RESUMO
In the last decade, a declining prevalence of HCV infection has been described in injecting drug users (IDUs) in different countries. This study is the first to assess temporal trends in drug-injecting patterns, HCV infection rates and viral genotype distribution in 770 Brazilian IDUs, recruited by two cross-sectional studies (1994-1997 and 1999-2001). A substantial decline in the prevalence of HCV infection was found over the years (75% in 1994 vs. 20.6% in 2001, P<0.001) that may be a consequence of the significant reduction in the overall frequencies of drug injection and needle-sharing, as well as the participation of IDUs in initiatives aimed at reducing drug-related harm. No trend was found in terms of viral genotype distribution. Despite the favourable scenario, preventive measures must be maintained, especially in vulnerable subgroups such as young or new injectors, where risky behaviours through direct and indirect sharing practices remain common.
Assuntos
Hepacivirus/genética , Hepatite C/epidemiologia , Hepatite C/virologia , Abuso de Substâncias por Via Intravenosa/complicações , Adulto , Brasil/epidemiologia , Estudos Transversais , Feminino , Variação Genética , Genótipo , Humanos , Masculino , Epidemiologia Molecular , Prevalência , Fatores de Risco , Comportamento Sexual , Fatores SocioeconômicosRESUMO
Since the identification of hepatitis C virus (HCV) in 1989 as a causative agent for a number of the extrahepatic alterations related to HCV infection an underlying immune mediated pathogenetic mechanism has been postulated. HCV-associated thrombocytopenia may be considered complex and multifactorial in origin, since different mechanisms have been implicated in its pathophysiology. With respect to autoimmune thrombocytopenia in chronic HCV infection, the detection of specific antibodies against platelet glycoproteins have been reported only in a few studies, but no systematic study has been carried out. We examined the clinical, laboratory, and virological characteristics of a case series of 10 patients with autoimmune thrombocytopenia (platelet count <150.0 x 10(9)/L) related to chronic HCV infection. Cases, six males and four females, aged 57.1 +/- 12.6 years, presented high titers of antibodies against platelet glycoprotein (GP) IIb/IIIa, GP Ia/IIa, and/or GP Ib/IX, and no other mechanism involved in the pathogenesis of HCV-associated thrombocytopenia was identified. Furthermore, cases were not associated with particular HCV genotype. Complete platelet response was observed in two patients treated with pegylated interferon plus ribavirin, and partial platelet response was seen in two patients treated with anti-D Ig and one patient treated with corticosteroids. These findings indicate that an autoimmune mechanism may play a role in the pathogenesis of HCV-associated thrombocytopenia in a proportion of these patients.
Assuntos
Anemia Hemolítica Autoimune/virologia , Hepatite C Crônica/sangue , Adulto , Idoso , Anemia Hemolítica Autoimune/sangue , Anticorpos/sangue , Anticorpos/imunologia , Antivirais/uso terapêutico , Quimioterapia Combinada , Feminino , Hepatite C Crônica/tratamento farmacológico , Humanos , Interferon alfa-2 , Interferon-alfa/uso terapêutico , Masculino , Pessoa de Meia-Idade , Contagem de Plaquetas , Glicoproteínas da Membrana de Plaquetas/imunologia , Polietilenoglicóis , Estudos Prospectivos , Proteínas Recombinantes , Ribavirina/uso terapêuticoRESUMO
The present study examined the distribution of hepatitis C virus (HCV) genotypes and subtypes in a hemodialysis population in Goiás State, Central Brazil, and evaluated the efficiency of two genotyping methods: line probe assay (LiPA) based on the 5' noncoding region and nucleotide sequencing of the nonstructural 5B (NS5B) region of the genome. A total of 1095 sera were tested for HCV RNA by RT-nested PCR of the 5' noncoding region. The LiPA assay was able to genotype all 131 HCV RNA-positive samples. Genotypes 1 (92.4%) and 3 (7.6%) were found. Subtype 1a (65.7%) was the most prevalent, followed by subtypes 1b (26.7%) and 3a (7.6%). Direct nucleotide sequencing of 340 bp from the NS5B region was performed in 106 samples. The phylogenetic tree showed that 98 sequences (92.4%) were classified as genotype 1, subtypes 1a (72.6%) and 1b (19.8%), and 8 sequences (7.6%) as subtype 3a. The two genotyping methods gave concordant results within HCV genotypes and subtypes in 100 and 96.2% of cases, respectively. Only four samples presented discrepant results, with LiPA not distinguishing subtypes 1a and 1b. Therefore, HCV genotype 1 (subtype 1a) is predominant in hemodialysis patients in Central Brazil. By using sequence analysis of the NS5B region as a reference standard method for HCV genotyping, we found that LiPA was efficient at the genotype level, although some discrepant results were observed at the subtype level (sensitivity of 96.1% for subtype 1a and 95.2% for subtype 1b). Thus, analysis of the NS5B region permitted better discrimination between HCV subtypes, as required in epidemiological investigations.
