Lactate dehydrogenase is widely found in various organs of the human body, with heart, skeletal muscle and kidney being the most abundant. Lactate dehydrogenase is a glycolytic enzyme, which mainly catalyzes the re-metabolism of lactic acid. It is widely distributed in the cytoplasm of cells of the liver, heart, skeletal muscle, lung, spleen, brain and other tissues, and can be used in liver diseases and malignant tumors ref. Lactate dehydrogenase is the main enzyme in the glycolytic pathway, and lactate dehydrogenase catalyzes the oxidation of lactate into pyruvate. Lactate dehydrogenase is elevated when inflammation, infection, and hemorrhage occur, which has some clinical significance. Common conditions in which lactate dehydrogenase is elevated include myocardial infarction, hepatitis, malignancy, leukemia, hemolytic anemia, and kidney disease. Lactate dehydrogenase is only an auxiliary diagnostic index, and should be combined with clinical symptoms and other tests to make a comprehensive judgment.