遗传性球型红细胞增多症的临床分析

Clinical analysis of hereditary spherocytosis

目的探讨遗传性球型红细胞增多症(HS)的临床特点及相关基因突变。方法选择2017年1月1日至2019年7月31日,于昆明市儿童医院门诊及住院诊断为HS的10例患儿为研究对象。其中,女性患儿为3例,男性为7例,平均年龄为4.5岁。收集这10例HS患儿一般临床资料,采用高通量测序技术对其进行HS相关基因突变检测。回顾性分析HS患儿的临床特征、相关基因突变及疗效。本研究遵循的程序符合2013年修订版《世界医学协会赫尔辛基宣言》的要求。结果①本研究10例患儿均以贫血、黄疸、脾大为临床表现。贫血以小细胞性贫血为主,重度贫血为4例,中度贫血为4例,轻度贫血为2例。患儿脾大以轻、中度为主,轻度脾大为4例,中度脾大为6例,无一例为重度脾大。患儿输血次数不一。3例患儿外周血球形红细胞比例增多,其余7例正常。4例红细胞渗透脆性增加,其余6例正常。患儿地中海贫血基因、铁蛋白及红细胞葡萄糖-6-磷酸脱氢酶(G-6-PD)水平均正常。②高通量基因测序结果显示,10例患儿中,6例存在ANK1、2例存在SPTA1、1例存在SPTB基因突变,1例存在SPTB基因2~3号外显子疑似重复。其中,ANK1基因c.4585C>T(p.R1529X)、c.3877C>T(p.R1293X)突变在人类基因突变数据库(HGMD)专业版中,已有文献报道与球形红细胞增多症相关。ANK1基因c.1471C>T(p.Q491X)、c.1817delT(p.L606Cfs*31)、c.4390+5G>T(IVS36dsG-T+5)、c.4189C>T(p.L1397F)突变,在HGMD专业版中未见报道。根据美国医学遗传学与基因组学学会(ACMG)指南,考虑ANK1基因c.1471C>T(p.Q491X)、c.1817delT(p.L606Cfs*31)突变为新发可疑致病突变。SPTA1基因c.4766G>A(p.W1589X)、c.5432G>A(p.R1811Q)突变,SPTB基因2~3号外显子疑似重复未见文献报道。其中,考虑SPTA1基因c.4766G>A(p.W1589X)突变为新发可疑致病突变。SPTB基因c.4735C>T(p.R1579X)突变已有文献报道。SPTB基因c.797_798del(p.I266Nfs*28)未见文献报道,并且考虑为新发可疑致病突变。③本研究4例接受部分脾动脉栓塞术的患儿中,2例术后未再接受输血治疗;1例术后6个月内,未再接受输血治疗,6个月后每2~3个月接受1次输血治疗,1例失访。其余6例未接受部分脾动脉栓塞术的患儿中,1例每2个月接受输血治疗1次;5例血红蛋白(Hb)值>90 g/L。结论对于临床特征不典型的患者可以采用高通量测序技术辅助诊断HS。本研究发现4个未见文献报道的ANK1及SPTA、SPTB基因突变。

Objective To investigate clinical characteristics and related gene mutations of hereditary spherocytosis(HS).Methods From January 1,2017 and July 31,2019,ten cases of children diagnosed with HS in outpatients and inpatients at Kunming Children′s Hospital were selected as study subjects.Among them,3 cases were female and 7 cases were male,with an average age of 4.5 years.General clinical data of children with HS were collected,and high-throughput sequencing technology was used to detect related gene mutations in the children.Clinical data,related gene mutations and treatment efficacy of HS children were analyzed retrospectively.The procedure of this study is accordance with the requirement of the World Medical Association Declaration of Helsinki revised in 2013.Results①Clinical manifestations of anemia,jaundice and spleen were significant in all 10 cases of HS children.Anemia was mainly small-cell anemia,with 4 cases of severe anemia,4 cases of moderate anemia and 2 cases of mild anemia.Splenomegaly of the children was mainly mild and moderate,with 4 cases of mild splenomegaly,6 cases of moderate splenomegaly,and none of them had severe splenomegaly.Transfusion frequency of the children varied.Among them,the proportion of spherical erythrocytes in peripheral blood increased in 3 cases,7 cases were normal.Four cases were increased in osmotic brittleness,and 6 cases were normal.Thalassemia genes of children were normal.Levels of ferritin and red blood cell glucose-6-phosphate dehydrogenase(G-6-PD)of children were normal.②High throughput gene sequencing results showed,among the 10 children,6 cases had ANK1 gene mutation,2 cases had SPTA1 gene mutation,1 case had SPTB gene mutation,and 1 case had SPTB gene exon 2-3 suspected duplication.Among them,ANK1 gene c.4585C>T(p.R1529X)and c.3877C>T(p.R1293X)mutations were reported to be associated with spherocytosis in Human Gene Mutation Database(HGMD)professional version.ANK1 genes c.1471C>T(p.Q491X),c.1817delT(p.L606Cfs*31),c.4390+5G>T(IVS36dsG-T+5),c.4189C>T(p.L1397F)mutations were not reported in the HGMD professional version.According to American College of Medical Genetics and Genomics(ACMG)guidelines,ANK1 gene c.1471C>T(p.Q491X)and c.1817delT(p.L606Cfs*31)mutations were considered as new suspected pathogenic mutations.SPTA1 gene c.4766G>A(p.W1589X),c.5432G>A(p.R1811Q)mutation,SPTB gene exon 2-3 suspected duplication were not reported in literature.Among them,SPTA1 gene c.4766G>A(p.R1811Q)mutation was considered as a new suspected pathogenic mutation.SPTB gene c.4735C>T(p.R1579X)mutation was reported in the HGMD professional version.SPTB gene c.797_798del(p.I266Nfs*28)mutation was not reported in the literature and was considered to be a new suspected pathogenic mutation.③In this study,among the 4 cases who received splenic artery embolization,2 cases did not receive blood transfusion after surgery.Within 6 months after splenic artery embolization,1 case did not receive blood transfusion.And after 6 months,this case received blood transfusion once every 2-3 months.One child was lost during follow-up.Among the rest 6 children who did not receive splenic artery embolization,1 case received blood transfusion once every 2 months,5 case with hemoglobin(Hb)value over 90 g/L.Conclusions High-throughput sequencing technology can help diagnose HS with atypical clinical features.In this study,4 unreported gene mutations of ANK1,SPTA and SPTB genes were found.