Dystrophy Type Research Articles

Managing Chronic Health Needs in Child Care and Schools—Muscular Dystrophy

Patient Education| 2021 Managing Chronic Health Needs in Child Care and Schools—Muscular Dystrophy Views Icon Views Article contents Figures & tables Video Audio Supplementary Data Share Icon Share Facebook Twitter LinkedIn Tools Icon Tools Get Permissions Cite Icon Cite Search Site Citation Managing Chronic Health Needs in Child Care and Schools—Muscular Dystrophy. Pediatric Patient Education 2021; 10.1542/ppe_document126 Download citation file: Ris (Zotero) Reference Manager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search nav search search input Search input auto suggest search filter All AAP SitesAll PublicationsPediatric Patient Education Search Advanced Search Subjects: Managing Chronic Health Needs in Child Care Muscular dystrophy is a group of genetic diseases that cause muscle wasting and weakness. The most common type is Duchenne muscular dystrophy, which is progressive and occurs only in boys. Duchenne muscular dystrophy occurs in 1 in 3,500 boys at birth. Females may be carriers. Myotonic dystrophy occurs at 1 in 8,000 of all births. Other types of muscular dystrophy are less common. The symptoms of Duchenne muscular dystrophy often start in the preschool age range, that is, 2 to 4 years of age. Symptoms might include being unable to get to standing from sitting and not being able to run. Children with this muscular dystrophy develop swayback, with their stomachs pushed forward, and walk on their toes. They can get leg and calf cramps and can appear clumsy. About a third of boys with Duchenne muscular dystrophy have intellectual disability;... © 2019 American Academy of Pediatrics. All rights reserved. You do not currently have access to this content.

Corneal dystrophies: A decade of experience in a reference center in Bogotá, Colombia

Purpose: To describe sociodemographic findings, frequency, and clinical characteristics of patients with corneal dystrophy who consulted an ophthalmologic national reference center in Bogotá-Colombia in 10 years.Methods: Observational, descriptive case series study was carried out. The information was obtained from reviewing medical records of patients who consulted the cornea service at an ophthalmologic national reference center in Bogotá-Colombia between 2008 and 2018. The diagnosis of corneal dystrophy was done according to the International Committee for Corneal Dystrophies classification, as well as the currently accepted specific name of the dystrophy. The type of dystrophy, clinical, diagnostic findings, sociodemographic characteristics, and type of treatment were evaluated.Results: A total of 151 eyes of 79 patients were analyzed; 68.3% of subjects were female. The mean age was 57.6 ± 18.9 years, with a range between 2 and 95 years. The median best-corrected visual acuity (BCVA) in all the groups at diagnosis was 0.30 LogMAR (interquartile range 0.5) or 20/40 Snellen. Lattice dystrophy type 1 and its variants had the worse BCVA. Fuchs' dystrophy (FD) was the most frequently identified. Regarding treatment, 80.1% (n = 121) did not require any, and 11.9% (n = 18) had a corneal transplant. Thirteen underwent penetrating keratoplasty. Of those, two had a clinical diagnosis of TGFB1 dystrophy, three of stromal dystrophy, and eight of endothelial dystrophy. DSAEK was performed in 5 eyes four had endothelial dystrophy and one had unclassified dystrophy.Conclusions: Adults and females were the most affected groups. FD was the most frequent and unclassified dystrophies were the second most frequently diagnosed. This highlights the importance of complementary studies such as optical coherence tomography of the anterior segment and genetic markers which are not currently universally available in our healthcare system.Ethical considerations: This study was approved by the Institutional Ethics Committee and was conducted in accordance with the principles of the Declaration of Helsinki.

Identification of a novel missense c.386G > A variant in a boy with the POMGNT1-related muscular dystrophy-dystroglycanopathy.

Muscular dystrophy-dystroglycanopathies are autosomal recessive neurologic disorders, caused by homozygous or compound heterozygous mutations in the POMGNT1 gene-encoding protein O-mannose beta-1,2-N-acetylglucosaminyl transferase. This type of muscular dystrophy is characterized by early-onset muscle weakness, gait ataxia, microcephaly, and developmental delay.We performed whole-exome sequencing to detect the disease-causing variants in a 4year-old boy. Afterwards, Sanger sequencing was performed to confirm the detected variant in the patient and his family. We evaluated a 4year-old Iranian boy presented with delayed speech and language development, gait ataxia, global developmental delay, motor delay, neurodevelopmental delay, postnatal microcephaly and strabismus. His parents were first cousins, and the mother had a history of spontaneous abortion. In this study, we report a novel missense c.386G > A; p.(Arg129Gln) variant in the POMGNT1 gene which was confirmed by Sanger sequencing in the patient and segregated with the disease in the family.

