World Health Organization ‐defined eosinophilic disorders: 2017 update on diagnosis, risk stratification, and management

Abstract
Disease overviewThe eosinophilias encompass a broad range of nonhematologic (secondary or reactive) and hematologic (primary, clonal) disorders with potential for end‐organ damage.
DiagnosisHypereosinophilia has generally been defined as a peripheral blood eosinophil count greater than 1500/mm3 and may be associated with tissue damage. After exclusion of secondary causes of eosinophilia, diagnostic evaluation of primary eosinophilias relies on a combination of morphologic review of the blood and marrow, standard cytogenetics, fluorescent in situ‐hybridization, flow immunocytometry, and T‐cell clonality assessment to detect histopathologic or clonal evidence for an acute or chronic myeloid or lymphoproliferative disorder.
Risk stratificationDisease prognosis relies on identifying the subtype of eosinophilia. After evaluation of secondary causes of eosinophilia, the 2016 World Health Organization endorses a semi‐molecular classification scheme of disease subtypes which includes the major category “myeloid/lymphoid neoplasms with eosinophilia and rearrangement of PDGFRA, PDGFRB, or FGFR1 or with PCM1‐JAK2,” and the “MPN subtype, chronic eosinophilic leukemia, not otherwise specified” (CEL, NOS). Lymphocyte‐variant hypereosinophilia is an aberrant T‐cell clone‐driven reactive eosinophila, and idiopathic hypereosinophilic syndrome (HES) is a diagnosis of exclusion.
Risk‐adapted therapyThe goal of therapy is to mitigate eosinophil‐mediated organ...

Source: American Journal of Hematology - October 17, 2017 Category: Hematology Authors: Jason Gotlib Tags: ANNUAL CLINICAL UPDATES IN HEMATOLOGICAL MALIGNANCIES Source Type: research