GPT and hepatitis A virus infection: Table 1 summarizes the definitions of HBV-R based on the different guidelines. Additionally, the AASLD also provides explicit concepts for HBV-associated hepatitis, namely, acute serum alanine aminotransferase (ALT) levels ≥3-fold higher than that at baseline and an absolute value >100 U/L (26). Interestingly, it has been reported that monitoring ALT levels can lead to the earlier detection of HBV-R because ALT levels increase 2–3 weeks before a rise in HBV DNA levels is detected (31).