Pediatric hypereosinophilia: FIP1L1-PDGFRA myeloproliferative disease in a 14-year-old male

Abstract

Hypereosinophilic myeloproliferative disease is a rare entity in the pediatric population. We report the fifth known pediatric case of FIP1L1-PDFGRA hypereosinophilia. This fusion drives hypereosinophilia, and often neutrophilia, with the propensity for T-cell or myeloid transformation. The exquisite sensitivity of the FIP1L1-PDGFRA fusion to the tyrosine kinase inhibitor Imatinib, abrogates the short-term life threatening complications of hyper-eosinophilia. The issues arising from long-term treatment with Imatinib, including optimal dosing, length of treatment, and bone marrow transplantation, are explored in the accompanying discussion. These issues are particularly relevant in pediatric patients facing life-long therapy.