Friedreich ataxia is an autosomal recessive disorder and is the most common inherited ataxia. The dorsal root ganglia, dorsal columns, corticospinal tracts and heart are predominantly affected.
Epidemiology
- Incidence: 1/30 000-1/50 000
- Gender: Male = Female
Clinical Presentation
- A slowly progressive ataxia
- Mean age of onset 10-15 years
- May present in adulthood with milder disease
Physical Signs
- Dysarthria
- Spasticity in lower limbs
- Muscle weakness
- Absent/ reduced lower limb reflexes with extensor plantars
- Reduction/ loss of vibration sense and proprioception (dorsal columns)
- Progressive gait and limb ataxia
- Pes cavus
- Scoliosis
- Optic nerve atrophy
- Evidence of cardiomyopathy
Complications
- Average age of death is <40 years, most commonly due to cardiomyopathy.
- Diabetes mellitus (30%)