A 68-year-old woman is evaluated in the hospital on day 3 of admission for acute cholangitis. She initially presented with fever, right upper quadrant pain, and jaundice. She was started on empiric intravenous piperacillin-tazobactam and successfully underwent endoscopic retrograde cholangiopancreatography with biliary stone extraction.
Currently, she is afebrile and her abdominal pain has entirely resolved. Blood and bile cultures obtained on admission both grow *Klebsiella pneumoniae*. The antimicrobial susceptibility report is as follows:
| Antimicrobial | Susceptibility |
|---|---|
| Ampicillin | Resistant |
| Ceftriaxone | Susceptible |
| Ciprofloxacin | Susceptible |
| Meropenem | Susceptible |
| Piperacillin-tazobactam | Susceptible |
Which of the following is the most appropriate next step in the patient's pharmacotherapy?
- AContinue intravenous piperacillin-tazobactam
- BAdd intravenous vancomycin
- Transition to intravenous ceftriaxoneAnswer
- DTransition to intravenous ampicillin
- ETransition to intravenous meropenem
Answer
Transition to intravenous ceftriaxone.
Ceftriaxone is the most appropriate choice because it provides targeted, narrow-spectrum coverage against the susceptible *Klebsiella pneumoniae* isolate. Antimicrobial stewardship guidelines strongly recommend de-escalating from broad-spectrum empiric therapy (like piperacillin-tazobactam) to a narrower-spectrum agent once culture and susceptibility data become available and the patient is clinically stable.
Step-by-Step Solution
Key Concept
Antimicrobial stewardship and de-escalation of empiric antibiotics based on culture results.
Estimated Time:1m 0s