for data analysis. Results. A prevalence of 3,18% of reactive results to one or more TTIs was determined, the most prevalent age range was 29 to 40 years, 89.8% were compensatory donors and 90% of them were reactive to one or more TTIs. The anti- core serological marker of the hepatitis B virus (anti-HBc) was the most prevalent, followed by syphilis and hepatitis C antibodies. Syphilis and hepatitis B were identified as the most prevalent coinfection. The correlation between the results obtained in the serological and molecular tests was determined to be different and statistically significant (x2=26.9; p=0.000). Conclusion. TTIs in blood banks are a latent risk, so it is necessary to know the epidemiological variations that exist in every population. Knowledge of the prevalence of TTIs in blood donors facilitates new donor selection strategies that guarantee the best possible safety in transfusions. In addition, the methodology used must always be verified and the established quality system must be permanently monitored


Assuntos
Humanos , Masculino , Feminino , Adolescente , Adulto , Pessoa de Meia-Idade , Idoso , Adulto Jovem , Doadores de Sangue , Transfusão de Sangue , Infecções Transmitidas por Sangue/epidemiologia , Sífilis/sangue , Sífilis/epidemiologia , Estudos Soroepidemiológicos , Prevalência , Estudos Retrospectivos , Hepatite C/sangue , Hepatite C/epidemiologia , Hepatite B/sangue , Hepatite B/epidemiologia , Antígenos do Núcleo do Vírus da Hepatite B/sangue
2.
Transfusion ; 61(5): 1495-1504, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33687074

RESUMO

BACKGROUND: The present study determined the HBV antigen, antibody, and DNA status in blood donations deemed to be HBV positive. Individuals with an occult HBV infection (OBI), defined as being positive for HBV DNA but negative for HBV surface antigen (HBsAg), as well as those with active infection (HBsAg-positive), were identified and characterized. STUDY DESIGN AND METHODS: From a total pool if 198,363 blood donations, we evaluated in a cross-sectional study, 1106 samples that were positive in screening tests for antibody to HBV core antigen (HBcAb), HBsAg, and/or HBV DNA by nucleic acid testing (NAT-HBV). The presence of genetic variants in the HBV pol/S gene in individuals with an active HBV infection was also determined. RESULTS: OBIs were detected in six of 976 samples (0.6%) that were positive only for HBcAb. The rate of HBV active infection was 0.024% (48/198,363) and there was a predominance of HBV sub-genotype A1 (62.2%, 28/45), followed by D3 (17.8%, 8/45). Mutations in the S gene were found in 57.8% (26/45) and immune escape mutations in 37.8% (17/45) of active HBV-infected donors. Among them, T123N, G145A, and D144G high-impact immune escape mutations were identified. CONCLUSION: Highly sensitive molecular tests improve the capacity to detect OBIs. When NAT is performed in pooled samples, HBcAb test has value in the detection of donors with OBI and improves transfusion safety. Mutations in the S gene are frequent in HBsAg-positive blood, including those associated with diagnostic failure and vaccine escape mutations.


Assuntos
Doadores de Sangue , Segurança do Sangue , Seleção do Doador , Vírus da Hepatite B/isolamento & purificação , Hepatite B/sangue , Adulto , Brasil , Estudos Transversais , DNA Viral/sangue , Feminino , Anticorpos Anti-Hepatite B/sangue , Antígenos do Núcleo do Vírus da Hepatite B/sangue , Antígenos de Superfície da Hepatite B/sangue , Humanos , Masculino , Pessoa de Meia-Idade
3.
Hepatology ; 74(1): 99-115, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33458844

