Clinical implications of elevated PAI-1 revisited: Multiple arterial thromboses in a patient with essential thrombocythemia and elevated plasminogen activator inhibitor-1 (PAI-1) levels: A case report and review of the literature

Plasminogen activator inhibitor (PAI-1), a member of the serine protein fam ily, is the most active in vivo inhibitor of fibrinolysis induced by tissue plasminogen activator (tPA), and urokinase type plasminogen activator (uPA ). While the association between elevated PAI-1 and thrombogenesis has been well studied for several disease processes, including coronary disease, po stoperative deep vein thrombosis (DVT), myocardial infarction, malignancy, and diabetes, few studies have concentrated on the correlation between elev ated PAI-1 levels and thrombogenesis in patients with myeloproliferative di sorders. Essential thrombocythemia (ET), a chronic myeloproliferative disor der, characterized by the overproduction of poorly functioning platelets, i s associated with both thrombotic and hemmorhagic life-threatening complica tions. Although the events resulting in thrombogenesis in such patients may be multifactorial in nature, an association between elevated PAI-1 levels and thrombus formation has been proposed. Herein we present a patient diagn osed with ET complicated by multiple episodes of arterial thrombosis. Eleva tions in PAI-1 levels were documented repeatedly. The role of elevated PAI- 1 when associated with other disease processes is also discussed.