Friedreich's Ataxia

Exam Cram

• Friedreich's ataxia is the most common genetic ataxia,  autosomal recessive

• Pathophysiology: tri-nucleotide repeat disorder 

• Presentation: 5-25yrs; ataxia, loss of LL distal power &  sensation, reduced visual acuity or hearing

• Diagnosis: genetic testing

Outline

Background

• Incidence: 1/40,000, most commonly Caucasians

• Accounts for 50% of all ataxia, 75% under 25yrs

• Trinucleotide repeats affect frataxin (FXN) gene on chromosone 9

• Complications: heart failure & diabetes

• Cause of death: hypertrophic cardiomopathy

Assessment

History

• 5-25yrs caucasion

• Poor mobility

• Visual/ hearing issues

Examination

• Ataxia

• Reduced lower limb power, sensation & reflexes

Investigations

• Genetic testing: diagnostic- GAA repeats

• MRI of brain & spinal chord will show atrophy

• ECG: atrial fibrillation

Diagnosis

Diagnostic criteria: genetic testing (FXN gene)

Management

• Monitor mobility, heart, hearing and vision

• Physio, mobility, orthotics

• Medical mx of CHF, analgesia, infection prophylaxis

Med Reg Notes

Complications

Death most commonly occurs from cardiac arrhythmias

Prognosis

• Age of diagnosis usually < 20 years

• Loss of ability to walk 15yrs post diagnosis

• Life expectancy 40-50yrs

References and Resources

1. Williams CT, De Jesus O. Friedreich Ataxia. [Updated 2023 Aug 23]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2025 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK563199/ 

Written 2025.