以进行性听力下降为首发症状的线粒体脑肌病伴高乳酸血症和卒中样发作1例报道

目的 探讨以进行性听力下降为首发症状的线粒体脑肌病伴高乳酸血症和卒中样发作综合征(Mitochondrial encephalomyopathy with lactic acidosis and stroke-like episodes,MELAS)的发病特点及其可能的机制,以提高临床医师对MELAS的认识,并进行早期诊断及治疗。方法 分析1例以进行性听力下降为首发症状的MELAS患者的临床资料,并复习相关文献。结果 患者,21岁,女性,以进行性听力下降起病,之后出现反复头痛、癫痫发作及脑卒中样发作,颅脑MRI显示右侧颞顶叶异常信号,MRS显示高乳酸双峰,线粒体相关基因检测显示m.A3243G异质性突变,最终明确诊断为MELAS。结论 MELAS早期症状不典型,对于一些不明原因的听力下降者应当高度警惕该病,尽早完善相关检查以明确诊断。     

线粒体脑肌病伴高乳酸血症和卒中样发作三例

目的分析3例线粒体脑肌病伴高乳酸血症和卒中样发作(MELAS)患者的临床表现影像学特点并探讨其发病机制。方法对3例MELAS患者的临床资料进行分析。结果 3例患者均以卒中样发作为主要表现,伴有内分泌、循环系统等多系统症状。患者头颅影像学有异常表现,肌肉活检示破碎红纤维。结论MELAS的初步诊断主要依据临床表现和影像学特点,肌肉活检可以为进一步明确诊断提供重要的依据。     

以乳酸血症和脑卒中样发作为主要临床表现的线粒体脑肌病

目的：报告线粒体脑肌病伴高乳酸血症和腩卒中样发作（MELAS）病1例,进行相关文献复习并探讨其临床表现、影像学和组织病理学特征。方法：对线粒体脑肌病MELAS患者的临床表现、影像学、组织病理学、免疫组化结果、辅助检查等情况进行分析,同时参考国内外文献对该病的报道。结果：MELAS的主要临床表现为发作性头痛和呕吐、全身性癫痫、精神障碍、脑卒中样发作、血乳酸增高;肌电图示神经源性改变;脑MRI示病灶多位于顶、枕、颞脑回处;肌肉活检见破碎样红纤维和异常线粒体,符合线粒体脑肌病MELAS的特征。结论：线粒体脑肌病MELAS的诊断主要根据临床表现和影像学特点,肌肉活检可确诊。     

伴消化系统症状的成年型线粒体脑肌病伴乳酸血症和卒中样发作一例

线粒体脑肌病伴乳酸血症和卒中样发作(MELAS)是线粒体脑肌病中最为常见的临床类型,是以乳酸血症和卒中样发作为特征的脑和肌肉能量代谢障碍综合征.患者临床表现复杂多样,易被误诊为脑炎、脑梗死、癫痢、多发性肌炎、重症肌无力等疾病.笔者报告l例首诊被误诊为"脑梗死",后经肌肉组织活检和基因检测等证实为MELAS型线粒体脑肌病的病例,并结合文献对该病进行分析及讨论.     

线粒体脑肌病伴高乳酸血症和卒中样发作综合征的临床特点(附1例报告)

目的分析典型线粒体脑肌病伴高乳酸血症和卒中样发作(MELAS)综合征的临床特点。方法回顾性分析1例典型MELAS综合征的临床资料。结果本例患者以言语混乱、行为异常等卒中样症状发病,有母系家族史,病程中有头痛及癫痫样发作。入院查体示听力下降,视野缺损,肌力下降。头颅CT及MRI提示卒中样病灶,且病灶不按血管走行分布。血及CSF检查排除病毒性、自身免疫性脑炎,最终经基因检测分析(mt DNA的A3243G位点AG突变)明确诊断为MELAS综合征。结论 MELAS综合征临床表现主要包括卒中样发作、癫痫、头痛、痴呆、听力损伤、周围神经病变、肌病、乳酸血症、糖尿病等,影像学表现主要包括卒中样病灶、基底节钙化及脑萎缩。     

