Allergic purpura (HSP) is the most frequent vasculitis in childhood and is a systemic syndrome characterized by small vessel vasculitis. Most of them have a benign self-limiting course, but severe gastrointestinal, renal and other organ damage may occur. The most common infections of HSP are upper respiratory tract infections caused by group A beta-hemolytic streptococci, and infections such as Helicobacter pylori (HP) and Staphylococcus aureus may also be a cause of HSP. Other pathogens, including Mycoplasma pneumoniae, may have some relevance to the occurrence of HSP. Vaccination: Some vaccinations such as influenza vaccine, hepatitis B vaccine, rabies vaccine, influenza vaccine, diphtheria vaccine, measles vaccine have been reported in the literature as possible causes of HSP, but reliable research evidence is needed. Food and drug factors Food and drug factors: Some cases have reported that the use of certain drugs such as clarithromycin, cefuroxime, minocycline, ciprofloxacin, diclofenac, propylthiopyrimethamine, hydrazinopyridazine, allopurinol, phenytoin sodium, carbamazepine, isotretinoin, cytarabine, adalimumab, etanercept, etc. may also trigger the occurrence of HSP. There is no clear evidence that food allergy can cause HSP. Although there is no strong evidence that diet can trigger allergic purpura, it does not mean that diet will not trigger it. It is not uncommon for us to encounter food-induced allergies and even allergic purpura in our clinical work. Therefore, I suggest that people with allergic purpura pay attention to what environmental factors are related to their condition. For example, some patients said they had belly pain and spots on their hands, feet and body after consuming purpura before, so they should be careful about eating purpura in the future, and so on. And for the usual eaten and no discomfort food need not be abstained from eating.