双胎兄弟MELAS综合征的临床特点

Clinical features of mitochondrial encephalomyopathy lactic acidosis and stroke-like episodes syndrome in twin brothers

目的探讨异卵双胎兄弟同患线粒体脑肌病伴乳酸血症与卒中样发作综合征(MELAS)的临床特点。方法回顾分析1对异卵双胞胎兄弟同患MELAS病例的临床表现、实验室检查、脑电图、影像学、基因检测结果及诊疗过程。结果先证者,男,7岁时以间断头痛、呕吐、抽搐起病,既往运动不耐受、易疲劳,伴有身材矮小、皮肤多毛,空腹血乳酸值增高,多次视频脑电图背景活动慢化,头颅磁共振成像示随病情反复发作病灶具有迁徙、易变,mtDNA A3243G点突变率34.7%,确诊MELAS。同期筛查同胞异卵弟弟A3243G突变率30%,但无临床症状,间隔3年后以抽搐起病。结论早期基因检测并筛查家系有助于MELAS的诊断,A3243G突变率高,起病年龄早,临床症状重。

Objective To explore the clinical features of mitochondrial encephalomyopathy lactic acidosis and strokelike episodes （MELAS） syndrome in fraternal twins brothers. Methods The clinical data, the results of laboratory examinations, electroencephalogram （EEG）, imaging, and gene detection, and the process of diagnosis and treatment were retrospectively analyzed the fraternal twin brothers with MELAS syndrome. Results The proband, a 7-year-old male, had intermittent headaches, vomit and twitching at onset. He suffered from exercise intolerance, fatigue, accompanied by short stature and hairy, The fasting blood lactic acid level was increased. Multiple video EEG showed the slowdown of background activity. Head MRI showed recurrent lesions with the characteristics of migration and variation. The point mutation rate of mtDNA A3243G was 34.7%. The diagnosis of MELAS was confirmed. At the same time, his fraternal twin brother was screened and found that his point mutation rate of A3243G was 30.0%. Although there was no clinical symptom at that time, he was onset with convulsion after 3 years. Conclusions Gene detection and family screening are helpful for the early diagnosis of MELAS. The mutation rate of A3243G is very high, which can cause an early onset and serious clinical symptoms.