Serum HBsAg quantification in clinical diagnosis and treatment of chronic hepatitis B

HBsAg is one of the oldest diagnostic markers for HBV infection, and serum HBsAg level is associated with HBV cccDNA level in hepatocytes, HBV replication capability, and host immune response. In recent years, with the development of serum HBsAg quantification and the concept of functional cure, HBsAg quantification has been taken more and more seriously in the clinical diagnosis and treatment of HBV infection. This article analyzes the role of serum HBsAg quantification from the aspects of natural disease course of chronic hepatitis B, prediction of response to antiviral therapy, and prediction of drug withdrawal.