MELAS综合征和Leigh病患者临床对比

目的对比研究和总结线粒体脑肌病伴乳酸血症和脑卒中样发作(mitochondrial encephalomyopathywith lactic acidosis and stroke-like episodes,MELAS)综合征和Leigh病患者的临床、影像学以及病理学特点。方法对10例MELAS综合征、7例Leigh病和1例MELAS综合征-Leigh病叠加患者的临床、影像学及组织病理学特点进行系统分析。结果 10例MELAS综合征患者主要临床表现为运动不耐受、发作性头痛和脑卒中样发作,脑CT及MRI检查结果示病灶多位于枕、顶、颞叶皮质及皮质下,光镜下观察肌肉组织可见不整红边纤维(ragged red fiber,RRF),抗线粒体抗体(anti-mitochondrial antibody,AMA)免疫组化染色可见大量破碎样棕褐色肌纤维(ragged brown fibers,RBFs),3例MELAS综合征患者行脑活检可见棕色AMA阳性的小血管及神经细胞。7例Leigh病患者主要临床表现为眼外肌麻痹、视力下降、肌阵挛样发作及智力发育迟缓,头颅MRI检查结果示双侧底节区、脑干异常信号,肌肉活检未见RRF。4例MELAS综合征、4例Leigh病患者以及1例MELAS综合征-Leigh病叠加患者行MRS检查结果示病变区乳酸水平明显增高。结论 MELAS综合征和Leigh病的临床及影像学特点相比存在明显差别,前者脑部病灶以脑叶皮质及皮质下受累为主,同时表现为脑和肌肉受累症状,肌肉活检可发现RRF;Leigh病患者主要表现为脑干、基底节及视神经受累表现,肌肉活检未见RRF。     

MELAS型线粒体脑肌病的MRI诊断价值

目的探讨MRI对MELAS型线粒体脑肌病的诊断价值。方法6例经临床诊断的MELAS型线粒体脑肌病行T1WI、T2WI、FLAIR、DWI检查。结果MRI显示病变范围广泛,多位于单侧或双侧的顶、枕、颞叶脑回皮质、皮质下白质的多发缺血样病灶,不按动脉供血区分布,还可见与年龄不相符的脑萎缩。结论MRI能显示MELAS型线粒体脑肌病的脑内病变部位、形态和范围,对临床诊断和治疗有重要价值。     

线粒体基因T13094C突变致伴颈髓病变的线粒体脑肌病伴高乳酸血症和卒中样发作/Leigh叠加综合征的临床、影像、病理及基因突变特点(附1例报告)

目的探讨线粒体基因T13094C突变致伴有颈髓病变的线粒体脑肌病伴高乳酸血症和卒中样发作(MELAS)/Leigh叠加综合征的临床、影像、病理及基因突变特点。方法回顾性分析1例伴颈髓病变的MELAS/Leigh叠加综合征患者的临床资料。结果患者为14岁女性,以双下肢麻木、抽搐起病,症状反复发作并进展,逐渐出现呕吐、眼球运动障碍、共济失调、乳酸酸中毒、易激惹、呼吸衰竭、昏迷等,于发病后20个月时死于癫痫持续状态。影像学表现为双侧大脑半球、C_(2-6)段颈髓、丘脑、双侧小脑半球、中脑、脑桥、延髓等处不断变化的新病灶。肌肉病理学检查示Gomori染色可见破碎红纤维,琥珀酸脱氢酶染色可见周边深染的肌纤维,电镜示明显的线粒体数量和形态异常。血和肌肉线粒体基因测序示T13094C杂合突变。结论线粒体基因T13094G突变致MELAS/Leigh综合征出现颈髓病变为线粒体病所罕见;持续进展乃至死亡的病程不同于A3243G突变患者。     

