Movement Disorders USMLE Step 1 Practice Question
A 55-year-old woman with no psychiatric history presents to the emergency department with involuntary choreiform movements of the face, tongue, and extremities that began 3 months after initiating risperidone for newly diagnosed schizophrenia. She reports the movements are worse with stress and improve slightly with voluntary movement. The patient discontinued risperidone 4 weeks ago at her own discretion due to concern about side effects, but the movements have persisted and may have worsened. Vital signs are stable with temperature 37.1°C. Neurologic examination reveals orofacial dyskinesias, lingual protrusion, and irregular limb movements. Brain MRI is unremarkable. Recent laboratory work including CBC, CMP, and RPR are normal. Which of the following is the most likely diagnosis?
Answer choices
- AAcute dystonia
- BDrug-induced parkinsonism
- CNeuroleptic malignant syndrome
- DAkathisia
- ETardive dyskinesiaCorrect answer
- FSydenham's chorea
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