Bacterial Infections USMLE Step 1 Practice Question
A 61 year old man presents with fever and diffuse abdominal pain 5 days after emergency surgery for a perforated appendix. CT scan shows multiple intraabdominal abscesses. Aspiration of the abscess yields foul smelling material, and culture grows an anaerobic gram negative rod. Which of the following organisms is the most likely cause of this patient’s infection?
Answer choices
- AHaemophilus influenzae
- BEscherichia coli O157:H7
- CVibrio cholerae
- DPseudomonas aeruginosa
- EBacteroides fragilisCorrect answer
- FPrevotella melaninogenicus
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