Plasma replacement is a new blood purification therapy that separates the patient’s blood into plasma and blood cell components outside the body, discards the plasma, and then transfuses the cell components back into the body together with the replacement fluid in the same amount as the discarded plasma, so as to remove pathological substances (such as autoantibodies, immune complexes, high-precision substances and protein-bound toxic substances) to achieve a variety of diseases for which general therapy is ineffective. It can be used for: 1. Kidney diseases: pulmonary hemorrhagic nephritis syndrome, lupus nephritis, purple epilepsy nephritis, IgA nephropathy, membrane proliferative nephritis and acute rejection of transplanted kidney especially vascular rejection. These diseases cannot be completely controlled by hormones and other immunosuppressive agents. Plasma exchange can remove anti-glomerular basement membrane antibodies, anti-nuclear antibodies and various autoantibodies, immune complexes and inflammatory products accompanying the immune response, resulting in improvement of clinical symptoms, renal function and histological changes. It is not effective in cases where renal failure has already occurred.2. Systemic diseases: systemic lupus erythematosus, polyarteritis nodosa, dermatomyositis, rheumatoid arthritis, etc. are diseases for which no special therapy is available. Plasma replacement therapy can remove various autoantibodies and immune complexes to improve clinical symptoms, and is suitable for patients with severe diseases in which hormones and immunosuppressants are ineffective or ineffective and life-threatening. However, the maintenance time alone is short and should be combined with immunosuppressants to control the progress of the disease.3. Hematological diseases: autoimmune hemolytic anemia, hemolytic uremic syndrome, thrombotic thrombocytopenic purple epilepsy, hyperviscosity syndrome, etc., have a higher chance of improvement.4. Neurological diseases: diseases for which plasma replacement is indicated include myasthenia gravis, polyneuritis, neurological damage in systemic lupus erythematosus and Plasma replacement can quickly remove harmful factors from the plasma and minimize the damage to neural tissue, thus enabling the patient to be out of danger soon.5. Acute and chronic liver failure: such as fulminant hepatitis, drug poisoning, surgery or trauma, biliary cirrhosis, hepatic coma, etc. The earlier plasma exchange starts treatment, the better the prognosis.6. Familial hypercholesterolemia: It is a common indication for plasma exchange, which can inhibit the progression of atherosclerosis and even completely subside. Therefore, plasma replacement can prevent atherosclerosis.