MELAS型线粒体脑肌病的MRI诊断

目的探讨合并乳酸血症和卒中样发作的线粒体脑肌病（MELAS）的磁共振成像（MRI）影像学特点。方法收集经临床病理证实的MELAS型线粒体脑肌病共6例,回顾性分析其MRI和磁共振波谱（MRS）资料。结果脑MRI检查,MELAS表现为大脑半球各叶大小不等片状病灶;病变位于脑皮质区,病灶的分布与脑血供分布不一致;自旋回波T1加权像呈低信号、T2加权像呈高信号;扩散加权成像（DWI）呈高信号。MRS分析显示病灶区见典型的乳酸盐峰,N-乙酰天门冬氨酸盐,肌酸值正常或略降低。扩散张量成像（DTI）显示病灶区脑皮质下白质纤维束破坏、中断、稀少。结论MELAS型线粒体脑肌病的病变形态、分布具有特征性,常规MRI与DWI、DTI及MRS等磁共振技术,对MELAS的定性诊断具有很高的价值。     

MELAS型线粒体脑肌病的脑部MRI表现(附三例报道)

目的 总结分析MELAs型线粒体脑肌病的脑部MRI表现.方法 回顾性分析3例MELAS型线粒体脑肌病患者的临床资料和MRI表现.结果 MRI显示MELAS型线粒体脑肌病表现为以颞叶、顶、枕叶为主的皮层及皮层下白质病变,病变多呈双侧非对称性分布,部分患者以累及基底节为主要表现,T2WI和液体衰减翻转恢复序列对病变的显示有独特的作用,DWI、ADC图及增强扫描能够诊断及鉴别诊断线粒体脑肌病及卒中,MRS对其诊断可以起到辅助作用.结论 MELAS型线粒体脑肌病在MRI图像上具有特征性,MRI影像表现结合临床资料对本病多能作出正确的诊断.     

ND3基因突变导致的线粒体脑肌病重叠综合征二例

目的孤立的线粒体电子传递链复合物Ⅰ缺陷是线粒体病常见的原因之一,可导致几种独特的临床综合征。方法本文报道2例NADH脱氢酶(ND)基因突变导致的线粒体脑肌病的临床资料,分析该2例线粒体脑肌病患者的临床表现,头颅影像学,血乳酸,血生化,血氨基酸,尿有机酸等,脑电图(EEG),肌电图(EMG)和神经传导速度,以及线粒体全基因二代测序和线粒体相关核基因的检查。结果例1患者部分症状符合线粒体脑肌病伴乳酸血症和卒中样发作(MELAS),部分症状符合伴破碎红纤维肌阵挛癫痫(MERRF)。该患者头颅MRI除MELAS常见的皮质病变外,还可见中脑和四叠体对称性异常信号,符合Leigh综合征(LS)影像学表现。线粒体基因二代测序发现MT ND3,10158TC突变。例2患者临床表现完全符合MELAS的临床特征,但头颅MRI可见中脑红核双侧对称性病变,又符合LS的影像学特征。线粒体全基因二代测序发现ND3,10191TC突变。结论对于难以解释的神经系统症状和体征,尤其有多系统受累表现,即使临床表现不符合某种独特的线粒体病综合征,也要提高警惕,避免漏诊。     

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。     

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。     

线粒体DNA G13513A突变所致线粒体脑肌病伴高乳酸血症和脑卒中样发作/Leigh重叠综合征

目的 报道1例线粒体DNA G13513A点突变所致线粒体脑肌病伴高乳酸血症和脑卒中样发作(MELAS)/Leigh重叠综合征的临床、影像学、神经病理学改变特点.方法 患者为22岁女性,反复出现头痛、视力下降和肢体抽动11年,因癫疴持续状态而死亡.之前多次MRI检查发现大脑皮质大片长T1长T2异常信号,病灶从枕叶开始,逐渐波及顶叶,疾病后期累及双侧基底节区及脑干灰质核团.对患者进行脑局部尸体解剖检查,取肌肉标本进行线粒体基因检查.结果 各个脑叶皮质以及双侧纹状体和中脑四叠体可见多灶性层样分布的海绵样改变,出现胶质增生、毛细血管内皮细胞增生以及较多单核细胞反应,其中双侧枕叶和顶叶的皮质全层以及皮质下白质被严重累及.基因检查显示线粒体还原型烟酰胺腺嘌呤二核苷酸脱氢酶5基因存在G13513A点突变.结论 MELAS/Leigh重叠综合征的临床表现以皮质损害为主,影像学改变提示病变先累及大脑皮质,而后累及脑干和基底节区,出现海绵样改变伴随毛细血管增生.     

