Nosocomial outbreak by NDM-1-producing Klebsiella pneumoniae highly resistant to cefiderocol, Florence, Italy, August 2021 to June 2022

Coppi, Marco; Antonelli, Alberto; Niccolai, Claudia; Bartolini, Andrea; Bartolini, Laura; Grazzini, Maddalena; Mantengoli, Elisabetta; Farese, Alberto; Pieralli, Filippo; Mechi, Maria Teresa; Di Pilato, Vincenzo; Giani, Tommaso; Rossolini, Gian Maria

doi:10.2807/1560-7917.ES.2022.27.43.2200795

A nosocomial outbreak by cefiderocol (FDC)-resistant NDM-1-producing Klebsiella pneumoniae (NDM-Kp) occurred in a large tertiary care hospital from August 2021-June 2022 in Florence, Italy, an area where NDM-Kp strains have become endemic. Retrospective analysis of NDM-Kp from cases observed in January 2021-June 2022 revealed that 21/52 were FDC-resistant. The outbreak was mostly sustained by clonal expansion of a mutant with inactivated cirA siderophore receptor gene, which exhibited high-level resistance to FDC (MIC ≥ 32 mg/L) and spread independently of FDC exposure.

Nosocomial outbreak by NDM-1-producing Klebsiella pneumoniae highly resistant to cefiderocol, Florence, Italy, August 2021 to June 2022 / Coppi, Marco; Antonelli, Alberto; Niccolai, Claudia; Bartolini, Andrea; Bartolini, Laura; Grazzini, Maddalena; Mantengoli, Elisabetta; Farese, Alberto; Pieralli, Filippo; Mechi, Maria Teresa; Di Pilato, Vincenzo; Giani, Tommaso; Rossolini, Gian Maria. - In: EUROSURVEILLANCE. - ISSN 1560-7917. - ELETTRONICO. - 27:(2022), pp. 0-0. [10.2807/1560-7917.ES.2022.27.43.2200795]