Neuromuscular Disorders USMLE Step 1 Practice Question
A 55-year-old woman with severe asthma on high-dose prednisone (60 mg daily) for 6 months presents with progressive difficulty rising from chairs and climbing stairs. Vital signs: BP 138/82, HR 92, RR 16, Temp 98.6°F, SpO2 98%. Examination reveals symmetric proximal lower extremity weakness without pain or tenderness. Serum creatine kinase is 95 U/L. EMG shows no myopathic changes. Which diagnosis best explains her presentation?
Answer choices
- AGuillain-Barré syndrome
- BGlucocorticoid induced myopathyCorrect answer
- CLambert-Eaton syndrome
- DPolymyositis
- EDermatomyositis
- FMyasthenia gravis
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