الفهرس 
IntroductionOnly 14 pages are availabe for public view
 |  | from | 136 |  |  |
| | | from | 136 | | |
Abstract
Introduction
Childhood immune thrombocytopenic purpura (ITP) is one of the most common benign hematologic disorders, which is characterized by the isolated, immune-mediated thrombocytopenia and mucocutaneous bleeding.
Acute ITP in children is typically a self-limited disorder that resolves within several weeks to months. However, approximately 20%–30% of children have persistent thrombocytopenic states for more than 6–12 months, which is called the chronic ITP.observation alone may be appropriate therapy, even in children with severely low platelet counts , given that the risk of serious or life threatening bleeding is low.
The bleeding diatheses are, however, very hetrogenous, and it is still unclear why patients with similar platelet counts can present with different clinical bleeding manifestations.
To maintain the immune tolerance and to prevent autoimmune disease, CD4+ and CD25+ regulatory T cells (Treg), play a fundamental role.
Decreased number of Tregs and impairment of Tregs function have been reported in patients with various autoimmune diseases, such as systemic lupus erythematosus, rheumatic arthritis, multiple sclerosis, and diabetes as well as immune thrombocytopenic purpura.
There have been increasing amount of evidences indicating that an impairment of regulatory T cells play a critical role in pathogenesis of ITP.
Aim of the work
This study aims to determine the possible role of regulatory T cells as a part of cell mediated immunity in pathogenesis of childhood immune mediated thrombocytopenia.
Subjects and methods
This cross sectional study was conducted on 40 children who were diagnosed as ITP and 20 apparently healthy children as control. They were grouped as follow:
group Ⅰ:
It included 20 patients with newly diagnosed ITP, 12 males and 8 females.
group Ⅱ:
It included 20 patients with chronic ITP, 10 males and 10 females.
group Ⅲ:
It included 20 apparently healthy children as control, 9 males and 11 females.
All subjects included in the study were subjected to the following:
1- Through history taking:
2- Clinical examination:
3- Laboratory investigations:
CBC.
Bone marrow examination (for patients only).
CD4+ and CD25+ T lymphocyte enumeration by flow cytometry.
Results of 3 groups were summarized as follows:
There was significant decrease in Treg in newly diagnosed and chronic groups when compared to control group.
The results suggest that decreased number of Regulatory T cells in children might be one of the mechanisms that cause immune dysregulation in ITP, so it might play a role in the pathogenesis of immune mediated thrombocytopenia.