Assuntos
Regiões 5' não Traduzidas/genética , Hepacivirus/classificação , Hepatite C/virologia , Análise de Sequência de DNA/métodos , Proteínas não Estruturais Virais/genética , Sequência de Bases , DNA Viral/análise , Genótipo , Hepacivirus/genética , Hepatite C/diagnóstico , Humanos , Dados de Sequência Molecular , Reação em Cadeia da Polimerase/métodos , Diálise RenalRESUMO
The present study examined the distribution of hepatitis C virus (HCV) genotypes and subtypes in a hemodialysis population in Goiás State, Central Brazil, and evaluated the efficiency of two genotyping methods: line probe assay (LiPA) based on the 5' noncoding region and nucleotide sequencing of the nonstructural 5B (NS5B) region of the genome. A total of 1095 sera were tested for HCV RNA by RT-nested PCR of the 5' noncoding region. The LiPA assay was able to genotype all 131 HCV RNA-positive samples. Genotypes 1 (92.4 percent) and 3 (7.6 percent) were found. Subtype 1a (65.7 percent) was the most prevalent, followed by subtypes 1b (26.7 percent) and 3a (7.6 percent). Direct nucleotide sequencing of 340 bp from the NS5B region was performed in 106 samples. The phylogenetic tree showed that 98 sequences (92.4 percent) were classified as genotype 1, subtypes 1a (72.6 percent) and 1b (19.8 percent), and 8 sequences (7.6 percent) as subtype 3a. The two genotyping methods gave concordant results within HCV genotypes and subtypes in 100 and 96.2 percent of cases, respectively. Only four samples presented discrepant results, with LiPA not distinguishing subtypes 1a and 1b. Therefore, HCV genotype 1 (subtype 1a) is predominant in hemodialysis patients in Central Brazil. By using sequence analysis of the NS5B region as a reference standard method for HCV genotyping, we found that LiPA was efficient at the genotype level, although some discrepant results were observed at the subtype level (sensitivity of 96.1 percent for subtype 1a and 95.2 percent for subtype 1b). Thus, analysis of the NS5B region permitted better discrimination between HCV subtypes, as required in epidemiological investigations.
Assuntos
Humanos , /genética , Hepacivirus/classificação , Hepatite C/virologia , Análise de Sequência de DNA/métodos , Proteínas não Estruturais Virais/genética , Sequência de Bases , DNA Viral/análise , Genótipo , Hepacivirus/genética , Hepatite C/diagnóstico , Dados de Sequência Molecular , Reação em Cadeia da Polimerase/métodos , Diálise RenalRESUMO
Fourteen hepatitis C virus (HCV) chronically infected patients were submitted to routine liver biopsy for histological evaluation. Liver samples were assayed to HCV-RNA by in situ hybridization, using digoxigenin labeled probe. HCV genotypes were found to be predominantly type 1 (71.4%), followed by genotype 3 (21.4%), and genotype 2 (7.2%). Alanine-aminotransferase levels were raised in 10 patients. The histopathological scores were minimal (21.4%), mild (57.2%), and moderate (21.4%). Viral RNA was detected in liver cells from nine patients (64.3%). ISH method provides localization and poor confirmation of HCV RNA in the liver tissue of HCV chronic patients.
