Unexpected distribution of hepatitis B genotypes in patients with kidney disease: comparison with immunocompetent subjects.

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.

Low HBV-DNA levels in end-stage renal disease patients with HBeAg-negative chronic hepatitis B.

In end-stage renal disease patients treated by hemodialysis with HBeAg-negative chronic hepatitis B virus (HBV) infection, the evaluation of the presence of viral replication is essential in the assessment for renal transplantation. Data on HBV viral load, prevalence of precore mutations, as well as the influence of HCV coinfection on HBV-DNA levels in this group of patients is scarce. The aim of this study was to determine the HBV viral load in HBsAg-positive/HBeAg-negative hemodialysis patients; to compare HBV-DNA levels between isolated HBV infection carriers and HBV-HCV coinfected patients, and to evaluate the prevalence of precore mutations in these patients. Fifty hemodialysis patients with chronic HBeAg-negative HBV infection were studied. Viral load was determined by PCR (Amplicor HBV Monitor-Roche). The detection of precore mutations was made by sequencing. Of a total of 50 patients, 76% were male, with a mean age of 44 +/- 11 years. Anti-HCV was positive in 56% of patients. HBV-DNA was undetectable in 58% of patients; 24% had HBV-DNA <10,000 copies/ml, 12% between 10,000-100,000 copies/ml, and only 6% had HBV-DNA >100,000 copies/ml. There was no difference in the viral load of patients infected only by HBV and HBV-HCV co-infected patients (P = 0.96). Precore mutations were detected in only 8% of cases. In conclusion, hemodialysis patients with HBeAg-negative HBV infection had a low viral load. Precore mutations were infrequent and the presence of anti-HCV has not influenced the levels of HBV-DNA.