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Xia Z, Zhou J, Gao N, Li G, Liu R, Lu G, Shen J. AcrAB-TolC efflux pump overexpression and tet(A) gene mutation increase tigecycline resistance in Klebsiella pneumoniae. World J Microbiol Biotechnol 2024; 40:233. [PMID: 38842631 DOI: 10.1007/s11274-024-04039-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2024] [Accepted: 05/29/2024] [Indexed: 06/07/2024]
Abstract
Tigecycline-non-susceptible Klebsiella pneumoniae (TNSKP) is increasing and has emerged as a global public health issue. However, the mechanism of tigecycline resistance remains unclear. The objective of this study was to investigate the potential role of efflux pump system in tigecycline resistance. 29 tigecycline-non-susceptible Klebsiella pneumoniae (TNSKP) strains were collected and their minimum inhibitory concentrations (MIC) were determined by the broth microdilution method. The ramR, acrR, rpsJ, tet(A), and tet(X) were amplified by polymerase chain reaction (PCR). The mRNA expression of different efflux pump genes and regulator genes were analyzed by real-time PCR. Additionally, KP14 was selected for genome sequencing. KP14 genes without acrB, oqxB, and TetA were modified using suicide plasmids and MIC of tigecycline of KP14 with target genes knocked out was investigated. It was found that MIC of tigecycline of 20 out of the 29 TNSKP strains decreased by over four folds once combined with phenyl-arginine-β-naphthylamide dihydrochloride (PaβN). Most strains exhibited upregulation of AcrAB and oqxAB efflux pumps. The strains with acrB, oqxB, and tetA genes knocked out were constructed, wherein the MIC of tigecycline of KP14∆acrB and KP14∆tetA was observed to be 2 µg/mL (decreased by 16 folds), the MIC of tigecycline of KP14ΔacrBΔTetA was 0.25 µg/mL (decreased by 128 folds), but the MIC of tigecycline of KP14∆oqxB remained unchanged at 32 µg/mL. The majority of TNSKP strains demonstrated increased expression of AcrAB-TolC and oqxAB, while certain strains showed mutations in other genes associated with tigecycline resistance. In KP14, both overexpression of AcrAB-TolC and tet(A) gene mutation contributed to the mechanism of tigecycline resistance.
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Affiliation(s)
- Zhaoxin Xia
- Department of Clinical Laboratory, the First Affiliated Hospital of Anhui Medical University, Hefei, Anhui, China
- Department of Clinical Laboratory, Anhui Public Health Clinical Center, Hefei, Anhui, China
| | - Jing Zhou
- Department of Clinical Laboratory, the First Affiliated Hospital of Anhui Medical University, Hefei, Anhui, China
- Department of Clinical Laboratory, Anhui Public Health Clinical Center, Hefei, Anhui, China
| | - Nana Gao
- Department of Clinical Laboratory, the First Affiliated Hospital of Anhui Medical University, Hefei, Anhui, China
- Department of Clinical Laboratory, Anhui Public Health Clinical Center, Hefei, Anhui, China
| | - Ge Li
- Department of Clinical Laboratory, the First Affiliated Hospital of Anhui Medical University, Hefei, Anhui, China
- Department of Clinical Laboratory, Anhui Public Health Clinical Center, Hefei, Anhui, China
| | - Runde Liu
- Department of Clinical Laboratory, the First Affiliated Hospital of Anhui Medical University, Hefei, Anhui, China
- Department of Clinical Laboratory, Anhui Public Health Clinical Center, Hefei, Anhui, China
| | - Guoping Lu
- Anhui Medical University Affiliated Fuyang Hospital, Fuyang, 236000, Anhui, China
| | - Jilu Shen
- Department of Clinical Laboratory, the First Affiliated Hospital of Anhui Medical University, Hefei, Anhui, China.
- Department of Clinical Laboratory, Anhui Public Health Clinical Center, Hefei, Anhui, China.
