肌电图和靶基因检测在强直性肌营养不良中的诊断价值

目的探讨强直性肌营养不良的临床特征,评价肌电图和靶基因检测方法在诊断中的应用价值。方法回顾性分析来自4个不同家系的6例患者的临床特点、肌电图和靶基因检测结果。结果该组6例患者均存在不同程度肌强直、肌无力和肌萎缩及多系统受累等临床表现。肌电图显示,肌源性损害伴肌强直放电阳性率为100%;神经传导(NCS)提示,3例有部分运动神经CMAP波幅降低,余均正常。靶基因检测提示,该组患者的强直性肌营养不良蛋白激酶(DMPK)基因3′非翻译区(3′-UTR)的CTG重复异常扩增率为100%,均50次;锌指蛋白9(ZNF9)基因的第1个内含子中CCTG重复扩增均正常。结论在强直性肌营养不良的诊断中,阳性家族史、典型的临床特征是诊断的基础,肌电图是诊断筛选的首选方法,特别是在强直性肌营养不良1型中阳性率更高,靶基因分析是诊断和分型的金标准。[国际神经病学神经外科学杂志, 2021, 48(2):120-125]     

Recombinant DNA study of Duchenne muscular dystrophy occurring in a myotonic dystrophy family

A recombinant DNA study was performed in a three-generation family with 8 typical cases of late onset myotonic dystrophy (DM) and with one case of Duchenne muscular dystrophy (DMD). The study with DNA markers for chromosome 19 showed linkage of DM locus to the 3.8 Kb allele of apolipoprotein C2 (APOC2) probe and to 9 Kb allele of pSC11 probe (APOC2 lod score = 0.69 at theta = 0). The 21-year-old DMD patient showed no myotonic signs. His clinical history revealed onset with weakness around 4 years of age, progressive course with wheelchair confinement at 11, and cardiomyopathy. His karyotype was normal (46, XY). The study with 10 DNA markers for the chromosome X found a deletion limited to XJ 1.1, XJ 1.2, and XJ 2.3 probes. His 22-year-old sister with typical clinical, EMG and recombinant DNA findings characteristic for myotonic dystrophy was also a carrier of DMD deletion.     

A scapular onset muscular dystrophy without facial involvement: Possible allelism with facioscapulohumeral muscular dystrophy

A dominantly inherited muscular dystrophy with onset in the shoulder girdle and later progression to the lower limbs is described. The disorder was clinically distinguishable from known facioscapulohumeral, scapulohumeral and limb girdle syndromes. A 38 kb allele detected by probe p13E-11 (D4F104S1) segregated with the disease. Linkage analysis gave a maximum lod score of z = 1.61 at θ = 0.01 with the 4q35 marker D4S184 (affected only analysis z = 1.20 at θ = 0.01) suggesting probable allelism with facioscapulohumeral muscular dystrophy.     

Muscle histopathology in myotonic dystrophy in relation to age and muscular weakness

We studied histopathological changes in the biceps brachii muscle in relation to age and the degree of muscle weakness in 64 patients (aged 11–59 years) with myotonic dystrophy. The proportion of type 1 fibers was unaltered in the adolescent patients compared with control values, but increased with age. The average diameters of all the fiber types were smaller than control values in the adolescents, suggesting immature development; however, there was an increase in diameter with age that was associated with an increase of hypertrophic type 2 fibers. At all ages, type 1 fibers were smaller than type 2 ones. Small angular fibers and small group atrophy consisted mainly of type 1 fibers, their incidences decreasing with age. The severity of muscular weakness was related to the predominance of type 1 fibers, the reduction in the number of hypertrophic type 2 fibers, and the accumulation of adipose cells, but not to the presence of small angular fibers or to small group atrophy. © 1994 John Wiley & Sons, Inc.     

