RESUMO

Twenty-two vertically human immunodeficiency virus type 1 (HIV-1) infected Brazilian children were studied for antiretroviral drug resistance. They were separated into 2 groups according to the administration of antiretroviral therapy into those who presented disease symptoms or without symptoms and no therapy. Viral genome sequencing reactions were loaded on an automated DNA sampler (TruGene, Visible Genetics) and compared to a database of wild type HIV-1. In the former group 8 of 12 children presented isolates with mutations conferring resistance to protease inhibitors (PIs), 7 presented isolates resistant to nucleoside reverse transcriptase inhibitors (NRTIs) and 2 presented isolates resistant to non-nucleoside reverse transcriptase inhibitors (NNRTIs). Ten children were included in the antiretroviral na ve group. Eight were susceptible to NRTIs and all of them were susceptible to PIs; one presented the V108I mutation, which confers low-level resistance to NNRTIs. The data report HIV mutant isolates both in treated and untreated infants. However, the frequency and the level of drug resistance were more frequent in the group receiving antiretroviral therapy, corroborating the concept of selective pressure acting on the emergence of resistant viral strains. The children who presented alterations at polymorphism sites should be monitored for the development of additional mutations occurring at relevant resistance codons.

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RESUMO

Twenty-two vertically human immunodeficiency virus type 1 (HIV-1) infected Brazilian children were studied for antiretroviral drug resistance. They were separated into 2 groups according to the administration of antiretroviral therapy into those who presented disease symptoms or without symptoms and no therapy. Viral genome sequencing reactions were loaded on an automated DNA sampler (TruGene, Visible Genetics) and compared to a database of wild type HIV-1. In the former group 8 of 12 children presented isolates with mutations conferring resistance to protease inhibitors (PIs), 7 presented isolates resistant to nucleoside reverse transcriptase inhibitors (NRTIs) and 2 presented isolates resistant to non-nucleoside reverse transcriptase inhibitors (NNRTIs). Ten children were included in the antiretroviral naﶥ group. Eight were susceptible to NRTIs and all of them were susceptible to PIs; one presented the V108I mutation, which confers low-level resistance to NNRTIs. The data report HIV mutant isolates both in treated and untreated infants. However, the frequency and the level of drug resistance were more frequent in the group receiving antiretroviral therapy, corroborating the concept of selective pressure acting on the emergence of resistant viral strains. The children who presented alterations at polymorphism sites should be monitored for the development of additional mutations occurring at relevant resistance codons

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O diagnostico laboratorial da infeccao pelo virus da imunodeficiencia humana tipo 1 pode ser feito mediante a aplicacao de testes sorologicos de terceira geracao. Reatividade inespecificas podem, entretanto, ser observadas em diferentess grupos populacionais, para a deteccao de anticorpos contra HIV por metodos imunoenzimaticos, conforme observado na analise de amostras sorologicas de gestantes (3,9 porcento), hepatopatas (3,0 porcento) e populacao pediatrica (1,03 porcento). Os valores de inespecificidade reforcam o conceito de que a deteccao de anticorpos contra HIV deve ser feita pela analise e interpretacao de, ao menos, dois testes de diferentes procedencias, em uma primeira coleta. Metodos de triagem de quarta geracao, que permitem a deteccao simultanea de anticorpos e antigeno p24 do HIV, apresentam sensibilidade comparavel a das metodologias tradicionais, sendo de particular valor no diagnostico precoce da infeccao. Diferentes amostras de sangue de tres pacientes, coletadas em periodos distintos, foram analisadas comparativamente por testes imunoenzimaticos de terceira geracao (Cobas, Axsym e Ortho) e quarta geracao (ELFA HIV DUO). Os resultados demonstram a possibilidade de antecipar a deteccao dos marcadores da infeccao viral em periodos que podem variar de quatro a 12 dias, quando comparados a metodos de terceira geracao, que detectam apenas anticorpos

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Hepatic viscerotomy of paraffin-preserved old specimens, collected in the period from 1934 to 1967, were analyzed by immunohistochemical assays to detect hepatitis B, hepatitis D, dengue and yellow fever virus antigens. The material belongs to the Yellow Fever Collection, Department of Pathology, Instituto Oswaldo Cruz, Rio de Janeiro, Brazil and the cases were diagnosed at that time according to clinical aspects and histopathological findings reporting viral hepatitis, yellow fever, focal necrosis and hepatic atrophy. From the 79 specimens, 69 were collected at the Labrea Region and the other 10 in difFerent other localities in the Amazon Region. The five micra thick histological slices were analyzed for the presence of hepatitis B surface antigen (HBsAg) and hepatitis B core antigen (HBcAg) by immunoperoxidase technique. An immunofluorescence assay was applied to the detection of hepatitis D, yellow fever and dengue virus antigens. Nine (11.4%) histological samples were HBsAg reactive and 5 (6.3%) were HBcAg reactive. The oldest reactive sample was from 1934. Viral antigens related to the other pathologies were not detected in this study. Our results confirm that the methodology described may be used to elucidate the aetiology of hepatitis diseases even after a long time of conservation of the specimens.

