HBsAg Level as Predictor of Liver Fibrosis in HBeAg Positive Patients With Chronic Hepatitis B Virus Infection

Background and aims: Preliminary data suggests lower serum hepatitis B surface antigen level is associated with more severe liver fibrosis in HBeAg positive patients. We evaluated the association of HBsAg level with biochemical, virological, and histological features in asymptomatic patients with chronic HBV infection. Methods: HBsAg levels were measured at baseline in 481 asymptomatic, treatment naive patients with chronic HBV infection. Subjects were followed-up prospectively (median, 12; range, 8-36 months). Phases of HBV infection were defined after regular monitoring of HBV-DNA and transaminases. Liver histology was scored using the METAVIR system. Results: HBeAg positive (n, 126) patients were significantly younger than HBeAg negative (n, 355), median age 26 vs 30 years; P < 0.01. HBV genotype could be determined in 350 patients, 240 (68.57%) had genotype D and 100 (28.57%) had genotype A. HBsAg level had modest correlation with serum HBV DNA(r = 0.6 vs 0.4 in eAg positive & negative respectively). HBeAg + ve patients with fibrosis score >= F2 showed significantly lower median serum HBsAg levels and serum HBV DNA levels compared with patients with F0-F1 score (median, range; 4.51, 2.99-6.10 vs 5.06, 4.13-5.89, P < 0.01) and (8.39, 3.85-10.60, P < 0.01) respectively. Significant inverse correlation of HBsAg level was found with liver fibrosis in eAg positive group (r = -0.76; P < 0.001). HBsAg level cut off value 4.7 log10 IU/ml predicted moderate to advance fibrosis (F >= 2) with 92% sensitivity, 85% specificity & 91% negative predictive value. Conclusion: Lower HBsAg level might reflect the status of advanced liver fibrosis in HBeAg positive chronic hepatitis B subjects.