Duchenne Muscular Dystrophy (DMD)

Emergency Management

Diagnosis and management of Duchenne muscular dystrophy, part 3: primary care, emergency management, psychosocial care, and transitions of care across the lifespan covers key issues related to the emergency care of patients with DMD, and is intended to be a useful guide for emergency medicine providers, primary care clinicians, and neuromuscular specialists; and a resource for patients, who can take this guide with them when they seek emergency care.

This care consideration is part of a three-part update of the 2010 DMD care considerations and was published in 2018 by a steering committee of experts from a wide range of disciplines.

Clinical Care Guidelines

Best Practice Guidelines on molecular diagnostics in Duchenne/Becker muscular dystrophies – Neuromuscular Disorders were established by 29 senior scientists from Europe, the USA, India and Australia, and published in 2010.

Development of clinical practice guidelines for allied health and nursing assessment and management of Duchenne muscular dystrophy was done through consultations with health professionals and consumer advocacy groups to provide evidence-based guidance in Australia and New Zealand; and published in 2021.

The following 3-part international Duchenne muscular dystrophy (DMD) clinical care considerations is an update of the 2010 DMD care considerations:

• Diagnosis and management of Duchenne muscular dystrophy, part 1: diagnosis, and neuromuscular, rehabilitation, endocrine, and gastrointestinal and nutritional management
• Diagnosis and management of Duchenne muscular dystrophy, part 2: respiratory, cardiac, bone health, and orthopaedic management
• Diagnosis and management of Duchenne muscular dystrophy, part 3: primary care, emergency management, psychosocial care, and transitions of care across the lifespan

Adult North Star Network (ANSN): Consensus guideline for the standard of care of adults with Duchenne muscular dystrophy is aimed to be a framework to improve clinical services and multi-disciplinary care for adults with DMD in the UK; published in 2021

Synonyms

Severe dystrophinopathy, Duchenne type

Personal Stories

Duchenne muscular dystrophy (DMD) varies between individuals, and each person’s experience is unique.

Please visit Save Our Sons Duchenne Foundation: Meet Our Heroes to read the personal stories of people living with DMD.

Symptoms

Duchenne muscular dystrophy (DMD) typically presents during early childhood, with delays in developmental milestones, such as walking independently and learning to talk.³ The symptoms worsen over time as the disease progresses. Children may start to walk with a waddling gait, have frequent falls, and have difficulty climbing stairs or getting up from a sitting or lying down (supine) position (Gower’s sign).⁵ They eventually progress to requiring the use of a wheelchair.^1,3,6 Some individuals, but not all, may be impacted by learning difficulties.

As the disease progresses, the muscles relating to the heart (cardiac) and breathing (respiratory) tend to become affected. Individuals with DMD may develop life-threatening complications involving the heart muscle (cardiomyopathy) and decreased respiratory function by their late teens or early twenties.^1,3,6

Please speak to your medical team to learn more about the symptoms and complications of DMD.

Cause/Inheritance

Duchenne muscular dystrophy (DMD) and Becker muscular dystrophy (BMD) are both genetic conditions caused by genetic changes in the DMD gene on the X chromosome.^1,6 These genetic changes include single base changes (sequence variants/ a single letter changes in the genetic code), deletions, duplications, insertions and other changes.¹ For more information on different types of genetic changes, please refer to Centre for Genetics Education: Types of genetic variation.

The DMD gene is a very large gene responsible for making the dystrophin protein that is important for muscle stability, function and strength. In Duchenne muscular dystrophy (DMD), the genetic changes result in no normal (functional) dystrophin protein being made, whilst in BMD, there is still dystrophin protein but at lower amounts than normal or is only partially functional.^1,3

These genetic changes may be inherited from parents in a X-linked recessive manner or may occur randomly in the individual (de novo mutation).⁴ These conditions are more common in males,^1,6 as males who only have one X chromosome will have one copy (allele) of the DMD gene, hence a genetic change in that copy is enough to cause DMD or BMD. Females have two X chromosomes and two copies of the DMD gene – in most cases, genetic changes have to occur in both copies to cause the condition, however in some cases changes in one copy is enough to result in some symptoms.⁶ Females with changes in one copy are called “carriers” and can pass on the genetic change to their children whether they have symptoms or not (asymptomatic).

