Duchenne muscular dystrophy (DMD) is a genetic disorder characterized by progressive muscle weakness and degeneration. It primarily affects males, with symptoms typically appearing in early childhood (between 2 to 3 years). It is a progressive neuromuscular disorder characterized by the degeneration and weakening of skeletal muscles.
Due to the absence or deficiency of dystrophin, a protein essential for maintaining muscle strength, the muscle fibres gradually deteriorate over time. As the disease progresses, individuals with DMD experience increasing difficulties in mobility and various health complications.
Causes:
Duchenne muscular dystrophy (DMD) is caused by a mutation in the dystrophin gene, responsible for producing a protein crucial for muscle integrity. This condition primarily affects boys, with symptoms emerging during early childhood.
Symptoms:
The symptoms of Duchenne muscular dystrophy typically manifest in early childhood, usually between the ages of 3 and 5. Common signs include:
Muscle weakness: Children may have trouble walking or exhibit a waddling gait.
Delayed motor milestones: They may experience delays in reaching developmental milestones like sitting or standing.
Frequent falls: Due to weakened muscles, affected individuals are prone to tripping and falling.
Gower's sign: Children may use their hands and arms to push themselves up from a squatting or lying position.
Enlarged calves: Some individuals develop calf muscles that appear larger than usual due to muscle fibre replacement by fat and connective tissue.
Diagnosis:
Diagnosing Duchenne muscular dystrophy involves a combination of clinical evaluations, family history assessments, and diagnostic tests. Diagnosis includes physical examination and evaluation of symptoms are crucial initial steps. Genetic testing can confirm the presence of dystrophin gene mutations. Muscle biopsies, electromyography (EMG), and blood tests may be conducted to support the diagnosis further and assess muscle function.
Treatment:
Treatments are aimed at managing symptoms, slowing disease progression and increasing quality of life. These include:
Steroid therapy: Corticosteroids, such as prednisone or deflazacort, are commonly prescribed to help delay muscle degeneration and maintain muscle strength.
Physical therapy: Regular physical therapy sessions can help maintain joint flexibility, improve mobility, and delay muscle contractures.
Assistive devices: Mobility aids, orthopaedic devices, and respiratory support may be recommended to address specific needs and enhance functional abilities.
Cardiac care: Regular monitoring and management of cardiac function are essential, as DMD can impact heart health. Angiotensin-converting enzyme blockers, angiotensin receptor blockers and beta blockers are used if there are variations in the electrocardiogram (ECG).
Exon-skipping drugs: FDA-approved medications such as eteplirsen and golodirsen can address specific genetic mutations in the dystrophin gene, producing a partially functional dystrophin protein.
Gene therapy: Elevidys is a gene therapy that delivers a shorter version of dystrophin, i.e., Elevidys micro-dystrophin.
Survival in patients with DMD: Initially, the survival rate in patients with DMD is low. However, with the increase in assistive devices and cardiac care, survival increased by up to 30 years.
Duchenne muscular dystrophy is a complex and challenging condition that affects individuals and their families. Early diagnosis, comprehensive medical care, and supportive interventions can help manage symptoms, improve quality of life, and potentially slow disease progression.