Scientific Letters
Vol. 18 No. 1 (2026): Mediterranean Journal of Hematology and Infectious Diseases
Successful Treatment with Imipenem/Cilastatin/Relebactam of a Polymicrobial Bacteremia due to Meropenem/Vaborbactam-Resistant KPC-Producing Klebsiella pneumoniae and Enterococcus faecalis
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All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article or claim that may be made by its manufacturer is not guaranteed or endorsed by the publisher.
Published: April 30, 2026
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Dear Editor,
Carbapenemase-producing Klebsiella pneumoniae (KPC-Kp) remains a major global health challenge, associated with high mortality and limited therapeutic options [1,2]. Although novel β-lactam/β-lactamase inhibitor combinations (BL/BLI), such as meropenem/vaborbactam (M/V), have improved treatment outcomes, M/V-resistance is increasingly reported, often due to porin alterations or overexpression of blaKPC genes [2,4,7]. Imipenem/cilastatin/relebactam (IMI/REL) represents an alternative strategy, combining a carbapenem with a potent class A/C β-lactamase inhibitor that can restore activity against certain carbapenemase-producing strains [3–6].
Herein, we describe the first documented case of successful treatment of a polymicrobial bloodstream infection caused by M/V-resistant but IMI/REL-susceptible KPC-Kp, with concomitant Enterococcus faecalis, in an elderly, frail patient.
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Citations
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KPC, Imipenem/Cilastatin/Relebactam , Meropenem/Vaborbactam, Antimicrobial resistance, sepsisHow to Cite
“Successful Treatment with Imipenem/Cilastatin/Relebactam of a Polymicrobial Bacteremia due to Meropenem/Vaborbactam-Resistant KPC-Producing Klebsiella pneumoniae and Enterococcus faecalis” (2026) Mediterranean Journal of Hematology and Infectious Diseases, 18(1), p. e2026037. doi:10.4084/MJHID.2026.037.
Copyright (c) 2026 Federico Marzi, Mario Alessandri, Veronica De Crescenzo, Stefania Del Vecchio, Simone Radi, Maurizio Manini
This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.
