Abnormal prothrombin is also known as abnormal coagulation factor II, which is the most important type of clotting factor in the body. A high level of abnormal prothrombin, or abnormal coagulation factor II, is a concentration of abnormal coagulation factor II that exceeds normal levels. There are two common causes of abnormally high levels of coagulation factor II in clinical practice: 1. Patients with vitamin K deficiency, because vitamin K is a coenzyme agent for the synthesis of coagulation factor II. When vitamin K is deficient, the body is unable to synthesize coagulation factor II normally, but can only synthesize abnormal coagulation factor II, and there is a situation of elevated abnormal coagulation factor II. 2. In patients with chronic liver disease, because the function of the liver to synthesize coagulation factors is reduced, only abnormal coagulation factors can be synthesized at this time, which means there is a situation of elevated abnormal coagulation factor II. With increased abnormal prothrombin in the human body, there will be a decrease in coagulation function, which makes it easier for various bleeding symptoms to occur, which can be manifested as petechiae on the skin, and in some cases even as internal bleeding and a series of other conditions.