Bacterial Infections USMLE Step 1 Practice Question
A 46 year old man with a history of mitral valve prolapse presents with 3 weeks of low grade fevers, fatigue, and weight loss. He underwent a dental extraction 1 month ago. Examination reveals a new regurgitant murmur and splinter hemorrhages. Blood cultures grow alpha hemolytic, optochin resistant gram positive cocci. Which of the following organisms is the most likely cause of this patient’s endocarditis?
Answer choices
- AStaphylococcus aureus
- BViridans streptococciCorrect answer
- CStreptococcus gallolyticus
- DStaphylococcus epidermidis
- EEnterococcus faecalis
- FStreptococcus pneumoniae
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