Mycology/Parasitology USMLE Step 1 Practice Question
A 58-year-old woman with no prior medical history undergoes prosthetic aortic valve replacement. Postoperatively, she develops fever (38.9°C), tachycardia (104 bpm), and tachypnea (22 breaths/min). Blood cultures remain negative despite 48 hours of vancomycin and gentamicin. Transthoracic echocardiography shows a new 8-mm vegetation on the prosthetic valve. She denies IV drug use and has no indwelling catheters. Which pathogen is most likely responsible for this prosthetic valve endocarditis?
Answer choices
- ACandida albicansCorrect answer
- BNocardia asteroides
- CTrichophyton rubrum
- DHistoplasma capsulatum
- EActinomyces israelii
- FAspergillus fumigatus
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