Complex Arterial and Venous Thrombosis in Polycythemia Vera: what Does Leukocytosis Predict?

Thromboembolic events represent the main cause of morbidity and mortality in patients with polycythemia vera. Leukocytosis has been identified as an important risk factor for development of vascular thrombosis. A 47-year-old woman with polycythemia vera presented with pain and swelling in her right calf. She was scheduled to receive anagrelide which was effective on polycythemia and thrombocytosis, but leukocytosis persisted. She was diagnosed with thrombosis in right popliteal vein and left common femoral vein by duplex ultrasonography. We suggested a role for leukocytosis in inducing thrombotic phenomenon in our patient with polycythemia vera.