ELANE基因突变致先天性粒细胞减少症1例临床及基因分析

Clinical and genetic analysis of a patient with congenital neutropenia caused by ELANE gene mutation

目的探讨ELANE基因突变所致先天性粒细胞减少症的临床特征、基因诊断、治疗及预后。方法分析1例先天性粒细胞减少症患儿的临床表现、免疫学指标、基因变异特点及诊治经过。结果患儿,女,7个月,生后粒细胞减少伴反复感染6个月;1月龄时患支气管肺炎、中耳炎,2月龄时患化脓性颈部淋巴结炎、脐部化脓性感染、自身免疫性溶血性贫血,疑诊幼年型粒单核细胞白血病。体格检查发现,肝脏肋下4 cm,脾脏肋下1 cm,质韧,余未见异常。中性粒细胞(0.10～1.38)×10~9/L、单核细胞(1. 70～3. 58)×10~9/L、血红蛋白(65～10~8)g/L;多种病原学检测阳性;直接抗人球蛋白实验++++;IgG 24.28 g/L;淋巴细胞分型提示B细胞数量增多。骨髓涂片示原粒细胞占7%,中性中幼粒细胞以下阶段罕见,幼稚单核细胞占4.5%。基因测序显示ELANE基因3号外显子c.278_289del、p.93_97del自发突变。结论 ELANE基因突变致先天性粒细胞减少症临床特征包括难治性反复细菌感染和中性粒细胞减少,可伴自身免疫现象。

ObjectiveTo investigate clinical features, genetic diagnosis, management and prognosis of congenital neutropenia caused by ELANE gene mutation. MethodsClinical manifestations, immunological data, gene mutation, processes of diagnosis and treatment of a patient with congenital neutropenia caused by ELANE gene mutation were retrospectively analyzed. ResultsA 7-month old girl, suffered from neutropenia and recurrent infection for 6 months, presented with bronchial pneumonia and otitis media at 1 month old with suppurative cervical lymphadenitis, umbilical purulent infection, autoimmune hemolytic anemia and suspected juvenile myelomonocytic leukemia. When she was 2 months old, it progressed with obvious hepatomegaly and a slight enlargement of spleen, which lead to persistent neutropenia （0.1×109/L ~1.38×109/L）, monocytosis （1.7×109/L ~3.58×109/L） and low hemoglobin levels （65 ~ 108 g/L）. Multiple etiological culture tests were positive. Direct anti-human globulin test was strongly positive. Other abnormal immunological screens showed elevated levels of IgG （24.28 g/L）, and increased B lymphocytes. Bone marrow smears showed myeloblasts （7%） and promonocyte （4.5%） without any neutral medium promyelocyte, neutral late promyelocyte or neutrophils. A heterozygous c.278_289del （p.93_97del） mutation of ELANE gene was identifed by gene sequencing. ConclusionsThe main clinical features of congenital neutropenia caused by ELANE gene mutation include refractory recurrent bacterial infections, and neutropenia possiblely accompanied by autoimmunity.