First, the most common is hepatocellular jaundice, that is, hepatitis leading to impaired liver function, in which case bilirubin is usually elevated in both direct and indirect bilirubin; second, obstruction of the extrahepatic bile duct, commonly bile duct stones, tumors of the jugular abdomen, tumors of the head of the pancreas, etc., in which case total bilirubin is elevated in direct Thirdly, another rare condition is the increase of indirect bilirubin, which is usually seen in Gilbert’s syndrome; fourthly, there are also some indirect bilirubin increases caused by hemolysis due to blood system diseases.