眼咽肌型肌营养不良一例

眼咽肌型肌营养不良(oculopharyngeal musculardystrophy,OPMD)是一原发于肌肉的遗传性变性疾病,为进行性肌营养不良的一种特殊类型,主要临床特征为缓慢进展的眼外肌和吞咽肌麻痹,临床较少见。此文报道一例经病理确诊的OPMD有关资料。1临床资料患者男,20岁,农民。因双上睑下垂,视物成双5年,吞咽困难、构音障碍、四肢无力3年入院。现病史:15岁时出现双上睑轻度下垂,视物模糊、视物成双影,稍感说话费力;2年后渐出现吞咽困难,复视、言语不清较前加重,同时出现四肢无力,肌肉疼痛,伴有肌肉萎缩。入院查体:神志清楚,构音障碍,双上睑下垂,双眼…     

眼咽型肌营养不良一家系临床、电生理、病理及基因分析

目的 报道1个出现神经源性骨骼肌损害的眼咽型肌营养不良(OPMD)家系的临床、骨骼肌病理和基因改变特点.方法 先证者为60岁男性,50岁时出现双下肢近端无力,53岁出现吞咽困难和构音障碍,57岁出现双眼睑下垂和眼球突出.肌酸激酶轻度增加,四肢肌电图为神经源性损伤,周围神经传导速度下降20%～43%.家系3代中除先证者外尚有5例在45岁后出现吞咽困难,4～20年后出现眼睑下垂,其中3例有肢体无力.对先证者左肱二头肌做肌肉活体组织检查,标本进行组织学、酶组织化学以及免疫组织化学染色(以抗结蛋白和泛素蛋白抗体作为一抗)和超微病理检查.对先证者和家系中另外18人进行多腺苷酸结合蛋白(PABPN1)基因检查.结果 先证者肌纤维内出现镶边空泡伴泛素阳性沉积物和成组分布的小角状萎缩肌纤维,个别肌纤维出现再生改变伴随结蛋白沉积,可见细胞色素C氧化酶阴性肌纤维.电镜检查发现约3%的肌纤维核内存在栅栏样细丝包涵体.先证者和另外11名家系成员的PABPN1基因存在(GCG)9异常扩增.结论 杂合(GCG).异常扩增性OPMD可先出现咽喉肌无力,伴随脱髓鞘性神经病.我国患者也存在肌纤维核内包涵体.     

眼咽型肌营养不良病理及分子遗传学研究

目的研究眼咽肌营养不良(ocu lopharyngeal muscu lar dystrophy,OPMD)的遗传学和病理形态学表现。方法应用透射电镜技术对6例患者提上睑肌进行超微结构观察和分析,并采用聚合酶链反应(PCR)产物直接测序法对来自3个家系的OPMD患者11例及其亲属共27名外周血进行检测。结果4例患者眼肌活检标本于电镜下可观察到特异性核内包涵体(intranuc lear inc lusions,INIs),在细胞核内出现率分别为18%、20%、34%及40%。而9例患者基因中存在(GCG)6重复序列拷贝数异常(GCG)8、(GCG)10,亲属中未发病者均未见重复序列的异常扩增。结论OPMD患者受累眼肌活组织检查于电镜下可见INIs,并且INIs出现比率与异常扩增数目成正比。OPMD患者存在(GCG)6重复序列的异常扩增,并且发病年龄与异常扩增数目成反比。     

眼咽型肌营养不良汉族六家系的临床和遗传学特点

目的 初步总结我国汉族眼咽型肌营养不良(OPMD)患者的临床和多腺苷酸结合蛋白核1(PABPN1)基因改变特点.方法 6个OPMD家系共28例患者,男性13例,女性15例,发病年龄32～70岁,平均发病年龄49.7岁.在可确定首发症状的患者中,以吞咽困难或构音障碍首发的13例、眼睑下垂首发的4例、双下肢无力首发的1例.经过3～20年均出现眼睑下垂、吞咽困难和构音障碍,其中7例出现四肢近端无力.对6例先证者做肌肉活体组织检查,标本进行常规组织病理和电镜检查.对6个家系的先证者以及部分家庭成员进行PABPN1基因检查,并对6例先证者进行单体型分析.结果 6例先证者的肌肉活体组织检查均发现肌纤维直径轻度变异加大伴随肌纤维内镶边空泡形成,4例患者经电镜检查发现OPMD典型的核内栅栏样丝状包涵体.3个家系的PABPN1基因型为(GCG)9,另外3个家系的基因型分别为(GCG)6(GCA)1(GCG)3、(GCG)10和(GCG)8.2个携带(GCG)9突变的家系存在rs2239579(C)-(GCG)9-SNP2622(C)的单倍体型.结论 吞咽异常和眼睑下垂均是我国汉族OPMD患者的首发症状.肌纤维出现镶边空泡以及核内包涵体是我国患者的常见病理改变.PABPN1基因的(GCG)异常扩增和(GCA)插入突变均出现在我国患者,起源具有多源性.携带(GCG)9突变的部分家系可能来自共同祖先.     

