hematology and oncology
Polycythemia Vera
Key Points
Polycythemia vera is a chronic myeloproliferative neoplasm that involves increased production of red blood cells, white blood cells, and platelets. Polycythemia vera is due to mutations involvingJAK2, or rarely theCALRorLNKmutations in hematopoietic stem cells that lead to sustained activation of JAK2 kinase, which causes excess blood cell production. Complications include thrombosis, bleeding, and hyperuricemia; some patients eventually develop myelofibrosis or rarely transformation to acute leukemia. Polycythemia vera is often first suspected because of an elevated hematocrit level; neutrophils and platelets are usually, but not invariably, increased. Test forJAK2,CALR, orLNKmutations. Bone marrow aspirate and biopsy and a serumerythropoietinlevel are usually not useful diagnostically. Phlebotomy to target hematocrit < 45% in men and < 42 % in women patients is essential. Ruxolitiniband pegylated interferon are the preferred myelosuppressants. 