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。     

MELAS型线粒体脑肌病的临床、影像学和肌肉病理分析

目的 探讨MELAS型线粒体脑肌病的临床表现、影像学特点和肌肉组织病理学改变,提高人们对本病的认识.方法 回顾性分析5例MELAS型线粒体脑肌病的临床表现、脑影像学改变(MRI和CT),以及骨骼肌活检的组织病理学特点.结果 MELAS型线粒体脑肌病的主要临床表现为局灶性或全身性癫NFDCC发作、听觉和视觉障碍、运动不能耐受、认知功能障碍、脑卒中样发作、血乳酸水平升高等.脑影像学检查可见病灶多位于颞、枕、顶叶皮层脑回处,脑MRI表现为长T1、长T2信号,部分患者头颅CT可见基底节钙化.骨骼肌活检5例患者肌肉组织中均可见破碎红边纤维(RRF),2例行电镜检查均可见异常线粒体聚集.结论 MELAS型线粒体脑肌病是一种以高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,容易造成误诊,其诊断需在临床表现和影像学特点的基础上,结合骨骼肌活检病理检查发现RRF或异常线粒体聚集,可获得临床确诊.     

Phenotypic patterns of MELAS/LS overlap syndrome associated with m.13513G>A mutation,and neuropathological findings in one autopsy case

The 13513G>A mutation in the ND5 gene of mitochondrial DNA (mtDNA) is usually associated with mitochondrial encephalomyopathy with lactate acidosis and stroke‐like episodes (MELAS), or Leigh syndrome (LS). In this study, we describe three young Chinese patients with MELAS/LS overlap syndrome who carried the m.13513G>A mutation. Clinical and MRI features were characteristic of both MELAS and LS. Interestingly, the clinical presentation of this overlap syndrome could be variable depending on the degree of relative contribution of MELAS and LS, that is, MELAS as the initial presenting syndrome, LS as the predominant syndrome, or both MELAS and LS appearing at the same time. The final brain MRI showed findings characteristic of both MELAS and LS, with asymmetrical lesions in the cortex and subcortical white matter of the occipital, temporal, and frontal lobes (MELAS), and bilateral and symmetrical lesions in the basal ganglia and brainstem (LS). Brain autopsy in one case revealed infarct‐like lesions in the cerebral cortex, basal ganglia and brainstem, providing further insight into the distribution of the pathological lesions in MELAS/LS overlap syndrome. This is the first report of the brain pathological changes in a patient with m.13513G>A mutation. The spatial distribution of infarct‐like lesions in the brain could explain the symptoms in MELAS/LS overlap syndrome.     

Clinical features of A3243G mitochondrial tRNA mutation

Mitochondrial cytopathy is a heterogeneous group of disorders with a wide range of clinical features. To evaluate the incidence and clinical heterogeneity of A3243G mitochondrial tRNA mutation in the Korean population, we evaluated patients who were clinically suggestive of having mitochondrial encephalomyopathy. Eighty-five patients were included in this study. All showed clinical features of mitochondrial encephalomyopathy and had three or more of the following clinical manifestations: (1) psychomotor regression, (2) hyperlacticacidemia, (3) recurrent stoke-like episodes, (4) idiopathic cardiomyopathy, (5) sensoryneural hearing loss, (6) diabetes mellitus, (7) myopathy, (8) renal disease and (9) relatives with known mitochondrial disease. The patients were clinically classified as MELAS, MERRF, Leigh syndrome, Kearns-Sayre syndrome, chronic progressive external ophthalmoplegia and uncertain. Of the 85 patients, 19 had the A3243G mutation (22.3%). Thirty-one patients showed typical clinical characteristics of MELAS. Fourteen of those 31 patients had A3243G mutation (45.1%). Four patients harboring A3243G mutations showed atypical and heterogeneous clinical features, unlike MELAS. This study revealed the frequent occurrence of A3243G mutation in Korean patients with mitochondrial disorders and their clinical features can be heterogeneous. It will be helpful to screen the presence of A3243G mutation for the genetic diagnosis of mitochondrial encephalomyopathy in Korea.     