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RESUMO

Hepatic viscerotomy of paraffin-preserved old specimens, collected in the period from 1934 to 1967, were analyzed by immunohistochemical assays to detect hepatitis B, hepatitis D, dengue and yellow fever virus antigens. The material belongs to the Yellow Fever Collection, Department of Pathology, Instituto Oswaldo Cruz, Rio de Janeiro, Brazil and the cases were diagnosed at that time according to clinical aspects and histopathological findings reporting viral hepatitis, yellow fever, focal necrosis and hepatic atrophy. From the 79 specimens, 69 were collected at the Labrea Region and the other 10 in different other localities in the Amazon Region. The five micra thick histological slices were analyzed for the presence of hepatitis B surface antigen (HBsAg) and hepatitis B core antigen (HBcAg) by immunoperoxidase technique. An immunofluorescence assay was applied to the detection of hepatitis D, yellow fever and dengue virus antigens. Nine (11.4 percent) histological samples were HBsAg reactive and 5 (6.3 percent) were HBcAg reactive. The oldest reactive sample was from 1934. Viral antigens related to the other pathologies were not detected in this study. Our results confirm that the methodology described may be used to elucidate the aetiology of hepatitis diseases even after a long time of conservation of the specimens

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Two hundred and fifty two blood donors HBsAg positive (mean age = 32.6, 91, 7% male) were searched into a transversal study to determine their clinical, laboratorial and histological characteristics. It was also compared the positiviness and negativiness of the serologic markers HBeAg, anti-Hbe and IgM anti-HBc with the values of serum aminotransferases. Hepatomegaly and splenomegaly were detected in 9.9% (25/252) and in 2.4% (6/252) respectively. In 17.5% (44/251) and 28.3% (71/251) the AST and ALT were respectively, over 50 UI/I. The positive frequencies of the various serologic markers of hepatitis B virus in 120 patients were: anti-HBc total in 89.5% (102/114), HBeAg in 25.7% (28/109) anti-Hbe in 67.3% (66/98), IgM anti-HBc in 40.8% (49/120); anti-Delta in 0.0% (0.66). Thirty one patients were submitted to liver biopsy, due do clinical alteration and/or of the aminotransferases. The hystological findings were: normal liver in 16.1% (5/31), non specific hystological alterations in 22.6% (7/31), persistent chronic hepatitis in 22.6% (7/31), active chronic hepatitis in 6.5% (2/31), cirrhosis in 12.9% (4/31), alcoholic hepatitis in 3.2% (1/31), lobular chronic hepatitis in 3.2% (1/31) and alterations exclusively due to schistosomiasis in 12.9% (4/31). Schistosomiasis elements (granuloma and/or Symmers fibrosis) were also notived in 7 patients. The comparative analysis of positiveness and negativeness of the serologic markers with the aminotransferases ("t" test of Student) showed significative difference of the averages (p < 0.05) only in relation to the simultaneous positeveness and negativeness of the HBeAg and IgM anti-HBc (average of AST = 56.11 and ALT = 78.00 when HBeAg and IgM anti-HBc were positive; average of AST = 24.25 and ALT = 27.00 when HBeAg and IgM anti-HBc were negative). According to this study the conclusion are: 1) The presence of two markers (HBeAg and IgM anti-HBc) and not only one determinant of viral replication in asymptomatic HBsAg carriers can strongly indicate a significant biochemical activity suggestive of hepatocellular lesion. 2) The presence of HBeAg in 25.7% (28/109) clearly shows the high rate of carriers with a potential of infectivity. 3) The results of hepatic histology shows that the majority of our patients had either normal liver or mild histological alterations. It is important to notice that only the cases with elevated aminotransferases were submitted to liver biopsies. The alterations caused by schistosomiasis shows, as is well known, the high prevalence of the parasitism in our surroundings. 4) The clinical aspects of the patients studied did not show significant alterations. Risk factors to get the infection were low. The hematologic and biochemical parameters (except aminotransferases) were either normal or just slightly abnormal. It was not detected a statistically significant difference. 5) The co-infections by delta virus was null.

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Serum samples were non-randomly obtained from apparently healthy inhabitants of 5 villages in the Amazonas State, Brazil. Sera were tested by enzyme immunoassay for the presence of hepatitis B surface antigen (HBsAg) and, if this was found, for antibody to hepatitis delta virus (HDV). Of 574 people tested, 96 (16.7%) were reactive for HBsAg and 33 of these (34.4%) for anti-HDV. The results were analysed according to sex, age and history of jaundice and showed a high prevalence of hepatitis B virus (HBV) and HDV infections in these asymptomatic persons, mainly in young people. The rates of prevalence observed in Amazonas for both HBV and HDV are perhaps among the highest in the world, demonstrating that these viruses are endemic in this region of Brazil.

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