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Query: UMLS:C0026850 (muscular dystrophy)
 5,870 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Electromyoneurography is the combined use of electromyography and electroneurography. Electromyography is useful in defining the cause and site of different myopathies, such as muscular dystrophy, myotonia and myasthenia, and lesions involving the motor neuron in the anterior horn of the spinal cord. Electroneurography helps to localize the site of peripheral nerve disorders, such as radiculopathy and axonopathy. Use of the two procedures together enhances diagnostic capacity and, in some situations, may obviate the need for myelography.
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PMID:Electromyoneurography. 71 21

Some of the neuromuscular diseases may lead to respiratory failure. This is the case in some lesions of the anterior horn cells (poliomyelitis and spinal muscular atrophy), in diseases affecting the nerve roots (acute polyradiculitis and lesions of the C4-roots) or affecting the phrenic nerve. Respiratory failure is frequent in myasthenia and may accompany Duchenne's muscular dystrophy. In each case one has to evaluate the opportunity of respiratory treatment considering all the elements of the disease and of the individual patient.
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PMID:[Neuromuscular diseases which lead to respiratory insufficiency]. 227 7

The paper reports a case of the western-type congenital muscular dystrophy in a 5-year-old boy who showed generalized myasthenia and hypotrophies, flexor contractures in the large joints of legs and arms, areflexia of deep reflexes. Examining the biopsy specimens of the musculus quadriceps femoris revealed changes typical of muscular dystrophy. The level of serum creatine kinase was elevated. Electromyography showed changes characteristic of muscular lesion. An emphasis is laid on his asthenic constitution, hydrocephalic skull, lowly located ears, and a small mouth. Despite preserved intellect and no focal neurological symptomatology, brain computed tomography indicated a diffuse decrease in the density of the substantia alba in the cerebral hemispheres. The paper also provides references to papers which emphasize that neurological symptoms will inevitably develop in such patients in future.
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PMID:[Congenital muscular dystrophy with leukoencephalopathy]. 815 12

Family studies have demonstrated the genetic etiology of concomitant strabismus (prevalence in different populations 1-5%, positive family history in 37% on average), as have twin studies (mean concordance in monozygous twins 73% compared to 35% in dizygous twins). In Duane's syndrome, three chromosomal loci have been identified to date: 2q31, 8q13, and 22q11; loci have also been identified in Moebius syndrome (various inheritance patterns): 13q12.2-q13, 3q21-q22, and 10q21.3-q22, as well as in congenital fibrosis of the extraocular muscles (CFEOM; 3 loci, 1 gene).(1) Already identified are the genes for a number of rarer muscular dystrophy syndromes with ocular involvement, various forms of congenital myasthenia, and mitochondrial diseases (with the primary defect located either in the mtDNA, resulting in a mitochondrial inheritance pattern, or in the nuclear DNA with Mendelian inheritance). A number of hereditary retinal diseases (Mendelian inheritance) may also be associated with strabismus. More than one gene is likely to be involved in the frequently occurring concomitant strabismus, making the analysis more difficult. Patients with chromosomal rearrangements, large families and isolated populations (see also the contributions by Preising and Zitzlsperger et al. in this issue)(2,3) will be instrumental in gene identification. In view of the high prevalence of concomitant strabismus, the disclosure of its etiology will have considerable medical, psychosocial and health-cost impact.
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PMID:Genetics of isolated and syndromic strabismus: facts and perspectives. 1222 94

Few comprehensive epidemiological studies of the prevalence of muscle diseases have been undertaken, and none has been carried out in our locality. The present cross-sectional study was conducted in Assiut Governorate (Upper Egypt) to estimate the prevalence of different types of primary muscular disorder in 1997. The study involved 52,203 subjects, 15,617 (30%) from the rural community and 36,586 (70%) from the urban community. Patients were identified from a door-to-door survey, and all were subjected to a full clinical examination, with confirmation of the diagnosis through electrophysiological, and biochemical investigations. Histopathological studies were performed for the classification of muscular dystrophies. Forty patients with muscular disorders were identified, with a point prevalence of 76.6 per 100,000 in the total community with no significant differences between the rural and urban communities. The creatine kinase level was abnormally high (>225 IU/l) in 80% of the cases, increased in all patients with muscular dystrophy or myositis, in 88.8% of patients with systemic myopathy and 66.6% of patients with myotonia. None of the cases of myasthenia showed an increase in the creatine kinase level. The lifetime prevalence per 100,000 was 26.8 for muscular dystrophy, 11.49 for myotonia, 11.49 for myositis, 17.24 for systemic myopathy and 9.57 for myasthenia.
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PMID:Epidemiological study of muscular disorders in Assiut, Egypt. 1621 Aug 62