Duchenne's Muscular Dystrophy: The Role of Induced Pluripotent Stem Cells and Genomic Editing on Muscle Regeneration.

There are two types of well-known muscular dystrophies: Duchenne's muscular dystrophy (DMD) and Becker's muscular dystrophy. This article focuses on the X-linked recessive disorder of Duchenne's muscular dystrophy, which primarily affects children at age four, with a shortened life span of up to 40 years. A defective dystrophin protein lacking the gene dystrophin is the primary cause of the disease pathophysiology. This defect causes cardiac and skeletal muscle down-regulation of dystrophin, leading to weak and fibrotic muscles. The disease is currently untreatable, so most kids die due to cardiac failure in their late 30's.This review presents current treatment options, based on previous studies conducted over the last five years. We used the PubMed database to analyze and review the most important investigations. We also included an analysis of induced pluripotent stem cell therapy vs. genetic therapy using the mdx mouse model. We have discovered promising results on mdx mouse models to date and excited about the potential for where further clinical human trials can go.

Genetics of Muscle Stiffness, Muscle Elasticity and Explosive Strength.

Muscle stiffness, muscle elasticity and explosive strength are the main components of athletes’ performance and they show a sex-based as well as ethnicity variation. Muscle stiffness is thought to be one of the risk factors associated with sports injuries and is less common in females than in males. These observations may be explained by circulating levels of sex hormones and their specific receptors. It has been shown that higher levels of estrogen are associated with lower muscle stiffness responsible for suppression of collagen synthesis. It is thought that these properties, at least in part, depend on genetic factors. Particularly, the gene encoding estrogen receptor 1 (ESR1) is one of the candidates that may be associated with muscle stiffness. Muscle elasticity increases with aging and there is evidence suggesting that titin (encoded by the TTN gene), a protein that is expressed in cardiac and skeletal muscles, is one of the factors responsible for elastic properties of the muscles. Mutations in the TTN gene result in some types of muscular dystrophy or cardiomyopathy. In this context, TTN may be regarded as a promising candidate for studying the elastic properties of muscles in athletes. The physiological background of explosive strength depends not only on the muscle architecture and muscle fiber composition, but also on the central nervous system and functionality of neuromuscular units. These properties are, at least partly, genetically determined. In this context, the ACTN3 gene code for α-actinin 3 has been widely researched.

Clinical and genetic characteristics of congenital muscular dystrophies (part 2)

Dystroglycanopathy is one of the groups of congenital muscular dystrophies, the occurrence of which is associated with a disorder of α-dystroglycan glycosylation. To date, 18 genes responsible for the development of this condition are known. The 2nd part of this review presents the classification, phenotypic forms, clinical features, pathogenesis and etiology of this type of congenital muscular dystrophies. In addition, the issues of molecular diagnosis of congenital muscular dystrophies are considered and information on modern developments in the treatment of this pathology is provided.

Characteristic muscle signatures assessed by quantitative MRI in patients with Bethlem myopathy.

Using MRI, the main aim was to (1) map the pattern of muscle involvement by assessing fat fraction and (2) investigate frequency of target and sandwich signs in 42 muscles of patients with Bethlem myopathy (BM). Fifteen BM patients were included. Results were compared to findings in 8 healthy controls and 50 patients with four other types of muscular dystrophies. All muscles, except one, showed higher fat fraction in BM patients vs healthy controls (p < 0.05) with an overall proximal muscle affection, resembling a limb girdle-like pattern. In moderate patients, the specificity was 90% for the sandwich sign and 98% for the target sign. Sensitivity for both signs was 100%. Twelve BM patients had sandwich sign in other muscles than the vastus lateralis. Muscle strength correlated with fat fraction. Mean fat fraction in the psoas major was 39% in BM patients, which was considerably higher than in 3 of the 4 muscular dystrophy control diseases. The presence of signs in conjunction with severe affection of the psoas major muscle can serve as a diagnostic tool in BM. The high level of STIR lesions in muscles of BM patients warrants further investigations.