MELAS综合征的临床及基因诊断研究

<正>线粒体脑肌病伴高乳酸血症及卒中样发作(MELAS)是由线粒体结构或功能缺陷导致的以神经肌肉系统病变为主的多系统疾病,是一种母系遗传病[1]。1984年Pavlakis等[2]报道了首例MELAS综合征患者,该患者以脑卒中样发作和高乳酸血症为主要特点。研究发现其热点突变为mtDNAA3243G突变[3]。本研究报道5例MELAS患者的     

乳酸血症和脑卒中样发作为主要临床表现的线粒体脑肌病(附1例报道)

目的报道线粒体脑肌病伴高乳酸血症和脑卒中样发作(MELAS)病1例,进行相关文献复习,探讨其临床表现、生化、影像学和组织病理学检查在该疾病诊断中作用。方法对线粒体脑肌病伴高乳酸血症和脑卒中样发作(MELAS)患者的临床表现、辅助检查、影像学、组织病理学、免疫组化等情况进行分析。结果 MELAS患者的主要临床表现为发作性头痛、脑卒中样发作、高乳酸血症;脑MRI示病灶位于顶叶、枕叶、颞叶脑回处;肌肉活检见肌纤维变性、破碎样改变以及异常线粒体。结论血乳酸、影像学及肌肉活检在诊断MELAS时有重要的诊断价值,但都缺乏特异表现,需要结合临床和各种检查结果而确诊。     

线粒体脑肌病伴高乳酸血症和卒中样发作综合征:1例报告及文献复习

目的:提高临床对线粒体脑肌病伴高乳酸血症和卒中样发作(mitochondrial myopathy,encephalopathy,lactic acidosis,and stroke-like episode,MELAS)综合征的认识。方法:报道1例MELAS综合征患者的临床表现和诊疗经过,并结合文献复习对MELAS综合征的发病机制、临床表现、诊断和治疗进行探讨。结果:MELAS综合征是线粒体疾病的一种类型,主要累及脑和肌肉组织并伴有卒中样发作,在临床上应与脑炎和脑梗死进行鉴别。早期诊断和治疗有助于阻止病情的进一步发展。结论:MELAS综合征的临床表现复杂多样,远期预后较差,死亡率较高,因此早期诊断和治疗对于改善患者的预后和生活质量均具有重要的临床意义。     

家族性线粒体脑肌病并乳酸血症与卒中样发作的临床特点

正线粒体病是一组由于线粒体结构功能异常所导致的脑和肌肉受累为主的多系统遗传代谢性疾病。线粒体脑肌病伴高乳酸血症和卒中样发作(MELAS)是最常见的类型,其中80%MELAS患者的致病基因和mt DNA A3243G点突变有关~([1])。本文报道一对MELAS母女,对比两者临床特点结合文献,旨在对该病的临床与分子遗传学特征进一步认识。     

线粒体脑肌病伴有高乳酸血症和卒中样发作综合征的临床及基因突变分析

目的 探讨线粒体脑肌病伴有高乳酸血症和卒中样发作综合征(MELAS)的临床及基因突变特征. 方法 对1例MELAS患者的临床表现、影像学、肌肉病理特点进行分析,并用PCR-RFLP结合基因测序方法进行线粒体基因突变分析. 结果 患者主要临床表现为发作性头痛和呕吐、反复卒中样发作、癫痫、运动不耐受、身材矮小、神经性耳聋、乳酸水平升高等.脑CT见双侧基底节多个钙化灶,MRI见枕叶异常信号,1H-MRS见T2WI异常信号区域有明显的乳酸峰,在T2正常信号区域也有小的乳酸峰.光镜及电镜肌肉病理检查未见明显的线粒体异常,基因检测显示mtDNA A3243G杂合突变. 结论 MELAS的诊断必须结合临床表现、影像学、病理学和基因突变检测等结果进行综合分析,病理学检查阴性不能否定MELAS的诊断,诊断MELAS应常规进行mtDNA突变分析.     

