Bacterial Infections USMLE Step 1 Practice Question
A 62-year-old woman with metastatic breast cancer comes to the physician because of a 2-day history of fever, chills, and new gluteal lesions. The lesions began as painless red macules and evolved into painful ulcers overnight. She received her fourth course of palliative chemotherapy 2 weeks ago. Her temperature is 38.2°C (100.8°F). Laboratory studies show a leukocyte count of 2,000/mm³ (20% segmented neutrophils). A photograph of one of the skin lesions is shown. Which of the following virulence factors is most likely involved in the pathogenesis of this patient's skin finding?
Answer choices
- AEdema toxin
- BHeat-stable toxin
- CToxic shock syndrome toxin-1
- DExotoxin ACorrect answer
- EAlpha toxin
- FEndotoxin
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