Anaphylactic purpura is not caused by allergy. Many people think that anaphylactic purpura is caused by allergy because it was originally called anaphylactic purpura. In fact, on a medical level, purpura is an IgA-mediated systemic vasculitis and is not caused by allergy. Allergic purpura is an IgA-mediated vasculitis that can cause systemic manifestations, most commonly skin purpura, which can be seen with the naked eye; in addition, joint symptoms and gastrointestinal symptoms can be seen; you should also be aware that allergic purpura may cause renal damage, as well as other aspects of the manifestations. Allergic purpura that is simple skin purpura, we should not be too nervous, allergic purpura acute stage is the most important thing is to pay attention to the joint symptoms and digestive symptoms, pay attention to the digestive tract hemorrhage; the late main concern is that purpura is very easy to recur, but also can cause kidney damage, you should pay attention to these aspects.