Liver impairment in children is a common condition, but it is not the same as what people usually call hepatitis. The general term hepatitis refers to viral hepatitis, i.e. hepatitis A, B, C, D, E and other hepatitis viruses that cause liver function impairment. There are various causes of liver function impairment in children, such as infectious diseases such as cytomegalovirus infection, EBV infection, hepatitis B virus infection, and septic liver injury caused by bacterial infection. There are also tuberculosis and fungal infections that can also cause liver function damage. Among non-infectious diseases, congenital disorders such as abnormal amino acid metabolism (Hitler’s protein deficiency, tyrosinemia), abnormal glucose metabolism (glycogen accumulation disorder), abnormal lipid metabolism and abnormal metal metabolism (hepatomegaly) are common in children. In addition, drug-related hepatitis is also common in children, because many drugs are metabolized by the liver, and children’s liver function is still immature, and some common cold and flu medicines and antipyretics can cause liver function damage. After finding liver function damage, thinking is not limited to liver function, but must also check cardiac enzymes, because a few children’s liver function damage from the abnormalities of cardiac enzymes, such as progressive muscular dystrophy, early symptoms are not typical, easy to miss or misdiagnosis.