1例线粒体过氧化物酶体裂殖缺陷性脑病1型的临床分析

Clinical analysis of a case with EMPF1

目的探讨1例线粒体过氧化物酶体裂殖缺陷性脑病1型(EMPF1)患儿的临床特征及其致病基因突变。方法回顾性分析2023年3月河北中西医结合儿童医院诊治的1例EMPF1患儿的临床资料及基因检测结果。结果男性患儿,5岁6个月,主要临床特征为眼睑下垂、共济失调、不典型癫痫样发作,头颅磁共振正常,视频脑电图提示:发作期快慢波活动增多,发作间期大量癫痫样放电。全外显子家系基因检测提示患儿DNM1L基因存在c.335A>G位点的杂合错义变异,经Sanger验证结果显示,其父亲该位点杂合变异;经生物信息学分析推测该变异为致病变异。门诊给予抗癫痫药物治疗无效或加重,目前给予线粒体鸡尾酒疗法治疗中。结论EMPF1主要的临床表现与DNM1L基因突变位点密切相关,综合临床表型及基因检测结果可实现对该病的早诊断;目前c.335A>G突变位点国内外均未见报道,丰富了DNM1L的突变基因谱。

Objective To investigate the clinical characteristics and pathogenic gene mutations of a case with EMPF1.Methods The clinical data and genetic testing results of a child with(encephalopathy due to defective mitochondrial peroxisomal fission-1,EMPF1)admitted to the Hebei Children's Hospital of Integrated Traditional Chinese and Western Medicine in March 2023,were retrospectively analyzed.Results The 5-year-old boy exhibited the primary clinical features of ptosis,ataxia,and atypical epileptic seizures.His head MRI was normal,and Video Electroencephalography revealed a high frequency of epileptic discharges between seizures,along with increased fast and slow wave activity during seizures.The genetic testing of the entire exon pedigree revealed a heterozygous missense variation at the c.335A A>G locus in the DNM1L gene of the child.The Sanger sequencing results revealed that his father has a heterozygous variation at this locus.Bioinformatics analysis suggests that the mutation is likely to be pathogenic.Outpatient treatment with antiepileptic drugs has been ineffective or has worsened,and the patient is currently undergoing mitochondrial cocktail therapy.Conclusion The primary clinical manifestations of EMPF1 are closely associated with the mutation site of the DNM1L gene.The early diagnosis of EMPF1 can be achieved by combining the clinical phenotype and genetic testing results.Currently,there have been no reports of the c.335A>G mutation site both domestically and internationally.This article can enrich the mutation gene spectrum of DNM1L.