Quantitative electromyography in the detection of the carriers in duchenne type muscular dystrophy

Summary The quantitative EMG technique was used to detect Duchenne muscular dystrophy carriers. The tests were carried out, measuring the parameters of M.U. potentials (the duration, the phase, and the Ø index according to Van den Bosch, modified by Gardner-Medwin), and using the Willison analyzer, in a group of carriers and normal subjects. Ten M.U. potentials from the deltoid, biceps brachii and quadriceps muscles were photographed and measured in each subject, and the right and the left biceps were examined with the Willison analyzer. An high detection rate was obtained by manual EMG, measuring traditional values such as mean number of phases, A.P. duration and Ø index. The Willison analyzer was significant in 2 known carriers. The total EMG detection rate was higher than the CPK tests both in the known carriers and in the possible carriers. It is concluded that the quantitative EMG technique is an useful and specific test to detect carriers of the gene of Duchenne muscular dystrophy.

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Zusammenfassung Die quantitative EMG-Technik wurde zur Erfassung von Konduktorinnen der Duchenneschen Muskeldystrophie angewendet. Bei einer Gruppe von Konduktorinnen und von Normalpersonen wurden sowohl die Parameter der motorischen Einheiten gemessen (Dauer, Anzahl Phasen, Ø Index nach Van den Bosch, modifiziert nach Gardner-Medwin) als auch unter Anwendung des Willison-Analysators. Es wurden 10 Potentiale motorischer Einheiten aus dem Deltoides, dem Biceps brachii und dem Quadriceps bei jeder Versuchsperson fotografiert und ausgemessen und sowohl der rechte wie der linke Biceps wurden mit dem Willison-Analysator untersucht. Eine hohe Erfassungsrate wurde bei Anwendung der manuellen EMG-Techniken mit Messung der konventionellen Werte erreicht. Bei 2 Konduktorinnen war der Willison-Analysator entscheidend. Gesamthaft war der Prozentsatz der positiven EMG-Befunde höher als derjenige der Kreatinphosphokinasebestimmungen, sowohl bei den sicheren Konduktorinnen als bei den möglichen Konduktorinnen. Es wird gefolgert, daß die quantitative EMG-Technik ein nützliches Instrument zum Nachweis der Konduktorinnen einer Duchenneschen Muskeldystrophie darstellt.

     

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.     

Functional involvement of cerebral cortex in duchenne muscular dystrophy

Transcranial stimulation was performed in 4 patients with Duchenne muscular dystrophy and 4 control subjects. The patients' central motor conduction time was normal. The threshold for evoking electromyographic responses using electrical anodal stimulation was the same in both groups, but the threshold for stimulation with a circular magnetic coil at the vertex was higher in the patients. This is compatible with reduced cortical excitability that may be related to the deficiency of brain synaptic dystrophin. © 1998 John Wiley & Sons, Inc. Muscle Nerve 21:662–664, 1998.     

Cognitive functions in duchenne muscular dystrophy: A reappraisal and comparison with spinal muscular atrophy

In order to clarify cognitive functions in Duchenne muscular dystrophy (DMD), we performed a new controlled neuropsychological study. IQ (WISC-R), verbal skills (fluency, confrontation naming and syntax comprehension) and memory abilities (BEM) were studied in two matched groups; 24 DMD children and 17 spinal muscular atrophy (SMA) children aged 12–16 yr. A significant difference appeared between the DMD and SMA patients: only in the DMD group were there significant disabilities in certain specific functions and normal scores in others. Despite similar education, the DMD children more often had significantly greater learning disabilities. There were more DMD left-handers. Verbal IQ was significantly low whereas performance IQ was at a normal level. DMD children also performed poorly in reading tasks and in some memory functions such as story recall and verbal recognition. Specific cognitive disabilities in certain DMD children, not seen in SMA children, suggest a relationship with a DMD genetic disorder.     

Utility of cystatin C to monitor renal function in duchenne muscular dystrophy

Creatinine as a marker of renal function has limited value in Duchenne muscular dystrophy (DMD) because of reduced muscle mass. Alternative methods of assessing renal function are sorely needed. Cystatin C, a nonglycosylated protein unaffected by muscle mass, is potentially an ideal biomarker of nephrotoxicity for this population but requires validation. In all, 75 subjects were recruited: 35 DMD (mean age 10.8 ± 5.4 years, corticosteroids n = 19, ambulatory n = 26), 29 healthy controls, 10 with renal disease, and one DMD with renal failure. Cystatin C levels in DMD were normal irrespective of age, ambulation, or corticosteroid treatment. Serum cystatin C was 0.67 ± 0.11 mg/l compared to normal controls 0.69 ± 0.09. mg/l. In these same individuals serum creatinine was severely reduced (0.27 ± 0.12 mg/dl) versus normals (0.75 ± 0.15 mg/dl, P < 0.01). In one DMD subject in renal failure, cystatin C was elevated. This study demonstrates the potential value of cystatin C as a biomarker for monitoring renal function in DMD. Its applicability extends to other neuromuscular diseases. Muscle Nerve, 2009     

A randomized controlled trial of early surgery in duchenne muscular dystrophy

We performed a randomized controlled trial of early surgical treatment of contractures in 20 boys with Duchenne muscular dystrophy, age 4–6 yr. Surgery consisted of release of hip flexors, removal of iliotibial bands, and lengthening of tendo Achilles bilaterally. All patients were monitored for at least 12 months post-randomization, and assessed quantitatively for muscle strength and function. Surgery corrected the deformities, but had no beneficial effect on strength or function. Indeed, data in the second year showed more rapid deterioration of function in some of the operated boys. There appeared to be continued evolution of pathology following surgery, as assessed by sequential muscle ultrasound and muscle biopsy. We cannot recommend this type of surgery as a routine treatment.     

