Demyelinating Diseases USMLE Step 1 Practice Question
A 40-year-old woman presents with acute onset vertical diplopia, ataxia, and dysarthria. Vital signs: BP 128/82, HR 88, RR 16, Temp 37.2°C, SpO2 98%. Examination reveals vertical nystagmus and limb ataxia; cranial nerve examination is normal. MRI brain demonstrates T2-hyperintense lesions in brainstem and cerebellum. CSF analysis shows oligoclonal bands, mild pleocytosis (WBC 45/μL), and normal glucose. Which of the following is the most likely diagnosis?
Answer choices
- ACerebellar atrophy from alcohol
- BAcute cerebellar inflammation from varicella
- CNeuromyelitis optica spectrum disorderCorrect answer
- DWernicke encephalopathy
- EMultiple sclerosis
- FAutoimmune encephalitis associated with anti-NMDA receptor antibodies
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