Serum hepatitis B surface antigen quantification as a useful assessment for significant fibrosis in hepatitis B e antigen-positive hepatitis B virus carriers

Background and AimsThe role of serum quantitative hepatitis B surface antigen (qHBsAg) in identifying hepatitis B virus (HBV) carriers with significant fibrosis is unknown. This study aims to evaluate the diagnostic value of qHBsAg for hepatic fibrosis in hepatitis B e antigen (HBeAg)-positive HBV carriers. MethodsConsecutive biopsy-proven HBeAg-positive HBV carriers were prospectively recruited in our center from 2009 to 2011 and were randomly divided into training and validation set. Area under receiver-operator curve (AUC) was used to determine the diagnostic accuracy of simple tests for significant fibrosis (Scheuer stage, F2). ResultsOverall, a total of 197 eligible patients (median age 31 years; 149 males) were enrolled. The median qHBsAg was 4.20 (log(10) IU/mL). Significant fibrosis was confirmed in 112 (56.9%) patients. By logistical regression analysis, qHBsAg and -glutamyl transpeptidase were identified as predictors for significant fibrosis in training set (n=124). Thus, qHBsAg index and -glutamyl transpeptidase to qHBsAg ratio (GqHBsR) were selected for the subsequent analysis. In the training set, an AUC of 0.762, 0.826, 0.749, and 0.771 was observed for qHBsAg index, GqHBsR, FIB-4, and aspartate aminotransferase to platelet ratio index, respectively (all P<0.05). GqHBsR yielded a higher AUC than aspartate aminotransferase to platelet ratio index and FIB-4 (both P<0.05). Using the optimal cut-off of 7.78, GqHBsR showed a sensitivity of 78.9% and a specificity of 73.6%. About 80% of liver biopsy could be avoided in the entire cohort. ConclusionsSerum qHBsAg-based simple tests, especially GqHBsR, can accurately and specifically identify significant fibrosis in treatment-naive HBeAg-positive HBV carriers.