Non-alcoholic fatty liver disease in children: relationship with the main components of metabolic syndrome in children

There is a high frequency of combination of components of metabolic syndrome (MS) and liver damage in obese patients.Of interest is the study of clinical and pathogenetic relationships between the morphofunctional state of the liver and the development of MS in children.Objective: to Study the functional state of the liver in children with MS and to assess the relationship with its main components.Materials and methods. 483 obese children (SDS BMI≥2.0) aged from 5 to 16 years (285 boys and 198 girls) were examined: I gr. — 237 children with MS, II gr. — 246 obese children without MS. Comprehensive examination included anamnesis, anthropometry, clinical and biochemical blood tests, lipid spectrum and carbohydrate metabolism, ultrasound examination of the abdominal cavity and retroperitoneal space, CT of the abdominal cavity. Statistical processing of the results was carried out using the package «STATISTIKA 6.0».Research result. Ultrasound-signs of nonalcoholic fatty liver disease (NAFD) in I gr. revealed significantly more often than in II gr. (166 — 70% and 125 — 51%, respectively, p&lt;0.05). The majority (91%) of children with NAFD are 10–16 years old. Boys slightly more than girls (58% and 42%). The increase of ALT in the I gr. it was registered at 27% of children, in II gr. — in 18% of children (p&lt;0.05). Increase of ALT in boys was detected 2 times more often than in girls (26% and 13%, p&lt;0.05). In patients with NAFLD, regardless of the group, signs of atherogenic dyslipidemia (increased triglycerides, decreased HDL), impaired carbohydrate metabolism (insulin, C‑peptide and IR index) were more often diagnosed. A higher frequency of hyperglycemia in children I gr. was established. regardless of the liver condition (68% of children without NAFLD and 69% of children with NAFLD), whereas in II gr. it was registered more often in the presence of NAFLD (16% and 8%). In both groups, the level of MC in children with NAFLD was higher than without it, and in I gr. this indicator was significantly higher than in children of II gr. Mean fibrinogen levels were also higher in children with NAFLD, and these differences were significantly significant in I gr.Conclusion.1. Ultrasound criteria for NAFLD in children with MS are diagnosed significantly more often (70%) than in children with uncomplicated obesity (51%).2. CT-changes in liver parenchymain NAFLD are characterized by the presence of diffuse focal process with the presence of different sites with changes in the type of fatty dystrophy and steatohepatitis against the background of unchanged parenchyma.3. Adolescents over 12 years of age and males predominate among children with NAFLD.4. Waist circumference in children with NAFLD, regardless of the group, significantly exceeds that of children without it, which indicates the relationship of functional disorders of the liver with the development of abdominal typeof obesity — the main component of MS.5. Hyperfermentemia in the form of increased ALT levels is most often registered in children with MS in the presence of NAFLD (27%), in 15% of them the values exceed the normative indicators by 1.5 or more times, which indicates a high risk of developing an inflammatory process of the type of steatohepatitis.6. Lipid metabolism disorders in the form of an increase in TG and a decrease in HDL in children with NAFLD are recorded more often than in children without it, regardless of the presence of MS, but their combination is diagnosed exclusively in children with MS: in children with NAFLD — in 29% of cases, without it — in 23%.7. Regardless of the group, changes in carbohydrate metabolism in the presence of NAFLD were more pronounced than in children without it, while children with MS and NAFLD showed a more significant increase in glycemia, insulin and IR index.8. Children with MS and NAFLD have a higher incidence of purine metabolism disorders.9. A correlation between hepatic metabolism and disorders in the fibrinolysis system, which progress with the duration of the disease, was obtained.

Psychosocial impact of sport activity in neuromuscular disorders.

Previous studies demonstrated the benefits of motor exercise and physical activity in neuromuscular disorders. However, very few papers assessed the effects of sport practise. The aim of this multicentre study was to assess the impact of sport activity on self-esteem and emotional regulation in a cohort of athletes with neuromuscular disorders. The 38 patients with Duchenne, Becker or other types of muscular dystrophy or spinal muscular atrophy practising sport (aged 13-49years) and 39 age-, gender-, disability- and disease-matched patients not practising sport were enrolled. Testing procedures to assess self-esteem, anxiety and depression disorder, personality trait and quality of life (QoL) were used. Patients practising sport had a significantly higher self-esteem, lower level of depression, greater social own identity and adherence and QoL. Frequency of sport activity may represent a complementary therapy in neuromuscular disorders to improve mental and social well-being.

