Purpura kidney is the abbreviation of allergic purpura nephritis, allergic purpura is a common vascular allergic disease, because the body to some allergic substances to produce a metamorphic reaction, resulting in capillary permeability and increased fragility, vascular extravasation, producing purpura mucosa and some organs bleeding, but also can be accompanied by angioneurotic edema, and other allergic phenomena such as urticaria. Purpura kidney is the most severe condition, with an incidence of 12-40%. On the basis of cutaneous purpura, hematuria, proteinuria, and tubuluria, with occasional manifestations of edema, hypertension, and renal failure, occur because of the inflammatory glomerular capillary reaction. Renal damage mostly occurs 1 week after the appearance of purpura, or it can be delayed, mostly recovering within 3-4 weeks, and in a few cases it evolves into chronic nephritis or nephrotic syndrome due to recurrent attacks. Treatment, mainly with anti-allergy, elimination of allergy-causing factors, then is the application of glucocorticoids, which can inhibit the antigenic antibody response, reduce the inflammatory response exudation, improve the permeability of blood vessels. Generally, prednisone 30mg is used, and it is taken orally in daily doses or in divided doses, and can be extended at the discretion of the renal type.