RESUMO

BACKGROUND AND AIMS: The hepatitis B core-related antigen (HBcrAg), a composite antigen of precore/core gene including classical hepatitis B core protein (HBc) and HBeAg and, additionally, the precore-related antigen PreC, retaining the N-terminal signal peptide, has emerged as a surrogate marker to monitor the intrahepatic HBV covalently closed circular DNA (cccDNA) and to define meaningful treatment endpoints. APPROACH AND RESULTS: Here, we found that the woodchuck hepatitis virus (WHV) precore/core gene products (i.e., WHV core-related antigen [WHcrAg]) include the WHV core protein and WHV e antigen (WHeAg) as well as the WHV PreC protein (WPreC) in infected woodchucks. Unlike in HBV infection, WHeAg and WPreC proteins were N-glycosylated, and no significant amounts of WHV empty virions were detected in WHV-infected woodchuck serum. WHeAg was the predominant form of WHcrAg, and a positive correlation was found between the serum WHeAg and intrahepatic cccDNA. Both WHeAg and WPreC antigens displayed heterogeneous proteolytic processing at their C-termini, resulting in multiple species. Analysis of the kinetics of each component of the precore/core-related antigen, along with serum viral DNA and surface antigens, in HBV-infected chimpanzees and WHV-infected woodchucks revealed multiple distinct phases of viral decline during natural resolution and in response to antiviral treatments. A positive correlation was found between HBc and intrahepatic cccDNA but not between HBeAg or HBcrAg and cccDNA in HBV-infected chimpanzees, suggesting that HBc can be a better marker for intrahepatic cccDNA. CONCLUSIONS: In conclusion, careful monitoring of each component of HBcrAg along with other classical markers will help understand intrahepatic viral activities to elucidate natural resolution mechanisms as well as guide antiviral development.


Assuntos
Vírus da Hepatite B da Marmota/imunologia , Vírus da Hepatite B/imunologia , Hepatite B/imunologia , Animais , Biópsia , DNA Viral/isolamento & purificação , Glicosilação , Hepatite B/sangue , Hepatite B/virologia , Antígenos do Núcleo do Vírus da Hepatite B/sangue , Antígenos do Núcleo do Vírus da Hepatite B/imunologia , Antígenos do Núcleo do Vírus da Hepatite B/metabolismo , Vírus da Hepatite B da Marmota/genética , Vírus da Hepatite B da Marmota/isolamento & purificação , Vírus da Hepatite B da Marmota/patogenicidade , Antígenos E da Hepatite B/sangue , Antígenos E da Hepatite B/imunologia , Antígenos E da Hepatite B/metabolismo , Vírus da Hepatite B/genética , Vírus da Hepatite B/isolamento & purificação , Vírus da Hepatite B/patogenicidade , Fígado/patologia , Fígado/virologia , Marmota , Pan troglodytes
4.
Rev Soc Bras Med Trop ; 53: e20180533, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31994654

RESUMO

INTRODUCTION: HBV and HIV have identical transmission routes. The aim of this study was to determine the prevalence of HBV in HIV patients and to detect the presence of occult HBV infection. METHODS: All samples were tested for serology markers and using qPCR. RESULTS: This study included 232 individuals, out of which 36.6% presented with HBV markers and 11.8% presented with HBsAg or HBV-DNA, including 3 patients that showed OBI. CONCLUSIONS: We observed a high prevalence of HBV among HIV patients. In addition, the results suggest that OBI can occur in patients with serological profiles that are indicative of past infection. Therefore, the application of molecular tests may enable the identification of infections that are not evident solely based on serology.


Assuntos
Infecções por HIV/epidemiologia , 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/imunologia , Hepatite B/epidemiologia , Brasil/epidemiologia , DNA Viral/sangue , Infecções por HIV/complicações , Hepatite B/complicações , Hepatite B/diagnóstico , Humanos , Prevalência , Reação em Cadeia da Polimerase em Tempo Real
5.
Rev. Soc. Bras. Med. Trop ; 53: e20180533, 2020. tab
Artigo em Inglês | LILACS | ID: biblio-1057270

RESUMO

Abstract INTRODUCTION: HBV and HIV have identical transmission routes. The aim of this study was to determine the prevalence of HBV in HIV patients and to detect the presence of occult HBV infection. METHODS: All samples were tested for serology markers and using qPCR. RESULTS: This study included 232 individuals, out of which 36.6% presented with HBV markers and 11.8% presented with HBsAg or HBV-DNA, including 3 patients that showed OBI. CONCLUSIONS: We observed a high prevalence of HBV among HIV patients. In addition, the results suggest that OBI can occur in patients with serological profiles that are indicative of past infection. Therefore, the application of molecular tests may enable the identification of infections that are not evident solely based on serology.


