Renal purpura is generally referred to as renal-type allergic purpura, a common vasovagal allergic reaction disease, mainly manifested as skin damage on the basis of concomitant renal damage. Henochromic purpura is a common vascular allergic reaction disease, due to the body’s allergic reaction to certain sensitizing substances, resulting in increased capillary fragility and permeability, blood extravasation, resulting in purpura, mucous membranes and certain organs bleeding. It may be accompanied by other allergic manifestations such as angioneurotic edema and urticaria. Renal purpura is a type of allergic purpura. In addition to the presence of skin purpura, renal damage may occur, with hematuria, proteinuria, and tubular urine due to the inflammatory reaction of glomerular capillary collaterals, and occasional manifestations such as edema, hypertension, and renal failure. Renal damage occurs 2 to 4 weeks after the appearance of purpura, or delayed appearance. Most patients can recover completely, and a few cases evolve into chronic nephritis and renal insufficiency due to recurrent episodes. Nephrogenic purpura often manifests as symmetrical purpura of varying sizes on the extremities, and may be accompanied by renal damage such as hematuria, proteinuria and tubular urine. Some patients may also have edema, hypertension, renal failure and so on. It is recommended that patients with renal purpura should consult a doctor if they feel unwell, and follow the doctor’s instructions for standardized diagnosis and treatment.