Demyelinating Diseases USMLE Step 1 Practice Question
A 26-year-old woman presents with diplopia, dysarthria, and dysdiadochokinesia one week after a viral illness. Vital signs: BP 118/76, HR 88, RR 16, Temp 37.2°C, SpO2 98%. Brain MRI demonstrates multiple T2 hyperintense lesions in the brainstem, corpus callosum, and periventricular white matter with contrast enhancement. CSF analysis reveals oligoclonal bands and elevated IgG index. No fever currently. Which diagnosis best explains these findings?
Answer choices
- AAcute disseminated encephalomyelitisCorrect answer
- BTumefactive demyelination
- CMultiple sclerosis
- DViral encephalitis
- EPosterior reversible encephalopathy syndrome
- FBickerstaff brainstem encephalitis with anti-GQ1b antibodies
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