Extreme Thrombocytosis not always Essential Thrombocythemia BCR-ABL has to be Done Timely

Abstract

Abstract: Chronic Myeloid Leukemia (CML) is a myeloproliferative neoplasm in which the major proliferative component is comprised of granulocytes and is characterized by translocation of BCR-ABL and formation of Philadelphia (Ph) chromosome. Extreme thrombocytosis in chronic myeloid leukemia is rare and mimic essential thrombocythemia. Thus, chronic myeloid leukemia should be ruled out in patients who present with extreme thromobocytosis. A 28 years old female presented to us with abdominal discomfort, bleeding gums and hematuria. Her past medical history was unremarkable and there wasn’t any family history of bleeding disorder. On examination she had pallor and splenomegaly. Laboratory studies showed thrombocytosis with platelet count of 6420 x 10^9/L , moderate leucocytosis of 22.8 x 10^9/L along with low hemoglobin of 7.9 g/dL. Workup for acquired von willebrand disease was done which showed vWF: Ag 94%, vWF: Ricof 30%, FVIII 75%. Her cyto reduction with hydroxycarbamide 3g/day was started and patient was proceeded for platelet pheresis. On follow up after two sessions of platelet pheresis her platelet count was still high 3104 x 10^9/L. JAK2V617F, MPL, CALR and BCR-ABL mutations were checked and she turned out to be BCR-ABL positive, rest of the mutations were not detected. Bone marrow biopsy findings were consistent with chronic myeloid leukemia in accelerated phase along with marked proliferation of megakaryocytes present in sheets. Anagrelide was administered to control thrombocytosis and nilotinib 800mg/day was started. Although chronic myeloid leukemia can present with thrombocytosis but platelet count exceeding 1000 x 10^9/L is rare. Our patient demonstrated very high count of platelets (6420 x 10^9/L) and relatively unremarkable white cell count. Most of the symptoms she had were due to thrombocytosis rather than leucocytosis as typically seen in chronic myeloid leukemia.