Chronic eosinophilic leukemia with FIP1L1-PDGFRA.

A 37-year-old man with no significant past family or personal medical history was admitted to the hospital for persistent eosinophilia detected during a routine check-up. He denied recent travel and was not a smoker, alcoholic, or drug addict. He did not have any history of allergic disease and was not exposed to any toxins or pesticides. Physical examination was normal. His complete blood examination revealed hemoglobin 122 g/dL, total leukocyte count 9 109/L with an absolute eosinophil count of 6 109/L; platelet count was 200 109/L. A peripheral blood film showed many morphologic abnormalities of eosinophils, including of size, granulation, and nuclear lobulation (panels A-B). Red blood cells and platelets were normal and there were no circulating blast cells. The bone marrow exhibited 45% to 55% eosinophilic hyperplasia and 30% of myeloid blast cells (panel C; blue arrows show blast cells). Abnormal eosinophils with dysplastic granules were present.