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1.
J Hosp Infect ; 64(4): 352-7, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17046105

RESUMO

Chronic infection with hepatitis B virus (HBV) is a major global health problem. Transmission is mainly blood-borne, although the route of infection during horizontal transmission in childhood is unclear. Nosocomial outbreaks of HBV have been widely reported, but have mainly focused on blood-borne transmission. There is limited knowledge of the viral load levels in other body fluids. In the present study, chronic HBV carriers were tested for the presence of HBV DNA in serum, saliva, nasopharyngeal fluid, urine and tears by means of qualitative and quantitative polymerase chain reaction (PCR) methods. Twenty-five patients who were positive for HBV DNA with both PCRs were included. Low titres in real-time PCR corresponded with weak bands in the qualitative assay. HBV DNA was found in two urine samples, 10 saliva samples, five nasopharyngeal swabs and in tear fluid from four patients. One highly viraemic HBeAg-positive carrier with serum HBV DNA levels of 7 x 10(9) genome copies had high copy numbers detected in both saliva and nasopharyngeal fluid. These results demonstrate that highly viraemic HBV carriers may have high titres of HBV DNA in other body fluids. This has particular importance for infection control programmes and regulations, underlining the importance of aiming towards regular HBV DNA testing and thus infectivity assessment of chronic carriers in order to prevent transmission.


Assuntos
Secreções Corporais/virologia , Infecção Hospitalar/transmissão , Anticorpos Anti-Hepatite B/sangue , Antígenos E da Hepatite B/sangue , Vírus da Hepatite B/genética , Hepatite B Crônica/transmissão , Controle de Infecções , Adulto , Portador Sadio , Infecção Hospitalar/prevenção & controle , Infecção Hospitalar/virologia , Feminino , Vírus da Hepatite B/isolamento & purificação , Hepatite B Crônica/prevenção & controle , Hepatite B Crônica/virologia , Humanos , Masculino , Carga Viral
2.
J Viral Hepat ; 12(5): 473-80, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16108761

RESUMO

SUMMARY: To optimize treatment of chronic hepatitis C early identification of patients who will not achieve a sustained virological response (SVR) is desirable. We investigated hepatitis C virus (HCV) RNA kinetics at day 1 (in 15 patients; genotypes 1 and non-1, 9 and 6 respectively) at weeks 1, 4 and 12 (in 53 patients; genotypes 1 and non-1, 19 and 34, respectively) during treatment with pegylated interferon alpha-2a and ribavirin. Patients with SVR had a significantly more pronounced mean log10 decline from baseline in HCV RNA levels at weeks 1 and 4 compared with patients who failed to achieve SVR (1.99 vs 0.85 at week 1, P = 0.0003 and 2.89 vs 1.72 at week 4, P = 0.0159), whereas no difference was noted after day 1. For patients with a 2-log10 decrease in HCV RNA levels at day 7, the positive predictive value (PPV) for a SVR was 92%, whereas week 12 was the best time point for predicting a later nonresponse [negative predictive value (NPV) 92%] in patients failing to achieve a 2-log10 drop. For patients with genotype non-1 and a 2-log10 decrease in HCV RNA levels the PPV for a SVR was 89% week 1, and 79% weeks 4 and 12. The corresponding NPV for patients with genotype non-1 were 43, 40 and 100% respectively. During treatment with pegylated interferon alpha-2a plus ribavirin the HCV RNA decline at week 1 was an accurate predictor of SVR in patients who had achieved a 2-log10 drop in HCV RNA levels, whereas the lack of such decline week 12 was an accurate marker of a nonresponse.


Assuntos
Antivirais/uso terapêutico , Hepacivirus/efeitos dos fármacos , Hepatite C Crônica/tratamento farmacológico , Interferon-alfa/uso terapêutico , Ribavirina/uso terapêutico , Adulto , Quimioterapia Combinada , Feminino , Hepacivirus/genética , Hepatite C Crônica/virologia , Humanos , Interferon alfa-2 , Interferon-alfa/metabolismo , Masculino , Pessoa de Meia-Idade , Polietilenoglicóis/metabolismo , RNA Viral/sangue , RNA Viral/efeitos dos fármacos , Proteínas Recombinantes , Resultado do Tratamento , Viremia/tratamento farmacológico
3.
J Hepatol ; 33(6): 992-7, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11131464

RESUMO

BACKGROUND/AIMS: After acute self-limited hepatitis B virus (HBV) infection, serological loss of viral antigens and appearance of anti-HBs is generally believed to signify viral clearance. Latent and occult HBV infection appearing decades after self-limited hepatitis B has not been reported, nor has the evolutionary rate of HBV DNA over the same observation period. METHODS: DNA from serum and leukocytes from 16 patients with acute self-limited hepatitis B 30 years earlier was tested by polymerase chain reaction and positive samples were sequenced. Liver tissue from four patients was also tested. Additionally, another 10 HBV strains isolated from acute HBV cases in 1969-72 were compared to 11 strains isolated from acute cases in 1998-99 in the same community. RESULTS: HBV DNA was detected in liver from two patients, but not in serum or leukocytes. The HBV strains detected in liver showed complete homology, in the sequences analyzed, to the strains originally infecting these patients. Ten strains from 1998-99 were identical in pre-S and core promoter/precore regions to strains from the same community isolated 30 years earlier. CONCLUSIONS: HBV can persist as an occult infection three decades after acute, apparently self-limited hepatitis B, and both the mutation and evolutionary rates of HBV DNA are low.


