Ca bệnh: Tăng bạch cầu ái toan do tăng sinh tủy ác tính với sắp xếp lại gen PDGFRB ở bệnh nhi dưới 2 tuổi tại Bệnh viện Nhi Trung ương

Hypereosinophilia (HE) has generally been defined as a peripheral blood eosinophil count greater than 1.5 x109 /L. But severe HE is uncommon and relatively rare in children especially under 2 year old and efficacy of imanitib on peaditric patient remain unclear. First time a case with rearrangement PDGFRB was found at National Children’s Hospital. A boy from 15 months old to 23 motnhs old complained abdominal pain and fatigue, no fever. He manifested the expansion of an eosinophil clone combined to aenemia; enlarge spleen caused initial confused diagnostic. His absolute eosinophilia count level from 11.470/ μL (White blood cell 37x 109/L, eosinophil 31%) to 54.984/ μL (White blood cell 174x 109/L, eosinophil 31,6%). Many test were performed to exclude of secondary HE and to diagnosis primary HE. Lastly we decided to make FISH technique with genes: PDGFRB, PDGFRA and FGFR1. It showed 95% rearrangement PDGFRB after 8 months from first on admission. Imatinib is the first choice but it only shows a good response in adult. Although myeloid neoplasm with eosinophilia and PGDFRB rearrangement usually occurs in adults but it can be found on children under 2 year old. The therapeutic benefit of Imatinib in this pediatric patient was consistent with its reported effects in adult patients.