Biochemical tests 1. Serum ALT and AST Serum ALT and AST levels generally reflect the degree of hepatocellular damage and are most commonly used. 2.Serum bilirubin Usually serum bilirubin level is related to the degree of hepatocyte necrosis, but it needs to be distinguished from bilirubin elevation caused by intrahepatic and extrahepatic biliary stasis. In patients with liver failure, serum bilirubin may increase progressively, rising ≥ 1 times the upper limit of normal (ULN) per day, and may be ≥ 10×ULN; bilirubin may also appear to be separated from ALT and AST. 3.Serum albumin reflects the synthesis function of the liver. Patients with chronic hepatitis B, cirrhosis and liver failure may have decreased serum albumin. 4.Prothrombin time (PT) and PTA PT is an important indicator reflecting the synthesis function of hepatic coagulation factors, and PTA is a common method of PT measurement, which is of great value in judging disease progression and prognosis. International normalized ratio (INR) is also used to express this index, and the increase of INR value is of the same significance as the decrease of PTA value. 5.Cholinesterase can reflect the synthetic function of the liver, and has a reference value for understanding the severity of the disease and monitoring the development of liver disease. 6.AFP (alpha-fetoprotein) AFP is significantly elevated mainly in HCC, but it can also indicate the regeneration of hepatocytes after massive hepatocyte necrosis, so the magnitude and dynamic changes of AFP elevation and its relationship with ALT and AST should be noted, and the patient’s clinical manifestations and liver ultrasonography and other imaging findings should be analyzed comprehensively.