GPT and chronic hepatitis B virus infection: The initial phase of natural course of chronic hepatitis B (CHB) is the immune-tolerance phase (HBeAg-positive chronic infection), in which serum alanine aminotransferase (ALT) remains within normal range though the serum HBV DNA level is over 20,000 IU/ml (nearly the upper limit of the measurement in practice) due to the active HBV replication rate; however, liver damage is minimal (6).