Assuntos
Humanos , Infecções por HIV/epidemiologia , Vírus da Hepatite B/imunologia , Hepatite B/epidemiologia , Anticorpos Anti-Hepatite B/sangue , Antígenos do Núcleo do Vírus da Hepatite B/sangue , Antígenos de Superfície da Hepatite B/sangue , Brasil/epidemiologia , DNA Viral/sangue , Infecções por HIV/complicações , Prevalência , Reação em Cadeia da Polimerase em Tempo Real , Hepatite B/complicações , Hepatite B/diagnóstico
6.
PLoS One ; 14(10): e0222835, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31574098

RESUMO

BACKGROUND: Guyana expanded its HIV response in 2005 but the epidemiology of hepatitis B virus (HBV) and hepatitis C virus (HCV) infections has not been characterized. METHODS: The 2011 Seroprevalence and Behavioral Epidemiology Risk Survey for HIV and STIs collected biologic specimens with demographic and behavioral data from a representative sample of Guyana military personnel. Diagnostics included commercial serum: HIV antibody; total antibody to hepatitis B core (anti-HBc); IgM anti-HBc; hepatitis B surface antigen (HBsAg); anti-HBs; antibody to HCV with confirmatory testing; and HBV DNA sequencing with S gene fragment phylogenetic analysis. Chi-square, p-values and prevalence ratios determined statistical significance. RESULTS: Among 480 participants providing serologic specimens, 176 (36.7%) tested anti-HBc-positive. Overall, 19 (4.0%) participants tested HBsAg-positive; 17 (89.5%) of the HBsAg-positive participants also had detectable anti-HBc, including 1 (5.3%) IgM anti-HBc-positive male. Four (6.8%) females with available HBV testing were HBsAg-positive, all aged 23-29 years. Sixteen (16, 84.2%) HBsAg-positive participants had sufficient specimen for DNA testing. All 16 had detectable HBV DNA, 4 with viral load >2x104IU/ml. Sequencing found: 12 genotype (gt) A1 with 99.9% genetic identity between 1 IgM anti-HBc-positive and 1 anti-HBc-negative; 2 gtD1; and 2 with insufficient specimen. No statistically significant associations between risk factors and HBV infection were identified. CONCLUSIONS: Integrated HIV surveillance identified likely recent adult HBV transmission, current HBV infection among females of reproductive age, moderate HBV infection prevalence (all gtA1 and D1), no HCV infections and low HIV frequency among Guyana military personnel. Integrated HIV surveillance helped characterize HBV and HCV epidemiology, including probable recent transmission, prompting targeted responses to control ongoing HBV transmission and examination of hepatitis B vaccine policies.


Assuntos
Infecções por HIV/sangue , HIV-1/isolamento & purificação , Hepatite B/sangue , Hepatite C/sangue , Adolescente , Adulto , Região do Caribe/epidemiologia , Feminino , Guiana/epidemiologia , Anticorpos Anti-HIV/sangue , Infecções por HIV/epidemiologia , Infecções por HIV/transmissão , Infecções por HIV/virologia , HIV-1/patogenicidade , Hepatite B/epidemiologia , Hepatite B/transmissão , Hepatite B/virologia , 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/isolamento & purificação , Vírus da Hepatite B/patogenicidade , Hepatite C/epidemiologia , Hepatite C/transmissão , Hepatite C/virologia , Humanos , Masculino , Militares , Fatores de Risco , Estudos Soroepidemiológicos , Carga Viral , Adulto Jovem
7.
Rev Soc Bras Med Trop ; 52: e20180132, 2019 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-31141041