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Chen Y, Huang J, Chen H, Xiao H, Shen X, Chen Q, Zhang Z, Huang Y, Wu S, Chen D. Whole genome sequencing analysis of seven unknown resistance mechanisms of carbapenem-resistant Klebsiella pneumoniae strains resistance to ceftazidime-avibactam. J Appl Microbiol 2024; 135:lxae135. [PMID: 38849309 DOI: 10.1093/jambio/lxae135] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2024] [Revised: 05/21/2024] [Accepted: 06/04/2024] [Indexed: 06/09/2024]
Abstract
AIMS To investigate alternative resistance mechanisms among seven ceftazidime-avibactam (CZA)-resistant carbapenem-resistant Klebsiella pneumoniae (CRKP) strains lacking common antimicrobial resistance genes (ARGs) using whole genome sequencing. METHODS AND RESULTS ARG and virulence factors (VFs) were screened using the ARG database CARD and the VF database, respectively, and identified using genomic annotation data with BLAST+. Six strains were ST11 sequence types (STs), and one was ST2123. ST11 strains harbored more ARGs than the ST2123 strains. All seven strains carried multiple ARGs with efflux-mediated antibiotic resistance, including oqxA, oqxB, tet (A), qacEdltal, CRP, H-NS, Kpn-E, F, G, H, acrA, LptD, acrB, acrD, cpxA, mdtB, and mdtC. These efflux-mediated ARGs were identified in most strains and even all strains. Whole genome sequencing revealed that the ST11 strain carried multiple potential prophages, genomic islands, and integrative and conjugative elements, while the ST2123 strain carried an independent potential prophages and a genomic island. CONCLUSIONS Whole genome sequencing analysis revealed that these seven CZA-resistant CRKP strains lacking common ARGs exhibited efflux-mediated antibiotic resistance-associated ARGs. The main mechanism by which CRKP resists CZA is antibiotic inactivation. Except for tet (A), no ARGs and validation experiments related to efflux were found. This study's results provide a new possibility for the resistance mechanism of CRKP to CZA, and we will verify this conclusion through experiments in the future.
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Affiliation(s)
- Yabin Chen
- Clinical Laboratory, Quanzhou First Hospital Affiliated to Fujian Medical University, Quanzhou, Fujian 350525, China
| | - Jianxin Huang
- Shengli Clinical Medical College of Fujian Medical University, Fujian Provincial Hospital, Fuzhou 350001, China
| | - Huidan Chen
- Shengli Clinical Medical College of Fujian Medical University, Fujian Provincial Hospital, Fuzhou 350001, China
| | - Han Xiao
- Medical Technology, First Clinical Medical College, Fujian University of Traditional Chinese Medicine, Fuzhou 350100, China
| | - Xiuqing Shen
- Shengli Clinical Medical College of Fujian Medical University, Fujian Provincial Hospital, Fuzhou 350001, China
| | - Qingqing Chen
- Clinical Laboratory, Quanzhou First Hospital Affiliated to Fujian Medical University, Quanzhou, Fujian 350525, China
| | - Zhishan Zhang
- Clinical Laboratory, Quanzhou First Hospital Affiliated to Fujian Medical University, Quanzhou, Fujian 350525, China
| | - Yi Huang
- Shengli Clinical Medical College of Fujian Medical University, Fujian Provincial Hospital, Fuzhou 350001, China
| | - Shaolian Wu
- Shengli Clinical Medical College of Fujian Medical University, Fujian Provincial Hospital, Fuzhou 350001, China
| | - Dongjie Chen
- Shengli Clinical Medical College of Fujian Medical University, Fujian Provincial Hospital, Fuzhou 350001, China
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Ragheb SM, Osei Sekyere J. Molecular characterization of hypermucoviscous carbapenemase-encoding Klebsiella pneumoniae isolates from an Egyptian hospital. Ann N Y Acad Sci 2024; 1535:109-120. [PMID: 38577761 DOI: 10.1111/nyas.15126] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2023] [Revised: 01/16/2024] [Accepted: 02/21/2024] [Indexed: 04/06/2024]
Abstract
This study aimed to screen antibiotic resistance and virulence genes in carbapenem-resistant hypermucoviscous Klebsiella pneumoniae isolates from an Egyptian hospital. Among 38 previously confirmed carbapenem-nonsusceptible K. pneumoniae isolates, a string test identified three isolates as positive for hypermucoviscosity. Phenotypic characterization and molecular detection of carbapenemase- and virulence-encoding genes were performed. PCR-based multilocus sequence typing and phylogenetics were used to determine the clonality and global epidemiology of the strains. The coexistence of virulence and resistance genes in the isolates was analyzed statistically using a chi-square test. Three isolates showed the presence of carbapenemase-encoding genes (blaNDM, blaVIM, and blaIMP), adhesion genes (fim-H-1 and mrkD), and siderophore genes (entB); the isolates belonged to sequence types (STs) 101, 1310, and 1626. The relatedness between these sequence types and the sequence types of globally detected hypermucoviscous K. pneumoniae that also harbor carbapenemases was determined. Our analysis showed that the resistance and virulence profiles were not homogenous. Phylogenetically, different clones clustered together. There was no significant association between the presence of resistance and virulence genes in the isolates. There is a need for periodic surveillance of the healthcare settings in Egypt and globally to understand the true epidemiology of carbapenem-resistant, hypermucoviscous K. pneumoniae.
