Autoimmune diseases are characterized by various factors that contribute to a breakdown in self-tolerance, that is, the ability of the immune system to effectively distinguish self from non-self and to refrain from attacking self. Autoimmune diseases include a broad spectrum of disorders, such as idiopathic thrombocytopenic purpura, systemic lupus erythematosus, rheumatoid arthritis, systemic sclerosis, and inflammatory bowel disease. Although significant progress has been achieved in the development of approaches to the treatment of autoimmune diseases, the etiologies, and pathogenesis of autoimmune diseases remain obscure (Tao et al., 2016) Immune thrombocytopenia (ITP) is an autoimmune bleeding disorder characterized by bleeding due to isolated thrombocytopenia with platelet count less than 100 × 109/L (Neunert et al., 2019).

ITP is classified based on course of disease into acute (3- <12 months), and chronic (≥12 months) (Provan et al., 2019). ITP usually has a chronic course in adults (Moulis et al., 2017) whereas approximately 8090% of children undergo spontaneous remission within weeks to months of disease onset (Heitink et al., 2018).

The main pathogenesis of ITP is the loss of immune tolerance to platelet auto-antigens, which results in increased platelet destruction and impaired thrombopoiesis by autoantibodies and cytotoxic T lymphocytes (CTLs) (Adiua et al., 2017).

Among these abnormalities include the increased number of the T helper 1 (Th1) cells (Panitsas et al.,2004). the decreased number or defective suppressive function of regulatory T cells (Tregs) (Yu et al., 2008) , and the

Inclusion Criteria:

• Patients with platelet less than 100 × 109/L diagnosed as immune thrombocytopenia according to bone marrow findings .

Exclusion Criteria:

• Other causes of thrombocytopenia as:

  • Hypersplenism.
  • Bone marrow diseases including : aplastic anemia, leukemia and myelodysplastic syndromes.
  • patients on chemotherapy and radiation therapy for cancer management