МІКРОСКОПІЧНА БУДОВА ОРГАНІВ КУРЧАТ- БРОЙЛЕРІВ ЗА ЗБАГАЧЕННЯ РАЦІОНУ КОМПЛЕКСОМ НАНОМІКРОЕЛЕМЕНТІВ (Zn, Cu, Ag, Co, He, Mg)

&#x0D; &#x0D; &#x0D; &#x0D; The work is devoted to the study of the microscopic structure of broiler chickens organs for the enrichment of the diet with a complex of nano trace elements which include the citrates of nano Zn, Cu, Ag, Co, He, Mg. It was found that the use of a complex of nano-micronutrients, at a dose of 1 cm3/dm3 of drinking water in the drinking mode for five days in a row after five days, did not cause pathomorphological changes in the internal organs and skeletal muscles of slaughtered broiler chickens.The use in the diet of the experimental bird complex of nano trace elements at a dose of 10 and 20 cm3/dm3 drinking water can lead to structural disorders in the liver, kidneys and spleen in the form of local circulatory disorders, necrosis of cells of the parenchyma of organs. Extracapillary glomerulonephritis and necrotic- dystrophic changes in the epithelium of the tubules are recorded in the kidneys (proteinaceous nephrosis by type of granular dystrophy, in some cases necrotic nephrosis); In internal organs there are local circulatory disorders (congestive hyperemia, stasis, etc.). In cells of parenchyma of organs destruction of organelles, cell membranes is registered, that causes at first development of dystrophic processes on decompositive type, and subsequently - death of cells.&#x0D; &#x0D; &#x0D; &#x0D;

TMEM16E/ANO5 mutations related to bone dysplasia or muscular dystrophy cause opposite effects on lipid scrambling.

Mutations in the human TMEM16E/ANO5 gene are causative for gnathodiaphyseal dysplasia (GDD), a rare bone malformation and fragility disorder, and for two types of muscular dystrophy (MD). Previous studies have demonstrated that TMEM16E/ANO5 is a Ca2+ -activated phospholipid scramblase and that the mutation c.1538C>T (p.Thr513Ile) causing GDD leads to a gain-of-function phenotype. Here, using established HEK293-based functional assays, we investigated the effects of MD-related and further GDD-related amino acid exchanges on TMEM16E/ANO5 function in the same expression system. These experiments also revealed that the gradual changes in HEK293 cell morphology observed upon expression of TMEM16E/ANO5GDD mutants are a consequence of aberrant protein activity. Our results collectively demonstrate that, on the level of protein function, MD mutations are associated to loss-of-function and GDD mutations to gain-of-function phenotypes, confirming conjectures made on the basis of inheritance modes.

Skeletal muscle in health and disease.

ABSTRACTSkeletal muscle fibres are multinucleated cells that contain postmitotic nuclei (i.e. they are no longer able to divide) and perform muscle contraction. They are formed by fusion of muscle precursor cells, and grow into elongating myofibres by the addition of further precursor cells, called satellite cells, which are also responsible for regeneration following injury. Skeletal muscle regeneration occurs in most muscular dystrophies in response to necrosis of muscle fibres. However, the complex environment within dystrophic skeletal muscle, which includes inflammatory cells, fibroblasts and fibro-adipogenic cells, together with the genetic background of the in vivo model and the muscle being studied, complicates the interpretation of laboratory studies on muscular dystrophies. Many genes are expressed in satellite cells and in other tissues, which makes it difficult to determine the molecular cause of various types of muscular dystrophies. Here, and in the accompanying poster, we discuss our current knowledge of the cellular mechanisms that govern the growth and regeneration of skeletal muscle, and highlight the defects in satellite cell function that give rise to muscular dystrophies.

Hereditary neuromuscular diseases. Part 1. Muscular dystrophies: dystrophinopathy emerinopathy and facio-scapulo-humeral forms

Written of history of the description of myopathies, modem classification of muscular dystrophies, clinical-genetic peculiarities of basic types of muscular dystrophies (dystrophinopathy, emerinopathy, facio-scapulo-limb type, limb-girdle types, distal types, ocylopharingeal and oculopharingodistal) and their diagnostic, pathogenesis and methods of treatment.

