Reported penicillin allergy had no significant effect on 30- or 90-day mortality in patients with methicillin-susceptible Staphylococcus aureus (MSSA) bacteremia, a recent study found. The retrospective cohort study of adults with MSSA bacteremia from 2010-2015 included 318 patients with MSSA bacteremia. Outcomes were examined according to reported penicillin allergy. Researchers found:

• Reported penicillin allergy had no significant effect on adjusted 30-day mortality (OR, 0.73).
• Patients with reported penicillin allergy were more likely to receive vancomycin, but a large number received cefazolin regardless of reported allergy.
• Non-penicillin allergic patients receiving vancomycin for treatment of MSSA bacteremia had the highest mortality rates overall.
• Receipt of a beta-lactam was the strongest predictor of survival.