Abstract
Background
The recommended duration of antimicrobial treatment for Staphylococcus aureus bacteremia (SAB) is a minimum of 14 days. We compared the clinical outcomes of patients receiving short-course (SC; 6–10 days), or prolonged-course (PC; 11–16 days) antibiotic therapy for low-risk methicillin-susceptible SAB (MS-SAB).
Methods
Adults with MS-SAB in 1995–2018 were included from 3 independent retrospective cohorts. Logistic regression models fitted with inverse probability of treatment weighting were used to assess the association between the primary outcome of 90-day mortality and treatment duration for the individual cohorts as well as a pooled cohort analysis.
Results
A total of 645, 219, and 141 patients with low-risk MS-SAB were included from cohorts I, II, and III. Median treatment duration in the 3 SC groups was 8 days (interquartile range [IQR], 7–10), 9 days (IQR, 8–10), and 8 days (IQR, 7–10). In the PC groups, patients received a median therapy of 14 days (IQR, 13–15), 14 days (IQR, 13–15), and 13 days (IQR, 12–15). No significant differences in 90-day mortality were observed between the SC and PC group in cohort I (odds ratio [OR], 0.85 [95% confidence interval {CI}, .49–1.41]), cohort II (OR, 1.24 [95% CI, .60–2.62]), or cohort III (OR, 1.15 [95% CI, .24–4.01]). This result was consistent in the pooled cohort analysis (OR, 1.05 [95% CI, .71–1.51]). Furthermore, duration of therapy was not associated with the risk of relapse.
Conclusions
In patients with low-risk MS-SAB, shorter courses of antimicrobial therapy yielded similar clinical outcomes as longer courses of therapy.
Impact of an Antimicroibal Stewardship Bundle of Rapid Identification of Methicillin Susceptibility and Active Intervention on Treatment of Staphylococcus aureus Bacteremia