Assuntos
Vírus da Hepatite B/genética , Vírus da Hepatite B/isolamento & purificação , Hepatite B/virologia , Doença Aguda , Adolescente , Adulto , Criança , DNA Viral/genética , DNA Viral/metabolismo , Feminino , Genótipo , Hepatite B/genética , Humanos , Fígado/metabolismo , Masculino , Regiões Promotoras Genéticas/genética , Homologia de Sequência do Ácido Nucleico , Fatores de Tempo
4.
Eur J Clin Microbiol Infect Dis ; 19(1): 21-6, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10706175

RESUMO

The objective of this study was to investigate the epidemiology, etiology, and long-term outcome of an extended outbreak of acute hepatitis that occurred in an area of Sweden between 1969 and 1972. The outbreak was analyzed retrospectively by retesting stored frozen serum samples for the presence of hepatitis A, B and C markers. The results were compared with the diagnoses that had been determined during the outbreak. Of 180 patients, 29 (16%) had acute hepatitis A, 126 (70%) had acute hepatitis B, and eight (4.4%) had acute hepatitis C. The Australia antigen test used during the outbreak had failed to identify 21 patients with acute hepatitis B virus infection. Genotyping of the hepatitis B virus strains showed that genotype D was the most prevalent, irrespective of the transmission route. An attempt was made to follow up patients with unresolved hepatitis B virus infection, 25-27 years after the acute infection. None of the 100 patients with acute hepatitis B infection who were traced had become chronic carriers. In ten patients with hepatitis C virus infection, the follow-up showed considerable variation in the outcome, ranging from spontaneous resolution to death through liver cirrhosis. Intravenous drug users had a high prevalence of hepatitis C virus infection, with 52% testing positive for hepatitis C antibodies.


Assuntos
Surtos de Doenças , Hepatite B , Hepatite C , Doença Aguda , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Portador Sadio/epidemiologia , Criança , Feminino , Seguimentos , Hepatite A/epidemiologia , Hepatite A/transmissão , Hepatite A/virologia , Hepatite B/epidemiologia , Hepatite B/transmissão , Hepatite B/virologia , Vírus da Hepatite B/classificação , Vírus da Hepatite B/genética , Hepatite C/epidemiologia , Hepatite C/transmissão , Hepatite C/virologia , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Suécia/epidemiologia , Fatores de Tempo
5.
J Med Virol ; 60(2): 107-12, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10596007

RESUMO

Hepatitis B virus (HBV) strains from anti-HBe positive patients often show specific mutations in the precore gene, the core promoter region, or both. The dynamics of seroconversion in relation to the appearance of these mutations has not been studied and compared between defined HBV genotypes. Samples from patients followed during seroconversion from HBeAg to anti-HBe were amplified by polymerase chain reaction (PCR), sequenced and genotyped. Among 16 sets of samples, 6 belonged to genotype A, 6 to genotype D, 2 to genotype B, 1 to genotype C, and 1 to genotype E. Whereas strains from genotypes B, C and E showed changes in the core promoter, precore codon 28 or both, genotype A and D strains displayed a different pattern. In 4 of 6 anti-HBe positive samples from genotype A, the precore had a wild-type sequence while the core promoter sequence showed a specific TGA mutation. In another genotype A strain a precore stop mutation was preceded by a mutation in codon 15, thus conserving base-pairing at the pregenomic RNA level in this region. In contrast, all genotype D strains showed wild-type sequences in both the core promoter and precore codon 28 in pre- and post-seroconversion samples. Thus, in 8 patients with a mean follow-up time of 17 months, wild-type sequences in both the core promoter and precore codon 28 were found after seroconversion to anti-HBe. This study also confirmed, for genotype D, that HBeAg seroconversion often occurs earlier than genomic conversion.


Assuntos
Antígenos E da Hepatite B/imunologia , Vírus da Hepatite B/genética , Hepatite B/virologia , Regiões Promotoras Genéticas , Proteínas do Core Viral , Adolescente , Adulto , Anticorpos Antivirais/sangue , Biomarcadores/sangue , Criança , Códon/genética , Análise Mutacional de DNA , Feminino , Variação Genética , Genótipo , Hepatite B/imunologia , Antígenos da Hepatite B , Vírus da Hepatite B/classificação , Humanos , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase
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