Disease Overview for Chronic Eosinophilic Leukemia (CEL)

CEL is a chronic myeloproliferative neoplasm of unknown etiology in which a clonal proliferation of eosinophilic precursors results in persistently increased numbers of eosinophils in the blood, bone marrow, and peripheral tissues. In CEL, the eosinophil count is greater than or equal to 1.5 × 109/L.[1] To make a diagnosis of CEL, there should be evidence for clonality of the eosinophils or an increase in blasts in the blood or bone marrow. However, in many cases, it is impossible to prove clonality of the eosinophils, in which case, if there is no increase in blast cells, the diagnosis of idiopathic hypereosinophilic syndrome (HES) is preferred. Because of the difficulty in distinguishing CEL from HES, the true incidence of these diseases is unknown, although they are rare. In about 10% of patients, eosinophilia is detected incidentally. In others, the constitutional symptoms found include:[1,2]

No single or specific cytogenetic or molecular genetic abnormality has been identified in CEL.

For more information about the symptoms listed above, see Hot Flashes and Night Sweats, Fatigue, Cardiopulmonary Syndromes, Pruritus, and Gastrointestinal Complications.