Jack G Schneider1, James B Wood2, Nathan W Smith3, Christopher L Emery4, Thomas E Davis4, John J Manaloor2, Brittany Bocian5, Bryan H Schmitt4. 1. Ryan White Center for Pediatric Infectious Diseases and Global Health, Indiana University School of Medicine, Indianapolis, Indiana, USA. Electronic address: jgschnei@iu.edu. 2. Ryan White Center for Pediatric Infectious Diseases and Global Health, Indiana University School of Medicine, Indianapolis, Indiana, USA. 3. Accelerate Diagnostics, Inc., Tucson, AZ, USA. 4. Department of Pathology and Laboratory Medicine, Indiana University School of Medicine, Indianapolis, Indiana, USA. 5. Indiana University Health Methodist and University Hospitals, Indianapolis, Indiana, USA.
Abstract
OBJECTIVES: To compare the performance and time-to-result (TTR) for antimicrobial susceptibility testing (AST) of positive blood cultures (PBC) using the Accelerate Pheno™ system (AXDX) and both a direct VITEK® 2 card inoculation workflow (DV2) and traditional FDA-approved VITEK® 2 workflow using subcultured isolates (V2). METHODS: Patient samples with monomicrobial Gram-negative rod bacteremia were tested on AXDX and DV2 in tandem and compared to V2 AST results. Categorical agreement (CA) errors were adjudicated using broth microdilution. Instrumentation times and AST TTR were compared. RESULTS: AXDX and DV2 had a CA of 93.4% and 97.4%, respectively, compared to V2. Postadjudication, AXDX, DV2, and V2 had CA of 94.7%, 95.7%, and 96.5%, respectively. Instrument run times were 6.6 h, 9.4 h, and 9.2 h, and AST TTR were 8.9 h, 12.9 h and 35.5 h, respectively. CONCLUSIONS: AXDX and DV2 ASTs are fast and reliable, which may have significant antimicrobial stewardship implications.
OBJECTIVES: To compare the performance and time-to-result (TTR) for antimicrobial susceptibility testing (AST) of positive blood cultures (PBC) using the Accelerate Pheno™ system (AXDX) and both a direct VITEK® 2 card inoculation workflow (DV2) and traditional FDA-approved VITEK® 2 workflow using subcultured isolates (V2). METHODS:Patient samples with monomicrobial Gram-negative rod bacteremia were tested on AXDX and DV2 in tandem and compared to V2 AST results. Categorical agreement (CA) errors were adjudicated using broth microdilution. Instrumentation times and AST TTR were compared. RESULTS:AXDX and DV2 had a CA of 93.4% and 97.4%, respectively, compared to V2. Postadjudication, AXDX, DV2, and V2 had CA of 94.7%, 95.7%, and 96.5%, respectively. Instrument run times were 6.6 h, 9.4 h, and 9.2 h, and AST TTR were 8.9 h, 12.9 h and 35.5 h, respectively. CONCLUSIONS:AXDX and DV2 ASTs are fast and reliable, which may have significant antimicrobial stewardship implications.
Authors: Michael R Jacobs; Caryn E Good; Ayman M Abdelhamed; Robert A Bonomo Journal: Antimicrob Agents Chemother Date: 2022-01-31 Impact factor: 5.191