4th March 2024

A 23-year-old male presents with progressive gait instability

A 23-year-old male presents with progressive gait instability. This developed into a staggering gait with the inability to write. He developed a slurred speech that improved when his speech slowed down. On examination, he has a broad-based gait. 3/5 power was seen throughout all limbs, with loss of proprioception and vibration on examination. Romberg’s test was positive; he has dysdiadokokinesia, intention tremor and horizontal nystagmus. Reflexes were absent throughout his lower limbs. Blood tests showed raised HbA1c levels. His ECG showed diffuse T-wave inversion with ST-depression along all ECG leads with signs of left ventricular hypertrophy.

What is the likely underlying cause for his instability?

Select the SINGLE most appropriate option from the list below. Select ONE option only.