Persistent Eosinophilia: A Diagnostic Dilemma

  • Hafsa Shabeer Kempegowda Institute of Medical Sciences, Bangalore
  • Chethana Mannem Kempegowda Institute of Medical Sciences, Bangalore
  • Gayathri Bilagali Ramdas Kempegowda Institute of Medical Sciences, Bangalore
  • Thejasvi Krishnamurthy Kempegowda Institute of Medical Sciences, Bangalore
Keywords: Eosinophilia, chronic eosinophilic leukaemia, idiopathic hypereosinophilic syndrome


Chronic eosinophilic leukaemia-not otherwise specified (CEL-NOS) is a myeloproliferative neoplasm associated with an autonomous, clonal proliferation of eosinophilic precursors resulting in persistent eosinophilia. A 50-year-old female presented with easy fatiguability, cough and generalised swelling of the body. Investigations revealed anaemia with leucocytosis (56.150 x 103/ul) and 88% eosinophils (absolute eosinophil count was 49412/ul). Peripheral smear showed abnormal eosinophils exhibiting abnormal granulation and nuclear lobation. Reactive causes were ruled out and a bone marrow aspiration/biopsy revealed mildly hypercellular marrow with increased number of eosinophils and their precursors, 7% blasts along with dysplastic megakaryocytes - hypolobated and occasional segmented forms. Molecular studies including chromosomal and gene analysis were done. A combination of the clinical picture, laboratory and molecular studies led us to a diagnosis of CEL-NOS. The causes for eosinophilia are myriad and range from reactive causes like parasitic infestations to neoplasms in which eosinophils are a part of the neoplastic population/ are cytokine-mediated reactive component in the background of another neoplasm. The incidence of CEL-NOS is obscure due to significant overlap with Idiopathic Hypereosinopihlic eosinophilia (IHES). While CEL-NOS is a myeloproliferative neoplasm and its diagnosis can be made provided evidence of a clonality is present, IHES is a diagnosis of exclusion. It is important to differentiate the two entities as they carry different prognosis and modes of treatment.

Author Biographies

Chethana Mannem, Kempegowda Institute of Medical Sciences, Bangalore
Associate Professor, Department of Pathology.
Gayathri Bilagali Ramdas, Kempegowda Institute of Medical Sciences, Bangalore
Tutor Department of Pathology
Thejasvi Krishnamurthy, Kempegowda Institute of Medical Sciences, Bangalore
Associate Professor, Department of Pathology.


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