High Hepatitis B Surface Antigen Levels Predict Insignificant Fibrosis in Hepatitis B e Antigen Positive Chronic Hepatitis B

Introduction: There is no data on the relationship between hepatitis B surface antigen (HBsAg) levels and liver fibrosis in hepatitis B e antigen (HBeAg)-positive patients with chronic hepatitis B (CHB). Methods: Serum HBsAg and HBV DNA levels in HBeAg-positive CHB patients with liver biopsies were analyzed. The upper limit of normal (ULN) of alanine aminotransferase (ALT) was 30 and 19 U/L for men and women respectively. Histologic assessment was based on Ishak fibrosis staging for fibrosis and Knodell histologic activity index (HAI) for necroinflammation. Results: 140 patients (65% male, median age 32.7 years) were recruited. 56 (40%) had ALT <= 2xULN. 72 (51.4%) and 42 (30%) had fibrosis score <= 1 and necroinflammation grading <= 4 respectively. Patients with fibrosis score <= 1, when compared to patients with fibrosis score >1, had significantly higher median HBsAg levels (50,320 and 7,820 IU/mL respectively, p<0.001). Among patients with ALT <= 2xULN, serum HBsAg levels achieved an area under receiver operating characteristic curve of 0.869 in predicting fibrosis score <= 1. HBsAg levels did not accurately predict necroinflammation score. HBsAg >= 25,000 IU/mL was independently associated with fibrosis score <= 1 (p = 0.025, odds ratio 9.042). Using this cut-off HBsAg level in patients with ALT <= 2xULN, positive and negative predictive values for predicting fibrosis score <= 1 were 92.7% and 60.0% respectively. HBV DNA levels had no association with liver histology. Conclusion: Among HBeAg-positive patients with ALT <= 2xULN, high serum HBsAg levels can accurately predict fibrosis score <= 1, and could potentially influence decisions concerning treatment commencement and reduce the need for liver biopsy.