Hepatitis B and C virus variants in long-term immunosuppressed renal transplant patients in Latvia.
ABSTRACT The incidence of genome variants of hepatitis B and hepatitis C viruses among 38 long-term (2-15 years) immunosuppressed patients after renal transplantation and 10 patients undergoing dialysis was investigated. Twelve patients had only HBV infection, 9 had only HCV infection and 14 were co-infected. Regions corresponding to the HBV X/EnII/BCP, preC/C, preS/S and to the HCV core were sequenced for molecular characterization of the HBV and HCV genomes. Fifty-seven percent of HBV DNA isolates belonged to genotype D and 42% to genotype A, whereas 77% of HCV RNA isolates belonged to genotype 1b and only 17% to genotype 3a. One sample (6%) was of genotype 2c. Detailed analysis of the above-mentioned HBV genome regions revealed the presence of nucleotide point mutations, which, in some cases, resulted in amino acid substitutions. The clinical significance of such mutations is discussed.
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ABSTRACT: Hepatitis B virus (HBV) infection has a high prevalence among hemodialysis and renal transplant patients. Data regarding genotype distribution in these populations are scarce and are still under investigation. The aim of this study was to evaluate the distribution of HBV genotypes in end-stage renal disease (ESRD)-patients and renal transplant patients and to compare with the distribution observed in immunocompetent patients from the same geographic region. From a population of 213 patients evaluated initially, 120 patients with detectable HBV-DNA were included in the study and submitted to genotype determination by amplification of S gene by nested PCR followed by sequencing method. Among 41 hemodialysis patients the most frequent genotype was D (83%), followed by genotype A (10%), C (5%), and F (2%). Genotype D was also the most prevalent (73%) among 33 renal transplant patients, followed by genotype A (18%), F (6%), and B (3%). This distribution was similar in these two groups of patients and for the comparative analysis they were considered in the kidney disease group. Compared to immunocompetents, patients with kidney disease (ESRD and renal transplant patients) showed a distinct distribution, with a higher prevalence of genotype D (78% vs. 17%, P < 0.001) whereas genotype A was the most prevalent among immunocompetent patients (70% vs. 14%, P < 0.001). In conclusion, the higher frequency of genotype A in immunocompetent patients and of genotype D in patients with renal disease suggest a higher capacity of environmental transmission or a better adaptability of this genotype in patients with a different pattern of immunologic response.Journal of Medical Virology 10/2012; 84(10):1548-52. · 2.22 Impact Factor
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ABSTRACT: Hepatitis B virus (HBV) infection has a major effect on health care systems, with about one-third of the world's population currently infected with the virus. There is an effective vaccine against HBV, which contains a recombinant "surface antigen" produced in an expression vector. Vaccination has proved to be successful in Hungary: the number of acute HBV cases has decreased in the past 10 years. Although an increasing number of publications report on "vaccine-escape" HBV variants which can infect HBV-vaccinated individuals, such mutant HBV strains have not yet been detected in Hungary. We therefore surveyed two risk groups for vaccine-escape or immunoglobulin-escape HBV mutations in Hungary: 28 actively and/or passively HBV-immunized children of HBV carrier mothers who proved to be HBsAg and/or anti-HBc positive and 40 symptomless HBV carrier pregnant women (presumably carrying genotype B or C). We focused on the coding sequences of the "a" immundominant region of the surface protein. We could not detect the G145R amino acid substitution associated with vaccine escape mutant virus. However, we could map other mutations potentially affecting the immunodominant "a" region of the HBV surface protein.Archives of Virology 10/2008; 153(10):1885-92. · 2.28 Impact Factor
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ABSTRACT: Knowledge of the genotypic distribution of hepatitis B virus (HBV) facilitates epidemiologic tracking and surveillance of HBV infection as well as prediction of its disease burden. In the United States, HBV genotyping studies have been conducted for chronic but not acute hepatitis B. Serum samples were collected from patients with acute hepatitis B cases reported from the 6 counties that participated in the Sentinel Counties Study of Acute Viral Hepatitis from 1999 through 2005. Polymerase chain reaction followed by nucleotide sequencing of a 435-base pair segment of the HBV S gene was performed, and the sequences were phylogenetically analyzed. Of 614 patients identified with available serum samples, 75% were infected with genotype A HBV and 18% were infected with genotype D HBV. Thirty-two percent of genotype A sequences constituted a single subgenotype A2 cluster. The odds of infection with genotype A (vs with genotype D) were 5 times greater among black individuals than among Hispanic individuals (odds ratio [OR], 5; 95% confidence interval [CI], 2.3-10.7). The odds of infection with genotype A were 49, 8, and 4 times greater among patients from Jefferson County (Alabama), Pinellas County (Florida), and San Francisco (California), respectively, than among those living in Denver County (Colorado). Genotype A was less common among recent injection drug users than it was among non-injection drug users (OR, 0.2; 95% CI, 0.1-0.4). HBV genotype distribution was significantly associated with ethnicity, place of residence, and risk behavior.Clinical Infectious Diseases 08/2011; 53(8):751-6. · 9.42 Impact Factor