Demyelinating Diseases USMLE Step 1 Practice Question
A 19-year-old previously healthy male presents 2 weeks after an upper respiratory viral illness with acute confusion and generalized seizure. Vital signs: BP 118/76, HR 102, RR 20, Temp 37.8°C, SpO2 98%. He reports bilateral arm weakness but denies focal sensory deficits. CSF analysis reveals elevated protein (68 mg/dL) with mild lymphocytic pleocytosis (45 cells/μL). Brain MRI demonstrates multifocal white matter lesions. Which of the following is the most likely diagnosis?
Answer choices
- ASubcute sclerosing panencephalitis
- BBacterial meningitis
- CAcute disseminated encephalomyelitisCorrect answer
- DMultiple sclerosis
- EHerpes simplex encephalitis
- FAcute hemorrhagic leukoencephalitis
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