Movement Disorders USMLE Step 1 Practice Question
A 58-year-old man with a 6-year history of Parkinson disease presents with severe involuntary writhing movements of his arms and legs that develop 45 minutes after taking levodopa and intensify with dose increases. Vital signs: BP 138/82, HR 92, RR 16, Temp 37°C, SpO2 98%. He denies tremor at rest currently. MRI brain shows no acute abnormalities. He takes levodopa-carbidopa and amantadine. Which of the following is the most likely diagnosis?
Answer choices
- AAthetosis from basal ganglia stroke
- BTardive dyskinesia
- CLevodopa-induced dyskinesiaCorrect answer
- DHuntington disease
- EEssential tremor
- FAmantadine-induced myoclonus
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