P-1286. In vitro Activity of Cefiderocol against Carbapenem-nonsusceptible Acinetobacter baumannii-calcoaceticus complex, Including Molecularly Characterized Clinical Isolates, Causing Infections in United States Hospitals (2020–2024)
In vitro testing shows cefiderocol effectiveness against multidrug-resistant Acinetobacter, indicating a treatment option for carbapenem-resistant infections.
Key Points
To evaluate the in vitro activity of cefiderocol against carbapenem-nonS Acinetobacter baumannii-calcoaceticus complex isolates.
Collected 1,999 ACB isolates from 76 US hospitals (2020-2024)
Performed susceptibility testing using broth microdilution methods
Screened for β-lactamase genes in resistant isolates
29.4% of isolates were carbapenem-nonS, with carbapenemase genes in 86.4% of those
Cefiderocol showed 92.9-97.7% susceptibility with MIC50 of 0.12 mg/L and MIC90 of 1 mg/L
Limited activity from β-lactam comparators (66.8-72.0% susceptibility)