Clinical and virological characterization of chronic hepatitis B in the state of Minas Gerais, Brazil

Abstract

Introduction/Aim: Although chronic HBV infection is a global health problem, there are geographical differences in endemicity and virological characteristics of infection even in the same country. The increasing prevalence of HBeAg-negative hepatitis has been observed in some areas in Brazil. The aim of this study was to investigate the clinical and virological characteristics of patients with chronic hepatitis B in Minas Gerais, the second Brazilian state in population. Methods: In a retrospective cross-sectional study, 235 patients with confirmed chronic hepatitis B monoinfection in replicative phase (HBsAg positive >6 months, HBVDNA > 2000 UI/mL) admitted at the University Hepatitis Reference Center between 1998 and 2011 were included. Demographic, clinical and virological characteristics were analyzed. This study was approved by the Ethics Committee of UFMG. Results: Overall, 169 (71.9%) patients were male, with mean age of 44.1± 12.4 years. The known ways of transmission were vertical in 32 (13.6%), sexual in 27 (11.5%) and blood transfusion in 26 (11.1%). In 143 (60.9%), the transmission mode could not be confirmed. The HBV genotype A was identified in 88/96 (91.7%), followed by genotypes D(3.1%), F (3.1%), B (1.0%) and G (1.0%). 156 (66.4%) and 79 (33.6%) patients were HBeAg negative and positive, respectively, with median age of 46.0± 11.2 and 42.0± 14.6 years (p=0.12), male/female 102/54 and 67/12 (p=0.002), respectively. ALT levels were lower in HBeAg-negative compared with HBeAg positive patients (median of 46.0+/- 73.0 IU/mL vs. 80.0± 104.2 IU/mL, p<0.001). The HBV viremia was lower in HBeAg negative compared with HBeAg positive patients (4.51 log10 IU/mL vs. 6.85 log10 IU/mL, p<0.001). The confirmed diagnostics of cirrhosis and HCC in HBeAg-negative and positive patients were: 60/156 (38.5%) vs. 46/79 (58.2%) (p=0.004) and 11/156 (7.1%) and 8/79 (6.7%) (p=0.41), respectively. The risk of cirrhosis was independently associated with age > 50 years (OR=5.45, 95% CI = 2.88 to 10.36, p<0.001) and male gender (OR=3.21, 95% CI = 1.64 to 6.32, p<0.001), but not with HBeAg status (p=0.21) or high HBV viremia (p=0.92). 18/19 (94.7%) patients with HCC were cirrhotic. Age >50 years was associated with development of HCC (OR=3.90, CI 95% = 1.35 to 11.54, p=0.008) independently of HBeAg status or HBV load. Conclusions: High prevalence of chronic hepatitis B HBeAg-negative and genotype A can be observed in Minas Gerais (Brazil). HBeAg-negative patients had lower ALT and HBV viral load as compared with HBeAg-positive patients. Cirrhotic patients over 50 years had higher risk of development of HCC regardless the status of HBeAg.