Pinpointing a diagnosis for a patient with parkinsonism

Slowing gait and failing vision point to a more sinister condition.

Sam is a 90-year-old man who complains of a six-month history of slowing gait. He also has a history of hypertension, renal impairment and recent-onset memory loss.


He is not taking any medication that could cause parkinsonism, including antipsychotic or antiemetic drugs. There is no known history of stroke.

Despite the symptoms, at the time of the first presentation, he has not had any falls or impairment of activities of daily living.

On initial examination, he has slowness or brady-kinesia in all limbs and mild