Background: The clinical relevance of the G1896A precore mutation in chronic hepatitis B is still poorly understood.
Objectives: To assess the frequency of G1896A precore mutation in Brazilian patients with chronic hepatitis B, as well as its relation to the viral genotype, serum HBV-DNA levels and liver damage.
Study design: Fifty chronic hepatitis B patients (29 HBeAg-negative and 21 HBeAg-positive) were studied. HBV-DNA was quantified by the Amplicor HBV Monitor test and precore region and S gene were amplified and submitted to automatic sequencing. The histological activity index (HAI), degrees of hepatic fibrosis and distribution of core antigen (HBcAg) in hepatocytes were determined.
Results: Precore mutation occurred in 1/21 (4.8%) HBeAg-positive patients and in 17/29 (58.6%) HBeAg-negative (p < 0.0001). Genotype D was identified in 56.5%, genotype A in 41.3%, and genotype F in 2.2%. The frequency of genotypes D and A, as well as serum levels of ALT and HBV-DNA were similar in patients infected with wild type and with precore mutant. Patients infected with precore mutant presented a higher frequency of moderate/severe HAI (p: 0.03) and moderate/severe fibrosis and cirrhosis (p: 0.03) than those infected with wild type. There was no association between G1896A mutation and cytoplasmic expression of HBcAg.
Conclusions: Precore mutation was frequent among Brazilian subjects with chronic hepatitis B and its presence was associated with greater severity of liver disease.