Demyelinating Diseases USMLE Step 1 Practice Question
A 38-year-old man presents with a 6-month history of progressive tremor, dysarthria, and cognitive decline. Vital signs: BP 128/82, HR 88, RR 16, Temp 37.2°C, SpO2 98% on room air. Brain MRI demonstrates cortical ribboning and basal ganglia hyperintensity on DWI sequences. CSF analysis reveals elevated 14-3-3 protein and positive RT-QuIC. EEG shows periodic sharp wave complexes. Serum protein electrophoresis is normal. Which of the following is the most likely diagnosis?
Answer choices
- AMultiple system atrophy
- BCreutzfeldt-Jakob diseaseCorrect answer
- CProgressive supranuclear palsy
- DParkinson disease with dementia
- EAlzheimer disease
- FFamilial Alzheimer disease with early-onset amyloid-β pathology
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