Pericardial effusion with cardiac tamponade as a cardiac manifestation of duchenne muscular dystrophy

Duchenne muscular dystrophy (DMD) is the most common hereditary neuromuscular disease in children. It is an X‐linked hereditary dystrophinopathy due to the absence of dystrophin. Its onset is often in early childhood and presents with proximal distribution of weakness and a progressive course. Cardiac involvement in DMD is common, and its onset is usually after the age of 10 years. The most common cardiac manifestations are a dilated cardiomyopathy and cardiac arrhythmia. However, pericardial effusion with cardiac tamponade is a very rare cardiac complication of DMD. We report a boy with DMD who initially presented with progressive dyspnea and an enlarged cardiac silhouette on chest radiography who subsequently developed a large pericardial effusion with cardiac tamponade. Early recognition of pericardial effusion with cardiac tamponade is important for institution appropriate therapy. Muscle Nerve, 2009     

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.     

Functional evaluation of Duchenne muscular dystrophy: proposal for a protocol

A protocol for the evaluation of functional activities in subjects with Duchenne muscular dystrophy (DMD) was designed. The aim of our study was to define objective clinical criteria for the evaluation both of the clinical status of the patient and of the natural history of the illness itself. A protocol with such criteria is particularly necessary when testing the efficacy of treatment. 43 still-ambulant children with DMD between the ages of 3.10 yr and 10.4 yr were examined. Of this number 19 children were evaluated every 4 months over a period of 12 months; of these 14 formed part of a randomized double blind trial with L-carnitine (1.2–1.8 g/day) versus placebo.This work has been in part supported by a grant from the Dino and Enzo Ferrari Foundation for Muscular Dystrophy Research.     

Correlates of care for young men with duchenne and becker muscular dystrophy

Introduction: In progressive conditions, such as Duchenne and Becker muscular dystrophy (DBMD), the need for care may outpace care use. We examined correlates that contribute to utilization of needed care. Methods: Structured interviews were conducted on use of care among 34 young men with DBMD who were born before 1982. Results: Disease severity, per capita income, and presence of other relatives with DBMD predicted greater use of services. Race/ethnicity, acculturation, and level of caregiver education did not significantly predict service utilization. Conclusions: We identified disparities in receipt of healthcare and related services in adult men with DBMD that can affect quality of life. Despite the high disease severity identified in this population, these men utilized only half of the services available to individuals with significant progressive conditions. Providers should be aware of low service utilization and focus on awareness and assistance to ensure access to available care. Muscle Nerve 49 : 21–25, 2014     

Duchenne型肌营养不良症中神经元型一氧化氮合酶和utrophin的表达水平

目的研究神经元型一氧化氮合酶(n NOS)和抗肌萎缩蛋白相关蛋白(utrophin)在Duchenne型肌营养不良症(DMD)中的表达水平及与病情的关系,并探讨DMD中抗肌萎缩蛋白(dystrophin)、n NOS、utrophin 3者间的相关性。方法收集DMD患者26例,并分为轻症组(19例)和重症组(7例),收集正常对照患者21例,利用免疫荧光方法检测n NOS和utrophin的表达并进行统计分析。结果 DMD患者中23例n NOS呈完全缺失、3例明显减少,22例DMD患者utrophin表达增多,4例患者utrophin阴性表达,正常对照中n NOS均为阳性、utrophin均为阴性,DMD患者n NOS表达减少而utrophin表达增多(Z=-6.557、-5.426,P0.05)。轻症组与重症组比较n NOS、utrophin的表达水平均无统计学意义。相关分析DMD中utrophin与dystrophin的表达水平呈负相关(r=-0.419,P0.05),而n NOS与utrophin、dystrophin均无相关性。结论 DMD患者中n NOS的表达减少、utrophin的表达增多,且两者可能参与DMD的病理过程。     

Health services received by individuals with duchenne/becker muscular dystrophy

Introduction: Anecdotal reports from families and care providers suggest a wide variation in services received by individuals with Duchenne/Becker muscular dystrophy (DBMD). Methods: We documented the type and frequency of health services received by individuals with DBMD using the Muscular Dystrophy Surveillance Tracking and Research Network (MD STARnet) interview data released in June 2012. Interviews with eligible caregivers from 5 sites (Arizona, Colorado, Georgia, Iowa, and western New York) were conducted from April 2007 to March 2012. Results: Two hundred ninety‐six caregivers (66% of those contactable) participated in the interview. There were significant differences among sites in the specialists seen and services received. Concurrence with cardiac recommendations was higher than that with respiratory recommendations. Conclusions: The results of this survey support and quantify the anecdotal reports from families and care providers regarding the disparities in services received by individuals with DBMD. It remains to be determined whether these differences affect outcomes. Muscle Nerve 53: 191–197, 2016