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Affiliation(s)
- Suzan Mohammed Ragheb
- Department of Microbiology and Immunology, Faculty of Pharmacy, Modern University for Technology and Information (MTI), Cairo, Egypt
| | - John Osei Sekyere
- Department of Medical Microbiology, School of Medicine, University of Pretoria, Pretoria, South Africa
- Department of Dermatology, School of Medicine, Faculty of Health Sciences, University of Pretoria, Pretoria, South Africa
- Institute of Biomarker Research, Medical Diagnostic Laboratories LLC, Genesis Biotechnology Group, Hamilton, New Jersey, USA
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Park S, Choi J, Shin D, Kwon KT, Kim SH, Wi YM, Ko KS. Conversion to colistin susceptibility by tigecycline exposure in colistin-resistant Klebsiella pneumoniae and its implications to combination therapy. Int J Antimicrob Agents 2024; 63:107017. [PMID: 37884228 DOI: 10.1016/j.ijantimicag.2023.107017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2023] [Revised: 10/13/2023] [Accepted: 10/21/2023] [Indexed: 10/28/2023]
Abstract
OBJECTIVES This study investigated the effect of tigecycline exposure on susceptibility of colistin-resistant Klebsiella pneumoniae isolates to colistin and explored the possibility of antibiotic combination at low concentrations to treat colistin-resistant K. pneumoniae isolates. METHODS Twelve tigecycline-resistant (TIR) mutants were induced in vitro from wild-type, colistin-resistant, and tigecycline-susceptible K. pneumoniae isolates. Antibiotic susceptibility was determined using the broth microdilution method. The deduced amino acid alterations were identified for genes associated with colistin resistance, lipid A biosynthesis, and tigecycline resistance. Expression levels of genes were compared between wild-type stains and TIR mutants using quantitative real-time polymerase chain reaction (PCR). Lipid A modification was explored using MALDI-TOF mass spectrometry. Time-killing assay was performed to assess the efficiency of combination therapy using low concentrations of colistin and tigecycline. RESULTS All TIR mutants except one were converted to be susceptible to colistin. These TIR mutants had mutations in the ramR gene and increased expression levels of ramA. Three genes associated with lipid A biosynthesis, lpxC, lpxL, and lpxO, were also overexpressed in TIR mutants, although no mutation was observed. Additional polysaccharides found in colistin-resistant, wild-type strains were modified in TIR mutants. Colistin-resistant K. pneumoniae strains were eliminated in vitro by combining tigecycline and colistin at 2 mg/L. In this study, we found that tigecycline exposure resulted in reduced resistance of colistin-resistant K. pneumoniae to colistin. Such an effect was mediated by regulation of lipid A modification involving ramA and lpx genes. CONCLUSION Because of such reduced resistance, a combination of colistin and tigecycline in low concentrations could effectively eradicate colistin-resistant K. pneumoniae strains.
