Inflammation and Immune Pathology USMLE Step 1 Practice Question
A 34-year-old woman presents with sudden-onset polyarthralgias, fever, and a painful erythematous rash on her lower extremities. Vital signs show temperature 38.5°C, heart rate 102/min, blood pressure 128/82 mmHg, and SpO2 98% on room air. Skin biopsy demonstrates leukocytoclasia with fibrinoid necrosis of small blood vessels. Laboratory studies reveal elevated ESR and normal complement levels. She denies recent upper respiratory infection. Which of the following is the most likely diagnosis?
Answer choices
- AIgA vasculitisCorrect answer
- BSystemic lupus erythematosus
- CGranulomatosis with polyangiitis
- DHypersensitivity vasculitis
- EPolyarteritis nodosa
- FCryoglobulinemia
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