Assuntos
Hepacivirus/genética , Hepatite C Crônica/virologia , Hibridização In Situ/métodos , Fígado/virologia , RNA Viral/isolamento & purificação , Adulto , Idoso , Alanina Transaminase/sangue , Biópsia , Digoxigenina , Feminino , Formaldeído , Genótipo , Hepacivirus/isolamento & purificação , Hepatite C Crônica/patologia , Humanos , Fígado/patologia , Masculino , Pessoa de Meia-Idade , Inclusão em Parafina , Polimorfismo de Fragmento de Restrição , RNA Viral/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Índice de Gravidade de DoençaRESUMO
Fourteen hepatitis C virus (HCV) chronically infected patients were submitted to routine liver biopsy for histological evaluation. Liver samples were assayed to HCV-RNA by in situ hybridization, using digoxigenin labeled probe. HCV genotypes were found to be predominantly type 1 (71.4 percent), followed by genotype 3 (21.4 percent), and genotype 2 (7.2 percent). Alanine-aminotransferase levels were raised in 10 patients. The histopathological scores were minimal (21.4 percent), mild (57.2 percent), and moderate (21.4 percent). Viral RNA was detected in liver cells from nine patients (64.3 percent). ISH method provides localization and poor confirmation of HCV RNA in the liver tissue of HCV chronic patients.
Assuntos
Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Hepacivirus/genética , Hepatite C Crônica/virologia , Hibridização In Situ/métodos , Fígado/virologia , RNA Viral/isolamento & purificação , Alanina Transaminase/sangue , Biópsia , Digoxigenina , Formaldeído , Genótipo , Hepacivirus/isolamento & purificação , Hepatite C Crônica/patologia , Fígado/patologia , Inclusão em Parafina , Polimorfismo de Fragmento de Restrição , Reação em Cadeia da Polimerase Via Transcriptase Reversa , RNA Viral/genética , Índice de Gravidade de DoençaRESUMO
Hepatitis B virus (HBV) genotype A has been divided recently into two subgroups, designated A-A' (genotype A excluding A') and A'. Isolates belonging to subgroup A' have been identified in Africa. A new genotyping method, based on PCR amplification of the pre-S/S genome region and subsequent restriction fragment length polymorphism (RFLP) analysis, was developed, that established a correlation between RFLP subtypes and subgroups within genotype A. To investigate the occurrence of subgroup A' in South America, 119 Brazilian HBV isolates were analyzed. Ninety-three (78%) of them belonged to genotype A, with three predominating RFLP subtypes: 44 (37%) isolates were classified as AI, 30 (25%) were AII, and 18 (15%) were AIII. Pre-S/S nucleotide sequences of 15 genotype A isolates were determined. Phylogenetic analysis performed with these 15 and an additional 41 sequences revealed that isolates AI and AII clustered in subgroup A', whereas isolates AIII were classified into subgroup A-A'. The correlation RFLP subtypes-subgroups was confirmed by the presence of amino acid residues specific for subgroup A' in the surface antigens and polymerase of isolates AI and AII. The high proportion (63%) of isolates from subgroup A' suggested an African origin for a large number of Brazilian HBVs.
Assuntos
Vírus da Hepatite B/classificação , Vírus da Hepatite B/genética , Hepatite B/virologia , Aminoácidos/análise , Brasil/epidemiologia , Impressões Digitais de DNA , DNA Viral/análise , DNA Viral/química , DNA Viral/isolamento & purificação , Genes Virais , Genótipo , Hepatite B/epidemiologia , Vírus da Hepatite B/isolamento & purificação , Humanos , Epidemiologia Molecular , Dados de Sequência Molecular , Filogenia , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Análise de Sequência de DNA , Proteínas do Envelope Viral/química , Proteínas do Envelope Viral/genéticaRESUMO
The presence of hepatitis B virus (HBV) serological markers was investigated in 170 patients (137 male, 33 female) infected with human immunodeficiency virus (HIV) type 1. Antibodies to the hepatitis B core antigen (anti-HBc antibodies) were detected in 115 (68%) patients. Of these 115, 14 (12%) were hepatitis B surface antigen (HBsAg) positive, 60 (52%) presented anti-HBs antibodies, and 41 (35%) were anti-HBc positive only. All 115 of the anti-HBc positive samples were tested for HBV DNA by using two polymerase chain reaction (PCR) assays that amplify the core and pre-S regions of the HBV genome, respectively. HBV DNA was detected in 23 samples: 7 of 14 (50%) HBsAg-positive samples, 12 of 60 (20%) anti-HBs-positive samples, and 4 of 41 (10%) samples positive for anti-HBc only. Six samples (all HBsAg positive) were positive in both PCR assays and 17 samples were HBV DNA positive in only one assay. The mean viral load in HBsAg-positive patients was higher than that observed in HBsAg-negative patients. A number of patients were receiving treatment with lamivudine, a drug that interferes with both HBV and HIV replication. However, neither the rate of HBV DNA positivity nor HBV load was significantly different between patients treated with lamivudine and those not treated with this drug.
