Analysis of Carbapenemase-Resistant Genotypes of Highly Virulent Klebsiella pneumoniae and Clinical Infection Characteristics of Different MLST Types.

Shuli Liu,Qiu Zhao,Xiangbing Wu,Yue Man Li,Jingjing Ge,Xiaobo Wang,Renshu Wang,Songwen Tan

doi:10.1155/2021/3455121

Abstract

Carbapenemase-resistant Klebsiella pneumoniae (CR-KP) has become one of the nosocomial infections that seriously threaten the lives of patients, greatly increasing the burden on patients. In order to explore the resistance mechanism of clinically isolated CR-KP to carbapenems and perform multilocus sequence typing (MLST), to study the clinical characteristics of patients with different ST types of infection, we collected 74 CR-KP strains clinically isolated from the main 6 hospitals in Zhejiang province from January 2018 to July 2020. The sensitivity of the tested strains to 23 antibacterial drugs was determined by the microbroth dilution method, and PCR was applied. Gene amplification technology and DNA sequencing methods were used to detect the carbapenemase gene of the tested strains. Through the MLST of the tested strains, the clonal correlation and molecular epidemiological characteristics of the tested strains were explored, and the characteristics of CR-KP resistance, resistance mechanisms, and clinical characteristics of bacterial infections under different MLST types were analyzed at the same time. The results showed that 74 carbapenem-resistant Klebsiella pneumoniae strains showed high resistance to 21 commonly used antibacterial drugs, and all carbapenemase phenotypic screening tests were positive. MLST typing showed that 74 CR-KP strains had 17 ST typings, and ST11 was the dominant type (54.05%). The study also found that these ST11 strains are more likely to be resistant to carbapenem antibiotics. Most of them produce KPC carbapenemase, and a few are IMP, VIM, and NDM. Univariate analysis suggested that the proportion of patients in the ST11 group receiving treatment in ICU, the use rate of mechanical ventilation, and the proportion of drainage tube indwelling were higher than those in the non-ST11 group, and the survival rate of the ST11 group was lower than that of the non-ST11 group. Clinical data suggested that the same hospital was dominated by the same clonal epidemic in the same period. In view of the analysis of clinical data suggesting that patients who have received ICU treatment, mechanical ventilation, and drainage tube indwelling are prone to the risk of CR-KP strain (especially ST11) infection and low survival rate, such patients should arouse extensive clinical attention.

Highlights

Klebsiella pneumoniae KP (KP) is a Gram-negative bacillus, which is easy to colonize the upper respiratory tract and intestine of the human body. e detection rate of KP in the pharynx of a healthy population is 1%–6%, and the detection rate of the upper respiratory tract in hospitalized patients is as high as 20%, and the main infection site is the lungs [1, 2]
Many major hospitals have found many cases of infections caused by carbapenem-resistant Klebsiella pneumoniae (CR-KP) and even pan-resistant Klebsiella pneumoniae. ese strains cause serious infections. ere is no cure, the prognosis is poor, and the mortality rate is high
Klebsiella pneumoniae carbapenemase (KPC) enzyme-producing Klebsiella pneumoniae is widespread, and if it is not taken seriously, it will cause outbreaks and epidemics of nosocomial infections, and various hospitals have found pan-resistant strains, carbapenems, and cephalosporins [12, 13]. e KP resistance mechanism and molecular epidemiology investigation of carbapenem-resistant antibacterial drugs are resistant to almost all β-lactams, including penicillins, and once infected, they will face the dilemma of no cure [14]. erefore, microbiologists and clinicians must attach great importance to it

Summary

Introduction

Klebsiella pneumoniae KP (KP) is a Gram-negative bacillus, which is easy to colonize the upper respiratory tract and intestine of the human body. e detection rate of KP in the pharynx of a healthy population is 1%–6%, and the detection rate of the upper respiratory tract in hospitalized patients is as high as 20%, and the main infection site is the lungs [1, 2]. E detection rate of KP in the pharynx of a healthy population is 1%–6%, and the detection rate of the upper respiratory tract in hospitalized patients is as high as 20%, and the main infection site is the lungs [1, 2]. Severe infections are caused when resistance is reduced, and KP is a common conditional pathogen of nosocomial-acquired pneumonia in chronic lung disease patients with diabetes and coma. According to drug resistance monitoring statistics, the detection rate of KP is increasing year by year, and the situation is grim. All areas are severely infected, among which the intensive care unit, respiratory department, urology department, and pediatrics have become the high-risk areas of infection, and the drug resistance is serious [4]. Many major hospitals have found many cases of infections caused by carbapenem-resistant Klebsiella pneumoniae (CR-KP) and even pan-resistant Klebsiella pneumoniae. ese strains cause serious infections. ere is no cure, the prognosis is poor, and the mortality rate is high

Methods

Results

Discussion

Conclusion