الفهرس 
IntroductionOnly 14 pages are availabe for public view
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Abstract
Thrombocytopenia (ITP) is a common autoimmune disorder characterized by isolated thrombocytopenia. ITP may appear in the form of primary or secondary for other diseases, such as recurrent infections. ITP incidence varies from 2 to 5 over 100,000 children under 15 years old. An international working group (IWG) of professionals has set up platelets count below 100,000 / mm3 as a diagnostic threshold. According to IWG, ITP has been classified as recently diagnosed or acute (within 3 months of diagnosis), persistent (from 3 to 12 months) and chronic (lasting more than 12 months). Many studies have reported associations between ITP and single nucleotide polymorphisms (SNP) in immunity-related genes. Polymorphisms in genes encoding specific cyto- or chemokines, such as interleukin (IL)-1, IL-2, IL-4, IL-6, IL-10, IL-17, and TNF-α, TGF-β, and IFN-γ, have been associated with ITP. Several studies have also investigated whether specific HLA class I or II alleles might be elevated in patients with ITP. Dysfunction of T cells in ITP may be contributed to loss of tolerance, and impairment of the delicate balance of specific cytokines and serum cytokines may play a role in the pathogenesis of ITP. T lymphocytes polarize into helper T-1 response characterized primarily by the presence of cytokines interleukin (IL)-2, interferon-γ, and tumor necrosis factor (TNF)-α and helper T-2 response produces IL-4, IL-5, IL-6, IL-10, and IL-13. Understanding the role of T-cell subsets will permit a better control of autoimmunity through manipulation of their cytokine network. Dysfunction at cellular immunities is evaluated by the levels of cytokines, e.g., TNF-α and IL-6. Measurement of levels of cytokines may help in prediction of the course of ITP. Some studies reported that IL6-572G>c=rs1800796 and IL10 - 627A>C=rs1800872 polymorphisms were associated with the pathogenesis of ITP and contributed to the susceptibility of developing ITP, and that this could be the basis for immunomodulatory therapies for ITP and provide a tool for early diagnosis of susceptibility to ITP.