儿童线粒体脑肌病伴乳酸酸中毒和卒中样发作的临床特征  

Clinical Characteristics of children with syndrome of mitochondrial encephalomyopathy,lactic acidosis and stroke-like episode

作　　者：马秀伟[1] 侯豫[1] 王三梅[1] 辜蕊洁[1] 刘京京[1] 王永霞[1] 封志纯[1] 

机构地区：[1]北京军区总医院附属八一儿童医院神经发育科,北京市100700

出　　处：《中华全科医学》2015年第5期728-730,752,共4页Chinese Journal of General Practice

摘　　要：目的总结儿童线粒体脑肌病伴乳酸酸中毒和卒中样发作（MELAS）的临床、影像学及分子遗传学特征,以提高诊疗水平。方法对7例经基因突变或线粒体呼吸链酶学确诊的MELAS患儿的临床表现及实验室检查、影像学资料、基因突变、酶学特点进行回顾性分析,并对临床转归进行随访。结果所有患儿均有卒中样发作、头痛、呕吐、惊厥。7例患儿均有乳酸升高。头颅MRI均显示T1WI低信号及T2WI高信号,常多个脑叶同时受累,容易受累部位主要为顶叶、颞叶和枕叶,额叶、基底节区、小脑及丘脑亦可受累。陈旧病灶均呈脑萎缩。4例白细胞线粒体DNA有A3243G突变,突变率为29.7%～60%,其中1例母亲存在同样突变。3例行线粒体呼吸链酶学检测,2例显示复合物Ⅰ缺陷,1例显示复合物Ⅰ、Ⅳ缺陷。随访7例,均有不同程度智力损害,并仍需继续服用抗癫痫药物。结论充分认识儿童MELAS的临床、实验室检查、头颅影像、基因突变、呼吸链酶学特点,有助于早期诊断、治疗和遗传咨询。Objective To summarize the characteristics of clinical manifestation,brain image and molecular genetics of children with P the syndrome of mitochondrial encephalomyopathy,lactic acidosis,and strokelike episodes（ MELAS）,and improve the diagnosis and management of MELAS. Methods The clinical manifestation,laboratorial data,brain image,mitochondrial gene mutations,and mitochondrial complex I-V enzyme activity were analyzed in 7 patients with MELAS.Their treatment and prognosis was evaluated by following up. Results The most common clinical presentations were stroke-like episode,seizures,headache and vomiting in the children with MELAS. Serum lactate level increased in all the cases. All patients showed low signal intensity on T1 WI and high signal intensity on T2 WI in brain image. The distribution of lesions was multiple,and the most common lesions were located in the parietal lobe,temporal lobe and occipital lobe.Frontal lobe,basal ganglion,cerebellum and thalamus can also be damaged. Cerebral atrophy was found in the old lesions.The mt DNA gene mutational analysis showed A3243 G mutation in white blood cells of 4 patients,and the mutation rate varied from 29. 7% to 60%. The same mutation was found in one patient＇s mother. Mitochondrial complex Ⅰ enzyme activity was measured in peripheral leukocytes of 3 patients. Isolated complex I deficiency was found in 2 cases,and a combined deficiency of complex I and Ⅳ in one patient. All the patients had some degrees of mental retardation and needed antiepileptic treatment through following up. Conclusion Fully understanding the characteristics of clinical manifestation,laboratory tests,brain image,molecular features,and oxidative phosphorylation enzyme activity assay in children with MELAS can be helpful to the early diagnosis,treatment and genetic consultation.

关 键 词：线粒体脑肌病 临床特点 磁共振成像 突变 

分 类 号：R729[医药卫生—儿科] R742.89[医药卫生—临床医学]