Symptoms of purpura nephritis in children are mainly divided into renal manifestations and extra-renal manifestations. Renal manifestations are mainly hematuria, proteinuria, edema and hypertension, while extra-renal manifestations are mainly rash, joint swelling and pain, gastrointestinal symptoms, and so on. 1. Renal manifestations: hematuria and proteinuria are the main symptoms. Hematuria can be microscopic hematuria or microscopic hematuria, with microscopic hematuria as the main symptom. At the same time, there will be proteinuria of varying degrees, a large amount of proteinuria will appear edema, the site is often in the eyelids, ankles, etc., mainly depressed edema; reduced renal blood flow will appear renal hypertension. 2. Extra-renal manifestations: the rash is often symmetrically distributed on the legs, and in severe cases, it can spread to the buttocks and abdomen, etc. The rash is often bright red, and can be accompanied by itching, and usually recurs. Joint swelling and pain in the knee and ankle joints can occur. In addition, paroxysmal abdominal cramps can also occur, which can be accompanied by vomiting, vomiting blood, black stools, etc. Some other symptoms such as headache and myositis may also occur. If you suspect purpura nephritis in children, you must seek medical attention and treatment in time.