Demyelinating Diseases USMLE Step 1 Practice Question
A 45-year-old man with known multiple sclerosis presents with acute onset of bilateral leg weakness, urinary retention, and loss of perianal sensation. Vital signs show BP 128/82, HR 88, RR 16, temperature 37.2°C, and SpO2 98% on room air. MRI of the thoracic spine reveals a longitudinal T2-hyperintense lesion extending 3 vertebral segments with central cord involvement. Serum vitamin B12 level is normal. He denies recent fever or bowel dysfunction. Which of the following is the most appropriate next step in management?
Answer choices
- ALumbar puncture for CSF analysis
- BInterferon-beta therapy
- CPlasmapheresis alone
- DObservation with supportive care
- EHigh-dose intravenous methylprednisoloneCorrect answer
- FEmergency surgical decompression for suspected extrinsic cord compression
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