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Published on: May 5, 2016
Cefazolin for Methicillin-Susceptible Staphylococcus aureus Bacteremia
, Todd C Lee1, Lauren A Barina2
1Department of Medicine, Division of Infectious Diseases, McGill University, Montreal.
The New England Journal of Medicine
|June 17, 2026
Summary
Cefazolin is as effective as antistaphylococcal penicillins for treating methicillin-susceptible Staphylococcus aureus bacteremia. This study found cefazolin also significantly reduced acute kidney injury incidence in patients.
Area of Science:
- Infectious Diseases
- Clinical Pharmacology
- Antimicrobial Stewardship
Background:
- Staphylococcus aureus bacteremia presents a significant mortality risk.
- Optimal antibiotic choice for methicillin-susceptible S. aureus bacteremia remains debated.
Purpose of the Study:
- To compare the efficacy and safety of cefazolin versus antistaphylococcal penicillins for treating S. aureus bacteremia.
- To determine if cefazolin is noninferior to flucloxacillin or cloxacillin regarding 90-day mortality.
Main Methods:
- An international Bayesian adaptive platform trial randomized adult patients with S. aureus bacteremia.
- The primary outcome was 90-day all-cause mortality, analyzed using a Bayesian logistic-regression model.
- Secondary outcomes included acute kidney injury within 14 days.
Main Results:
- Cefazolin demonstrated noninferiority to antistaphylococcal penicillins for 90-day mortality (15.0% vs. 17.0%).
- Cefazolin was associated with a significantly lower incidence of acute kidney injury (13.9% vs. 19.6%).
- The probability of cefazolin noninferiority was 99.2%, and superiority for reduced AKI was 99.7%.
Conclusions:
- Cefazolin is a suitable alternative to antistaphylococcal penicillins for methicillin-susceptible S. aureus bacteremia.
- Cefazolin use is linked to a reduced risk of acute kidney injury compared to flucloxacillin or cloxacillin.
- These findings support cefazolin in antimicrobial guidelines for S. aureus bacteremia.
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