Neuromuscular Disorders USMLE Step 1 Practice Question
A 51-year-old woman presents with progressive proximal muscle weakness and difficulty rising from a chair over 3 months. Vital signs show BP 128/82, HR 92, RR 16, temp 37.2°C, SpO2 98%. Examination reveals violaceous discoloration around the eyelids, scaly erythematous papules over the knuckles, and proximal lower extremity weakness (4/5). Serum creatine kinase is elevated at 1,800 U/L. Dysphagia is absent. She takes no immunosuppressive medications. Which of the following is the most likely diagnosis?
Answer choices
- AMyasthenia gravis
- BPolymyositis
- CInclusion body myositis
- DALS
- EDermatomyositisCorrect answer
- FSystemic sclerosis with myositis
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