Demyelinating Diseases USMLE Step 1 Practice Question
A 53-year-old man with a 20-year history of alcohol use disorder presents with chronic symptomatic hyponatremia (Na+ 114 mEq/L). During hospitalization, his sodium is rapidly corrected to 132 mEq/L over 12 hours. Two days later, he develops dysarthria, dysphagia, and quadriparesis. Vital signs show BP 138/82, HR 88, RR 16, temperature 37.2°C. MRI reveals pontine hyperintensities on T2-weighted imaging. Cranial nerves IIâXII remain intact. Which demyelinating condition best explains these findings?
Answer choices
- ACentral pontine myelinolysisCorrect answer
- BTransverse myelitis
- CMultiple sclerosis
- DGuillain Barré syndrome
- EAcute disseminated encephalomyelitis
- FOsmotic demyelination syndrome affecting the extrapontine regions
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