Assuntos
DNA Viral/análise , Infecções por HIV/epidemiologia , HIV-1/isolamento & purificação , Hepatite B/epidemiologia , Adulto , Distribuição por Idade , Brasil/epidemiologia , Distribuição de Qui-Quadrado , Estudos de Coortes , Comorbidade , Ensaio de Imunoadsorção Enzimática , Feminino , Seguimentos , Infecções por HIV/diagnóstico , Hepatite B/diagnóstico , Anticorpos Anti-Hepatite B/análise , Humanos , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Prevalência , Probabilidade , Fatores de Risco , Testes Sorológicos/métodos , Distribuição por Sexo , Carga ViralRESUMO
Viral hepatitis constitutes a major health issue, with high prevalence among injecting drug users (IDUs). The present study assessed the prevalence and risk determinants for hepatitis B, C and D viruses (HBV, HCV and HDV) infections among 102 IDUs from Rio de Janeiro, Brazil. Serological markers and HCV-RNA were detected by enzyme immunoassay and nested PCR, respectively. HCV genotyping was determined by restriction fragment length polymorphism analysis (RFLP). HBsAg, anti-HBc and anti-HBs were found in 7.8, 55.8 and 24.7 percent of IDUs, respectively. In the final logistic regression, HBV infection was independently associated with male homosexual intercourse within the last 5 years (odds ratio (OR) 3.1; 95 percent confidence interval (CI) 1.1-8.8). No subject presented anti-delta (anti-HD). Anti-HCV was detected in 69.6 percent of subjects, and was found to be independently associated with needle sharing in the last 6 months (OR 3.4; 95 percent CI 1.3-9.2) and with longer duration of iv drug use (OR 3.1; 95 percent CI 1.1-8.7). These data demonstrate that this population is at high risk for both HBV and HCV infection. Among IDUs from Rio de Janeiro, unprotected sexual intercourse seems to be more closely associated with HBV infection, whereas HCV is positively correlated with high risk injecting behavior. Comprehensive public health interventions targeting this population and their sexual partners must be encouraged
Assuntos
Humanos , Feminino , Adulto , Hepatite B/epidemiologia , Hepatite C/epidemiologia , Hepatite D/epidemiologia , Abuso de Substâncias por Via Intravenosa/epidemiologia , Brasil/epidemiologia , Estudos Epidemiológicos , Genótipo , Prevalência , Fatores de Risco , Comportamento Sexual , Fatores SocioeconômicosRESUMO
Hepatitis C virus (HCV) infection is widespread and responsible for more than 60 percent of chronic hepatitis cases. HCV presents a genetic variability which has led to viral classification into at least 6 genotypes and a series of subtypes. These variants present characteristic geographical distribution, but their association with different responses to treatment with interferon and severity of disease still remains controversial. The aim of this study was to investigate the patterns of distribution of HCV genotypes among different exposure categories in Brazil. Two hundred and fifty anti-HCV positive samples were submitted to HCV-RNA detection by RT-PCR and their genotype was determined by restriction fragment length polymorphism (RFLP) analysis. In addition, the genotype/subtype of 60 samples was also determined by a reverse hybridization assay. HCV 1 was the most prevalent (72.0 percent), followed by type 3 (25.3 percent), HCV 2 (2.0 percent) and HCV 4 (0.7 percent). The HCV genotype distribution varied among the different exposure categories, with HCV 1 being more frequent among blood donors, hemophiliacs and hemodialysis patients. A high frequency of HCV 3 was observed in cirrhotic patients, blood donors from the South of Brazil and injecting drug users (IDUs). The general distribution of the HCV genotype in Brazil is similar to that in other regions of the world