Demyelinating Diseases USMLE Step 1 Practice Question
A 31-year-old man with no past medical history presents with progressive painful paresthesias in both feet and hands over 4 weeks following a diarrheal illness 2 weeks ago. Vital signs: BP 128/82, HR 92, RR 18, temp 37°C, SpO2 98%. Neurologic exam reveals symmetric lower extremity weakness; cranial nerves are intact. Nerve conduction studies demonstrate demyelination with conduction slowing. CSF protein is mildly elevated at 58 mg/dL. Which diagnosis best explains these findings?
Answer choices
- AGuillain-Barré syndromeCorrect answer
- BMultiple sclerosis
- CChronic inflammatory demyelinating polyneuropathy
- DLyme disease
- EVincristine toxicity
- FAcute intermittent porphyria
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