Efficacy of Rapamycin Therapy With Chronic Immune Thrombocytopenia

Rapamycin, an immunosuppressive drug, is widely used to prevent allograft rejection and autoimmune diseases. Many studies have shown that the drug contributes to the expansion of regulatory T cells and preserves the highly suppressive function of autoreactive T cells. Patients with RITP often display a decreased proportion of regulatory T cells by flow cytometer, therefore, the investigators will examine the efficacy of rapamycin in RITP patients.