The influence of hepatitis B virus (HBV) genotypes in the natural history of the disease and its response to antiviral treatment have been addressed in many studies. In Brazil, studies on HBV genotype circulation have been restricted to specific population groups and states. Here, we have conducted a nationwide multicentre study with an unprecedented sample size representing all Brazilian regions in an effort to better understand the viral variants of HBV circulating among chronic carriers. Seven HBV genotypes were found circulating in Brazil. Overall, HBV/A was the most prevalent, identified in 589 (58.7 %) samples, followed by HBV/D (23.4 %) and HBV/F (11.3 %). Genotypes E, G, C and B were found in a minor proportion. The distribution of the genotypes differed markedly from the north to the south of the country. While HBV/A was the most prevalent in the North (71.6 %) and Northeast (65.0 %) regions, HBV/D was found in 78.9 % of the specimens analysed in the South region. HBV/F was the second most prevalent genotype in the Northeast region (23.5 %). It was detected in low proportions (7 to 10 %) in the North, Central-West and Southeast regions, and in only one sample in the South region. HBV/E was detected in all regions except in the South, while monoinfection with HBV/G was found countrywide, with the exception of Central-West states. Our sampling covered 24 of the 26 Brazilian states and the Federal District and is the first report of genotype distribution in seven states. This nationwide study provides the most complete overview of HBV genotype distribution in Brazil to date and reflects the origin and plurality of the Brazilian population.
BackgroundKnowledge of HBV genotype is very important for clinical treatment. Studies have suggested possible pathogenic and therapeutic differences among HBV genotypes. The aim of this study was to determine HBV subtypes and genotypes in HBV-infected patients in our region (southeast Brazil) and to correlate results with clinical and histopathological data.MethodsOne hundred and thirty-nine HBsAg-positive patients were included in the study. All patients were anti-HCV and anti-HIV negative (64% male; mean age 42 ± 14.5 years; range 7-80 years; 84% Caucasian) and were followed up at the University Hospital. A method for genotyping and subtyping HBV by partial HBsAg gene sequencing with primers common to all known genotypes was used. The viral load was measured by Amplicor Monitor assay (Roche).ResultsHBV genotype A was the most prevalent (55%), while genotypes C, D and F were found in 3%, 38% and 4% of HBV-infected patients, respectively. Among the patients infected by genotype A, 18.3% (14/76) were African descendents and, among the patients infected by genotype D, 11.3% (6/53) were also African descendents. In the four patients infected with genotype C, 2 were Asian descendents and 2 were Caucasians. All (7) genotype F infected patients were Caucasians. Seventy percent of our HBsAg-positive patients were HBeAg negative (62% genotypes A; 26.2% D; 7.1% C and 4.7%F). The viral load of HBV-DNA was about 5 times higher in HBeAg-positive than in HBeAg-negative patients. About 40% of these patients had alanine aminotransferase of up to 1.5 times the normal level. The mean stage of fibrosis in genotype A patients (2.8) was significantly higher than the mean stage of fibrosis in genotype D patients (2.0) (P = 0.0179).ConclusionThe genotypes encountered in our HBV-infected patients were apparently a consequence of the types of immigration that occurred in our region, where European and African descendents predominate. The HBeAg-negative status predominated, possibly due to the length of time of infection. The viral load in HBeAg-positive patients was higher than in HBeAg-negative individuals. The fibrosis grade in genotype A-infected patients was more advanced than genotype D-infected patients.
From 1992 to 1995 we studied 232 (69% male, 87% Caucasian) anti-human immunodeficiency virus (anti-HIV) positive Brazilian patients, through a questionnaire; HIV had been acquired sexually by 50%, from blood by 32%, sexually and/or from blood by 16.4% and by an unknown route by 1.7%. Intravenous drug use was reported by 29%; it was the most important risk factor for HIV transmission. The alanine aminotransferase quotient (qALT) was >1 for 40% of the patients, 93.6% had anti-hepatitis A virus antibody, 5.3% presented hepatitis B surface antigen, 44% were anti-hepatitis B core antigen positive and 53.8% were anti-hepatitis C virus (anti-HCV) positive. The anti-HCV test showed a significant association with qALT>1. Patients for whom the probable HIV transmission route was blood had a 10.8 times greater risk of being anti-HCV positive than patients infected by other routes. Among 30 patients submitted to liver biopsy, 18 presented chronic hepatitis. Key Words: Hepatitis C virus, human immunodeficiency virus, alanine aminotransferase quotient, anti-hepatitis A antibody, hepatitis B surface antigen, anti-hepatitis B core antigen (anti-HBc).
Occult hepatitis B virus (HBV) infections have been identified in patients with chronic hepatitis C virus (HCV) infection, although the clinical relevance of occult HBV infection remains controversial. We searched for serum HBV DNA in 106 HBsAg negative/anti-HBc positive patients with chronic HCV infection and in 150 blood donors HBsAg negative/anti-HBc positive/anti-HCV negative (control group) by nested-PCR. HCV genotyping was done in 98 patients and percutaneous needle liver biopsies were performed in 59 patients. Fifty-two patients were treated for HCV infection with interferon alone (n=4) or combined with ribavirin (n=48) during one year. At the end and 24 weeks after stopping therapy, they were tested for HCV-RNA to evaluate the sustained virological response (SVR). Among the 106 HCV-positive patients, 15 (14%) were HBV-DNA positive and among the 150 HCV-negative blood donors, 6 (4%) were HBV-DNA positive. Liver biopsy gave a diagnosis of liver cirrhosis in 2/10 (20%) of the HBV-DNA positive patients and in 6/49 (12%) of the HBV-DNA negative patients. The degree of liver fibrosis and portal inflammation was similar in HCV-infected patients HBV-DNA, irrespective of HBV-DNA status. SVR was obtained in 37.5% of the HBV-DNA positive patients and in 20.5% of the HBV-DNA negative patients; this difference was not significant. In conclusion, these data suggested that occult HBV infection, which occurs at a relatively high frequency among Brazilian HCV-infected patients, was not associated with more severe grades of inflammation, liver fibrosis or cirrhosis development and did not affect the SVR rates when the patients were treated with interferon or with interferon plus ribavirin.
