Molecular characterization of paediatric idiopathic hypereosinophilia.
The hypereosinophilic syndromes (HES) include a group of heterogeneous diseases characterized by the persistent increase of the number of eosinophils in blood and bone marrow. Few cases of paediatric hypereosinophilia (pHES) have been described in the literature. Early identification of pHES that may evolve towards a lymphomyeloproliferative disease is relevant in light of prognostic and therapeutic implications. Molecular features of 10 pHES patients were analysed at presentation and during their clinical course, including analysis of BCR-ABL1 and FIP1L1/PDGFRA fusion genes, quantitation of WT1 gene copy number and clonality of T-cell receptor (TCR) and immunoglobulin heavy chain (IGH). All patients had normal karyotype and germline TCR configuration. Five children showed IGH clonality at presentation: of these, two developed a B non-Hodgkin lymphoma and a B-lineage acute lymphocytic leukaemia at six and 12 months respectively, two spontaneously reverted to a polyclonal IGH profile during the follow-up, and the last one persisted with pHES without B-clonal evolution after 19 months. One patient had a PDGFRA/FIP1L1 fusion and achieved hematologic and molecular remission after imatinib therapy. IGH rearrangement was observed to be a frequent molecular feature of pHES and may precede B-cell clonal expansion and evolution into B-cell malignancies in children.
Department of Laboratory Medicine, Policlinico Tor Vergata, Rome, Italy. cristinarapanotti@yahoo.it
Maria Cristina
MC
Rapanotti
Roberta
R
Caruso
Emanuele
E
Ammatuna
Serena
S
Zaza
Laura
L
Trotta
Mariadomenica
M
Divona
Laura
L
Cicconi
Daria
D
Funaro
Giorgio
G
Federici
Sergio
S
Amadori
Giulio
G
De Rossi
Francesco
F
Lo-Coco
D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D005260:Female; D005500:Follow-Up Studies; D015321:Gene Rearrangement; D006801:Humans; D017681:Hypereosinophilic Syndrome / Q000150:complications / Q000175:diagnosis / Q000235:genetics* / Q000276:immunology; D007143:Immunoglobulin Heavy Chains / Q000235:genetics; D016130:Immunophenotyping; D007223:Infant; D016393:Lymphoma, B-Cell / Q000209:etiology; D008297:Male; D054198:Precursor Cell Lymphoblastic Leukemia-Lymphoma / Q000209:etiology; D011379:Prognosis
D007143:Immunoglobulin Heavy Chains