Prevalence, risk factors and genotypes of hepatitis B infection among HIV-infected patients in the State of MS, Central Brazil.

Objectives: A cross-sectional study on prevalence of HBV and HDV infection, risk factors and genotype distribution of HBV infection was conducted among 848 HIV-infected patients in Mato Grosso do Sul, Central Brazil.

Methods: Serum samples of 848 participants were tested for hepatitis B surface antigen (HBsAg), hepatitis B core antibody (anti-HBc) and hepatitis surface antibody (anti-HBs). HBsAg positive samples were tested for anti-HBc IgM, HBeAg, anti-HBe, anti-HCV, and total anti-HDV. HBsAg and anti-HBc positive were subjected to DNA extraction. Viral DNA was amplified by semi-nested PCR for the regions pre-S/S and then purified and genotyped/subgenotyped by direct sequencing. Student's t-test, chi-square test and Fisher's exact test were used to compare variables and to evaluate association between HBV positivity (defined as anti-HBc and/or HBsAg positivity) and risk factors.

Results: Among the 848 HIV infected patients investigated 222 had serological markers of HBV infection. The prevalence rate of HIV-HBV coinfection was 2.5% (21/848; 95% CI: 1.4-3.5%); 484 (57.1%) patients were susceptible for HBV infection. There were no cases of anti-HDV positive and only one (0.1%) anti-HCV-positive case among the HIV-HBV coinfected patients. Male gender, increasing age, family history of hepatitis, use of illicit drug, and homosexual activity were independent factors associated with HBV exposure. The phylogenetic analysis based on the S gene region revealed the presence of genotypes D (76.9%), F (15.4%) and A (7.7%) in the study sample.

Conclusion: This study demonstrates the low prevalence of HIV-HBV infection and also highlights the need for early vaccination against HBV as well as testing for HBV, HCV and HDV in all HIV-infected individuals.