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Affiliation(s)
- Suyeon Park
- Department of Microbiology, Sungkyunkwan University School of Medicine, Suwon, Republic of Korea
| | - Jihyun Choi
- Department of Microbiology, Sungkyunkwan University School of Medicine, Suwon, Republic of Korea
| | - Dongwoo Shin
- Department of Microbiology, Sungkyunkwan University School of Medicine, Suwon, Republic of Korea
| | - Ki Tae Kwon
- Department of Internal Medicine, School of Medicine, Kyungpook National University, Daegu, Republic of Korea
| | - Si-Ho Kim
- Division of Infectious Diseases, Department of Medicine, Samsung Changwon Hospital, Sungkyunkwan University School of Medicine, Changwon, Republic of Korea
| | - Yu Mi Wi
- Division of Infectious Diseases, Department of Medicine, Samsung Changwon Hospital, Sungkyunkwan University School of Medicine, Changwon, Republic of Korea
| | - Kwan Soo Ko
- Department of Microbiology, Sungkyunkwan University School of Medicine, Suwon, Republic of Korea.
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Weng Y, Wang T, Huang B, Yu H, Jia W, Shan B, Qu F, Tang Y, Chen L, Du H. Multicenter Study of Colistin Heteroresistance in Carbapenem-Resistant Klebsiella pneumoniae Strains in China. Microbiol Spectr 2023; 11:e0221822. [PMID: 37428093 PMCID: PMC10434274 DOI: 10.1128/spectrum.02218-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2022] [Accepted: 06/23/2023] [Indexed: 07/11/2023] Open
Abstract
Colistin has been considered a last-line option for the treatment of infections caused by carbapenem-resistant Klebsiella pneumoniae (CRKP). Heterogeneous resistance to colistin leads to unexplained clinical colistin treatment failure for CRKP. Our study aimed to investigate the extent of colistin heteroresistance among CRKP strains in China. A total of 455 colistin-susceptible strains, collected from six tertiary care hospitals in China, were characterized. The overall rate of colistin heteroresistance was 6.2%, as determined by the population analysis profiles (PAPs). Genomic analysis revealed that 60.7% of the colistin-heteroresistant isolates belonged to the epidemic sequence type 11 (ST11) clone. Single-nucleotide polymorphisms (SNPs) suggested that 6 ST5216 strains shared the same origin. Each of the subpopulations had a ≥8-fold decrease in colistin MIC in the presence of carbonyl cyanide m-chlorophenylhydrazone (CCCP), which indicated that heteroresistance could be suppressed by an efflux pump inhibitor. In addition, our results suggested that the PhoPQ pathway plays an important role in the mechanisms of heteroresistance. IMPORTANCE The problem of CRKP has raised alarms concerning global health. Our study enriches the epidemiological study of colistin heteroresistance among CRKP strains in China, where the prevalence of this phenomenon was previously unknown. Importantly, colistin-heteroresistant strains may cause the failure of clinical treatment with colistin, even if the clinical laboratory reports that the strains are sensitive. The commonly used broth microdilution method is unable to detect this special phenomenon. Additionally, our results indicate that efflux pumps play a major role in colistin heteroresistance, and inhibitors can effectively reverse it. Our study is the first to provide a detailed analysis of the prevalence of colistin heteroresistance in China, as well as an analysis of the genetic mechanisms of this phenomenon.
