Three Novel Sequence Types Carbapenem-Resistant Klebsiella pneumoniae Strains ST5365, ST5587, ST5647 Isolated from Two Tertiary Teaching General Hospitals in Shanxi Province, in North China: Molecular Characteristics, Resistance and Virulence Factors

Yujie Liu; Jing Bai; Jianbang Kang; Yan Song; Donghong Yin; Jing Wang; Hao Li; Jinju Duan

doi:10.2147/IDR.S366480

Three Novel Sequence Types Carbapenem-Resistant Klebsiella pneumoniae Strains ST5365, ST5587, ST5647 Isolated from Two Tertiary Teaching General Hospitals in Shanxi Province, in North China: Molecular Characteristics, Resistance and Virulence Factors

Infect Drug Resist. 2022 May 18:15:2551-2563. doi: 10.2147/IDR.S366480. eCollection 2022.

Authors

Yujie Liu^#¹, Jing Bai^#¹, Jianbang Kang², Yan Song², Donghong Yin², Jing Wang², Hao Li³, Jinju Duan²

Affiliations

¹ Department of Pharmacy, School of Pharmacy, Shanxi Medical University, Taiyuan, Shanxi, People's Republic of China.
² Department of Pharmacy, Second Hospital of Shanxi Medical University, Taiyuan, Shanxi, People's Republic of China.
³ Department of Clinical Laboratory, First Hospital of Shanxi Medical University, Taiyuan, Shanxi, People's Republic of China.

^# Contributed equally.

Abstract

Background: Carbapenem-resistant Klebsiella pneumoniae (CRKP) represents a significant threat to public health and has already drawn worldwide attention. Hence, we aim to comprehensively analyze the case condition, as well as molecular epidemiology, resistance and virulence of three CRKP isolates with new sequence types (STs).

Methods: Three CRKP were collected from November 2019 to April 2021. The three patients' clinical characteristics were analyzed through His system. In order to screen phenotype of metallo-carbapenemase, the modified Carbapenem Inactivation Method (mCIM) and EDTA-modified Carbapenem Inactivation Method (eCIM) were conducted. Three isolates were subjected to antimicrobial susceptibility testing (AST) using the agar dilution method or minimal broth dilution method. The string test, the sedimentation assay, biofilm formation and the serum resistance assay were performed as phenotypic experiments to assist in evaluating virulence. The presence of resistance and virulence genes were detected by Whole-Genome Sequencing (WGS). Serotypes and new STs were compared and determined by multi-locus sequence typing (MLST).

Results: Overall, all Klebsiella pneumoniae isolates were multi-resistant, but sensitive to tigecycline and colistin. Among them, all formed biofilms, strain 1 and strain 2 were classified as moderate-producers, while strain 3 as weak-producer. The results of the serum resistance assay indicated that only strain 2 was resistant. From WGS analysis, it showed that all isolates co-harbored multiple resistance genes, such as carbapenemase genes, sulfonamides, fluoroquinolones, aminoglycosides, and tetracyclines. Meanwhile, several virulence genes were also contained, including siderophores, fimbriae, capsule and lipopolysaccharides-associated genes. The serotypes of strain 1 and strain 2 manifested K35 and KL47, respectively.

Conclusion: Three novel ST5365, ST5587, ST5647 were first discovered in North China. Our study suggested that we should pay more attention to their resistance. And the results will help treat CRKP infections caused by these novel STs.

Keywords: CRKP; carbapenem-resistant Klebsiella pneumoniae; molecular characteristics; new sequence types; resistance; virulence factors.

Grants and funding

This work was supported by the Shanxi Province Natural Science Foundation (grant number 201803D31124). The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.