During morning rounds in the intensive care unit, the medical team discusses the care of a patient who was recently treated for a severe asthma exacerbation. The patient had a central venous catheter placed days ago, which was removed yesterday when he developed rigors and a temperature of . Empiric intravenous vancomycin and piperacillin-tazobactam were started at that time. Today, the microbiology laboratory reports that two sets of blood cultures are positive for methicillin-susceptible *Staphylococcus aureus* (MSSA). The isolate is susceptible to oxacillin, cefazolin, and vancomycin. The patient's vital signs are now stable and he is afebrile. Which of the following is the most appropriate next step in pharmacotherapy?
- AMaintain the current regimen of vancomycin and piperacillin-tazobactam
- BDe-escalate to intravenous vancomycin monotherapy
- Transition therapy to intravenous cefazolin monotherapyAnswer
- DSwitch to oral trimethoprim-sulfamethoxazole monotherapy
- ERetain vancomycin and replace piperacillin-tazobactam with intravenous gentamicin
Answer
The most appropriate action is to transition therapy to intravenous cefazolin monotherapy.
Transitioning to intravenous cefazolin monotherapy is correct because MSSA bacteremia should be treated with a targeted anti-staphylococcal beta-lactam. Drugs like cefazolin, nafcillin, or oxacillin are considered superior to vancomycin for MSSA infections due to faster bacterial clearance and improved survival rates. Discontinuing the broad-spectrum empiric regimen in favor of this targeted therapy is the standard of care.
Step-by-Step Solution
Key Concept
The optimal treatment for methicillin-susceptible *Staphylococcus aureus* (MSSA) bacteremia is an intravenous anti-staphylococcal beta-lactam, such as cefazolin, rather than vancomycin, as it provides superior clinical outcomes and aligns with antimicrobial stewardship principles.
Estimated Time:1m 30s