Recessive X-linked amyotrophic spinobulbar muscular atrophy (SBMA) or Kennedy disease is a neuroendocrine disorder with a slowly progressive phenotype, caused by an expansion of a polymorphic tandem CAG repeat of the androgen receptor gene. Classical clinical hallmarks include onset in the third decade of life, weakness and wasting predominantly in proximal extremity muscles, variable weakness of bulbar muscles, abundant muscle fasciculations, sensory nerve action potential abnormalities and signs of androgen insensitivity such as gynecomastia and testicular atrophy. The diagnosis has been recently made easier by the availability of genetic testing but Kennedy disease is probably still underdiagnosed because of phenotypic variability. We report 11 new cases, of which seven had atypical initial manifestations presenting respectively with myasthenia, cramps and fasciculation syndrome, polyneuropathy, post-trauma monomelic neuronopathy, effort-dependent muscle intolerance and/or muscular dystrophy, with the aim to enlarge the phenotypic spectrum of the published series.
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PMID:[Multiple phenotypic manifestations of X-linked spinobulbar muscular atrophy]. 1866 19

The Congenital Myasthenic Syndromes (CMS), a group of heterogeneous genetic disorders of neuromuscular transmission, are often misdiagnosed as congenital muscular dystrophy (CMD) or myopathies and present particular management problems. We present our experience of 46 children with CMS, referred to us between 1992-2007 with provisional diagnoses of congenital myopathy (22/46), CMS or limb-girdle myasthenia (9/46), central hypotonia or neurometabolic disease (5/46), myasthenia gravis (4/46), limb-girdle or congenital muscular dystrophy (4/46) and SMA (2/46). Diagnosis was often considerably delayed (up to 18y4 m), despite the early symptoms in most cases. Diagnostic clues in the neonates were feeding difficulties (29/46), hypotonia with or without limb weakness (21/46), ptosis (19/46), respiratory insufficiency (12/46), contractures (4/46) and stridor (6/46). Twenty-five children had delayed motor milestones. Fatigability developed in 43 and a variable degree of ptosis was eventually present in 40. Over the period of the study, the mainstay of EMG diagnosis evolved from repetitive nerve stimulation to stimulation single fibre EMG. The patients were studied by several different operators. 66 EMGs were performed in 40 children, 29 showed a neuromuscular junction abnormality, 7 were myopathic, 2 had possible neurogenic changes and 28 were normal or inconclusive. A repetitive CMAP was detected in only one of seven children with a COLQ mutation and neither of the two children with Slow Channel Syndrome mutations. Mutations have been identified so far in 32/46 children: 10 RAPSN, 7 COLQ, 6 CHRNE, 7 DOK7, 1 CHRNA1 and 1 CHAT. 24 of 25 muscle biopsies showed myopathic changes with fibre size variation; 14 had type-1 fibre predominance. Three cases showed small type-1 fibres resembling fibre type disproportion, and four showed core-like lesions. No specific myopathic features were associated with any of the genes. Twenty children responded to Pyridostigmine treatment alone, 11 to Pyridostigmine with either 3, 4 DAP or Ephedrine and five to Ephedrine alone. Twenty one children required acute or chronic respiratory support, with tracheostomy in 4 and nocturnal or emergency non-invasive ventilation in 9. Eight children had gastrostomy. Another 11 were underweight for height indicative of failure to thrive and required dietetic input. A high index of clinical suspicion, repeat EMG by an experienced electromyographer and, if necessary, a therapeutic trial of Pyridostigmine facilitates the diagnosis of CMS with subsequent molecular genetic confirmation. This guides rational therapy and multidisciplinary management, which may be crucial for survival, particularly in pedigrees where previous deaths have occurred in infancy.
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PMID:Congenital myasthenic syndromes in childhood: diagnostic and management challenges. 1870 67

