Movement Disorders USMLE Step 1 Practice Question
A 2-year-old boy presents with progressive dysarthria, dystonia, toe-walking, and trunk arching. Vital signs: BP 95/60, HR 98, RR 22, Temp 37°C, SpO2 98%. He denies recent fever or headache. Slit lamp examination reveals Kayser-Fleischer rings. Laboratory studies show serum ceruloplasmin 8 mg/dL (normal 20-40), elevated 24-hour urinary copper excretion at 180 mcg/day, and normal liver function tests. Which of the following is the most likely diagnosis?
Answer choices
- AMitochondrial cytopathy
- BCerebral palsy
- CNiemann-Pick disease
- DGaucher disease
- EWilson diseaseCorrect answer
- FPantothenate kinase-associated neurodegeneration
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