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Published on: October 8, 2021
Simultaneous three Enterobacteriaceae with different bla NDM-1-encoding plasmids in a patient transferred from
Chih-Cheng Lai1, Chi-Chung Chen2,3, Ying-Chen Lu3
1Department of Intensive Care Medicine, Chi Mei Medical Center, Liouying, Tainan, Taiwan.
Abstract:
New-Delhi metallo-β-lactamase1 (NDM-1) Enterobacteriaceae are increasing worldwide. Herein, we describe a single patient who carried three unusual NDM-1 carbapenem-resistant Enterobacteriaceae - Enterobacter cloacae (E. cloacae) yielded from a urine specimen and Klebsiella pneumoniae (K. pneumoniae) and Escherichia coli (E. coli) from stool specimens. For E. cloacae, its bla NDM-1-encoding plasmid was pKP04NDM with a size of ~54 kb replicons with an IncN backbone. For K. pneumoniae, its bla NDM-1-encoding plasmid was pNDM-BTR with a size of ~59.6 kb and belonged to IncN. For E. coli, its main bla NDM-1-encoding plasmid was pIMP-HK1500, and the NDM-1 gene was obtained from a part of pNDM-BTR (8439 bp). These three clinical strains are reported for the first time and are assumed to be imported from mainland China to Taiwan. The three different plasmids were never reported in K. pneumoniae, E. coli, and Citrobacter spp before. Owing to their associated multidrug resistance, appropriate measures of periodic, targeted surveillance, and development of new antimicrobial agents are urgently needed.
Insights
Three unusual New-Delhi metallo-β-lactamase1 (NDM-1) carbapenem-resistant Enterobacteriaceae strains were identified in a single patient. These multidrug-resistant bacteria highlight the urgent need for enhanced surveillance and new antimicrobial agents.
Area of Science:
- Medical Microbiology
- Infectious Diseases
- Antimicrobial Resistance
Background:
- New-Delhi metallo-β-lactamase1 (NDM-1) producing Enterobacteriaceae are a growing global health concern.
- Carbapenem resistance in Enterobacteriaceae poses significant treatment challenges.
Purpose of the Study:
- To report a unique case of a single patient carrying three distinct NDM-1 carbapenem-resistant Enterobacteriaceae strains.
- To characterize the plasmids encoding the NDM-1 gene in these clinical isolates.
- To emphasize the need for surveillance and development of new antimicrobial strategies.
Main Methods:
- Clinical isolates of Enterobacter cloacae, Klebsiella pneumoniae, and Escherichia coli were obtained from urine and stool specimens.
- Plasmid analysis was performed to identify and characterize the blaNDM-1 encoding plasmids.
- Genetic relatedness of plasmids was investigated.
Main Results:
- Three unusual NDM-1 carbapenem-resistant Enterobacteriaceae strains (E. cloacae, K. pneumoniae, E. coli) were identified in one patient.
- Characterization revealed distinct plasmids: pKP04NDM (~54 kb, IncN) in E. cloacae, pNDM-BTR (~59.6 kb, IncN) in K. pneumoniae, and pIMP-HK1500 in E. coli.
- The NDM-1 gene in E. coli was found within a fragment of pNDM-BTR, indicating potential plasmid sharing or rearrangement.
- These plasmids were novel in K. pneumoniae, E. coli, and Citrobacter spp.
Conclusions:
- The co-occurrence of three different NDM-1 Enterobacteriaceae strains in a single patient is highly unusual and suggests potential importation from mainland China to Taiwan.
- The identification of novel plasmids associated with multidrug resistance underscores the dynamic nature of antimicrobial resistance.
- Urgent implementation of periodic, targeted surveillance and the development of novel antimicrobial agents are crucial to combat the spread of NDM-1 producing Enterobacteriaceae.
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