眼咽型远端型肌病二家系的临床、病理及分子学特点

目的 探讨2个眼咽型远端型肌病(OPDM)家系的临床、病理及分子生物学特点.方法 对2个家系的先证者行血清肌酶、肌电图、肌肉活体组织检查、肌肉酶组织染色及电镜分析,并于复诊时提取其静脉血DNA样本,进一步行编码多聚腺苷酸结合蛋白核1(PABPN1)、GNE基因突变分析.结果 家系1为同代3兄弟发病,家系2为2代4人发病.起病以发音困难伴双下肢无力居多;以发音及吞咽困难为表现的咽部肌群受累较突出.肌肉超微结构电镜分析未见到眼咽型肌营养不良样核内包涵体,2家系先证者PABPN1基因GCN重复拷贝数均为正常(10次,GCG6GCA3GCG1),且GNE基因2～12号外显子均未发现突变.结论 2个OPDM家系起病年龄、形式与日本患者类似,但肌肉受累方式有所不同.家系1为中国首个常染色体隐性遗传OPDM家系.本研究结果证实OPDM是一个表型、病理、遗传学独立的肌病实体.     

眼咽型肌营养不良症一家系临床及分子生物学特征分析

目的 总结一眼咽型肌营养不良症(OPMD)家系的临床及分子生物学特征.方法 收集云南省楚雄彝族自治州的一OPMD家系的临床资料,并对其中6位家族成员行外周静脉血基因组DNA分离,通过聚合酶链反应(PCR)、TA克隆和Sanger测序,检测PABPN1基因变异特点.结果 该OPMD家系中4位成员均于50岁后发病,以眼睑下...     

临床诊断眼咽远端型肌病1例及文献复习

目的:探讨眼咽远端型肌病(OPDM)的临床表现、肌肉病理和分子遗传学特征.方法:报道1例临床疑似OPDM患者的临床和肌肉病理资料,对患者及其亲属共3名行多聚腺嘌呤结合蛋白核1(pabpnl)基因突变分析,并结合文献报道病例予以比较.结果:患者24岁起病,表现双侧眼外肌麻痹、声音嘶哑.肌肉病理显示个别肌纤维萎缩为主的肌源性损害,pabpnl基因检测无异常GCG重复序列扩增.结论:OPDM起病早,早期仅表现眼外肌及咽喉肌群麻痹,pabpnl基因GCG重复序列无异常扩增.     

强直性肌营养不良Ⅰ型临床、病理、骨骼肌磁共振特点

目的总结11例强直性肌营养不良Ⅰ型(DM1)患者的临床、病理和双下肢肌肉受累的特点。方法回顾性分析2012年01月至2020年10月就诊于南京鼓楼医院神经内科的11例DM1患者的临床、骨骼肌活检病理及5例双下肢骨骼肌磁共振的特点。结果11例患者均有不同程度的肌强直、伴有肌无力/肌萎缩症状,肌无力/肌萎缩远端重于近端。骨骼肌病理特点:10/11例患者可见Ⅰ型肌纤维轻度萎缩,部分患者可见核内移、核聚集、肌浆块现象。双下肢肌肉磁共振:5例患者双下肢远端脂肪浸润重于近端,双侧肌肉受累程度不对称,大腿肌肉脂肪浸润以股中间肌最严重,小腿肌肉以腓肠肌、比目鱼肌、腓骨长肌最严重。结论骨骼肌磁共振对诊断强直性肌营养不良Ⅰ型有重要的提示意义。     

Ullrich型先天性肌营养不良三例临床及病理特点

目的 探讨Ullrich型先天性肌营养不良(UCMD)患者的临床和病理特点.方法 收集并分析我院收治的3例UCMD、2例Duchenne型肌营养不良(DMD)和1例先天性肌营养不良1A型的临床和病理资料.全部患者均进行肌肉活体组织检查,并对标本行组织化学和免疫组织化学染色,其中2例UCMD和1例DMD患者的标本行免疫荧光染色.结果 UCMD患者均以新生儿肌张力低下为首发表现,其临床标志为近端关节挛缩和远端关节弹性过度.组织化学染色提示UCMD患者存在肌纤维发育不良伴结缔组织增生,坏死和变性不及DMD患者显著.抗Ⅵ型胶原抗体免疫组织化学染色显示3例UCMD患者中1例为完全缺失,2例仅为部分缺失.免疫荧光染色能更清晰地显示Ⅵ型胶原的部分性缺失.结论近端关节挛缩和远端关节弹性过度是UCMD的标志性临床特征.抗Ⅵ型胶原抗体的免疫组织化学染色是确诊UCMD的重要方法 .     

