Chronic eosinophilic leukemia

Chronic eosinophilic leukaemia (CEL) is a rare myeloproliferative disorder of unknown etiology characterized by an autonomous, clonal proliferation of eosinophilic precursors resulting in persistently increased number of eosinophils in the peripheral blood and bone marrow. There is vaguely overlapping clinico – pathological picture of CEL with idiopathic hypereosinophilic syndrome (HES) which often adds to the diagnostic confusion. An evidence of genetic clonality of eosinophils or an increase in blast cells in the blood or bone marrow is mandatory for diagnosis of CEL, while no specific diagnostic tests exist for HES; making it an entity of exclusion. A 41-year old male patient presented with low grade fever associated with drowsiness and heaviness of head since four days and sudden onset of weakness of left lower limb was subjected for complete haemogram followed by bone marrow examination in addition to routine biochemical and radiological evaluation. The peripheral smear and bone marrow aspirates were dominated by the presence of eosinophilic precursors with striking presence of eosinophiloblasts associated with eosinophilic myelocytes, metamyelocytes, a few myeloblasts and basophils compromising erythroid and megakaryocytic elements, the features of which are in favour of CEL. Till date, CEL is a rarely reported entity from India and its presentation with neurological manifestations is still rare. We add yet another case of CEL along with review of available literature.