Neuromuscular Disorders USMLE Step 1 Practice Question
A 41-year-old man presents 10 days after acute gastroenteritis with diplopia, gait unsteadiness, and mild proximal leg weakness. Vital signs: BP 138/82, HR 92, RR 18, temp 37.2°C, SpO2 98%. Neurologic exam reveals absent deep tendon reflexes bilaterally and mild ophthalmoplegia. CSF analysis shows elevated protein (78 mg/dL) with normal glucose and cell count. He denies recent vaccination. Which of the following is the most likely diagnosis?
Answer choices
- AMultiple sclerosis
- BMiller Fisher variant of Guillain Barré syndromeCorrect answer
- CMyasthenia gravis
- DBotulism
- ELambert Eaton myasthenic syndrome
- FAcute inflammatory demyelinating polyradiculoneuropathy (AIDP)
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