Department of Laboratory Medicine, Policlinico Tor Vergata, Rome, Italy.
Br J Haematol. 2010 Dec;151(5):440-6. doi: 10.1111/j.1365-2141.2010.08394.x. Epub 2010 Oct 19.
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.
高嗜酸性粒细胞综合征（HES）包括一组异质性疾病，其特征为血液和骨髓中嗜酸性粒细胞数量持续增加。文献中很少有儿科高嗜酸性粒细胞增多症（pHES）的病例描述。鉴于预后和治疗的意义，早期识别可能向淋巴髓细胞增生性疾病发展的 pHES 很重要。在 presentation 和临床病程中分析了 10 例 pHES 患者的分子特征，包括 BCR-ABL1 和 FIP1L1/PDGFRA 融合基因分析、WT1 基因拷贝数定量以及 T 细胞受体（TCR）和免疫球蛋白重链（IGH）的克隆性。所有患者的核型均正常，TCR 构型均为胚系。5 例患儿在 presentation 时出现 IGH 克隆性：其中 2 例分别在 6 个月和 12 个月时发展为 B 型非霍奇金淋巴瘤和 B 系急性淋巴细胞白血病，2 例在随访期间自发恢复为多克隆 IGH 谱，最后 1 例在 19 个月后仍持续存在 pHES 而无 B 克隆演变。1 例患者存在 PDGFRA/FIP1L1 融合，接受伊马替尼治疗后获得血液学和分子缓解。IGH 重排是 pHES 的常见分子特征，可能先于 B 细胞克隆扩增并发展为儿童 B 细胞恶性肿瘤。
