Clinical and Molecular Characteristics of Carbapenem-Resistant Hypervirulent Klebsiella pneumoniae Isolates in a Tertiary Hospital in Shanghai, China

Abstract

Background

The convergence of carbapenem-resistance and hypervirulence in Klebsiella pneumoniae has led to a significant public health challenge. In recent years, there have been more and more reports on carbapenem-resistant hypervirulent Klebsiella pneumoniae (CR-hvKP) isolates.

Materials and Methods

Clinical data of patients infected with CR-hvKP from January 2019 to December 2020 in a tertiary hospital were retrospectively evaluated. The number of isolates of Klebsiella pneumoniae, hypermucoviscous Klebsiella pneumoniae (hmKP), carbapenem-resistant hypermucoviscous Klebsiella pneumoniae (CR-hmKP) and carbapenem-resistant hypervirulent Klebsiella pneumoniae (CR-hvKP) collected during the period of 2 years was calculated. The antimicrobial resistance gene, virulence-associated gene, capsular serotype gene and multilocus sequence typing (MLST) of CR-hvKP isolates were detected by PCR.

Results

During the study period, a total of 1081 isolates of non-repeat Klebsiella pneumoniae were isolated, including 392 isolates of hypermucoviscous Klebsiella pneumoniae (36.3%), 39 isolates of CR-hmKP (3.6%), and 16 isolates of CR-hvKP (1.5%). About 31.2% (5/16) of CR-hvKP were isolated from 2019, and 68.8% (11/16) of CR-hvKP were isolated from 2020. Among the 16 isolates of CR-hvKP, 13 isolates were ST11 and serotype K64, 1 isolate was ST11 and serotype K47, 1 isolate was ST23 and serotype K1, and 1 isolate was ST86 and serotype K2. The virulence-associated genes entB, fimH, rmpA2, iutA, iucA were present in all of 16 CR-hvKP isolates, followed by mrkD (n=14), rmpA (n=13), aerobactin (n=2), allS (n=1). Sixteen CR-hvKP isolates all carry carbapenemase gene bla_KPC-2 and extended-spectrum β-lactamase gene bla_SHV. ERIC-PCR DNA fingerprinting results showed that 16 CR-hvKP isolates were highly polymorphic, and there were significant differences in bands among the isolates, presenting a sporadic state.

Conclusion

Although CR-hvKP was sporadically distributed, it showed an increasing trend year by year. Therefore, clinical attention should be paid, and necessary measures should be taken to avoid the cloning and transmission of superbacterium CR-hvKP.

Keywords:

• Klebsiella pneumoniae
• carbapenem-resistant
• hypervirulent
• hypermucoviscous
• epidemiology

Acknowledgments

We thank all the staff of the Central Laboratory of Shanghai Fifth People’s Hospital for their technical guidance in this study.

Ethics Approval and Informed Consent

The medical ethics council of Shanghai Fifth People’s Hospital approved this study (Approval No. 104, 2020). The clinical samples were part of the routine hospital laboratory procedure.

Disclosure

The authors report no conflicts of interest in this work.