RESUMO

INTRODUCTION: Medical students have an occupational risk for hepatitis B (HB). This study sought to determine anti-HBs and anti-HBc IgG levels in vaccinated students, check their seroconversion, and correlate this with vaccination. METHODS: One hundred and forty-three students' blood samples and their vaccination schedules were analyzed. RESULTS: 65.7% were positive for anti-HBs; however, anti-HBs was absent in 34.3%. Only two samples were positive for anti-HBc IgG. CONCLUSIONS: More than 30% of students did not have minimum protective levels. Comparing HBV vaccination and anti-HBs reactivity, the majority of reactive individuals received their last dose within the past 16 years.


Assuntos
Vacinas contra Hepatite B/imunologia , Vírus da Hepatite B/imunologia , Hepatite B/prevenção & controle , Estudantes de Medicina , Adolescente , Adulto , Estudos Transversais , Feminino , Anticorpos Anti-Hepatite B/sangue , Anticorpos Anti-Hepatite B/imunologia , Antígenos do Núcleo do Vírus da Hepatite B/sangue , Antígenos do Núcleo do Vírus da Hepatite B/imunologia , Antígenos de Superfície da Hepatite B/sangue , Antígenos de Superfície da Hepatite B/imunologia , Humanos , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Masculino , Adulto Jovem
8.
Rev. Soc. Bras. Med. Trop ; 52: e20180132, 2019. tab
Artigo em Inglês | LILACS | ID: biblio-1041500

RESUMO

Abstract INTRODUCTION Medical students have an occupational risk for hepatitis B (HB). This study sought to determine anti-HBs and anti-HBc IgG levels in vaccinated students, check their seroconversion, and correlate this with vaccination. METHODS One hundred and forty-three students' blood samples and their vaccination schedules were analyzed. RESULTS: 65.7% were positive for anti-HBs; however, anti-HBs was absent in 34.3%. Only two samples were positive for anti-HBc IgG. CONCLUSIONS More than 30% of students did not have minimum protective levels. Comparing HBV vaccination and anti-HBs reactivity, the majority of reactive individuals received their last dose within the past 16 years.


Assuntos
Humanos , Masculino , Feminino , Adolescente , Adulto , Adulto Jovem , Estudantes de Medicina , Vírus da Hepatite B/imunologia , Vacinas contra Hepatite B/imunologia , Hepatite B/prevenção & controle , Imunoglobulina G/imunologia , Imunoglobulina G/sangue , Estudos Transversais , Anticorpos Anti-Hepatite B/imunologia , Anticorpos Anti-Hepatite B/sangue , Antígenos do Núcleo do Vírus da Hepatite B/imunologia , Antígenos do Núcleo do Vírus da Hepatite B/sangue , Antígenos de Superfície da Hepatite B/imunologia , Antígenos de Superfície da Hepatite B/sangue
9.
Colloids Surf B Biointerfaces ; 172: 272-279, 2018 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-30173094

RESUMO

An electrochemical immunosensor devoted the core hepatitis B antibody detection, based on polytyramine (PTy) and carbon nanotubes (CNT) composite was developed. The antibody interactions with immobilized antigens were detected by reduction on the electron transfer from ionic species coming from reactive amine groups of PTy. The synthesis in acid medium of PTy-CNT composite favorite a great amount of NH3+ ionic species, forming a nanocomposite with high catalytic activity on the electrode surface. As proof-of-concept, antibodies against the core hepatitis B virus were label-free and reagentless electrochemically detected by square wave voltammetry (SWV) through decrease on cathodic peaks. It was recently reported that hepatitis B core antigen antibodies (anti-HBc) is a powerful biomarker for hepatitis B virus (HBV) infection, being more specific than HBsAg due to the possibility of detecting the occult HBV infections. The nanostructured film was characterized by atomic force microscopy and electrochemical techniques. This immunosensor showed linear responses from 1.0 to 5.0 ng mL-1 and a limit of detection of 0.89 ng mL-1 anti-HBc. It was also tested in assays with negative and positive blood samples using 0.1 M KCl as electrolyte support on readings showing specific responses. This easy reagentless detection platform, showing a remarkable potential to development of bolder and simpler HBV assay for screening of blood bags, in attempting to circumvent point-of-care testing limitations.