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Affiliation(s)
- Yuesong Weng
- Department of Clinical Laboratory, The Second Affiliated Hospital of Soochow University, Suzhou, Jiangsu, China
- Department of Clinical Laboratory, The Affiliated Peoples' Hospital of Ningbo University, Ningbo, Zhejiang, China
- Department of Laboratory Medicine, Ningbo First Hospital, Ningbo, Zhejiang, China
| | - Tao Wang
- Department of Clinical Laboratory, The Second Affiliated Hospital of Soochow University, Suzhou, Jiangsu, China
- Center of Clinical Laboratory, The First Affiliated Hospital of Soochow University, Suzhou, Jiangsu, China
| | - Bin Huang
- Department of Laboratory Medicine, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong, China
| | - Hua Yu
- Sichuan Academy of Medical Science and Sichuan Provincial People’s Hospital, Chengdu, Sichuan, China
| | - Wei Jia
- Center of Medical Laboratory, General Hospital of Ningxia Medical University, Yinchuan, China
| | - Bin Shan
- Department of Laboratory Medicine, The First Affiliated Hospital of Kunming Medical University, Kunming, Yunnan, China
| | - Fen Qu
- Laboratory Medicine Center, Aviation General Hospital, Beijing, China
| | - Yiwei Tang
- Department of Medical Affairs, Danaher Diagnostic Platform/Cepheid (China), New York, New York, USA
| | - Liang Chen
- Hackensack Meridian Health Center for Discovery and Innovation, Nutley, New Jersey, USA
- Department of Medical Sciences, Hackensack Meridian School of Medicine, Nutley, New Jersey, USA
| | - Hong Du
- Department of Clinical Laboratory, The Second Affiliated Hospital of Soochow University, Suzhou, Jiangsu, China
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Huang JM, Sung KC, Lin WC, Lai HY, Wang YJ. Enhancement of capsular hypermucoviscosity in Klebsiella pneumoniae by Acanthamoeba. PLoS Negl Trop Dis 2023; 17:e0011541. [PMID: 37566587 PMCID: PMC10495012 DOI: 10.1371/journal.pntd.0011541] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2023] [Revised: 09/11/2023] [Accepted: 07/18/2023] [Indexed: 08/13/2023] Open
Abstract
BACKGROUND Acanthamoeba and Klebsiella pneumoniae are both environmental commensals. Recently, clinical harm caused by hypermucoviscous K. pneumoniae has been observed. However, the interaction between these microbes and the origin of hypermucoviscous K. pneumoniae have not been reported. METHODOLOGY/PRINCIPAL FINDINGS Here, we report that the bacterial capsule is enlarged when co-cultured with Acanthamoeba using India ink staining, and this effect depends on the number of parasites present. This interaction results in an enhancement of capsular polysaccharide production in the subsequent generations of K. pneumoniae, even without co-culturing with Acanthamoeba. The hypermucoviscosity of the capsule was examined using the sedimentation assay and string test. We also screened other K. pneumoniae serotypes, including K1, K2, K5, and K20, for interaction with Acanthamoeba using India ink staining, and found the same interaction effect. CONCLUSIONS/SIGNIFICANCE These findings suggest that the interaction between Acanthamoeba and K. pneumoniae could lead to harmful consequences in public health and nosocomial disease control, particularly hypermucoviscous K. pneumoniae infections.
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Affiliation(s)
- Jian-Ming Huang
- School of Medicine, National Tsing Hua University, Hsinchu, Taiwan
- Institute of Molecular and Cellular Biology, National Tsing Hua University, Hsinchu, Taiwan
| | - Ko-Chiang Sung
- Department of Clinical Laboratory, Chest Hospital, Ministry of Health and Welfare, Tainan, Taiwan
| | - Wei-Chen Lin
- Department of Microbiology and Immunology, College of Medicine, National Cheng Kung University, Tainan, Taiwan
- Department of Parasitology, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Hong-Yue Lai
- Department of Pharmacology, School of Medicine, China Medical University, Taichung, Taiwan
| | - Yu-Jen Wang
- Department of Parasitology, School of Medicine, China Medical University, Taichung, Taiwan
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Morales-León F, Matus-Köhler M, Araya-Vega P, Aguilera F, Torres I, Vera R, Ibarra C, Venegas S, Bello-Toledo H, González-Rocha G, Opazo-Capurro A. Molecular Characterization of the Convergent Carbapenem-Resistant and Hypervirulent Klebsiella pneumoniae Strain K1-ST23, Collected in Chile during the COVID-19 Pandemic. Microbiol Spectr 2023; 11:e0054023. [PMID: 37191539 PMCID: PMC10269581 DOI: 10.1128/spectrum.00540-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2023] [Accepted: 05/01/2023] [Indexed: 05/17/2023] Open
