Estudo molecular da infecção pelo vírus da hepatite B em pacientes coinfectados pelo HIV, virgens de tratamento, em Goiânia-Goiás

• Autor(a) principal: Oliveira, Marina Pedroso de
• Data de Publicação: 2013
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Repositório Institucional da UFG
• Texto Completo: http://repositorio.bc.ufg.br/tede/handle/tede/3470
• topic: Hepatite B; Coinfecção HBV-HIV; Infecção oculta; Genótipos; Mutações; Hepatitis B; HBV-HIV co-infection; Occult infection; Mutations; Gnotypes; SAUDE COLETIVA::SAUDE PUBLICA

It is estimated that about 10% of individuals infected with human immunodeficiency virus (HIV) throughout the world have chronic infection with hepatitis B virus (HBV). The HIV-HBV co-infection increases the risk for developing cirrhosis and hepatocellular carcinoma. Also, co-infected individuals have atypical serological profiles more often than monoinfected patients, many of whom may have occult hepatitis B (presence of HBV-DNA in serum and/or liver in the absence of HBsAg) in addition to mutations in the viral genome that may have implications for the prognosis and therapeutics of hepatitis B. This study aimed to estimate the prevalence of occult HBV infection in HIV-infected treatment-naive patients, in Goiânia, Goiás, to determine the viral load of HBV-DNA positive samples, to identify circulating genotypes/subgenotypes and to investigate the occurrence of mutations in P and S regions of the HBV genome. This is a cross-sectional study conducted in HIV-infected treatment-naive patients attended at a reference hospital for infectious diseases in the Goiania city. After serological screening of the population (n = 505), two groups of patients were selected for this study: (i) 99 anti-HBc positive/HBsAg negative and (ii) 29 HBsAg reactive individuals. HBV-DNA was detected by semi-nested PCR and quantified by real time PCR. The amplicons were genotyped by RFLP and nucleotide sequencing. The identification of mutations in the viral genome was made by deduction of the amino acid sequences from the nucleotides sequences. The search for occult HBV infection performed in 99 anti-HBc positive/HBsAg negative samples (Group 1) showed a prevalence of 16.2% (16/99, 95% CI: 9.8-25.2). Of 29 HBsAg positive patients (Group 2), HBV-DNA was detected in 69% (20/29). As expected, DNA levels in the HBsAg reactive patients were significantly higher than those found in patients with occult infection (mean 2.89 x 108 copies/ml vs 6.59 x 102 copies/ml, p < 0.01). The genotypes (subgenotypes) A (A1 and A2), D (D2 and D3) and F (F2) were identified, being A/A1 the most frequently found. Mutations in the S region of HBV were found in both groups of patients, whereas mutations in the P region were observed only in patients HBsAg positive. These results revealed a high prevalence of occult HBV infection, the predominance of genotype A (A1), and the presence of mutations in the viral genome of HBV-HIV co-infected treatment-naive patients in Goiânia, Goiás.