Pérez-Rodríguez, GloriaAja-Macaya, PabloGonzález-Pinto, LucíaTaltavull, BielTarriño-León, MaríaGallardo-García, María del MarBlanco Martín, TaniaRodríguez-Pallares, SaludSánchez-Peña, LucíaMoscoso, MiriamBeceiro Casas, AlejandroOliver, AntonioBou, GermánArca-Suárez, Jorge2026-05-252026-05-252026-03-27Pérez-Rodríguez G, Aja-Macaya P, González-Pinto L, Taltavull B, Tarriño-León M, Gallardo-García MdM, Blanco-Martín T, Rodríguez-Pallares S, Sánchez-Peña L, Moscoso M, Beceiro A, Oliver A, Bou G, Arca-Suárez J. Emergence of KPC-producing Pseudomonas aeruginosa in Spain: insights into an outbreak and resistance to the novel carbapenem/β-lactamase inhibitor combinations imipenem/relebactam and meropenem/vaborbactam. Antimicrob Agents Chemother. 2026 May 6;70(5):e0165725.1098-6596https://hdl.handle.net/2183/48365[Abstract] We report an outbreak of KPC-producing Pseudomonas aeruginosa in Spain, involving four patients and an environmental isolate recovered from a hospital sink. All isolates belonged to clone ST253 and exhibited difficult-to-treat resistance, including resistance to imipenem/relebactam and meropenem/vaborbactam. Genomic analysis confirmed a plasmid-encoded blaKPC-2 and OprD deficiency. Functional assays demonstrated synergy between KPC-2 production and porin loss on resistance to carbapenem/β-lactamase inhibitors. The findings highlight the clinical threat posed by KPC-producing P. aeruginosa.engAttribution 4.0 Internationalhttp://creativecommons.org/licenses/by/4.0/KPCPseudomonas aeruginosaCarbapenemCarbapenemaseImipenem/relebactamMeropenem/vaborbactamMutational mechanismsβ-lactam resistanceβ-lactamaseβ-lactamase inhibitorjournal articleopen access10.1128/AAC.01657-25