Autosomal recessive mutations in the cytolinker protein plectin account for the multisystem disorders epidermolysis bullosa simplex (EBS) associated with muscular dystrophy (EBS-MD), pyloric atresia (EBS-PA), and congenital myasthenia (EBS-CMS). In contrast, a dominant missense mutation leads to the disease EBS-Ogna, manifesting exclusively as skin fragility. We have exploited this trait to study the molecular basis of hemidesmosome failure in EBS-Ogna and to reveal the contribution of plectin to hemidesmosome homeostasis. We generated EBS-Ogna knock-in mice mimicking the human phenotype and show that blistering reflects insufficient protein levels of the hemidesmosome-associated plectin isoform 1a. We found that plectin 1a, in contrast to plectin 1c, the major isoform expressed in epidermal keratinocytes, is proteolytically degraded, supporting the notion that degradation of hemidesmosome-anchored plectin is spatially controlled. Using recombinant proteins, we show that the mutation renders plectin's 190-nm-long coiled-coil rod domain more vulnerable to cleavage by calpains and other proteases activated in the epidermis but not in skeletal muscle. Accordingly, treatment of cultured EBS-Ogna keratinocytes as well as of EBS-Ogna mouse skin with calpain inhibitors resulted in increased plectin 1a protein expression levels. Moreover, we report that plectin's rod domain forms dimeric structures that can further associate laterally into remarkably stable (paracrystalline) polymers. We propose focal self-association of plectin molecules as a novel mechanism contributing to hemidesmosome homeostasis and stabilization.
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PMID:Targeted proteolysis of plectin isoform 1a accounts for hemidesmosome dysfunction in mice mimicking the dominant skin blistering disease EBS-Ogna. 2214 12

One of the first questions asked by patients and family members when a diagnosis of amyotrophic lateral sclerosis is made is "what about stem cells?" The term "stem cells" has attractiveness to it, with the assumption that stem cell treatment (stem nerve cells) can replace lost nerve cells. There are perhaps 2 types of stem cell trials, those that are vetted by the Food and Drug Administration and those that have no official oversight and whose results are infrequently published. The issue of the latter was discussed in the last edition of this column. The results of one of the formal stem cell trials now in the United States have been reported. Spinal muscular atrophy is a form of motor neuron disease affecting children and has a genetic cause, which has led to a feasibility study giving antisense oligonucleotides, and the results have also been reported. Biomarkers of amyotrophic lateral sclerosis are being sought, and the presence of neurofilaments is promising. Inflammatory neuropathies are an important group because they are treatable. Intravenous immune globulin is a commonly used agent, but a number of questions persist: one is efficacy among brands, another is the probability of a response, and a third is optimum dosing and taper schedules. A number of recent articles address these issues. The predictive value of single-fiber electromyography in determining which patients with ocular myasthenia will develop generalized disease, the risk of crisis after thymectomy, and 2 papers discussing new forms of congenital myasthenic syndrome are discussed. The risk of brain tumors, quality of life, and the assessment of trunk muscle strength in patients with type 1 myotonic dystrophy is reviewed. An article describing the discovery of mutations in SCN4A as a cause of congenital myopathy is discussed, as is one describing the occurrence of rhabdomyolysis in a group of patients subsequently discovered to have various forms of muscular dystrophy. Finally, articles describing the features of patients with inflammatory myopathies and Jo-1 and either 3-hydroxy-3-methylglutaryl-conezymea reductase or to signal recognition particle antibodies are reviewed.
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PMID:What's in the Literature? 2722 41

Thirty five floppy children seen during two year period, were subjected to clinical examination, electroneuromyography and muscle biopsy. The muscle biopsy was sent for routine histology, histochemistry and electron microscopy. Using muscle pathology as the 'gold standard' for diagnosis, the aetiological entities were spinal muscular atrophy (16), congenital muscular dystrophy (6), mitochondrial myopathy (3), congenital fibre type disproportion (2), acid mutase deficiency (1) and benign congenital hypotonia (6). Mental subnormality, seizures, ptosis and ophthalmoplegia suggested mitochondrial disease (n=2). Macroglossia, hepatomegaly and cardiomegaly along with the dive bomber effect on electromyography were useful clues to the diagnosis of Pompe's disease (n=1). Positive decremental test established the diagnosis of congenital myasthenia in one patient. Contrary to most previously published reports, infantile onset of spinal muscular atrophy did not always spell a poor prognosis on follow up. 'Floppy infant syndrome' has varied etiology. Comprehensive evaluation including clinical, electrophysiological and detailed histological examination is necessary for proper diagnosis and prognosis of this heterogenous entity.
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PMID:Neuromuscular disorders in infancy and childhood. 2951 74


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