Further information about X-linked recessive inheritance can be found at Centre for Genetics Education: X-linked Recessive Inheritance Factsheet.

If you would like to learn more about the inheritance and impact of this condition, please ask your doctor for a referral to a genetic counsellor. Genetic counsellors are qualified allied health professionals who can provide information and support regarding genetic conditions and testing. More information about genetic counselling can be found at:

• Information on Genetic Services
• The National and State Services pages underneath the ‘Genetic Counselling’ sections listed

Diagnosis

Diagnosis of Duchenne muscular dystrophy (DMD) may involve clinical examination of symptoms, blood tests to look for increased levels of creatine kinase (CK) enzyme, and genetic testing to look for genetic changes in the DMD gene.^5,7 If the results of the genetic tests are unclear (inconclusive), a muscle biopsy may be recommended to look for dystrophin in the muscle.⁷

Differential diagnosis (to rule out other conditions) includes severe Becker muscular dystrophy and limb girdle muscular dystrophy.⁵

Treatment

There is no overall curative treatment for Duchenne muscular dystrophy (DMD), but there is extensive research underway to develop therapies.¹ Treatment for DMD currently involves strategies to manage symptoms, slow progression of the disease and reduce the risk of life-threatening complications.^2,7 This involves a multidisciplinary team, and may include:^3,5,7

• use of corticosteroids to slow down disease progression
• physiotherapy to build muscle strength and prevent shortening of muscles (contractures)
• monitoring for development of scoliosis (sideways curvature of the spine)
• regular monitoring of heart and breathing (respiratory) function

Information on relevant mobility equipment and other assistive technology can be found at The Loop – Your Neuromuscular Resource Hub: Equipment.

It is best to speak with your medical team to learn more about suitable management strategies for DMD. Treatment will depend on an individual’s specific symptoms and complications.

Clinical Care

Healthcare professionals involved in the treatment of Duchenne muscular dystrophy (DMD) may include general practitioners (GP), paediatricians, geneticists, neurologists, neuromuscular nurses, cardiologists, respiratory physicians, endocrinologists, physiotherapists, occupational therapists, orthotists, speech therapists, social workers, and dieticians.^1-3 The need for different healthcare professionals may change over a person’s lifetime and extend beyond those listed here.

Research and Data

The Australian Neuromuscular Disease Registry is an Australia-wide registry that collects information about individuals with certain neuromuscular conditions, including Duchenne muscular dystrophy (DMD). The registry collects important medical information from adult and child patients across the country to improve the understanding of neuromuscular disease and accelerate the development of new therapies.

Please visit Australian Clinical Trials to learn about clinical trials for DMD in Australia; there may not be any clinical trials currently available.

Information regarding clinical trials for DMD in other countries can be found at ClinicalTrials.gov; there may not be any clinical trials currently available.

It is best to discuss your interest in any clinical trials with your medical team to determine suitability and eligibility.

Rare Disease Organisation(s)

Duchenne AustraliaRVA Partner Australian Organisation
Website: https://www.duchenneaustralia.org/
Contact form: https://www.duchenneaustralia.org/contact

Duchenne Australia strives for all Australians living with Duchenne and associated dystrophinopathies, to have access to evidence-based care, and the best possible quality of life, through advocacy for emerging therapies, research and clinical trials.