线粒体脑肌病伴高乳酸血症和卒中样发作综合征的影像学特征及动态演变

目的探讨线粒体脑肌病伴高乳酸血症和卒中样发作(MELAS)综合征的影像学特点及其动态演变过程。方法收集2011年1月-2016年2月我院经肌肉病理确诊的21例MELAS综合征的资料,对他们的头部CT、MRI、增强MRI、MRA和MRS表现进行回顾性分析。结果 19例患者行头部CT,其中8例显示双侧基底节区对称性钙化。卒中样发作急性期头部磁共振主要表现为T_1WI低信号、T_2WI和FLAIR高信号,DWI高信号或等信号,ADC高信号或低信号;增强MRI未见明显强化或线状强化,MRA未见明显异常,MRS可见N-乙酰天门冬氨酸峰(NAA)下降、乳酸峰(Lac)明显升高。19例(90.5%)病灶累及2个及2个以上脑叶,最常累及的部位是枕叶、颞叶和顶叶。病灶呈层状坏死,分布不符合脑血管的支配区域,动态观察具有"可逆性"、"游走性"和"进展性"。结论 MELAS综合征临床表现复杂,神经影像学具有一定的特征性,具有重要诊断价值。充分认识这些特征,有助于早期诊治、减少误诊。     

Leigh syndrome with spinal cord involvement due to a hemizygous NDUFA1 mutation

Leigh syndrome, which is a common phenotype of pediatric mitochondrial disease, is a progressive neurodegenerative disease. The typical neuroimaging findings of Leigh syndrome include bilateral symmetric lesions in the basal ganglia and/or the brainstem. However, there are a few reports on spinal cord involvement in patients with Leigh syndrome. In the present case, magnetic resonance imaging (MRI) obtained during infancy revealed symmetric lesions in the substantia nigra of a patient with Leigh syndrome with an NDUFA1 mutation; lesions of the bilateral putamen and brainstem were subsequently observed. Additionally, our patient presented large and extended spinal cord lesions. Therefore, this case is suggesting that we should consider the occurrence of spinal cord lesions as an atypical finding in Leigh syndrome.     

线粒体基因G13513A突变导致的线粒体脑肌病六例临床表型分析

目的 报告6例mtDNA G13513A点突变引起的线粒体脑肌病患者的临床、影像学特点,总结mtDNA G13513A突变所致的线粒体病的临床表型.方法 对35例mtDNA常见突变(包括大片段缺失及A3243G、T3271C、A8344G、T8993G/C点突变)检查为阴性的线粒体脑肌病患者,用线粒体DNA全长测序和(或)聚合酶链反应-限制性片段长度多态法检测mtDNA G13513A点突变,分析阳性患者的临床特点,复习文献报道的mtDNA G13513A所致线粒体病的病例.结果 35例患者中有6例存在mtDNA G13513A突变.该6例患者均出现偏盲、轻偏瘫或偏身感觉障碍等卒中样发作表现,其中3例成人发病者以卒中样发作为主要症状,伴随癫痫、头痛、身材矮小、神经性耳聋等,头颅MRI显示以顶-枕-颢叶受累为主的大片病灶,符合成人型线粒体脑肌病伴高乳酸血症和卒中样发作(MELAS)的临床和影像学特点;3例青少年发病者除卒中样发作外,还有构音障碍、共济失调、眼外肌瘫痪等脑干受累的症状,MRI检查可见枕-颞叶大脑皮质非对称性病灶,以及双侧基底节和脑干的对称性病灶,符合青少年型MELAS-Leigh叠加综合征的临床和影像学特点.肌肉病理检查在5例患者发现不整红边纤维.经复习文献,发现mtDNA G13513A突变患者还存在婴幼儿型Leigh或Leigh样综合征表型.结论 mtDNA G13513A点突变是线粒体脑肌病较常见的致病性突变,主要导致Leigh综合征、MELAS-Leigh叠加综合征或MELAS综合征,其临床表型具有年龄依赖性.

