Hepatitis B virus: molecular genotypes and HBeAg serological status among HBV-infected patients in the southeast of Brazil

<p>Abstract</p> <p>Background</p> <p>Knowledge 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.</p> <p>Methods</p> <p>One 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).</p> <p>Results</p> <p>HBV 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).</p> <p>Conclusion</p> <p>The 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.</p

Antibody response to heat-inactivated hepatitis B vaccine (CLB-3mg) in hemodialysis patients and occupational risk personnel: a one year follow-up

Immune response against hepatitis B vaccine (CLB 3mg) was evaluated in 59 hemodialysis patients and 20 occupational risk personnel. Seroconversion was induced in 52.5% and 70.0% respectively. Twelve months after the first dose, 37.5% of patients and 60.0% of occupational risk personnel had detectable anti-HBs level. Antibody level was expressed in sample ratio units (SRU). Considering only the responders, in the patients group 38.7% had a low anti-HBs response (2.1-9.9 SRU) 32.3% a medium response (10-99.9 SRU) and 29.0% a high response (>100 SRU) while in occupational risk personnel these values were 14.3%, 64.3% and 21.4% respectively. The authors suggest the use of HBV vaccines with more elevated HBsAg concentration or a reinforced immunization schedule to improve the anti-HBs response not only for patients but also for healthy persons

Seven Human Immunodeficiency Virus (HIV) Antigen-Antibody Combination Assays: Evaluation of HIV Seroconversion Sensitivity and Subtype Detection

In this study, we evaluated the performance of two prototype human immunodeficiency virus (HIV) antigen-antibody (Ag-Ab) combination assays, one from Abbott Laboratories (AxSYM HIV Ag-Ab) and the other from bioMerieux (VIDAS HIV Duo Ultra), versus five combination assays commercially available in Europe. The assays were Enzygnost HIV Integral, Genscreen Plus HIV Ag-Ab, Murex HIV Ag-Ab Combination, VIDAS HIV Duo, and Vironostika HIV Uniform II Ag-Ab. All assays were evaluated for the ability to detect p24 antigen from HIV-1 groups M and O, antibody-positive plasma samples from HIV-1 groups M and O, HIV-2, and 19 HIV seroconversion panels. Results indicate that although all combination assays can detect antibodies to HIV-1, group M, subtypes A to G, circulating recombinant form (CRF) A/E, and HIV-1 group O, their sensitivity varied considerably when tested using diluted HIV-1 group O and HIV-2 antibody-positive samples. Among combination assays, the AxSYM, Murex, and VIDAS HIV Duo Ultra assays exhibited the best antigen sensitivity (at ∼25 pg of HIV Ag/ml) for detection of HIV-1 group M, subtypes A to G and CRF A/E, and HIV-1 group O isolates. However, the VIDAS HIV Duo Ultra assay had a lower sensitivity for HIV-1 group M and subtype C, and was unable to detect subtype C antigen even at 125 pg of HIV Ag/ml. The HIV antigen sensitivity of the VIDAS HIV Duo and Genscreen Plus combination assays was ∼125 pg of HIV Ag/ml for detection of all HIV-1 group M isolates except HIV-1 group O while the sensitivity of Vironostika HIV Uniform II Ag-Ab and Enzygnost HIV Integral Ag-Ab assays for all the group M subtypes was >125 pg of HIV Ag/ml. Among the combination assays, the AxSYM assay had the best performance for detection of early seroconversion samples, followed by the Murex and VIDAS HIV Duo Ultra assays