The life span of human red blood cells is usually 120 days. After death, red blood cells become indirect bilirubin (I-Bil), which is converted into direct bilirubin (D-Bil) by the liver, forming bile, which is excreted into the bile duct and finally excreted through the stool. The sum of indirect bilirubin and direct bilirubin is total bilirubin (T-Bil). A disruption in any of the above can cause a person to become jaundiced. Hemolytic jaundice can occur if too much red blood cells are destroyed and too much indirect bilirubin is produced, which the liver cannot completely convert into direct bilirubin; hepatocellular jaundice occurs when liver cells are diseased, because bilirubin cannot be converted into bile properly, or when the bile ducts in the liver are pressurized and the excretion of bile is blocked due to swelling of liver cells, which raises the bilirubin in the blood; once the extrahepatic biliary system Once a tumor or stone occurs in the extrahepatic biliary system, the bile ducts are blocked and bile cannot be excreted smoothly, and obstructive jaundice occurs. In patients with hepatitis, jaundice is usually hepatocellular jaundice, and both direct and indirect bilirubin are elevated, while in patients with biliary hepatitis, direct bilirubin is mainly elevated. 1, high direct bilirubin, if the liver cells are damaged, bilirubin can not be converted into bile normally, or bile excretion is obstructed, can cause high direct bilirubin, the common causes of high direct bilirubin are intrahepatic and extrahepatic obstructive jaundice, pancreatic head cancer, capillary bile duct type hepatitis and other bile stasis syndrome; 2, total bilirubin, direct bilirubin, indirect bilirubin are increased: acute jaundice, hepatitis chronic active hepatitis, hepatic steatosis, toxic hepatitis, etc. 3.Total bilirubin and direct bilirubin are increased: intrahepatic and extrahepatic obstructive jaundice, pancreatic head cancer, capillary bile duct type hepatitis and other bile stasis syndromes, etc. 4.Increased total bilirubin and indirect bilirubin: hemolytic anemia, blood type incompatibility transfusion, malignant disease, neonatal jaundice, etc. 5, erythrocyte rupture factors: damage to the liver can lead to the rupture of a large number of erythrocytes in the liver of patients with hepatitis B. When the metabolic function of the liver is not enough to make its conversion into direct bilirubin, it can trigger the symptoms of hemolytic jaundice. 6, hepatocyte lesion factors: when the hepatocytes of patients with hepatitis B lesions, or bilirubin can not be converted into bile, can lead to liver enlargement, intrahepatic bile ducts are compressed and cause impaired bile excretion, resulting in increased bilirubin content in the blood. 7, bile excretion obstruction factors: such as hepatitis B patients suffering from gallstones, gallstones can block the excretion of bile in the liver, so that the bile can not be smoothly excluded from the liver, which can also lead to an increase in bilirubin in the blood.