Performance evaluation of the UMIC® Cefiderocol to determine MIC in Gram-negative bacteria.
J Antimicrob Chemother
; 78(7): 1672-1676, 2023 07 05.
Article
em En
| MEDLINE
| ID: mdl-37209112
ABSTRACT
BACKGROUND:
Cefiderocol is a catechol-substituted cephalosporin with potent in vitro activity against carbapenem-resistant (CR) Gram-negative bacteria (GNB). Cefiderocol susceptibility testing is complex because iron concentrations need to be taken into consideration. Here, we assessed the clinical performance of Bruker's UMIC® Cefiderocol and corresponding iron-depleted CAMHB to determine MIC by broth microdilution (BMD) for clinically relevant GNB.METHODS:
MICs of cefiderocol for 283 GN clinical isolates were determined by BMD using iron-depleted CAMHB. Frozen panels were used as a reference. The concentration range of cefiderocol was 0.03-32 mg/L. The isolates, with different degrees of susceptibility to cefiderocol, included Enterobacterales (nâ=â180), Pseudomonas aeruginosa (nâ=â49), Acinetobacter baumannii (nâ=â44) and Stenotrophomonas maltophilia (nâ=â10).RESULTS:
The rates of categorical agreement (CA), essential agreement (EA) and bias were calculated to evaluate the performance of the UMIC® Cefiderocol, as compared with the reference method. Overall, the UMIC® Cefiderocol showed 90.8% EA (95% CI 86.9%-93.7%) with a bias of -14.5% and a CA of 90.1% (95% CI 86.1%-93.1%). For Enterobacterales, the UMIC® Cefiderocol showed 91.7% EA (95% CI 86.7%-94.9%) with a bias of -25.0% and a CA of 87.8% (95% CI 82.2%-91.8%). For non-fermenters, the UMIC® Cefiderocol showed 89.3% EA (95% CI 81.9%-93.9%) (not significantly different from 90.0%, Student t-test) with a bias of -3.9% and a CA of 94.2% (95% CI 87.7%-97.3%).CONCLUSIONS:
UMIC® Cefiderocol is a valid method for the determination of cefiderocol MICs even if higher than expected discrepancies were observed with NDM-producing Enterobacterales, which presented in most cases MIC values close to the breakpoint.
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Cefalosporinas
/
Antibacterianos
Limite:
Humans
Idioma:
En
Ano de publicação:
2023
Tipo de documento:
Article