Bacterial Infections USMLE Step 1 Practice Question
A 68 year old woman presents with 1 week of low grade fever and malaise. Two months ago she underwent prosthetic aortic valve replacement. Temperature is 38.1 C (100.6 F). Cardiac examination reveals a new murmur. Blood cultures grow catalase positive, coagulase negative gram positive cocci that are novobiocin sensitive. Which of the following properties most contributes to this organism’s pathogenesis in this patient?
Answer choices
- ASpore formation in anaerobic tissue
- BBiofilm formation on foreign materialCorrect answer
- CExotoxin A production
- DMotility via polar flagella
- EAlpha toxin induced hemolysis
- FProduction of protein A that binds to the Fc portion of immunoglobulins
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