DNA A3243G突变相关MELAS综合征4例临床特点及治疗

Clinical features and literature review of 4 cases of DNA A3243G mutation-related MELAS syndrome

目的探讨DNA A3243G突变相关的线粒体脑肌病伴乳酸血症与卒中样发作综合征(Mitochondrial encephalomyopathy,lactic acidosis,and stroke-like episodes,MELAS)的临床特点及基因学表型,提高临床医生对该病的认识及诊断。方法回顾性分析2017年6月-2018年6月于河南省人民医院小儿神经内科门诊及住院诊治的4例DNA A3243G突变相关MELAS综合征患儿的临床资料及影像学特征,并复习相关文献。结果 4例患儿中3例因抽搐、1例因头晕起病,经基因检测证实均为线粒体DNA A3243G突变引起的MELAS综合征,予以抗癫痫治疗,随访1年,4例患者中2例患儿病情稳定,1例患儿仍有发作,1例患儿病情无好转。结论 DNA A3243G突变相关MELAS综合征患者的临床表型异质性多因DNA突变的"异质性"和"阈效应"所致,DNA A3243G突变率高达80%,在提倡精准医疗的时代,基因检查有助于MELAS综合征的早期确诊和治疗,提高患者的生活质量,改善预后。

Objective To investigate the clinical characteristics and genetic phenotype of mitochondrial myopathy associated with lactic acidemia and stroke-like seizure syndrome(MELAS) in DNA A3243 G mutation, and to improve the clinical understanding and diagnosis. Methods The clinical data and imaging characteristics of 4 patients with DNA A3243 G mutation-related MELAS syndrome who were diagnosed and treated in the Department of Pediatric Neurology, Henan Provincial People’s Hospital from June 2017 to June 2018 were retrospectively reviewed. Results Of the 4 patients, 3 were caused by convulsions, 1 was caused by dizziness, and the MELAS syndrome caused by mitochondrial DNA A3243 G mutation was confirmed by genetic testing. The patients were treated with anti-epilepsy drugs. The patients were followed up for at least 1 year, and 2 of 4 patients were stable, 1 patient still had seizures, and 1 patient did not improved. Conclusions The clinical phenotypic heterogeneity of patients with DNA A3243 G mutationrelated MELAS syndrome is caused by the "heterogeneity" and "threshold effect" of DNA mutation. The mutation rate of DNA A3243 G is as high as 80%. In the era of promoting precision medicine, genes examination can help early diagnosis and early treatment of MELAS syndrome as well as improve the quality of life of patients and improve the prognosis.