Level of CD11a among Newly Diagnosed ITP Patients and after 6 Months Follow Up

Abstract Background and Objectives Immune thrombocytopenia (ITP) is a relatively frequent acquired bleeding disorders. Etiology is not yet well understood. Lymphocytic function associated antigen-1(LFA-1) might play an important role in signal coordination and lymphocyte activation. The aim of this study was to assess CD11a expression on lymphocytes in newly diagnosed ITP patients and to correlate it with bleeding severity in ITP and to evaluate the effect of immunomodulation medications on CD11a expression in children with ITP. Patients and Methods This is a prospective case-control study enrolling children with ITP attending pediatric Hematology clinic, Ain Shams University Hospitals through November 2021-November 2022 and near equal number of age and sex matched control subjects were randomly selected. All necessary laboratory tests for diagnosis of ITP were performed and the expression of CD11a on lymphocytes was analyzed by flow cytometry at the start of the study and after 6 months of follow up and assessment of bleeding manifestations according to ITP- specific bleeding assessment tool (ITP-BAT). Results Thirty-five patients aged (2-15) years with median age 6.5 years. 21 males and 14 females were enrolled as newly diagnosed primary ITP. The mean platelet count in these patients was 13(103/ul) initially and 239(103/ul) at follow up with response rate of 94.1%. The treatment received in ITP patients was corticosteroid (97.1%),IVIG (11.6%),thrombopoietin receptor agonist (17.4%) and anti CD20 monoclonal antibody (5.8%). The mean fluorescence intensity (MFI) of CD11a was 95.7% initially and 94.7 % at follow up and it was 94.3% in the control group. The mean fluorescence intensity (MFI) of CD11a on lymphocytes showed significant difference in ITP patients initially compared to healthy controls (p value= 0.001) and (MFI) of CD11a on lymphocytes show significant difference between patients before and after treatment (p value=0.001). Conclusion CD11a had a possible role in the pathogenesis of ITP. Immune-modulatory therapy for ITP affects the level of CD11a expression on lymphocytes. CD11a expressions on lymphocytes were not correlated with the platelet counts nor the bleeding score in ITP.