Allergic purpura nephritis with urinary occult blood 3+ can be treated by improving lifestyle, medication and other ways. 1. Improvement of lifestyle: purpura fulminans is a kind of nephritis induced by purpura allergic, in the acute stage, there will be hematuria, proteinuria and so on, you should stop contacting any substances that can make the patient allergic to them, and fasting and so on if there is any gastrointestinal bleeding. 2. Drug treatment: Because the nephritis is caused by allergic purpura, chlorpheniramine maleate tablets can be taken orally for anti-allergy treatment; glucocorticosteroids such as prednisone and immunosuppressants such as cyclophosphamide can be used to improve renal function. 3. Other treatments: If there is no effective improvement after drug treatment, intravenous immunoglobulin or plasma exchange can be used if necessary. Patients with end-stage renal failure can be treated with dialysis and kidney transplantation. All of the above medications should be used under the guidance of a doctor to avoid self-medication. Patients with allergic purpura nephritis are advised to go to regular hospitals in a timely manner and receive standardized treatment under the guidance of a doctor.