MELAS--mitochondrial encephalomyopathy with lactic acidosis and stroke-like episodes syndrome--two cases confirmed by biochemical and molecular investigations. Differential diagnosis of stroke causes

Mitochondrial encephalomyopathy, lactic acidosis and stroke-like episodes syndrome (MELAS) is a maternally inherited multisystem disease caused by mutations of the mitochondrial DNA. The characteristic clinical features are: encephalopathy manifesting as dementia and seizures, stroke-like episodes at young age (usually < 40), lactic acidosis and myopathy with ragged-red fibres. Other frequent manifestations include: sensorineural deafness, diabetes, hypoparathyroidism, peripheral neuropathy and cardiomyopathy. We present two patients with MELAS who were diagnosed 4 and 9 years respectively following the onset of the disease despite the characteristic clinical pictures. The differential diagnostics of inborn and acquired disorders causing stroke is included. We regard that mitochondrial diseases are still insufficiently known and are frequently misdiagnosed. The knowledge is indispensable for establishing diagnosis and accurate genetic counselling. Although there is no specific therapy for mitochondrial diseases to date, coenzyme Q and various vitamins as well as moderate degree exercise might be recommended.     

MELAS with prominent white matter gliosis and atrophy of the cerebellar granular layer: a clinical, genetic, and pathological study

This report concerns an autopsy case of mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episodes (MELAS) with unusual neuropathological findings. The patient was a Japanese woman who was 21 years old at the time of death. Her mother is a patient with genetically confirmed MELAS. Her clinical manifestations included convulsions and lactic acidosis in the latter half of the first decade of life, followed by deafness, dementia, muscle weakness in the lower extremities, slight ataxia in the upper and lower extremities, and diabetes mellitus. Muscle biopsy revealed ragged-red fibers, and genetic study showed a point mutation at nucleotide pair 3243 in mitochondrial DNA. She died of lactic acidosis. In the clinical course, she did not develop stroke-like episodes. The neuropathological examination revealed not only minute to small necrotic foci in the cerebral cortex, amygdala, hippocampus, and cerebellum, but also prominent white matter gliosis in the central nervous system and cerebellar cortical degeneration of granular cell type. Our neuropathological findings, including prominent white matter gliosis of the central nervous system and cerebellar cortical degeneration of granular cell type, may indicate morphologically widespread cellular dysfunction, not restricted to either neuronal or vascular derangement, in the brain pathology of MELAS. Received: 28 July 1998 / Revised, accepted: 27 October 1998     

线粒体脑肌病伴高乳酸血症及卒中样发作的发病机制及临床研究进展

线粒体脯肌病伴高乳酸血症及脑卒中样发作（MELAS）是在1984年前首次被提出的,该病主要是由线粒体基因组第3243号位点的腺嘌呤突变为鸟嘌呤（m．3243A〉G）所导致。MELAS主要的神经系统表现为抽搐、脑卒中样发作和脑病,还包括一些其他症状如身材矮小、认知功能障碍、偏头痛、痴呆、心肌病、心脏传导阻滞和糖尿病等。本文主要从分子生物学角度讨论MELAS病的病因、诊断方式以及治疗手段的研究进展,着重阐述了细胞色素C氧化酶（COX）失调假说在MELAS病的发病机制中的作用。虽然MELAS病的治疗方法仍然有限,但是现有的和潜在的治疗方式值得探讨。     

