Movement Disorders USMLE Step 1 Practice Question
A 27-year-old man presents with abrupt-onset, involuntary jerky movements of his face and distal extremities. His father died after years of progressive abnormal movements and cognitive decline. Vital signs: BP 118/76, HR 88, RR 16, temp 37°C, SpO2 98%. MRI demonstrates caudate nucleus atrophy. Serum copper and ceruloplasmin levels are normal. He denies recent antipsychotic use. Which of the following is the most likely diagnosis?
Answer choices
- AHuntington diseaseCorrect answer
- BRestless legs syndrome
- CParkinson disease
- DDystonia
- EEssential tremor
- FSydenham chorea
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