Reactive Thrombocytosis Associated with Acute Myocardial Infarction following STEMI with Percutaneous Coronary Intervention

The etiology of thrombocytosis can be classified into reactive and essential forms. The rate of thromboembolic events is higher in essential thrombocytosis, and these events include strokes, transient ischemic attacks, retinal artery or retinal vein occlusions, digital ischemia, and acute coronary syndrome. In a study of 732 medical and surgical patients with thrombocytosis, 88% had reactive thrombocytosis. Patients with reactive thrombocytosis do not require cytoreductive medications or antiplatelet treatment. We report a healthy 40-year-old man without any medical problems who developed a new episode of myocardial infarction associated with thrombocytosis after an episode of myocardial infarction followed by percutaneous coronary intervention. He had thrombocytosis, and his platelet function test did not reveal adequate inhibition. To treat his acute coronary syndrome, therapeutic enoxaparin was added, and clopidrogel was substituted with ticagrelor. We decided to start hydroxyurea to reduce platelets counts. Enoxaparin and hydroxyurea were discontinued when platelet count returned to baseline. JAK-2 and BCR/ABL mutations were negative. This case report highlights a clinical dilemma (reactive thrombocytosis), which is challenging in terms of management and pathophysiology.