CPEO and carnitine deficiency overlapping in MELAS syndrome

Mitochondrial myopathy, encephalopathy with lactic acidosis and stroke-like episodes (MELAS) syndrome is one of the mitochondrial encephalomyopathies that has distinct clinical features including stroke-like episodes with migraine-like headache, nausea, vomiting, encephalopathy and lactic acidosis. We report a 27-year-old woman who presented with partial seizure, stroke-like episodes including hemiparesis, hemianopia and hemihypethesia, sensorineural hearing loss, migraine-like headache, and lactic acidosis. Brain computed tomographic scan showed encephalomalacia in the right parieto-occipital area and recent hypodensity in the left temporoparieto-occipital area with cortical atrophy. Muscle biopsy revealed ragged-red fibers and paracrystaline inclusions in the mitochondria. Genetic study revealed an A to G point mutation at nucleotide position (np) 3243 of mitochondrial DNA. External ophthalmoplegia and ptosis were also found during two exaggerated episodes in this patient. Therefore, the overlapping syndrome of chronic progressive external ophthalmoplegia in the MELAS syndrome is considered in this case. Furthermore, we also found carnitine deficiency in this patient and she was responsive well to steroid therapy. Muscle biopsy also revealed excessive lipid droplets deposits. Therefore, the carnitine defiency may occur in MELAS syndrome with the A to G point mutation at np 3243. We recommend the steroid or carnitine supplement therapy be applied to the MELAS syndrome with carnitine deficiency.     

MELAS综合征八例

目的探讨MELAS综合征(线粒体脑肌病伴乳酸血症和卒中样发作)的临床特征,为早期诊断和治疗提供参考。方法对8例确诊的MELAS综合征患者的临床表现、肌活检病理及影像学资料进行回顾性分析。结果头痛、抽搐、运动耐受差、智能障碍、脑卒中样发作、血乳酸水平升高为本组患者的主要临床表现。8例患者脑内病灶均表现为T1WI低信号、T2WI高信号,病变主要累及额、颞、顶、枕叶皮层、皮层下及基底节,伴有不同程度的脑萎缩,病灶多发且与血管分布区不一致。8例患者行肌肉活检可见破碎红纤维(RRF)、异常线粒体增多。结论 MELAS综合征临床表现复杂多样,确诊依赖于临床特征分析和肌肉活检。磁共振成像在线粒体脑肌病的诊断、鉴别诊断方面具有一定的价值。     

线粒体脑肌病伴高乳酸血症和卒中样发作的诊断

目的 分析总结线粒体脑肌病伴高乳酸血症和卒中样发作(MELAS)的临床表现和辅助检查结果,探讨在MELAS诊断中存在的问题,提出MELAS早期临床诊断的可行性.方法 归纳总结34例MELAS患者的临床表现,寻找对MELAS患者相对特异的症状组合.同时总结分析各项辅助检查结果,结合文献复习解读血和脑脊液的乳酸水平、神经影像、肌肉活体组织检查(活检)和基因检查对于MELAS诊断的意义和局限性.结果 本组患者最常见的临床表现依次为:癫癎发作、头痛、智能下降、卒中样发作、发育异常、四肢无力和易疲劳、眼肌麻痹.血空腹乳酸或运动后乳酸升高23例(67.6%).32例头颅MRI异常的患者最常见的受累部位依次为枕叶、顶叶、颞叶、基底节、额叶、小脑和深部白质.32例患者行肌肉活检,有阳性发现的共24例(75%),阴性的8例(25%).14例患者行基因检查,9例发现A3243G位点突变,5例未发现该位点突变.结论 认识MELAS的各种临床表现,争取在卒中样发作出现前早期诊断是完全可行的.     

A cluster of disseminated small cortical lesions in MELAS: its distinctive clinical and neuroimaging features

Journal of Neurology - To investigate a diversity of stroke-like episodes (SLEs) in mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes (MELAS), and report a disseminated...     

Beneficial effect of L-arginine for stroke-like episode in MELAS

We here reported the clinical course and therapeutic details of a 16-year-old girl with mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episodes (MELAS) who had had five stroke-like episodes (two episodes were clinically mild, while the three subsequent episodes were severe). Among the three episodes, the symptoms improved earliest and magnetic resonance spectroscopy abnormality was minimal when given L-arginine in addition to prednisolone, glycerol and edalavone. L-arginine administration during the acute phase of MELAS might be a potential therapy to reduce brain damage due to mitochondrial dysfunction.