 At screening, plasma will be separated from patients venous blood 400ml aseptically and autologous immunoglobulin fraction will be purified from the plasma by chromatography using Protein A during the screening period. Patients will be randomized in a 1:1 ratio to receive weekly treatment with autologous immunoglobulin or placebo normal saline for 2 months will be administrated by intramuscular injection, once a week for 7 weeks total 8 injections. 