We report a case of 48 year old male with no significant past medical history, presented to hospital with complaint of left arm weakness and dysarthria that started 2-3 hours before. He had an episode of left leg weakness for 15-20 minutes, 2 weeks ago which completely resolved. Review of system was negative for palpitation, chest pain, shortness of breath, headache, blurred vision, dysphagia and facial deviation. His neurological exam was completely benign on presentation. Cardiovascular, pulmonary and extremities examinations were also unremarkable. The patient was approached as a possible case of transient ischemic attack (TIA). ECG, Echo, carotid US and non contrast CT of brain were all normal. CBCD showed WBC 8.0, Hb of 13.0, Platelets 1092, large and giant platelets but absence of teardrop cell, immature blasts and nucleated RBC in peripheral smear. Patient denied any crush injury, infection, recent surgery, acute blood loss and splenectomy. Coagulation panel including PTT, INR and fibrinogen were within normal range. Other electrolytes, liver function, troponin, ESR, CRP and iron panel with ferritin were within normal limits. A diagnosis of thrombocytosis associated with ET was made. He was subsequently tested positive for calreticulin and JAK2 mutations.He was started on low dose aspirin and hydroxyurea and platelet counts declined to < 400,000/microL over next 1 week .
Thrombocytosis is defined as a platelet count greater than 450,000/microL. Approach to a patient of thrombocytosis includes differentiating reactive thrombocytosis from myeloproliferative neoplasm and assessing the imminent risk from elevated platelet counts. Essential thrombocythemia (ET) is one of the myeloproliferative neoplasms that presents with thrombocytosis but it is only diagnosed after excluding other myeloproliferative neoplasms including polycythemia vera (PV), chronic myeloid leukemia (CML) and myelofibrosis (PMF). Thrombosis and hemorrhage are common complications of ET, likely due to qualitative and quantitative platelet alterations. Some of the rare thrombotic events associated with thrombocytosis include stroke, TIA, myocardial ischemia, venous thrombosis, pulmonary embolism and digital gangrene. Our patient had normal hemoglobin and hematocrit, negative bcr-abl fusion, ruling out PV and CML as initial diagnosis. Absence of splenomegaly, immature cells of the granulocyte series, and tear drop-shaped red cells in the peripheral blood made diagnosis of PMF unlikely.
ET patients with age > 60 years, H/O thrombosis including stroke, TIA and pulmonary embolism and platelet count > 1 million/ micro are considered to be moderate to high risk. Such patients should be started on aspirin and hydroxyurea. The other treatment options to treat thrombocytosis include interferon, anagrelide and plateletpheresis.
To cite this abstract:Ghosh R, Ravakhah K, Reisman J. One Million Platelets and Transient Ischemic Attack: How Do You Manage?. Abstract published at Hospital Medicine 2015, March 29-April 1, National Harbor, Md. Abstract 528. Journal of Hospital Medicine. 2015; 10 (suppl 2). https://www.shmabstracts.com/abstract/one-million-platelets-and-transient-ischemic-attack-how-do-you-manage/. Accessed March 28, 2020.