Maria Bernadete Dutra Resende

Comparison of motor strength and function in patients with Duchenne muscular dystrophy with or without steroid therapy

OBJECTIVE To compare muscle strength (MS) and motor function in patients with Duchenne muscular dystrophy (DMD) receiving steroids for different times against the natural evolution of DMD described by Scott et al. METHOD 90 patients with DMD (aged 5- 12 years), receiving steroids for one to seven years, were evaluated by Medical Research Council Scale (MRC) and Hammersmith motor ability score. The relation between MS and motor abilities measurement from our data and Scotts ones were ascertained statistically. RESULTS The relation between patients age and Hammersmith scores revealed decrease of 0.76 point per year for age against decrease of 2.23 points on Scotts study. The relation between MRC scale and patients age showed decrease of 0.80 point per year of age against decrease of 3.65 points on Scotts study. CONCLUSION In patients with DMD aged five to 12 years the progression of the disease is delayed by steroids and the motor function is less reduced than muscular strength.

Quantification of muscle strength and motor ability in patients with Duchenne muscular dystrophy on steroid therapy

OBJECTIVE An assessment protocol was applied to quantify and describe muscular strength and motor abilities of 32 patients with Duchenne muscular dystrophy (DMD), aged between 5 and 12 years on steroid therapy. METHOD Assessments were made monthly for the first six months and with intervals of two months thereafter until the 14-month end point. The tests employed included: the Medical Research Council (MRC) scale; the Hammersmith motor ability score; maximum weight lift; timed rise from floor and nine-meter walk. RESULTS The results showed that loss of muscular strength and motor abilities were slowed in comparison to that observed in the natural evolution of the disease according to the literature. CONCLUSION We conclude that a swift and objective assessment may be performed using the MRC scale for lower limbs and trunk, the Hammersmith motor ability score, timed nine-meter walk and weight lifts.

Evaluation of muscle strength and motor abilities in children with type II and III spinal muscle atrophy treated with valproic acid.

BackgroundSpinal muscular atrophy (SMA) is an autosomal recessive disorder that affects the motoneurons of the spinal anterior horn, resulting in hypotonia and muscle weakness. The disease is caused by deletion or mutation in the telomeric copy of SMN gene (SMN1) and clinical severity is in part determined by the copy number of the centromeric copy of the SMN gene (SMN2). The SMN2 mRNA lacks exon 7, resulting in a production of lower amounts of the full-length SMN protein. Knowledge of the molecular mechanism of diseases has led to the discovery of drugs capable of increasing SMN protein level through activation of SMN2 gene. One of these drugs is the valproic acid (VPA), a histone deacetylase inhibitor.MethodsTwenty-two patients with type II and III SMA, aged between 2 and 18 years, were treated with VPA and were evaluated five times during a one-year period using the Manual Muscle Test (Medical Research Council scale-MRC), the Hammersmith Functional Motor Scale (HFMS), and the Barthel Index.ResultsAfter 12 months of therapy, the patients did not gain muscle strength. The group of children with SMA type II presented a significant gain in HFMS scores during the treatment. This improvement was not observed in the group of type III patients. The analysis of the HFMS scores during the treatment period in the groups of patients younger and older than 6 years of age did not show any significant result. There was an improvement of the daily activities at the end of the VPA treatment period.ConclusionTreatment of SMA patients with VPA may be a potential alternative to alleviate the progression of the disease.Trial RegistrationClinicalTrials.gov: NCT01033331

Compensatory movements during functional activities in ambulatory children with Duchenne muscular dystrophy

OBJECTIVE During the transitional phase (ambulatory to non-ambulatory), synergies characterize the evolution of Duchenne muscular dystrophy (DMD). This study was performed to describe and quantify compensatory movements while sitting down on/rising from the floor and climbing up/down steps. METHOD Eighty videos (5 children × 4 assessments × 4 tasks) were recorded quarterly in the year prior to gait loss. Compensatory movements from the videos were registered based on the Functional Evaluation Scale for DMD. RESULTS The most frequently observed compensatory movements were upper limb support on lower limbs/floor/handrail during all the tasks and lumbar hyperlordosis, trunk support on handrail, equinus foot, increased base of support, non-alternated descent, and pauses while climbing up/down steps. CONCLUSION Climbing up/down steps showed a higher number of compensatory movements than sitting down on/rising from the floor, which seemed to be lost before climbing up/down steps in ambulatory children with DMD.