Abstract
The aim of this study was to investigate the genomic features of a carbapenem-resistant hypervirulent Klebsiella pneumoniae (CR-hvKp) isolate (K-2157) collected in Chile. Antibiotic susceptibility was determined using the disk diffusion and broth microdilution methods. Whole-genome sequencing (WGS) and hybrid assembly were performed, using data generated on the Illumina and Nanopore platforms. The mucoid phenotype was analyzed using both the string test and sedimentation profile. The genomic features of K-2157 (e.g., sequence type, K locus, and mobile genetic elements) were retrieved using different bioinformatic tools. Strain K-2157 exhibited resistance to carbapenems and was identified as a high-risk virulent clone belonging to capsular serotype K1 and sequence type 23 (ST23). Strikingly, K-2157 displayed a resistome composed of β-lactam resistance genes (blaSHV-190, blaTEM-1, blaOXA-9, and blaKPC-2), the fosfomycin resistance gene fosA, and the fluoroquinolones resistance genes oqxA and oqxB. Moreover, several genes involved in siderophore biosynthesis (ybt, iro, and iuc), bacteriocins (clb), and capsule hyperproduction (plasmid-borne rmpA [prmpA] and prmpA2) were found, which is congruent with the positive string test displayed by K-2157. In addition, K-2157 harbored two plasmids: one of 113,644 bp (KPC+) and another of 230,602 bp, containing virulence genes, in addition to an integrative and conjugative element (ICE) embedded on its chromosome, revealing that the presence of these mobile genetic elements mediates the convergence between virulence and antibiotic resistance. Our report is the first genomic characterization of a hypervirulent and highly resistant K. pneumoniae isolate in Chile, which was collected during the coronavirus disease 2019 (COVID-19) pandemic. Due to their global dissemination and public health impact, genomic surveillance of the spread of convergent high-risk K1-ST23 K. pneumoniae clones should be highly prioritized. IMPORTANCE Klebsiella pneumoniae is a resistant pathogen involved primarily in hospital-acquired infections. This pathogen is characterized by its notorious resistance to last-line antibiotics, such as carbapenems. Moreover, hypervirulent K. pneumoniae (hvKp) isolates, first identified in Southeast Asia, have emerged globally and are able to cause infections in healthy people. Alarmingly, isolates displaying a convergence phenotype of carbapenem resistance and hypervirulence have been detected in several countries, representing a serious threat to public health. In this work, we analyzed the genomic characteristics of a carbapenem-resistant hvKp isolate recovered in 2022 from a patient with COVID-19 in Chile, representing the first analysis of this type in the country. Our results will provide a baseline for the study of these isolates in Chile, which will support the adoption of local measures aimed at controlling their dissemination.
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Affiliation(s)
- Felipe Morales-León
- Laboratorio de Investigación en Agentes Antibacterianos, Departamento de Microbiología, Facultad de Ciencias Biológicas, Universidad de Concepción, Concepción, Chile
- Departamento de Farmacia, Facultad de Farmacia, Universidad de Concepción, Concepción, Chile
| | - Maximiliano Matus-Köhler
- Laboratorio de Investigación en Agentes Antibacterianos, Departamento de Microbiología, Facultad de Ciencias Biológicas, Universidad de Concepción, Concepción, Chile
- Departamento de Farmacia, Facultad de Farmacia, Universidad de Concepción, Concepción, Chile
| | - Pablo Araya-Vega
- Laboratorio de Investigación en Agentes Antibacterianos, Departamento de Microbiología, Facultad de Ciencias Biológicas, Universidad de Concepción, Concepción, Chile
| | - Felipe Aguilera
- Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Biológicas, Universidad de Concepción, Concepción, Chile
| | - Ignacio Torres
- Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Biológicas, Universidad de Concepción, Concepción, Chile
| | - Rodrigo Vera
- Hospital de Urgencia Asistencia Pública, Santiago de Chile, Chile
| | - Camila Ibarra
- Hospital de Urgencia Asistencia Pública, Santiago de Chile, Chile
| | | | - Helia Bello-Toledo
- Laboratorio de Investigación en Agentes Antibacterianos, Departamento de Microbiología, