Serum aminotransferases exist in the liver and can reflect whether liver cells are damaged or not. When liver cells are damaged and degeneration and necrosis occur, aminotransferases are significantly increased, therefore, serum aminotransferases are often used clinically as an important indicator to determine abnormal liver function. 1.The higher the transaminase level, the more serious the damage to the liver? In fact, this is not true, and specific analysis is needed for different diseases. In most patients with acute hepatitis, the elevated level of serum aminotransferases is positively correlated with the degree of liver cell damage, but in patients with cirrhosis, liver cancer, liver failure and chronic viral hepatitis, the level of serum aminotransferases does not truly reflect the severity of liver damage. Patients with cirrhosis of all causes, whether in the compensated or decompensated phase, can have normal transaminase levels. Patients with liver failure can have “bile enzyme separation”, meaning that serum transaminases can be normal, but bilirubin is consistently elevated, often indicating a poor prognosis. Patients with hepatocellular carcinoma may also show normal transaminases even during the progressive phase of the disease. In some patients with chronic viral hepatitis, transaminase levels are normal during the immune tolerance period, but the damage to hepatocytes is progressive. 2. The higher the level of transaminases, the more infectious hepatitis B is? The infectiousness of hepatitis B patients is not determined by the level of aminotransferases, and it may even be the opposite, the higher the level of aminotransferases, the less infectious it may be. The higher the transaminase level, the less contagious the patient may be. This is because the hepatitis B virus is cleared by the body’s immune cells at the same time as the hepatitis B cells are attacked and destroyed. In fact, the infectiousness of hepatitis B depends on the amount of virus in the patient’s blood and body fluids and the active level of virus replication in the body, but not on the level of aminotransferases.