Valvular Heart Disease USMLE Step 1 Practice Question
A 68 year old woman underwent mechanical aortic valve replacement 3 months ago. She now presents with fever and malaise. Blood cultures repeatedly grow coagulase negative catalase positive gram positive cocci that are novobiocin sensitive. Which of the following virulence traits most likely contributed to this organism's ability to infect her valve?
Answer choices
- ADextran mediated binding to fibrin on natural valves
- BBiofilm formation on prosthetic materialCorrect answer
- CM protein mediated complement inhibition
- DExotoxin A mediated ADP ribosylation
- ECapsule production that inhibits phagocytosis
- FLipoteichoic acid mediated platelet aggregation
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