Congenital muscular dystrophy: the importance of early diagnosis and orthopaedic management in the long-term prognosis

Consensus statement on standard of care for congenital muscular dystrophies

Congenital muscular dystrophies are a group of rare neuromuscular disorders with a wide spectrum of clinical phenotypes. Recent advances in understanding the molecular pathogenesis of congenital muscular dystrophy have enabled better diagnosis. However, medical care for patients with congenital muscular dystrophy remains very diverse. Advances in many areas of medical technology have not been adopted in clinical practice. The International Standard of Care Committee for Congenital Muscular Dystrophy was established to identify current care issues, review literature for evidence-based practice, and achieve consensus on care recommendations in 7 areas: diagnosis, neurology, pulmonology, orthopedics/rehabilitation, gastroenterology/ nutrition/speech/oral care, cardiology, and palliative care. To achieve consensus on the care recommendations, 2 separate online surveys were conducted to poll opinions from experts in the field and from congenital muscular dystrophy families. The final consensus was achieved in a 3-day workshop conducted in Brussels, Belgium, in November 2009. This consensus statement describes the care recommendations from this committee.

Avaliação da função motora em crianças com distrofia muscular congênita com deficiência da merosina

A distrofia muscular congênita (DMC) compõe um grupo de miopatias caracterizadas por hipotonia e fraqueza muscular notadas até o primeiro ano de vida. Em torno de 40% a 50% dos casos são decorrentes de deficiência primária da proteína merosina (DM), os quais apresentam um fenótipo mais homogêneo, com grave comprometimento motor e respiratório. Foram avaliadas neste estudo onze crianças com diagnóstico clínico e histológico de DMC-DM, com idade de 3 a 15 anos, através de exame de força muscular ("Medical Research Council"), análise goniométrica, avaliação das habilidades motoras e das atividades de vida diária (AVDs) (indicador de Barthel), com o objetivo de caracterizar as principais limitações funcionais motoras. Os grupos musculares mais comprometidos foram os flexores cervicais, paravertebrais e proximais dos membros. Os grupos musculares dos membros superiores estavam tão comprometidos quanto os dos membros inferiores, enquanto que os extensores encontravam-se mais comprometidos que os flexores. Todas as crianças apresentavam importantes retrações musculares nos quadris, joelhos e cotovelos. Outras deformidades freqüentes foram escoliose e pés eqüino-varo. Nenhuma criança possuía a habilidade motora necessária para engatinhar, ficar de pé ou andar; e todas foram classificadas como dependentes ou semidependentes para a maioria das AVDs estudadas. Nossos achados confirmam o envolvimento difuso e intenso da musculatura esquelética na DMC-DM, acarretando graves limitações funcionais motoras e deformidades músculo-esqueléticas.

[Congenital muscular dystrophy: clinical study of 17 patients]

We concur with the idea that congenital muscular dystrophy (CMD) is a distinct clinical entity, and report 17 patients (2 negroes and 15 whites; 12 M and 5 F; median age 6 years, range 1 to 24 years) with genetic, clinical, laboratorial, electrophysiological and histochemical studies. All our cases have an inheritance compatible with an autosomal recessive pattern. A decrease in fetal movements was reported by 57% of the mothers, generalized hypotonia at birth was present in 82%, limb girdle and neck weakness, absent or decreased deep tendon reflexes, and limb contractures were present in all. Severe muscular wasting was found in 41%. Calf pseudo-hypertrophy was observed in one patient. A patient was severely mentally retarded and another was borderline. During a 30-month follow-up, the muscle weakness of the majority remained essentially unchanged but the degree of motor activity deteriorated and was proportional to the worsening of the limb contractures. Serum CK levels were normal or increased to a maximum of 8 times. The electromyogram was myopathic in 74%, neurogenic in 13% and normal in 13%. CT scans showed a symmetrical white matter hypodensity in the hemispheres in 8 cases. All but 5 patients were operated upon to release the limb contractures and all were submitted to physical therapy. The contractures recurred in 4 patients submitted to surgery and were probably related to the cessation of physical therapy.

Ullrich's congenital atonic sclerotic muscular dystrophy. A case report

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.

A genetic study of the Fukuyama type congenital muscular dystrophy

A genetic study was carried out on 153 families with 186 Fukuyama type congenital progressive muscular dystrophy (FCMD) patients. Consanguineous marriage of parents was found in 41 families (26.80%). Inbreeding coefficients in the patients was 10 times as high as that of the general population. Both sexes were almost equally affected (M:F = 1.1:1.0). No single parent of the patients was affected. Recurrence among siblings was frequent (9 out of 41 siblings in offspring of related parents and 18 out of 110 siblings in offspring of unrelated parents were affected. The segregation ratio was 23.91-27.08% in offspring of related parents, 20.00-22.94% in offspring of unrelated parents, these values being not significantly different from the 25% expected from the assumption of autosomal recessive mode of inheritance. In the sample two twin pairs were included, of which one male isosexual pair was concordant. Sporadic cases were not significantly more numerous than expected. All these data indicate that the disorder is caused by homozygosity of an autosomal recessive gene. Frequency of the gene was estimated to be 5.2-9.7 X 10(-3) and frequency of the patients 6.9-11.9 X 10(-5). Mutation rate was estimated to be 6.9-11.9 X 10(-5).

Congenital muscular dystrophy (CMD) - a collagen formative disease?

Muscle biopsies of 5 patients with congenital muscular dystrophy (CMD) (8 months to 3 years old) were examined by electron microscopy to determine ultrastructural abnormalities of the muscle as well as of the connective tissue cells. Two populations of muscle fibers were observed in each biopsy. Besides muscle fibers with normal or enlarged diameters there were frequently very small muscle cells indicating immaturity. The most interesting findings in each biopsy were myofibroblast-like cells exhibiting active protein synthesis. Large amounts of collagen fibrils with abnormal diameters as well as accumulation of elastic fibrils within the endomysium in CMD suggest abnormalities in collagen synthesis.

A form of congenital muscular dystrophy

Five children, between 2 and 10 years old, 3 boys and 2 girls, two of them siblings, showed mild clinical and morphological congenital muscular dystrophy. Neuromuscular signs and symptoms being present from birth or early infancy, aggravated only insignificantly during the course of the disease. Three patients developed right ventricular hypertrophy after the age of 9 years, of whom 2 died of cardiac failure at the age of 11 years. There was probably no cardiomyopathy; pulmonary hypertension of unclear range or slightly elevated. The EMG showed abnormal but non-specific features. A myopathic fiber diameter spectrum, intrafascicular fat cells and mild endomysial fibrosis as well as insufficient fiber typing and type I predominance were prominent in histopathological findings. Ultrastructurally, abnormal myofibers were present in each biopsy although the fine structural pathology was non-specific. The families of the patients came from a genetic isolate in the North-Eastern region of the Federal Republic of Germany. The first 4 patients were genetically related to each other by several links among their families dated back over the last 3 centuries. The fifth patient came from the same area, but unequivocal familial linkage could not be established. An autosomal recessive mode of inheritance is suggested for this congenital muscular dystrophy.