肢带型肌营养不良2A型临床和病理特点

目的探讨肢带型肌营养不良2A型(LGMD2A)的临床及病理特点。方法回顾性分析7例基因确诊的LGMD2A型患者的临床资料和骨骼肌病理检查结果。结果 1例尚未出现临床症状。1例症状很轻,仅有易疲劳伴运动时小腿痛,肌力检查正常。另外5例均以下肢近端肌无力缓慢起病,进行性加重,之后上肢近端肌不同程度受累,均伴有翼状肩胛及跟腱挛缩,仅1例见腓肠肌肥大及脊柱畸形,下肢近端肌群肌力检查提示伸髋及髋内收受累最重,其次为屈髋及屈膝,髋外展及伸膝受累最轻。该5例患者的骨骼肌病理均呈肌营养不良样病理改变,表现为肌纤维大小不等、结缔组织增生及不同程度坏死、再生,NADH染色2例见大量分叶纤维。结论 LGMD2A的临床变异较大,其典型临床特点为慢性进行性近端肌无力伴翼状肩胛、关节挛缩,股后肌群及内侧肌群较股前肌群受累明显。其肌肉病理缺乏特异性。     

Ptosis aggravates dysphagia in oculopharyngeal muscular dystrophy

BACKGROUND: Ptosis and dysphagia are important features in oculopharyngeal muscular dystrophy (OPMD). OBJECTIVE: Retroflexion of the head is a well known compensatory mechanism for ptosis, but generally retroflexion has a negative effect on swallowing. We hypothesised that severity of ptosis is related to degree of retroflexion and that this compensation is responsible for deteriorating dysphagia. METHODS: Nine OPMD patients were examined in the conditions "head position adapted to ptosis" and "head position slightly flexed". Ptosis was quantified by photogrammetry and retroflexion of the head by digital photographs. The severity of dysphagia was measured using visual analogue scales (VAS) and by calculating swallowing volumes and oropharyngeal swallow efficiency (OPSE) based on videofluoroscopy. RESULTS: Statistical analyses show a significant relationship between ptosis and degree of retroflexion. The degree of retroflexion of the head correlated significantly with VAS scores and with the maximum swallowing volume. The slightly flexed head position significantly improved VAS scores as well as swallowing volumes and OPSE. CONCLUSION: In OPMD patients, ptosis significantly correlates with retroflexion of the head, which has a negative effect on swallowing. Subjective and objective reduction of swallowing problems was found when patients were instructed to eat and drink with a slightly flexed head position.     

Rimmed vacuoles in facioscapulohumeral muscular dystrophy: a unique ultrastructural feature

Rimmed vacuoles (RV) are a characteristic pathological feature in inclusion body myositis, but may also occur in other neuromuscular disorders, such as distal myopathies, oculopharyngeal myopathy, polymyositis, rigid spine syndrome, congenital myopathies, and some limb girdle muscular dystrophies, as well as in various neurogenic diseases. We describe a patient with RV in familial facioscapulohumeral muscular dystrophy (FSHD) associated with an FSHD-typical deletion on chromosome 4q35. Thus, FSHD should be included in the differential diagnosis of neuromuscular disorders with RV.     

Mutation and haplotype analysis of oculopharyngeal muscular dystrophy in Thai patients

Oculopharyngeal muscular dystrophy (OPMD) is an inherited neuromuscular disease associated with a short trinucleotide repeat expansion in Exon 1 of the PABPN1 gene. OPMD is uncommon in East Asian populations, and there have been no previous reports of Thai patients. We studied clinical and molecular genetic features of six unrelated Thai patients with autosomal dominant OPMD. All patients had expansions of the guanine-cytosine-guanine (GCG) repeat ranging from three to seven additional repeats in the PABPN1 gene. Haplotype analysis showed that these mutations might have originated independently. Analysis of the size of the GCG repeat in the PABPN1 gene in 200 Thai control patients showed that 0.5% of the control subjects possessed (GCG)₇, thereby suggesting that the prevalence of autosomal recessive OPMD in the Thai population was approximately 1 in 160,000. In conclusion, our data suggest that OPMD in Thailand may be more common than previously thought.     

