Pneumonia USMLE Step 1 Practice Question
A 45-year-old man is admitted to the ICU following complicated abdominal surgery with anastomotic repair. On hospital day 5, he develops fever (38.9°C), tachycardia (heart rate 110/min), and tachypnea (respiratory rate 22/min) while on mechanical ventilation. Endotracheal suctioning yields copious purulent secretions. Chest X-ray shows a new infiltrate in the right lower lobe. Gram stain of endotracheal aspirate demonstrates gram-negative rods. Laboratory studies show WBC 14,500/μL and normal renal function. The patient has received only perioperative cefazolin prophylaxis. Which of the following is the most appropriate initial empiric antibiotic regimen?
Answer choices
- ACeftriaxone and gentamicin
- BAmpicillin-sulbactam monotherapy
- CPiperacillin-tazobactam plus a respiratory fluoroquinoloneCorrect answer
- DClindamycin and tobramycin
- EAzithromycin monotherapy
- FTrimethoprim-sulfamethoxazole monotherapy
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