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Volume 32, Number 6—June 2026

Synopsis

Emergence of Klebsiella pneumoniae Carbapenemase–Producing K. pneumoniae with Penicillin-Binding Protein 3 Insertions, Taiwan, 2021

Tengfei Long, Arianne Lovey, Lillie Sanborn, Yanan Zhao, Zackery P. Bulman, Yi-Tsung LinComments to Author , and Liang ChenComments to Author 
Author affiliation: School of Pharmacy and Pharmaceutical Sciences, University at Buffalo, Buffalo, New York, USA (T. Long, A. Lovey, L. Sanborn, Y. Zhao, L. Chen); Retzky College of Pharmacy, University of Illinois Chicago, Chicago, Illinois, USA (Z.P. Bulman); Centre for Infection Control and Division of Infectious Diseases, Department of Medicine, Taipei Veterans General Hospital, Taipei, Taiwan (Y.-T. Lin); Institute of Emergency and Critical Care Medicine, National Yang Ming Chiao Tung University, Taipei (Y.-T. Lin)

Main Article

Table

Antimicrobial susceptibility of isolates from a study of emergence of Klebsiella pneumoniae carbapenemase-producing K. pneumoniae with PBP3 insertions, Taiwan, 2021*

Strain bla plasmids MIC, µg/mL†
IMP MEM CAZ ATM CAZ/AVI ATM/AVI IMP/REL MEM/VBR CFDC
LC1489 blaKPC-2, blaSHV-11, blaTEM-1, blaDHA-1 128 >128 >128 >128 8 8 0.5 2 0.5
LC1490 blaKPC-2, blaSHV-11, blaTEM-1, blaDHA-1 128 >128 >128 >128 8 8 0.25 1 0.5
LC1491
 blaSHV-11, blaKPC-2
 128
 >128
 >128
 >128
 4
 1
 0.5
 2
 0.25
ΔpKPC
LC1489 blaSHV-11, blaTEM-1, blaDHA-1 2 2 >128 16 4 2 0.25 0.25 0.06
LC1490 blaSHV-11, blaTEM-1, blaDHA-1 2 2 >128 32 4 4 0.25 0.25 0.06
LC1491
 blaSHV-11
 0.25
 1
 4
 2
 1
 1
 0.5
 0.25
 0.06
LC1491 derivative‡
LC2124, KPC-21a blaSHV-11, blaKPC-21 32 >128 >128 >128 32 >128 2 4 1
LC2125, KPC-21b blaSHV-11, blaKPC-21 32 >128 >128 >128 16 >128 2 4 0.5
LC2126, KPC-21c
 blaSHV-11, blaKPC-21
 32
 >128
 >128
 >128
 32
 >128
 2
 4
 1
ΔpKPC-pUC-NDM§
LC1489 blaNDM-1, blaSHV-11, blaTEM-1, blaDHA-1 >128 >128 >128 64 >128 4 >128 >128 32
LC1490 blaNDM-1, blaSHV-11, blaTEM-1, blaDHA-1 >128 >128 >128 64 >128 4 >128 >128 32
LC1491 blaNDM-1, blaSHV-11 >128 >128 >128 4 >128 1 >128 >128 32

*All isolates had PBP3 insertion YRIT, OmpK35 with a premature stop codon at amino acid position 63, and OmpK36 with a glycine–aspartate insertion at amino acid position 134 GD. Bold indicates nonsusceptibility. ΔpKPC, blaKPC-2 plasmid-cured mutants; ATM, aztreonam; ATM/AVI, aztreonam/avibactam; CAZ, ceftazidime; CAZ/AVI, ceftazidime/avibactam; CFDC, cefiderocol; IMP, imipenem; IMP/REL, imipenem/relebactam; KPC, Klebsiella pneumoniae carbapenemase; MEM, meropenem; MEM/VBR, meropenem/vaborbactam; NDM, New Dehli metallo-β-lactamase; PBP3, penicillin-binding protein 3. †Susceptibility determined on the basis of Clinical and Laboratory Standards Institute 2025 breakpoints (16), except for ATM/AVI, for which we used EUCAST breakpoint (>4 μg/mL). ‡Selected KPC-21 mutant strains obtained through an in vitro selection experiment. §blaKPC-2 plasmid-cured mutants carrying a pUC-blaNDM-1 vector.

Main Article

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