Duchenne Muscular Dystrophy
Most common muscular dystrophy of childhood.
Epidemiology and Risk Factors
DMD:
- X-linked recessive disorder
- Incidence of 1:3,500 live births
Pathophysiology
Genetic absence of the gene coding for the dystrophin protein, which:
- Prevents dystrophin expression in muscle sarcolemma
Subsequent weakness. - Muscle fibres are poorly tethered due to sarcolemma weakness
- Muscle fibres are gradually replaced with fibrous connective tissue
Aetiology
Clinical Manifestations
Generally:
- Presents in early childhood
- Progressive proximal muscle wasting
- Waddling gait
- Pseudohypertrophy of calf muscles
Diagnostic Approach and DDx
Investigations
Management
Anaesthetic Considerations
Marginal and Ineffective Therapies
Complications
Include:
- Contractures
- Scoliosis
- Restrictive lung disease
- Cardiomyopathies
DCM in 50% of children by age 12.
Prognosis
Usually fatal in late adolescence due to:
- Respiratory failure
- Cardiac failure