Friedreich’s Ataxia

Question 1

Friedreich’s Ataxia presentation

Answer 1

Examine this young man’s neurological system.

Question 2

Clinical signs of Friedreich’s ataxia

Answer 2

1. Young adult, wheelchair (or ataxic gait)
2. Pes cavus
3. Bilateral cerebellar ataxia (ataxic hand shake + other arm signs, dysarthria, nystagmus)
4. Leg wasting and weakness with absent reflexes and bilateral upgoing plantars
5. Posterior column signs (loss of vibration and joint position sense)

Question 3

Other signs of Friedreich’s ataxia

Answer 3

1. Kyphoscoliosis: the usual childhood presentation
2. Optic atrophy (30%)
3. High‐arched palate
4. Sensorineural deafness (10%)
5. Listen for murmur of HOCM (most common cause of death)
6. Ask to dip urine (10% develop diabetes)

Question 4

Discussion of Friedreich’s ataxia

Answer 4

1. Autosomal recessive trinucleotide repeat disorder (GAA) on chromosome 9 in gene that encodes frataxin (iron binding protein). Leads to impairment in mitochondrial functioning
2. Onset is during teenage years
3. Survival rarely exceeds 20 years from diagnosis
4. There is an association with HOCM and a mild dementia.

Question 5

ِCauses of extensor plantars with absent knee jerks

Answer 5

1. Friedreich’s ataxia
2. Subacute combined degeneration of the cord (vitamin B12 Cobalamin deficiency)
3. Motor neurone disease
4. Taboparesis (Syphilis)
5. Conus medullaris lesions
6. Combined upper and lower pathology, e.g. cervical spondylosis with peripheral neuropathy