Assuntos
Técnicas Eletroquímicas/métodos , Anticorpos Anti-Hepatite B/imunologia , Antígenos do Núcleo do Vírus da Hepatite B/análise , Eletrodos , Anticorpos Anti-Hepatite B/sangue , Antígenos do Núcleo do Vírus da Hepatite B/sangue , Humanos , Imunoensaio , Indicadores e Reagentes , Microscopia de Força Atômica , Nanotubos de Carbono/química , Espectroscopia de Infravermelho com Transformada de Fourier , Coloração e Rotulagem , Tiramina/química
10.
J Med Virol ; 89(12): 2149-2157, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-28792071

RESUMO

Hepatitis B virus (HBV) infection may be underestimated among high-risk individuals in regions of low HBs antigenemia. This study aimed to assess HBV serological markers, genotypes, and risk factors in Mexican patients with risk of HBV infection and low socioeconomic status. Demographics, clinical, and risk factor data were collected in patients with HIV (n = 289), HCV (n = 243), deferred blood donors (D-BD) (n = 83), and two native populations, Mixtecos (n = 57) and Purepechas (n = 44). HBV infection was assessed by HBsAg, anti-HBc, and HBV-DNA testing. Overall, patients had low education and very-low income. Totally, HBsAg prevalence was 16.5% (113/684) ranging from 0.7% (HCV) to 37.3% (D-BD), while anti-HBc was 30.2% (207/684). Among 52 sequences, genotypes H (n = 34, 65.4%), G (n = 4, 7.7%), subgenotypes F1b (n = 7, 13.5%), A2 (n = 6, 11.5%), and D4 (n = 1, 1.9%) were detected. Surgeries, sexual promiscuity, and blood transfusions had a differential pattern of distribution. In HCV patients, single (OR = 5.84, 95%Cl 1.91-17.80, P = 0.002), MSM (OR = 4.80, 95%Cl 0.75-30.56, P = 0.097), and IDU (OR = 2.93, 95%CI 1.058-8.09, P = 0.039) were predictors for HBV infection. While IDU (OR = 2.68, 95%CI 1.08-6.61, P = 0.033) and MSM (OR = 2.64, 95%CI 1.39-5.04, P = 0.003) were predictors in HIV patients. In this group, MSM was associated with HBsAg positivity (OR = 3.45, 95%CI 1.48-8.07, P = 0.004) and IDU with anti-HBc positivity (OR = 5.12, 95%CI 2.05-12.77, P < 0.001). In conclusion, testing with a combined approach of three different HBV markers, a high prevalence of HBV infection, a differential distribution of HBV genotypes, including subgenotypes F1b, A2, and D4, as well as risk factors in low-income Mexican risk groups were detected.


Assuntos
Doadores de Sangue , Vírus da Hepatite B/genética , Hepatite B/epidemiologia , Hepatite B/virologia , Classe Social , Adolescente , Adulto , Idoso , Estudos Transversais , DNA Viral/sangue , Feminino , Genótipo , Infecções por HIV/epidemiologia , Infecções por HIV/virologia , Hepatite B/etnologia , 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/classificação , Vírus da Hepatite B/isolamento & purificação , Humanos , Masculino , México/epidemiologia , Pessoa de Meia-Idade , Prevalência , Fatores de Risco , Adulto Jovem
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