The seroprevalence of anti-hepatitis E virus (HEV) antibodies was investigated by enzyme immunoassay in 205 volunteer blood donors, 214 women who attended a center for anonymous testing for human immunodeficiency virus (HIV) infection, and 170 hospital employees in Campinas, a city in southeastern Brazil. The prevalence of anti-HEV antibodies ranged from 2.6% (3 of 117) in health care professionals to 17.7% (38 of 214) in women who considered themselves at risk for HIV. The prevalence of anti-HEV antibodies in health care professionals was not significantly different from that in healthy blood donors (3.0%, 5 of 165) and blood donors with raised alanine aminotransferase levels (7.5%, 3 of 40). The prevalence of anti-HEV antibodies (13.2%, 7 of 53) in cleaning service workers at a University hospital was similar to that among women at risk for HIV infection. These results suggest that HEV is circulating in southeastern Brazil and that low socioeconomic status is an important risk factor for HEV infection in this region.Hepatitis E virus (HEV) is considered the main etiologic agent of enterically transmitted non-A, non-B hepatitis (ET-NANBH) and occurs in epidemics or sporadically. ET-NANBH, once thought to be a disease confined to developing countries, is now recognized to have a wider geographical distribution (12,33). Epidemics have been related to contaminated water supplies, as fecal-oral transmission is the major route of transmission (29). The symptoms of ET-NANBH are similar to those of hepatitis A, although it affects primarily young adult populations already immune to hepatitis A virus (HAV). HEV is well recognized as a cause of fulminant hepatic failure in areas where it is endemic (23), particularly in pregnant women who contract it in the third trimester (10). In developed countries, sporadic cases have been identified among travelers from areas where it is endemic and HEV has been implicated in some community-acquired cases of NANBH in the United States and other western countries (12).Until recently, the diagnosis of ET-NANBH was based on serology after the exclusion of other viral hepatitis. In 1990, the isolation of a partial cDNA clone from HEV (22) led to the identification of type-common immunodominant epitopes and the development of diagnostic serological assays for the detection of antibodies to recombinant HEV antigens (4).The prevalence of HEV infection among blood donors in developed countries ranges from 0.4 to 3.9% (4,14,15). An association between HEV and hepatitis C virus infections has been reported, suggesting similar or overlapping routes of transmission (21). In addition, a higher prevalence of antibodies to HEV has been reported among patients undergoing chronic hemodialysis (9), suggesting that this virus is also spread by the parenteral route. Homosexual men also have a high prevalence of HEV infection (15), and the possibility of sexual transmission cannot be neglected. Few studies have addressed the prevalence of HEV infection in Brazil because diagnostic tests for this illnes...
The wild and the variant alleles of the C936T and G634C vascular endothelial grow factor (VEGF) polymorphisms seem to be linked to higher angiogenic phenotype than the remaining alleles and may act on breast cancer (BC) origin. We investigated the influence of the VEGF C936T and G634C polymorphisms on the occurrence and clinicopathologic characteristics of sporadic breast cancer (SBC) in 235 patients and 235 controls. Peripheral blood samples of all individuals were analysed by the polymerase chain reaction for identification of genotypes and by enzyme-linked immunosorbent assay (ELISA) for quantification of serum VEGF levels. The variant 634CC genotype isolated (16.2% versus 10.7%, P = 0.01) and in combination with the wild 936CC genotype (10.6% versus 5.5%, P = 0.01) were more common in patients than in controls. The carriers of the respective genotypes were under a 2.20-fold and a 3.08-fold increased risks for the disease. Additionally, the frequency of the wild 936CC genotype was higher in patients with tumours of histological grade III compared to those with tumours of I+II histological grades (84.0% versus 64.7%, P = 0.004) and in patients with positive oestrogen receptor tumours compared to those with tumours lacking oestrogen receptor expression (84.7% versus 73.9%, P = 0.02). Similar serum values of VEGF were seen in patients and controls with the distinct genotypes of the VEGF. The data suggest that the VEGF wild 936CC and the variant 634CC genotypes constitute inherited determinants of SBC and SBC aggressiveness in Brazil, but are not significant predictors of circulating VEGF levels.
Occult hepatitis B infection is characterized by hepatitis B virus (HBV) DNA in the serum in the absence of hepatitis B surface antigen (HBsAg). We assessed occult HBV infection prevalence in two groups of immunocompromised patients (maintenance hemodialysis patients and HIV-positive patients) presenting HBsAgnegative and anti-HBc positive serological patterns, co-infected or not by HCV. Thirty-four hemodialysis anti-HIV negative patients, 159 HIV-positive patients and 150 blood donors who were anti-HBc positive (control group) were selected. HBV-DNA was detected by nested-PCR. Occult hepatitis B infection was not observed in the hemodialysis patients group but was found in 5% of the HIV-patients and in 4% of the blood donors. Immunosuppression in HIV positive patients was not a determining factor for occult HBV infection. In addition, no significant relationship between HBV-DNA and HCV co-infection in the HIV-positive patient group was found. A lack of significant associations was also observed between positivity for HBV-DNA and CD4 count, viral load and previous lamivudine treatment in these HIV-positive patients.
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