Abstract：

Objective To report 6 Chinese patients with mitochondrial encephalomyopathy caused by mitochondrial DNA(mtDNA)G13513A mutation and discuss the mitochondrial phenotype associated with this mutation based on the data of our patient series as well as the reports by others.Methods Direct sequencing of polymerase chain reaction(PCR)products or PCR-RFLP analysis Was performed to screen mtDNA G13513A mutation in 35 cases with mitoehondrial encephalomyopathy.who carried no mtDNA common mutations(1arge 8eale deletion,A3243G,T3271 C,A8344G,or T8993G/C).The clinical features,MRI changes were retrospectively collected and analyzed.Published studies of all patients with mtDNA G13513A mutation were also reviewed.Results Six patients were identified carrying mtDNA G13513A mutation.All patients presented stroke-like episodes with hemianopsia.hemiparesis or hemiparesthesia.Three adult patients presented clinical and radiological features of adult-onset mitochondrial myopathy,encephalopathy,lactic acidosis,and stroke-like episodes(MELAS),including stroke-like episodes,epilepsy,headache,short stature,sensorineural deafness,multifocal lesions on parietal,occipital and temporal lobes on cranial MRI scans.Three iuvenile.onset patients presented the clinical and brain MRI features of MELAS-Leigh syndrome(LS)overlap syndrome.In addition to the stroke-like episodes,they also showed brain stem lesions with dysarthria,ataxia,and ophthalmopJegia. Brain MRI revealed asymmetrical lesions in the cortex of the oecipital and temporal lobes,as well as symmetrical lesions in the bilateral basal ganglia and brainstem.Muslce biopsy showed ragged redfibem in 5 patients.The infant-onset LS or Leigh-like syndrome with mtDNA G135 13A was described in the English literature.Conclusions mtDNA G13513A mutation is a common pathogenic mutmion for mitochondrial encephalomyopathy,which can result in Leigh syndrome,MELAS-LS overlap syndrome and adult MELAS.The onset of various phenotypes is relatively age-dependent.     

MELAS型线粒体脑肌病的临床、病理及影像学研究

目的：探讨线粒体脑肌病中ELAS型的临床、影像学、组织病理学特点及 诊断方法。方法：对4例MELAS患者的临床、影像学（CT、MRI）及组织商理学特点进行系统分析,观察3例患者的肌活检及2例患者的脑活检结果。结果：患者主要临床表现为运动不耐受、发作性头痛和呕吐,局灶或全身性癫痫,认知障碍,脑卒中样发作,神经性耳聋、肥厚性心肌病、内分泌功能紊乱,乳酸水平升高及身材矮小等,肌电图示肌源性改变,脑CT及MRI示病灶多位于枕、顶、颞叶脑回处、CT可见基底节及小脑钙化,肌肉组织可见不整红边纤维（RRF）和异常线粒体,脑活检灰质呈分层性坏死,小血管弥漫增生、星形胶质细胞增生及钙沉积,符合MELAS型诊断,结论：根据MELAS的临床及影像学特点,并结合肌肉及脑组织活检可对该病进行早期诊断。     

以癫(癎)持续状态起病的线粒体脑肌病合并乳酸血症与脑卒中样发作的临床特征分析

目的:探讨以癫(癎)持续状态起病的线粒体脑肌病合并乳酸血症与脑卒中样发作(MELAS)患者的临床、脑电图、影像学及肌肉病理等特点.方法:对收治并最终确诊为MELAS的6例(年龄13-40岁)病例进行总结、分析其临床与脑电图相关特征.结果:6例患者均以癫(癎)持续状态起病,头颅MRI提示脑实质内异常病灶,发作间期脑电图检查提示相应区域有(癎)样放电,肌肉活检见破碎红纤维(RRF).结论:对青少年及成人起病的难治性或进展性癫(癎),临床诊断应考虑线粒体疾病的可能.MELAS患者由于存在线粒体功能损害与ATP能量供应障碍,其神经细胞更易遭受兴奋性毒性侵害,应尽早选择合适的抗癫(癎)药物干预以阻止癫(癎)持续状态的发生.