Plasminogen Activator Inhibitor 1 in Patients with Primary Immune Thrombocytopenia: A Case Control Study

Primary immune thrombocytopenia (ITP) is a condition associated with decreased platelet count plus subsequent high risk of bleeding. Many studies mentioned that ITP also has a higher risk of developing thrombosis, which may have a significant influence on the disease management. Plasminogen activator inhibitor-1 (PAI-1), a fibrinolysis inhibitor, is implicated within the procoagulant state of ITP patients. To assess the PAI-1 serum level in ITP patients, non-immunologic thrombocytopenia controls (TC) and healthy controls (HC), and to correlate PAI-1 level with clinical variables. Serum PAI-1 was measured by ELISA in 45 ITP patients, 22 TC and 22 HC. All participants were subjected to complete clinical assessment and examination. Bleeding severity was assessed using SMOG bleeding score. Levels of PAI- 1 were discovered to be significantly higher in ITP patients compared to TC and HC with a high significant difference between the three groups with p value < 0.0001. Only three ITP patients developed thrombosis. PAI-1 level showed no significant relation with platelet count, SMOG bleeding score, thrombosis, treatment with thrombopoietin agonists (TPO RA) and splenectomy. Primary ITP patients showed significantly higher PAI-1 level compared to non-immunologic thrombocytopenic patients and healthy controls. This finding may help in understanding the suggested increased thromboembolic risk in ITP patients. However, no association with bleeding score and risk of thrombosis was found in this study.