强直性肌营养不良1型患者的临床特点及CTG重复次数分析

目的总结强直性肌营养不良1型患者的临床、神经电生理和遗传学特点。方法收集3例强直性肌营养不良1型患者的临床症状、肌电图、肌肉病理及基因检测结果。结果 3例患者(男性1例)均为成年起病,慢性病程。临床表现为四肢远端无力和肌强直; 2例患者存在眼外肌或面肌无力; 1例伴随前额脱发; 2例存在心脏传导紊乱如阵发性室性心动过速、左前束支传导阻滞、右束支传导阻滞; 2例出现脑白质病变。3例强直性肌营养不良1型患者DMPK基因3’非翻译区的突变CTG重复次数分别为104、150、299,均大于50次。3例患者肌电图检查所检肌肉均可见肌强直放电。结论强直性肌营养不良1型患者肌无力主要出现在远端肌群,心脏传导紊乱和脑白质病变是其多系统受累的显著表现。肌电图可以发现临床下肌强直放电,是最敏感的筛查手段。     

Infantile facioscapulohumeral muscular dystrophy: new observations

Clinical, electrodiagnostic, and biopsy findings in a family with infantile facioscapulohumeral muscular dystrophy are reported. Four of eight family members having the disorder, all with onset in infancy, developed severe weakness leading to death in adolescence. The clinical course and prognosis of infantile facioscapulohumeral muscular dystrophy may, therefore, be as devastating as that of Duchenne muscular dystrophy. The unusual infantile presentation and high mortality in our affected family members suggest that the gene coding for this disorder may be different from that responsible for conventional facioscapulohumeral muscular dystrophy.     

强直性肌营养不良1型患者的临床特点及CTG重复次数分析

目的 总结强直性肌营养不良1型患者的临床、神经电生理和遗传学特点。方法 收集3例强直性肌营养不良1型患者的临床症状、肌电图、肌肉病理及基因检测结果。结果 3例患者（男性1例）均为成年起病,慢性病程。临床表现为四肢远端无力和肌强直;2例患者存在眼外肌或面肌无力;1例伴随前额脱发;2例存在心脏传导紊乱如阵发性室性心动过速、左前束支传导阻滞、右束支传导阻滞;2例出现脑白质病变。3例强直性肌营养不良1型患者DMPK基因3'非翻译区的突变CTG重复次数分别为104、150、299,均大于50次。3例患者肌电图检查所检肌肉均可见肌强直放电。结论 强直性肌营养不良1型患者肌无力主要出现在远端肌群,心脏传导紊乱和脑白质病变是其多系统受累的显著表现。肌电图可以发现临床下肌强直放电,是最敏感的筛查手段。     

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.     

Ullrich's congenital atonic sclerotic muscular dystrophy

Summary A 5-year old girl with Ullrich's atonic-sclerotic muscular dystrophy is reported and 16 previously reported cases are reviewed. The clinical features, in particular proximal contractures, distal hyperextensibility, mild dysmorphism and hyperhidrosis, allow recognition of this subtype of congenital muscular dystrophy, which has no specific pathological characteristics. There is evidence in favour of an autosomal recessive mode of inheritance.     

Atypical form of X-linked proximal pseudohypertrophic muscular dystrophy

Summary A series of 95 families, consisting of 317 patients with severe and mild X-linked proximal pseudohypertrophic muscular dystrophy (MD), was analysed by the use of two different and rigid clinical criteria based on the age when the patient became chairbound. Using these criteria the families from Erfurt and Warsaw could be clearly separated into classical Duchenne (DMD) and classical Becker (BMD) type patients. A third group of patients was found with atypical clinical course, who could not be identified as neither Duchenne nor Becker cases. Statistically highly significant differences were found between the groups of classical DMD and atypical MD cases on the one hand and between the groups of atypical MD and classical BMD cases on the other, especially with respect to age when chairbound and age at death. The comparisons of progression of the disease, life expectancy and of fertility between the three groups of X-linked MD show that classical DMD and atypical MD may be considered as separate types of severe X-linked proximal pseudohypertrophic MD. On the basis of these findings the authors offer conclusions for the general practice of neurology, paediatrics and genetic counselling.     

Becker and limb-girdle muscular dystrophy associated with pituitary dwarfism

Summary In 1981 a report appeared of a patient with Duchenne muscular dystrophy associated with dwarfism caused by growth hormone deficiency, in whom the muscular disease was unusually benign. The authors suggested that the benign course might be related to the growth hormone deficiency and dwarfism. Other authors later supported this idea, having observed that in dystrophic mice and hamsters with congenital and experimentally induced pituitary dwarfism, respectively, pathological expressions of the dystrophy were markedly reduced. In this paper one case of Becker and one of limb-girdle dystrophy, each associated with short stature and growth hormone deficiency are described. In these cases the disease did not have a particularly benign course. It is concluded that caution is necessary, at least in certain cases, before an association between reduced muscular growth and the dystrophic process can be assumed.     

