Impact of an Antimicrobial Stewardship Program-bundled initiative utilizing Accelerate Pheno™ system in the management of patients with aerobic Gram-negative bacilli bacteremia



Gram-negative bacteria (GNB) are a leading cause of bloodstream infections (BSI) and management is complicated by antibiotic resistance. The Accelerate Pheno™ system (ACC) can provide rapid organism identification and antimicrobial susceptibility testing (AST).


A retrospective, pre-intervention/post-intervention study was conducted to compare management of non-critically ill patients with GNB BSI before and after implementation of a bundled initiative. This bundled initiative included dissemination of a clinical decision algorithm, ACC testing on all GNB isolated from blood cultures, real-time communication of results to the Antimicrobial Stewardship Program (ASP), and prospective audit with feedback by the ASP. The pre-intervention period was January 2018 through December 2018, and the post-intervention period was May 2019 through February 2020.


Seventy-seven and 129 patients were included in the pre-intervention and post-intervention cohorts, respectively. When compared with the pre-intervention group, the time from Gram stain to AST decreased from 46.1 to 6.9 h (p < 0.001), and the time to definitive therapy (TTDT) improved from 32.6 to 10.5 h (p < 0.001). Implementation led to shorter median total duration of antibiotic therapy (14.2 vs 9.5 days; p < 0.001) and mean hospital length of stay (7.9 vs 5.3 days; p = 0.047) without an increase in 30-day readmissions (22.1% vs 14%; p = 0.13).


Implementation of an ASP-bundled approach incorporating the ACC aimed at optimizing antibiotic therapy in the management GNB BSI in non-critically ill patients led to reduced TTDT, shorter duration of antibiotic therapy, and shorter hospital length of stay without adversely affecting readmission rates.

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The authors wish to thank the microbiology technicians at the Allegheny Health Network microbiology laboratory for their support and dedication in the utilization and optimization of the Accelerate PhenoTM System



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Correspondence to Thomas L. Walsh or Matthew A. Moffa.

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Conflict of interest

TLW has received consulting fees from Accelerate Diagnostics. DC has received speaking honoraria from Merck. All the other authors report no conflict of interest relating to the current study.

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Walsh, T.L., Bremmer, D.N., Moffa, M.A. et al. Impact of an Antimicrobial Stewardship Program-bundled initiative utilizing Accelerate Pheno™ system in the management of patients with aerobic Gram-negative bacilli bacteremia. Infection (2021).

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  • Rapid diagnostic testing
  • Accelerate Pheno™
  • Gram-negative bacteremia
  • Bloodstream infection
  • Antimicrobial stewardship