Acute lymphoblastic leukemia with eosinophilia: diagnostic and treatment features

Acute lymphoblastic leukemia (ALL) manifested by eosinophilia (1.5 × 109/L) in peripheral blood is extremely rare, less than 1 % of all ALL cases. A characteristic feature of patients with ALL and eosinophilia is the absence of blasts in the peripheral blood, which can make early diagnosis of ALL difficult. The article describes the clinical case of 2-year-old patient with ALL and eosinophilia. due to the wide variety of etiologic factors of eosinophilia, which include allergic, infectious, immune agents, and a high risk of developing severe lesions of internal organs, physicians should conduct a broad differential diagnosis with the mandatory inclusion of malignant neoplasms in the diagnostic series. precise determination of the etiology of eosinophilia allows the correct diagnosis and etiotropic treatment.