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Carbapenem-Resistant Enterobacterales: Considerations for Treatment in the Era of New Antimicrobials and Evolving Enzymology


Purpose of Review

Gram-negative resistance is a growing concern globally. Enterobacterales, formerly Enterobacteriaceae, have developed resistance mechanisms to carbapenems that leave very few antimicrobial options in the clinician’s armamentarium.

Recent Findings

New antimicrobials like ceftazidime-avibactam, meropenem-vaborbactam, imipenem-relebactam, cefiderocol, and plazomicin have the potential to overcome resistance mechanisms in Enterobacterales including different classes of carbapenemases.


Novel β-lactam/β-lactamase inhibitors, plazomicin, and cefiderocol give the clinician options that were once not available. Utilizing these options is of the utmost importance when treating carbapenem-resistant Enterobacterales.

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Correspondence to David P. Nicolau.

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DPN is a consultant, speaker’s bureau member, or have received research funding from Allergan, Bayer, Cepheid, Merck, Melinta, Pfizer, Wockhardt, Shionogi, and Tetraphase.

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Lasko, M.J., Nicolau, D.P. Carbapenem-Resistant Enterobacterales: Considerations for Treatment in the Era of New Antimicrobials and Evolving Enzymology. Curr Infect Dis Rep 22, 6 (2020).

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  • Resistance
  • Carbapenemase
  • Enterobacterales
  • Enterobacteriaceae