Phenotypic and immunohistochemical characterization of sarcoglycanopathies

INTRODUCTION: Limb-girdle muscular dystrophy presents with heterogeneous clinical and molecular features. The primary characteristic of this disorder is proximal muscular weakness with variable age of onset, speed of progression, and intensity of symptoms. Sarcoglycanopathies, which are a subgroup of the limb-girdle muscular dystrophies, are caused by mutations in sarcoglycan genes. Mutations in these genes cause secondary deficiencies in other proteins, due to the instability of the dystrophin-glycoprotein complex. Therefore, determining the etiology of a given sarcoglycanopathy requires costly and occasionally inaccessible molecular methods. OBJECTIVE: The aim of this study was to identify phenotypic differences among limb-girdle muscular dystrophy patients who were grouped according to the immunohistochemical phenotypes for the four sarcoglycans. METHODS: To identify phenotypic differences among patients with different types of sarcoglycanopathies, a questionnaire was used and the muscle strength and range of motion of nine joints in 45 patients recruited from the Department of Neurology – HC-FMUSP (Clinics Hospital of the Faculty of Medicine of the University of São Paulo) were evaluated. The findings obtained from these analyses were compared with the results of the immunohistochemical findings. RESULTS: The patients were divided into the following groups based on the immunohistochemical findings: α-sarcoglycanopathies (16 patients), β-sarcoglycanopathies (1 patient), γ-sarcoglycanopathies (5 patients), and non-sarcoglycanopathies (23 patients). The muscle strength analysis revealed significant differences for both upper and lower limb muscles, particularly the shoulder and hip muscles, as expected. No pattern of joint contractures was found among the four groups analyzed, even within the same family. However, a high frequency of tiptoe gait was observed in patients with α-sarcoglycanopathies, while calf pseudo-hypertrophy was most common in patients with non-sarcoglycanopathies. The α-sarcoglycanopathy patients presented with more severe muscle weakness than did γ-sarcoglycanopathy patients. CONCLUSION: The clinical differences observed in this study, which were associated with the immunohistochemical findings, may help to prioritize the mutational investigation of sarcoglycan genes.

Ullrich congenital muscular dystrophy and bethlem myopathy: clinical and genetic heterogeneity

UNLABELLED Ullrich congenital muscular dystrophy (UCMD), due to mutations in the collagen VI genes, is an autosomal recessive form of CMD, commonly associated with distal joints hyperlaxity and severe course. A mild or moderate involvement can be occasionally observed. OBJECTIVE To evaluate the clinical picture of CMD patients with Ullrich phenotype who presented decreased or absent collagen VI immunoreactivity on muscular biopsy. RESULTS Among 60 patients with CMD, two had no expression of collagen V and their clinical involvement was essentially different: the first (3 years of follow-up) has mild motor difficulty; the second (8 years of follow-up) never acquired walking and depends on ventilatory support. A molecular study, performed by Pan et al. at the Thomas Jefferson University, demonstrated in the first a known mutation of Bethlem myopathy in COL6A1 and in the second the first dominantly acting mutation in UCMD and the first in COL6A1, previously associated only to Bethlem myopathy, with benign course and dominant inheritance. CONCLUSION Bethlem myopathy should be considered in the differential diagnosis of UCMD, even in patients without fingers contractures; overlap between Ullrich and Bethlem phenotypes can be supposed.

