TY - JOUR
T1 - Multicenter evaluation of the new etest gradient diffusion method for piperacillin-tazobactam susceptibility testing of enterobacterales, pseudomonas aeruginosa, and acinetobacter baumannii complex
AU - García-Fernández, Sergio
AU - Bala, Yohann
AU - Armstrong, Tom
AU - García-Castillo, María
AU - Burnham, Carey Ann D.
AU - Wallace, Meghan A.
AU - Hardy, Dwight
AU - Zambardi, Gilles
AU - Cantón, Rafael
N1 - Funding Information:
This study was funded by a research grant from bioMérieux (Marcy l’Etoile, France) and was partially supported by the Plan Estatal de I+D+i 2013–2016 and the Instituto de Salud Carlos III, Subdirección General de Redes y Centros de Investigación Coop-erativa, Ministerio de Economía, Industria y Competitividad, Spanish Network for Research in Infectious Diseases (grant RD16/0016/0011), cofinanced by the European Development Regional Fund (ERDF; A way to achieve Europe), Operative Program Intelligent Growth 2014 –2020. S.G.-F. is supported by a research contract from the Instituto de Salud Carlos III, Spain (Rio Hortega program, grant CM17/00033). Funding for the study performed at the Washington University study site was provided by bioMérieux.
Funding Information:
This study was funded by a research grant from bioM?rieux (Marcy l'Etoile, France) and was partially supported by the Plan Estatal de IDi 2013-2016 and the Instituto de Salud Carlos III, Subdirecci?n General de Redes y Centros de Investigaci?n Cooperativa, Ministerio de Econom?a, Industria y Competitividad, Spanish Network for Research in Infectious Diseases (grant RD16/0016/0011), cofinanced by the European Development Regional Fund (ERDF; A way to achieve Europe), Operative Program Intelligent Growth 2014-2020. S.G.-F. is supported by a research contract from the Instituto de Salud Carlos III, Spain (Rio Hortega program, grant CM17/00033). Funding for the study performed at the Washington University study site was provided by bioM?rieux.
Publisher Copyright:
Copyright © 2020 American Society for Microbiology. All Rights Reserved.
PY - 2020
Y1 - 2020
N2 - Piperacillin-tazobactam (P/T) is a β-lactam-β-lactamase inhibitor combination frequently used in the hospital setting. Etest is a gradient diffusion method that represents an alternative to broth microdilution (BMD) for performing antimicrobial susceptibility testing. We conducted a multicenter evaluation of the performance of the new P/T Etest compared to that of BMD following U.S. Food and Drug Administration (FDA) and International Standards Organization (ISO) standard ISO 20776-2 criteria using Clinical and Laboratory Standards Institute (CLSI)-FDA and European Committee on Antimicrobial Susceptibility Testing (EUCAST) interpretive breakpoints, respectively. A total of 977 isolates (775 Enterobacterales isolates, 119 Pseudomonas aeruginosa isolates, and 83 Acinetobacter baumannii complex isolates) were tested. Overall essential agreement (EA) was 96.4% and 96.6% for Enterobacterales when FDA and ISO 20776-2 criteria, respectively, were followed. EA was 98.3% for P. aeruginosa and 91.6% for the A. baumannii complex when both the FDA and ISO criteria were followed. Applying CLSI-FDA breakpoints, categorical agreement (CA) reached 93.0%, 93.3%, and 89.2% for the Enterobacterales, P. aeruginosa, and the A. baumannii complex, respectively. Two very major errors (VMEs; 1.1%) were found among the Enterobacterales (for 2 Klebsiella pneumoniae isolates). No additional major errors (MEs) or VMEs were found. Applying EUCAST breakpoints, CA was 94.8% and 95.8% for Enterobacterales and P. aeruginosa, respectively (no breakpoints are currently available for the A. baumannii complex). No VMEs were observed among the Enterobacterales, but 2 (0.4%) MEs were found. Among the P. aeruginosa isolates, 2 (6.9%) VMEs and 3 (3.3%) MEs were observed. These errors resulted when P/T Etest MICs were 1 doubling dilution apart from the BMD MICs. In conclusion, the new P/T Etest represents an accurate tool for performing antimicrobial susceptibility testing of Enterobacterales, P. aeruginosa, and A. baumannii complex isolates with limited category errors.
AB - Piperacillin-tazobactam (P/T) is a β-lactam-β-lactamase inhibitor combination frequently used in the hospital setting. Etest is a gradient diffusion method that represents an alternative to broth microdilution (BMD) for performing antimicrobial susceptibility testing. We conducted a multicenter evaluation of the performance of the new P/T Etest compared to that of BMD following U.S. Food and Drug Administration (FDA) and International Standards Organization (ISO) standard ISO 20776-2 criteria using Clinical and Laboratory Standards Institute (CLSI)-FDA and European Committee on Antimicrobial Susceptibility Testing (EUCAST) interpretive breakpoints, respectively. A total of 977 isolates (775 Enterobacterales isolates, 119 Pseudomonas aeruginosa isolates, and 83 Acinetobacter baumannii complex isolates) were tested. Overall essential agreement (EA) was 96.4% and 96.6% for Enterobacterales when FDA and ISO 20776-2 criteria, respectively, were followed. EA was 98.3% for P. aeruginosa and 91.6% for the A. baumannii complex when both the FDA and ISO criteria were followed. Applying CLSI-FDA breakpoints, categorical agreement (CA) reached 93.0%, 93.3%, and 89.2% for the Enterobacterales, P. aeruginosa, and the A. baumannii complex, respectively. Two very major errors (VMEs; 1.1%) were found among the Enterobacterales (for 2 Klebsiella pneumoniae isolates). No additional major errors (MEs) or VMEs were found. Applying EUCAST breakpoints, CA was 94.8% and 95.8% for Enterobacterales and P. aeruginosa, respectively (no breakpoints are currently available for the A. baumannii complex). No VMEs were observed among the Enterobacterales, but 2 (0.4%) MEs were found. Among the P. aeruginosa isolates, 2 (6.9%) VMEs and 3 (3.3%) MEs were observed. These errors resulted when P/T Etest MICs were 1 doubling dilution apart from the BMD MICs. In conclusion, the new P/T Etest represents an accurate tool for performing antimicrobial susceptibility testing of Enterobacterales, P. aeruginosa, and A. baumannii complex isolates with limited category errors.
KW - Acinetobacter baumannii complex
KW - Antimicrobial susceptibility testing
KW - Enterobacterales
KW - Etest
KW - Gradient diffusion
KW - Piperacillin-tazobactam
KW - Pseudomonas aeruginosa
UR - http://www.scopus.com/inward/record.url?scp=85078684152&partnerID=8YFLogxK
U2 - 10.1128/JCM.01042-19
DO - 10.1128/JCM.01042-19
M3 - Article
C2 - 31597745
AN - SCOPUS:85078684152
VL - 58
JO - Journal of Clinical Microbiology
JF - Journal of Clinical Microbiology
SN - 0095-1137
IS - 2
M1 - e01042-19
ER -