Study of IL4 in Acute and Chronic ITP in Pediatric Patients

Abstract

Summary I mmune thrombocytopenic purpura (ITP) is an acquired autoimmune disorder and the most common cause of isolated thrombocytopenia in children. It is diagnosed clinically, based upon onset of thrombocytopenia in the absence of other hematologic abnormalities, or other causes of low platelets. ITP is caused by the production of antiplatelet antibodies. These autoantibodies opsonize platelets for splenic clearance, resulting in low levels of circulating platelets. Impaired platelet production and T cell–mediated effects also play a role in the pathogenesis of the disease. Dysfunctional cellular immunity is evaluated by the level of the cytokines at the site of immune activation. Naive Th cells can differentiate into Th1 or Th2 cells. The balance of Th1 and Th2 cells regulates the immune system under normal conditions and is critical in the pathogenesis of autoimmune diseases including RA, inflammatory bowel disease, type 1 diabetes, MS, SLE, and ITP, in which a predominance of Th1 can induce autoimmunity, whereas a Th2 predominance can inhibit autoimmunity. Interleukin-4 is a Th2-type cytokine involved in many immunemodulating functions on a variety of cell types, such as the activation and differentiation of T-dependent B cells and antibody isotype switching from IgM⁄ IgG to IgE. This study aimed to investigate the role of serum level of IL-4, as a marker for prediction of ITP chronic progression in children.It also aimed to compare bleeding score and lymphocytic count between acute and chronic ITP patients. This study was a cross-sectional study and was conducted in Ain shams university pediatric hospital hematology Clinic. It included 20 newly diagnosed ITP patients(36.4%)and 15 chronic ITP(27.3%) patients and 20 control individuals(36.4%). The patients were subjected to detailed history with special emphasis on bleeding score,detailed examination and investigation including complete blood count (CBC) with absolute lymphocytic count; we applied measuring serum level of IL4 by ELISA technique. There was a highly statistically significant difference between the three groups regarding level of IL4 with higher level in acute patients in comparison to chronic patients and controls,also there is statistically significant increase in IL4 level in chronic patients in comparison to controls.