Influence of T2 Candida Testing for Rapid Diagnosis of Candida Infections on Antifungal Stewardship Efforts at a Large Academic Medical Center: A Retrospective, Single-center Study

Abstract

BackgroundAntimicrobial stewardship has traditionally focused on the optimal use of antibacterial agents. Much less attention is focused on the optimal use of antifungal therapy (AFT). The high mortality and emergence of resistance in invasive infections due to Candida presents a critical opportunity for AFT stewardship. The T2Candida (T2C) panel is a rapid diagnostic test using magnetic resonance to detect 5 different species of Candida in whole blood. T2C has a sensitivity of 91%, specificity of 99%, negative predictive value of 99%, and generates results in <6 hours.MethodsWe conducted a retrospective analysis of candidemia cases at the UAB Medical Center in 2015–16. T2C testing was introduced in January 2016. We compared outcomes among patients prior to and following the implementation of routine T2C testing. The focus of the study was to gather data on AFT, time to initiation of therapy(TTT), and overall use of echinocandin patterns during the study period utilizing days of therapy (DOT) /1000 pt days as a parameter.ResultsIn 2015 and 2016, 100 patients and 138 patients with candidemia, respectively, were included in the analysis. In 2016, there were 354 T2C valid results; 36 (10.2%) were positive and 318 (89.8%) were negative. The TTT for all candidemic patients in 2015 was 2.02 days vs 1.15 days for candidemic patients in 2016, including all who were blood culture(BC)+ and/or T2C+ (P < 0.0001). For patients with candidemia in 2016, TTT in the T2C+ group vs those in whom only BC+ was 0.09 days and 1.69 days, respectively (P < 0.00001). Comparing results for 2015 and 2016, we observed echinocandin (ECH) usage of 15.1 and 17.8 DOT/1000 pt days, respectively.ConclusionWe observed a significant decrease in the TTT for candidemic patients since introduction of the T2C. These results suggest that rapid identification of candidemia may be an important tool for AFT stewardship. We hypothesize that other factors, such as the updated IDSA Treatment Guidelines for Candidiasis and increased attention to the early intervention for sepsis campaign, may have influenced the use of ECH, and is supported by the observation that along with the decrease in TTT, we observed a slight increase in the DOT/ 1000 pt days between 2015 and 2016, suggesting more liberal use of empiric ECH.Disclosures All authors: No reported disclosures.