Purple spots on the skin mucosa is a condition in which blood spills between the skin and the skin shows bruised spots or patches. Purple spots are a sign of more bleeding under the skin. It starts with a reddish color and turns purple or yellow over time. In some people, a petechiae will appear on the local skin with a slight touch, and in some people, petechiae appear on the skin even without collision. This phenomenon is commonly seen in clinical practice, especially in women. It is called “simple purpura” when there are no other abnormal findings after various examinations, and sometimes it is the early manifestation of some bleeding disease, which is worth noting. The reason for the formation of mucosal purpura is that there are several aspects? Here is a summary of them. The causes of forming skin mucous membrane purple spots are the following three aspects: 1, thrombocytopenic purpura: these people have lower than normal platelets in blood. Because platelets are one of the more important factors in the blood coagulation mechanism, they are reduced to bleed easily. The more it is reduced, the more chances of bleeding. Most commonly seen in idiopathic thrombocytopenic violet palsy, aplastic anemia (platelet production disorder in bone marrow), leukemia (bone marrow is congested with leukemia cells, affecting platelet production), taking certain drugs, severe infections, hypersplenism caused by giant spleen, etc. 2, capillary lesions: due to capillary damage, blood is easy to leak out from capillary to subcutaneous cause purpura, more common for allergic purpura, can be caused by taking certain drugs, food or inhalation of certain substances. This kind of purpura distribution has the characteristic of bilateral symmetry. 3, coagulation disorder: there are more than 10 kinds of coagulation factors in human body, any kind of factor deficiency can be caused. Generally speaking, the recurrence of skin mucous membrane purpura in addition to simple purpura should be thought of thrombocytopenia, capillary lesions and coagulation disorders, it is recommended that patients must go to the hematology department for a comprehensive examination to avoid delaying the condition.