Neuromuscular Disorders USMLE Step 1 Practice Question
A 19-year-old man presents with recurrent episodes of flaccid proximal weakness beginning after strenuous exercise or large carbohydrate meals. Between episodes he is neurologically normal. Current vital signs show BP 138/82, HR 88, RR 16, temperature 37°C, SpO2 98% on room air. Serum potassium is 2.8 mEq/L during the current attack. Creatine kinase is normal. Electromyography shows no denervation. Which of the following is the most likely diagnosis?
Answer choices
- ATetanus
- BGuillain-Barré syndrome
- CHypokalemic periodic paralysisCorrect answer
- DSpinal muscular atrophy
- EMyasthenia gravis
- FThyrotoxic periodic paralysis
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