Unusual triplet expansion associated with neurogenic changes in a family with oculopharyngeal muscular dystrophy

The occasional observation of neurogenic features in oculopharyngeal muscular dystrophy (OPMD) is unclear both in nosological and in etiological respects. Studies are reported here of a family with autosomal‐dominant OPMD involving seven members over three generations. In three of them muscle biopsies were performed. Two of the patients (a 45‐year‐old sister and a 57‐year‐old brother of the third generation) were studied in more detail and, in addition to the typical changes of OPMD, showed a neurogenic component both by electrophysiology and morphology. Molecular genetic investigations revealed a repeat unit of (GCG/GCA)₁₃ in the first exon of the poly(A)binding‐protein2 gene in both siblings. A possible association of this unusually long triplet repeat extension with the atypical phenotype is considered and has to be verified in other cases.     

Mitochondrial abnormalities in oculopharyngeal muscular dystrophy

A family with oculopharyngeal muscular dystrophy (OPMD) is described. Histological and histochemical studies of muscle biopsy showed nonspecific myopathic changes; no "ragged-red" fibers were seen. Electron microscopy demonstrated bizarre large mitochondria with abnormal cristae, but no intranuclear inclusion bodies. Our findings are compatible with the possibility that OPMD is a heterogeneous syndrome, and may be a manifestation of mitochondrial myopathy.     

Nuclear inclusion in oculopharyngeal dystrophy

Summary The ultrastructural examination of skeletal muscle biopsies of three typical cases of autosomal dominant inherited oculopharyngeal muscular dystrophy showed collections of tubular filaments (8.5 nm in diameter) within muscle fibre nuclei. These filaments appear to be a characteristic morphological feature of oculopharyngeal dystrophy.     

Progressive myopathy in an inducible mouse model of oculopharyngeal muscular dystrophy

The genetic basis of oculopharyngeal muscular dystrophy (OPMD) is a short expansion of a polyalanine tract (normal allele: 10 alanines, mutant allele: 11-17 alanines) in the nuclear polyadenylate binding protein PABPN1 which is essential for controlling poly(A) tail length in messenger RNA. Mutant PABPN1 forms nuclear inclusions in OPMD muscle. To investigate the pathogenic role of mutant PABPN1 in vivo, we generated a ligand-inducible transgenic mouse model by using the mifepristone-inducible gene expression system. Induction of ubiquitous expression of mutant PABPN1 resulted in skeletal and cardiac myopathy. Histological changes of degenerative myopathy were preceded by nuclear inclusions of insoluble PABPN1. Downregulation of mutant PABPN1 expression attenuated the myopathy and reduced the nuclear burden of insoluble PABPN1. These results support association between mutant PABPN1 accumulation and degenerative myopathy in mice. Resolution of myopathy in mice suggests that the disease process in OPMD patients may be treatable.     

Oculopharyngodistal myopathy is genetically heterogeneous and most cases are distinct from oculopharyngeal muscular dystrophy

The question whether oculopharyngodistal myopathy (MIM 164310) is a distinct disease entity or a variant of oculopharyngeal muscular dystrophy (MIM 164300) persists. To answer this question, we examined five patients with the clinical characteristics of oculopharyngodistal myopathy for GCG expansion in poly(A)-binding protein nuclear 1 gene (previously called poly(A)-binding protein 2), the causative gene defect for oculopharyngeal muscular dystrophy. Only one of our five patients had the significant GCG expansion. Thus, oculopharyngodistal myopathy is a genetically heterogeneous disorder, which includes patients with oculopharyngeal muscular dystrophy but, for the most part, is different genetically from oculopharyngeal muscular dystrophy.     

Two cases of oculopharyngeal muscular dystrophy (OPMD) with the rare PABPN1 c.35G>C; p.Gly12Ala point mutation

Oculopharyngeal muscular dystrophy is a neuromuscular disease usually presenting in the 5th or 6th decades of life with a dominant inheritance pattern. In almost all cases the cause of the disease is the expansion of a DNA repeat sequence containing GCG and GCA codons in exon 1 of the PABPN1 gene from 10 to between 12 and 17 repeats. However one case has been previously reported without the gene expansion but instead with a c.35G > C missense mutation converting a glycine codon to an alanine and resulting in a sequence of 13 contiguous alanine codons, thus mimicking the effect of the common expansion mutation. Here we report two further cases of OPMD caused by the c.35G > C point mutation. Clinical and pedigree data indicate the usual OPMD dominant inheritance pattern.