Antimicrob Agents Chemother. 2021 Jul 6:AAC0044121. doi: 10.1128/AAC.00441-21. Online ahead of print.
Background: Decisions regarding which rapid diagnostic tests (RDT) for bloodstream infections to implement remains challenging given the diversity of organisms detected by different platforms. We used the Desirability of Outcome Ranking Management of Antimicrobial Therapy (DOOR-MAT) as a framework to compare two RDT platforms on potential desirability of antimicrobial therapy decisions. Methods: An observational study was performed at University of Maryland Medical System comparing Verigene Blood Culture (BC) to GenMark Dx ePlex Blood Culture ID (BCID) (Research Use Only) panels on blood cultures from adult patients. Positive percent agreement (PPA) between each RDT platform and Vitek MS was calculated for comparison of on-panel targets. Theoretical antimicrobial decisions were made based on RDT results, taking into consideration patient parameters, antimicrobial stewardship practices, and local infectious diseases epidemiology. DOOR-MAT with a partial credit scoring system was applied to these decisions and mean scores compared across platforms using paired t-test. Results: The study consisted of 160 unique patients. The Verigene BC PPA was 98.6% (95% CI 95.1, 99.8) and ePlex BCID PPA was 98% (95% CI 94.3, 99.6). Among the 31 organisms not on the Verigene BC panels, 61% were identified by the ePlex BCID Panels. The mean (standard deviation [SD]) DOOR-MAT score for Verigene BC was 86.8 (SD ± 28.5) versus ePlex BCID was 91.9 (SD ± 23.1), P = 0.01. Conclusion: Both RDT platforms had high PPA for on-panel targets. The ePlex BCID was able to identify more organisms than Verigene, resulting in higher mean DOOR-MAT scores.