1858. Sequential Time to Positivity as a Prognostic Indicator in <i>Staphylococcus aureus</i> bacteremia

Abstract Background The role of sequential blood culture time to positivity (TTP) as a surrogate marker for bacterial load and prognostic indicator in S. aureus bacteremia (SAB) is not well established the literature. Methods We performed single healthcare system, multi-site, retrospective review adult patients with positive between January 2019 December 2019. Sequential TTP was defined first subsequent cultures obtained from SAB at least 24 hours. adapted previously described ratio &amp;lt; 1.5 cut-off study groups. Infective endocarditis (IE) according modified Duke’s criteria. High-grade growth organism two or more sets &amp;gt;50% all bottles collected. Descriptive, comparative statistics survival analysis were using Python 3 IBM SPSS Statistics Windows, Version 27.0. Armonk, NY: Corp. Results A total 602 identified, 186 who met criteria included. Sixty-nine (37%) female, mean age 63.6 years. Patients initial 12 hours had higher 30-day 90-day mortality than those ≥ &amp;gt; rates cardiac prosthetic device (30 [26.1%] vs. 9 [12.7%], p = .03) high-grade (106 [92.2%] 56 [78.9%], .01). In univariate analysis, history myocardial infarction, device, findings native valve vegetation echocardiogram significant predictors 1.5. multivariate (OR 2.4; 95% CI 1.2-4.84), (OR, 0.3; CI, 0.13- 0.77) independent (Table 1 2). No differences 30- day based on seen (Figure 1). Figure 1.Kaplan-Meier (KM) curves log rank test results X-axis represents days elapsed collection. Number risk events are given below x-axis each group. significantly lower compared There no statistically ratio. Conclusion SAB, second TPP associated presence bacteremia. Initial survival; however didn’t predict mortality. Disclosures All Authors: reported disclosures.