Demyelinating Diseases USMLE Step 1 Practice Question
A 28-year-old man presents with acute bilateral leg paralysis, urinary retention, and acute lower back pain following lower back sensory loss. Vital signs: BP 128/82 mmHg, HR 92/min, RR 16/min, temp 37.2°C, SpO2 98% on room air. MRI cervical and thoracic spine shows T2 hyperintensity spanning 3 thoracic vertebral segments; brain MRI is normal. CSF analysis reveals elevated protein. Which antibody is most likely positive?
Answer choices
- AAnti-nuclear antibody (ANA)
- BAnti-NMDA receptor
- CAnti-aquaporin-4 (AQP4)Correct answer
- DAnti-myelin oligodendrocyte glycoprotein (MOG)
- EAnti-amphiphysin
- FAnti-aquaporin-1 (AQP1)
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