Save Our Sons Duchenne Foundation RVA Partner Australian Organisation
Website: https://saveoursons.org.au/
Contact form: https://saveoursons.org.au/pages/contact-us

Save Our Sons Duchenne Foundation was founded in 2008 and is the peak body for those living with Duchenne and Becker muscular dystrophy (around 1,000 young people) across Australia.  Save Our Sons Duchenne Foundation’s vision is to find a cure for Duchenne and Becker muscular dystrophy whilst actively working to ensure enhanced quality of life (including quality of educational opportunities) for those young people and their families affected by this condition.

Please note that RVA does not necessarily monitor or endorse each group/organisation’s operational governance.

Support Services/Resources

Save Our Sons Duchenne Foundation: Resources page includes free, useful resources such as:

• Emergency information card for parents of boys and rare girls with Duchenne
• Information booklet for the newly diagnosed
• A guide for NDIS planning (Duchenne & Becker Muscular Dystrophy)
• Teachers Resource on Duchenne muscular dystrophy (DMD)

Duchenne Australia: Glossary provides definitions for medical terms relevant to DMD.

For information on available government and social services that provide support for individuals with a rare disease, please visit the National and State Services pages.

Mental Health

People living with a rare disease, including families and carers, often face unique challenges such as diagnostic delays, misdiagnoses, limited treatment options, and limited access to rare disease specialists and support. These challenges may impact people’s emotional wellbeing and quality of life. Many people find it helpful to seek mental health and wellbeing support to cope with ongoing stress and uncertainty. Connecting with people who have shared experiences through a support group may also be helpful.

Information about relevant mental health and wellbeing support can be found at:

• RARE Portal: Mental Health and Wellbeing Support for Australians Living with a Rare Disease
• The National and State Services pages underneath the ‘Mental Health’ sections listed

Other

Further information on Duchenne muscular dystrophy (DMD) can be found at:

• healthdirect: Duchenne muscular dystrophy
• The Loop – Your Neuromuscular Resource Hub: Duchenne Muscular Dystrophy (DMD)
• RARE Portal: Muscular Dystrophy (Group of Conditions)
• Genetic and Rare Diseases (GARD) Information Center: Duchenne muscular dystrophy
• National Organization for Rare Disorders (NORD): Duchenne Muscular Dystrophy
• TREAT-NMD: DMD Care (for Patients) – a comprehensive Duchenne guide for families based on the 2018 updated international care recommendations; available in various formats and languages

References

1. Duan D, Goemans N, Takeda S, et al. Duchenne muscular dystrophy. Nat. Rev. Dis. Primers. 2021;7(1):13. https://doi.org/10.1038/s41572-021-00248-3
2. Jackson, A. The McKell Living with Duchenne & Becker in Australia: Supporting families waiting for a cure. 2020. 27p. https://cdn.shopify.com/s/files/1/0506/8367/4813/files/McKell_Institute_-_Equity_Economics_-_Report_into_Duchenne_and_Becker_-_SOSDF_-_Final_Version_PDF.pdf?v=1614568181
3. Darras BT, Urion DK, Ghosh PS. Dystrophinopathies. 2020. Updated 20 January 2022. In: Adam MP, Mirzaa GM, Pagon RA, et al. GeneReviews® [Internet]. Seattle (WA): University of Washington Seattle. 1993-2024. Accessed 4 June 2024. https://www.ncbi.nlm.nih.gov/books/NBK1119
4. Genetic and Rare Diseases (GARD) Information Center. Duchenne muscular dystrophy. Accessed 4 June 2024. https://rarediseases.info.nih.gov/diseases/6291/duchenne-muscular-dystrophy
5. Duchenne muscular dystrophy. Accessed 4 June 2024. https://www.orpha.net/en/disease/detail/98896
6. Online Mendelian Inheritance in Man (OMIM). #310200 Muscular dystrophy, Duchenne Type; DMD. Accessed 4 June 2024. https://www.omim.org/entry/310200
7. healthdirect. Duchenne muscular dystrophy. Accessed 5 June 2024. https://www.healthdirect.gov.au/duchenne-muscular-dystrophy