Duchenne Muscular Dystrophy (DMD)
DMD is an X-linked recessive neuromuscular disorder caused by out-of-frame mutations in the dystrophin gene, leading to absence of functional dystrophin protein. Boys typically present in early childhood with progressive muscle weakness, loss of ambulation in adolescence, and cardiopulmonary complications in adulthood.
Symptoms & Presentation
- Delayed motor milestones, frequent falls, Gowers' sign (using hands to rise)
- Calf pseudohypertrophy, waddling gait
- Progressive proximal weakness, contractures
- Cardiomyopathy, arrhythmias
- Restrictive lung disease, sleep-disordered breathing
- Cognitive/behavioral difficulties in some patients
Diagnosis
- Elevated creatine kinase (CK) often >10,000 IU/L
- Genetic testing identifying dystrophin gene mutation (MLPA, NGS)
- Muscle biopsy with absent dystrophin (rarely needed now)
- Carrier testing for mothers; prenatal/preimplantation genetic diagnosis for family planning
Standards of Care
Corticosteroids
- Prednisone or deflazacort to slow muscle degeneration, prolong ambulation
- Monitor for weight gain, bone health, cataracts, behavior changes
Disease-Modifying Therapies
- Exon-skipping antisense oligonucleotides (eteplirsen, golodirsen, viltolarsen, casimersen) for specific mutations
- Stop-codon readthrough therapy (ataluren) in some regions
- Gene therapy (elevidys/delandistrogene moxeparvovec) delivering micro-dystrophin via AAV vectors for eligible patients
Cardiac & Pulmonary Care
- ACE inhibitors/beta-blockers starting in early teens to delay cardiomyopathy
- Annual echocardiogram or cardiac MRI
- Pulmonary function tests; assisted cough devices, nocturnal noninvasive ventilation when FVC declines
Rehabilitation & Assistive Technology
- Regular physical therapy, stretching, orthoses to prevent contractures
- Standing devices, power wheelchairs, home modifications
- Surgical management: tendon release, scoliosis correction when indicated
Multidisciplinary Support
- Neuromuscular clinic with cardiology, pulmonology, endocrinology, rehab, nutrition, mental health
- Transition planning to adult care
Living with DMD
- Track mobility, respiratory metrics, cardiac imaging, medications, gene therapy eligibility, and mental health
- Ensure immunizations (including pneumococcal, influenza) before gene therapy
- Support education/work adaptations, accessible transportation, caregiver respite
- Encourage social engagement and technology-assisted independence
Complications
- Loss of ambulation (typically early teens)
- Cardiomyopathy, arrhythmias leading to heart failure
- Respiratory failure requiring invasive ventilation
- Osteoporosis, fractures, endocrine issues from steroids
- Emotional/psychological strain on patient and family
Research & Future Directions
Gene editing (CRISPR), cell therapy (myoblast or stem-cell transplantation), utrophin upregulation, and combination exon-skipping are active areas of investigation.
Experimental & Emerging Treatments
- CRISPR Base Editing: Corrects mutations in situ, restoring dystrophin expression in preclinical models.
- Next-Gen Gene Therapies: Improved AAV capsids, dual-vector strategies to deliver full-length dystrophin.
- Utrophin Modulators: Small molecules boosting dystrophin homologue to stabilize muscle fibers.
- Digital Biomarkers: Wearables assessing ambulation and upper-limb function to tailor therapy.
Track DMD with Diagnoza.care
Plan Each Stage with Clarity – Log muscle strength assessments, mobility milestones, steroids/exon-skipping/gene therapy dosing, cardiac/pulmonary tests, surgeries, assistive devices, school/therapy appointments, and mental health notes; capture side effects; and let the AI companion remind you of surveillance timelines and clinical trial opportunities.
Medical Disclaimer: Informational only. Work with a certified neuromuscular center for genetic counseling, therapy selection, cardiopulmonary monitoring, and transition planning.
Sources: Muscular Dystrophy Association, Parent Project Muscular Dystrophy, Centers for Disease Control and Prevention