Disability and quality of life in individuals with muscular dystrophy

In the county of Orebro, Sweden, 32 individuals with myotonic disorders and 25 with other types of muscular dystrophy were examined. Disability was assessed with functional tests and standardized observations of muscle function (mainly based on those proposed by Dr. Brooke), a new self-administered questionnaire regarding the Activities of Daily Living (ADL) and the ADL staircase (based on Katz ADL index). The results of the different tests of disability were highly correlated. The Sickness Impact Profile and the Kaasa test were used for assessing the quality of life, and no significant differences were found between the groups of muscular dystrophy. In an explanatory factor analysis three main factors of disability were found. The factors walk and move" and "finger function" were fair to good associated with the quality of life. This study offers an approach for research on the consequences of muscular dystrophy using established as well as new methods."

Microscopic changes in the digestive organs of domestic canaries poisoned with canthaxanthin

Intoxication of canaries with canthaxanthin has been recorded more and more often since the late 1990s. This problem is related to active use of this substance for changing or increasing the colouration of this species of bird. For determining morphological changes during canthaxanthin toxicosis, we formed one control and three experimental groups of domestic canaries, which were given canthaxanthin in different doses. The material for microscopic surveys was isolated from the digestive organs of the examined birds; from this material, histological sections were prepared and stained with hematoxylin and eosin. According to the results of microscopic analysis, we determined that the intoxication of the organism of canaries with canthaxanthin causes a certain complex of changes at the tissue level. We found that canthaxanthin intoxication leads to chronic pathological processes in the digestive organs, both the digestive canal and digestive glands (pancreas, liver). In the organs of the digestive tract (glandular stomach or proventriculus, muscular stomach or gizzard, and the intestine) we found chronic catarrhal inflammation, and also proliferative processes – cellular infiltration of the stroma, overgrowth of the connective tissue. In some cases we also found distrophic processes such as keratinization of the epithelium of the mucous membrane of the glandular stomach. In the pancreas, except for edema of the stroma, no pathological processes were observed. In the liver, we found different types of dystrophy – protein (granular, hydropic) and fatty (infiltrational). With introduction of the highest doses of canthaxanthin used in the experiment, we determined a tendency towards exacerbation of pathological processes, because, apart from the already mentioned changes, we recorded manifestations of alteration (necrotic processes, disorders in blood circulation). Therefore, we proved that irrational use of canthaxanthin in canary-keeping is a factor that can negatively influence the health of these animals. Using the data we obtained, use of canthaxanthin in the diet of canaries can be correlated with their diet, thus avoiding risk of bird diseases. There is scope for further studies on the impact of canthaxanthin on other organs and the systems of the organs at microscopic level, as well as conducting biochemical and morphological analyses of blood, which would allow the creation of a new complete clinical-anatomical description of this pathology.

Structural and functional mechanisms of reactive changes in vasoconstrictors, internal organs and skin with metabolic syndrome and toxic action of doxorubicin

A comparative analysis of structural organization changes in skin microcirculatory vessels, serum level of leptin, diponectin, resistin in the ase of metabolic syndrome and doxorubicin intoxication was performed. It was shown that hypertrophy of the muscle fibers, perivascular space edema, and skin arteriole spasm in the metabolic syndrome accompanied by a structural reorganization of the organs and their vessels by the type of dystrophy. In the case of doxorubicin intoxication, the alteration processes were dominant. Changes in the level of hormones leptin adiponectin and resistin in the metabolic syndrome and doxorubicin intoxication were multidirectional.

Outcomes of Heart Failure in Adult Patients with Muscular Dystrophy: A Single Center Experience