Dystrophin-glycoproteins associated in congenital muscular dystrophy: immunohistochemical analysis of 59 Brazilian cases

UNLABELLED The congenital muscular dystrophies (CMD) are heterogeneous muscular diseases with early and dystrophic pattern on muscle biopsy. Many different subtypes have been genetically identified and most phenotypes not yet identified belong to the merosin-positive (MP) CMD subgroup. OBJECTIVE To analyze the immunohistochemical expression of the main proteins of the dystrophin-glycoproteins associated complex in muscle biopsy of patients with different CMD phenotypes, for investigating a possible correlation with clinical and histopathological data. METHOD Fifty-nine patients with CMD had clinical, histopathological and immunohistochemical data evaluated: 32 had MP-CMD, 23 CMD with merosin deficiency (MD-CMD), one Ullrich phenotype and three Walker-Warburg disease. RESULTS Dystrophin and dysferlin were normal in all; among the patients with MD-CMD, merosin deficiency was partial in nine who showed the same clinical severity as those with total deficiency; the reduced expression of alpha-sarcoglycan (SG) and alpha-dystroglycan (DG) showed statistically significant correlation with severe MD-CMD phenotype. CONCLUSION There is a greater relationship between merosin and the former proteins; among MP-CMD patients, no remarkable immunohistochemical/phenotypical correlations were found, although the reduced expression of beta-DG had showed statistically significant correlation with severe phenotype and marked fibrosis on muscular biopsy.

Heterogeneity of classic congenital muscular dystrophy with involvement of the central nervous system: report of five atypical cases.

A heterogeneous group of patients with congenital muscular dystrophy associated with clinical or radiologic central nervous system involvement other than the severe classic form with merosin deficiency, muscle-eye-brain disease, and Walker-Warburg syndrome is described. A probable hereditary or familial occurrence could be suggested in all patients. One merosin-positive patient presented severe motor incapacity and cerebral atrophy without any clinical manifestation of central nervous system involvement. A second patient, also merosin-positive, had moderate motor and mental handicap, and epilepsy with no changes in neuroimaging. A third patient, found to have partial merosin deficiency by muscle biopsy, manifested severe psychomotor retardation and cerebral atrophy with foci of abnormal white-matter signal on magnetic resonance imaging. Finally, two merosin-positive siblings with microcephaly, mental retardation, and an incapacitating progressive neuromuscular course, exhibited cataracts without defects of neuronal migration or brain malformation. This report emphasizes the broad clinical spectrum and heterogeneity of merosin-positive congenital muscular dystrophy with associated central nervous system involvement, and illustrates the importance of further studies on clinical, immunohistochemical, and genetic grounds for identifying new subsets of congenital muscular dystrophy. (J Child Neurol 2000;15:172-178).

Brazilian consensus on Duchenne muscular dystrophy. Part 1: diagnosis, steroid therapy and perspectives

Significant advances in the understanding and management of Duchenne muscular dystrophy (DMD) took place since international guidelines were published in 2010. Our objective was to provide an evidence-based national consensus statement for multidisciplinary care of DMD in Brazil. A combination of the Delphi technique with a systematic review of studies from 2010 to 2016 was employed to classify evidence levels and grade of recommendations. Our recommendations were divided in two parts. We present Part 1 here, where we describe the guideline methodology and overall disease concepts, and also provide recommendations on diagnosis, steroid therapy and new drug treatment perspectives for DMD. The main recommendations: 1) genetic testing in diagnostic suspicious cases should be the first line for diagnostic confirmation; 2) patients diagnosed with DMD should have steroids prescribed; 3) lack of published results for phase 3 clinical trials hinders, for now, the recommendation to use exon skipping or read-through agents.

Hand Function in Muscular Dystrophies: Relationship Between Performance of Upper Limb and Jebsen–Taylor Tests

The aim of this study was to investigate the relationship between Performance of Upper Limb (PUL) and Jebsen–Taylor Test (JTT) to assess and monitor upper limb function progression in patients with muscular dystrophy. Thirty patients diagnosed with Duchenne muscular dystrophy, limb-girdle muscular dystrophy, Becker muscular dystrophy, myotonic dystrophy Type 1, and fascioscapulohumeral dystrophy were submitted to the shoulder, elbow, and wrist domains of PUL, and to JTT subtests. Spearman tests investigated the relationships between PUL and JTT total scores and domains. Correlations were classified as strong (r ≥ 0.70), moderate (0.40 ≤ r < 0.70), or weak (r ≤ 0.40). There were strong correlations between the PUL and JTT total scores (r = −0.706). Although JTT measures time and PUL provides kinesiologic scores, these measures were related. Therefore, muscle synergies, which control the compensatory movements and motor functions involving mainly shoulder, elbow, wrist, and finger movements, are related to timed performance in patients with muscular dystrophies.