Bacterial Infections USMLE Step 1 Practice Question
A 67 year old man in the intensive care unit develops fever and worsening oxygenation 8 days after intubation. Sputum culture grows a motile gram negative rod that forms red pigmented colonies and has caused outbreaks associated with contaminated respiratory equipment. Which of the following is the most likely causal organism?
Answer choices
- APseudomonas aeruginosa
- BSerratia marcescensCorrect answer
- CKlebsiella pneumoniae
- DEnterococcus faecalis
- EEscherichia coli
- FStreptococcus pneumoniae
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