Clinical and Molecular Characteristics of Patients with Bloodstream Infections Caused by KPC and NDM Co-Producing Carbapenem-Resistant Klebsiella pneumoniae

Abstract

Purpose

Klebsiella pneumoniae carbapenemase (KPC) and New Delhi metallo-β-lactamase (NDM) co-producing carbapenem-resistant Klebsiella pneumoniae (KPC-NDM-CRKP) isolates have been increasingly reported worldwide but have not yet been systematically studied. Thus, we have conducted a study to compare the risk factors, molecular characteristics, and mortality involved in clinical bloodstream infections (BSIs) caused by KPC-NDM-CRKP and KPC-CRKP strains.

Methods

A retrospective study was conducted on 231 patients with BSIs caused by CRKP at Jinling Hospital in China from January 2020 to December 2022. Antimicrobial susceptibility testing, carbapenemase genes detection and whole-genome sequencing were performed subsequently.

Results

Overall, 231 patients were included in this study: 25 patients with KPC-NDM-CRKP BSIs and 206 patients with KPC-CRKP BSIs. Multivariate analysis implicated ICU-acquired BSI, surgery within 30 days, and longer stay of hospitalization prior to CRKP isolation as independent risk factors for KPC-NDM-CRKP BSIs. The 30-day mortality rate of the KPC-NDM-CRKP BSIs group was 56% (14/25) compared with 32.5% (67/206) in the KPC-CRKP BSIs control group (P = 0.02). The ICU-acquired BSIs, APACHE II score at BSI onset, and BSIs caused by KPC-NDM-CRKP were independent predictors for 30-day mortality in patients with CRKP bacteremia. The most prevalent ST in KPC-NDM-CRKP isolates was ST11 (23/25, 92%), followed by ST15 (2/25, 8%).

Conclusion

In patients with CRKP BSIs, KPC-NDM-CRKP was associated with an excess of mortality. The likelihood that KPC-NDM-CRKP will become the next “superbug” highlights the significance of epidemiologic surveillance and clinical awareness of this pathogen.

Keywords:

• KPC and NDM co-producing carbapenem-resistant Klebsiella pneumoniae
• Bloodstream infections
• risk factors
• molecular characteristics
• mortality

Ethics Approval and Informed Consent

This retrospective study was conducted in accordance with the ethical standards of the Institutional Review Board Ethics Committee of Jinling Hospital (2022DZSKT-007) and the Declaration of Helsinki and national and institutional standards. The requirement to obtain informed written consent was waived because the biometric information and data in this study have been de-identified, and any information obtained during the investigation will be treated with the utmost confidentiality.

Disclosure

The authors report no conflicts of interest in this work.

Additional information

Funding

This work was supported by the National Natural Science Foundation of China (grant number 82272237), Jiangsu Provincial Medical Innovation Center (grant number CXZX202217), and Key Research and Development Program of Jiangsu Province (grant number BE2022823).