Movement Disorders USMLE Step 1 Practice Question
A 7-year-old boy presents to the emergency department with a 3-week history of involuntary jerking movements of his arms and legs, emotional outbursts, and difficulty with fine motor tasks such as writing. His mother reports he had a sore throat 2 months ago that resolved without treatment. On examination, he has unilateral facial grimacing, hypotonia, and a new early diastolic murmur heard best at the left lower sternal border. His mother also notes he has been dropping objects and appears clumsy. Laboratory studies reveal an elevated erythrocyte sedimentation rate of 58 mm/hr and C-reactive protein of 12 mg/dL. Throat culture obtained today is negative. Which of the following is the most likely diagnosis?
Answer choices
- AAcute disseminated encephalomyelitis (ADEM)
- BPediatric autoimmune neuropsychiatric disorder associated with streptococcal infection (PANDAS)
- CAcute cerebellar ataxia
- DSydenham chorea as a manifestation of acute rheumatic feverCorrect answer
- EWilson disease
- FTourette syndrome
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