Autosomal recessive distal muscular dystrophy

The distal myopathies include autosomal dominant, autosomal recessive, and sporadic disorders. Two of the recessive disorders are considered to be definitive entities: Miyoshi's myopathy, which has an early adult onset and first involves the calf muscles, and distal myopathy with rimmed vacuoles.We here describe the cases of two sisters and compare them with previously reported cases. The disorder in our patients is characterised by: a) autosomal recessive inheritance; b) onset in early adult life; c) initial involvement of the tibialis anterior and peroneal muscles; d) subsequent involvement of the calf muscles spreading to the proximal muscles of the legs and, later, the arms; e) a moderately disabling evolution over a period of 10–12 years; f) marked and stably high serum levels of CK and other enzymes; g) EMG evidence of myopathic damage, with fibrillation at rest; and h) a histological picture of dystrophic myopathy, with atrophy of mainly type 2 fibres.We think that this syndrome is different from the two forms of autosomal recessive distal myopathy mentioned above.

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Sommario Le miopatie distali comprendono forme familiari a trasmissione autosomica dominante e autosomica recessiva e casi sporadici. Due sono le entità nosografiche autosomiche recessive identificate: la Miopatia di Miyoshi ad esordio giovanile e con compromissione iniziale dei muscoli del polpaccio, e la Miopatia distale con fibre vacuolate.Descriviamo in questa sede i casi di due sorelle e li confrontiamo con quelli della letteratura. La malattia delle nostre pazienti è caratterizzata da: a) Trasmissione autosomica recessiva; b) esordio in età giovanile; c) compromissione iniziale dei muscoli tibioperoneali; d) successiva compromissione dei muscoli dei polpacci, e poi nell'ordine dei gruppi prossimali degli arti inferiori e superiori; e) evoluzione mediamente invalidante in un tempo di 10–12 anni dall'esordio; f) stabile marcato innalzamento dei valori serici di CK e degli altri enzimi muscolari; g) reperto EMG di danno miopatico primitivo con presenza di fibrillazione a riposo; h) quadro bioptico di miopatia distrofica con atrofia prevalente delle fibre di tipo 2.A nostro parere questa sindrome è una entità nosografica diversa dalle due forme codificate di miopatia distale autosomica recessiva.

     

Cardiac involvement in Fukuyama muscular dystrophy is less severe than in Duchenne muscular dystrophy

Background

One of the main complications in patients with muscular dystrophies is cardiac dysfunction. The literature on cardiac involvement in patients with Fukuyama congenital muscular dystrophy (FCMD) is limited.

Scapulothoracic arthrodesis for patients with facioscapulohumeral muscular dystrophy

Ten scapulothoracic arthrodesis procedures were performed in six patients with facioscapulohumeral muscular dystrophy in order to improve considerably restricted activities of daily living. Four of these procedures were bilateral. The duration of follow-up ranged from 28 to 120 months. All patients reported improved function in activities of daily living. Active shoulder abduction was improved by an average of 44°, and active flexion increased by 56°. There was no deterioration in improved upper limb function with time. Complications included pneumothorax, atelectasis, pleural effusion and re-exploration for a segment of retained drain.     

Bacterial overgrowth syndrome in myotonic muscular dystrophy is potentially treatable

Over one third of patients with myotonic muscular dystrophy type 1 (DM1) have gastrointestinal complaints. The cause is multifactorial, and treatment options are limited. Twenty DM1 patients with gastrointestinal symptoms were screened over a 2-year period using glucose breath hydrogen testing (GBHT) to evaluate the prevalence of small intestinal bacterial overgrowth (SIBO). Sixty-five percent of patients had a positive GBHT, and diarrhea was the most common presenting symptom. Ciprofloxacin was the most common antibiotic used for treatment, and 70% of patients reported a good response to the initial course of treatment. Although the causes of gastrointestinal symptoms in patients with DM1 are multifactorial, small intestinal bacterial overgrowth is an important diagnostic consideration that is easily diagnosed using glucose breath hydrogen testing and often shows a good response to treatment with common antibiotics.