Introduction Cardiomyopathies associated with Duchenne (DMD) or Becker (BMD) muscular dystrophy have been historically noted to have poor outcomes in the pediatric population, but studies in the adult population are sparse. Hypothesis: The goal of this study was to determine the rates of ejection fraction (EF) decline and overall survival outcomes in a cohort of adult patients with dystrophinopathic cardiomyopathies on contemporary heart failure therapies. Methods This is a retrospective cohort study of 41 adults with muscular dystrophy (29 with DMD, 7 with BMD, 5 with other types of muscular dystrophy) out of 1582 heart failure patients followed in the Loma Linda University International Heart Institute clinic who were evaluated using the following outcome measures: mortality and rate of EF decline comparing first and most recent echocardiogram. Results The cohort had a mean age of 32 years (DMD was 31 and BMD was 35 years), 71% with DMD, 17% with BMD, 100% male, 44% Caucasian, 37% Hispanic, and 12% African American. Mean follow up time in clinic was 6.79 years. Mortality within 5 years was 29% (17% in the DMD group and 33% in the BMD group). Mean EF on the most recent echocardiogram was 31.7% for the DMD group and 28.0% for the BMD group. Of the patients who are still alive (n=29), 83% are on a beta blocker and 93% are on an ACEi, ARB, or ARNI. Of those who have died (n=12), 92% were on a beta blocker and 75% were on ACEi, ARB, or ARNI. Twelve out of 31 survivors were on ivabradine versus 0 out of 12 who died (p=0.08). The mean rate of EF decline in the overall cohort was about 3.1% per year (3.0% per year for DMD, 4.4% year for BMD); see Figure 1. The mean rate of EF decline in those who died was 3.7% per year, and 2.8% in those who are still alive. Conclusions Dystrophinopathic cardiomyopathies are associated with progressive left ventricular remodeling and about 3% per year mean drop in EF. Survival tended to be greater in patients treated with ivabradine. Further research is needed in the adult muscular dystrophy population to evaluate the effectiveness of contemporary heart failure therapy including ivabradine in slowing the progression of their cardiomyopathy

Vertex expands CRISPR programs

Vertex Pharmaceuticals is gearing up to tackle two types of muscular dystrophy with CRISPR gene-editing therapies. The Boston-based drug company will acquire the gene-editing start-up Exonics Therapeutics for $245 million and will pay Crispr Therapeutics $175 million to expand an existing collaboration. In addition to the up-front payments, Exonics and Crispr Therapeutics each could earn $1 billion in milestone payments. Vertex will also launch a genetic therapies research site to conduct preclinical studies and manufacture CRISPR therapies for its clinical programs. The news builds on announcements Vertex made in January to collaborate with the gene-editing start-up Arbor Biotechnologies on gene-editing systems that could be used for therapies. That month, Vertex also licensed two compounds from Merck KGaA that inhibit the DNA damage response, which Vertex believes may help boost the effectiveness of gene editing. Vertex began collaborating with Crispr Therapeutics in 2015 to develop permanent treatments...

Extension Study to Evaluate the Long-Term Effects of ACE-083 in Patients With Facioscapulohumeral Muscular Dystrophy (FSHD) and Charcot-Marie Tooth (CMT) Disease Types 1 and X (CMT1 and CMTX)

Extension Study to Evaluate the Long-Term Effects of ACE-083 in Patients With Facioscapulohumeral Muscular Dystrophy (FSHD) and Charcot-Marie Tooth (CMT) Disease Types 1 and X (CMT1 and CMTX)

Motor clinical progression in a series of pediatric Duchenne and Becker muscular dystrophy cases

Muscular dystrophy is a neuromuscular disorder that begins with muscle weakness and impaired motor function. Duchenne muscular dystrophy (DMD) is more severe and destructive than Becker muscular dystrophy (BMD), and both are progressive in nature. These 2 types of muscular dystrophy are caused by mutations in related to X-chromosome genes.1 The mutations that occur in DMD are nonsense mutations. Deletion is present in 60% of DMD cases, while duplication occurs in 10% of DMD cases, resulting in loss of dystrophin protein. Mutations in BMD are missense mutations, so dystrophin is still formed, but in decreased amounts and quality.2,3&#x0D; The prevalence of DMD was reported to be three times greater than that of BMD, with a prevalence of 1.02 per 10,000 male births vs. 0.36 per 10,000 male infants, respectiveley.4 Anatomical pathology examination revealed loss of dystrophin in the examination of muscle biopsy without the presence of evidence leading to other neuromuscular diseases. Clinical DMD symptoms begin to appear at the age of 2-4 years. The child is observed to fall often and has difficulty climbing stairs. Muscle weakness worsens, especially in the upper limbs, continuing with heart and respiratory problems. The main causes of death in DMD are respiratory failure and heart failure.5 The BMD has varied clinical symptoms, beginning with the appearance of myalgia, muscle cramps, and arm weakness progressing towards myopathy. Some patients are asymptomatic until the age of 15, but 50% of patients show symptoms at age 10, and almost all by age 20.6