Demyelinating Diseases USMLE Step 1 Practice Question
A 28-year-old man presents with acute paraplegia developing over 24 hours. Vital signs: BP 128/82, HR 92, RR 16, Temp 37.2°C, SpO2 98% on room air. Examination reveals sensory level at T5 and urinary retention. He denies prior optic neuritis or brain symptoms. MRI of spine demonstrates longitudinally extensive transverse myelitis spanning 4 vertebral levels with central cord involvement. Serum AQP4 antibodies are positive. Which diagnosis best explains these findings?
Answer choices
- ASpinal cord infarction
- BCervical spondylotic myelopathy
- CTransverse myelitis due to viral infection
- DNeuromyelitis optica spectrum disorderCorrect answer
- EMultiple sclerosis
- FParaneoplastic myelitis associated with small cell lung cancer
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