Serum hepatitis B surface antigen levels predict insignificant fibrosis and non-cirrhosis in hepatitis B e antigen positive patients with normal or mildly elevated alanine transaminase levels

Background/Aims: We aimed to evaluate the diagnostic value of serum hepatitis B surface antigen (HBsAg) levels for liver fibrosis in hepatitis B e antigen-positive [HBeAg (+)] chronic hepatitis B (CHB) patients with alanine transaminase (ALT)≤twice upper limit of normal (ULN). Methods: 505 patients who underwent liver biopsies and HBsAg quantitative detections were included. Liver histology was scored using METAVIR scoring system. The area under the receiver-operator curve (AUROC) was used to determine the diagnostic accuracy. Results: Of 505 CHB patients, 333 have HBeAg (+), and 172 have HBeAg (-). HBsAg levels and METAVIR fibrosis scores showed strong correlation (r=-0.50, p<0.001) in HBeAg (+) patients, but no correlation in HBeAg (-) patients (r=0.09, p=0.239). HBeAg (+) patients with insignificant fibrosis (F0-1) exhibited higher HBsAg levels than those with significant fibrosis (F2-4) (4.60 vs 4.12 log10IU/ml, p<0.001). HBeAg (+) patients with non-cirrhosis (F0-3) exhibited higher HBsAg levels than those with cirrhosis (F4) (4.48 vs 3.95 log10IU/ml, p<0.001). In this study, the AUROC of HBsAg was 0.86 for diagnosing insignificant fibrosis, and 0.91 for diagnosing non-cirrhosis in HBeAg (+) CHB patients. Conclusions: Serum HBsAg level can identify insignificant fibrosis and non-cirrhosis in HBeAg (+) CHB patients with ALT≤2 ULN, and thus avoid liver biopsy in this population.