Neuromuscular Disorders USMLE Step 1 Practice Question
A 67-year-old man initiated high-intensity atorvastatin therapy 3 weeks ago following myocardial infarction. He now presents with diffuse myalgias and proximal lower extremity weakness. Vital signs show BP 138/82, HR 88, RR 16, temp 37°C, SpO2 98% on room air. Serum creatine kinase is elevated at 1,200 U/L. Urine myoglobin is negative. Which of the following is the most likely explanation for his presentation?
Answer choices
- AALS
- BMyasthenia gravis
- CPeriodic paralysis
- DAcute inflammatory demyelinating polyneuropathy
- EDrug induced toxic myopathyCorrect answer
- FNecrotizing autoimmune myopathy (anti-HMGCR antibody-associated)
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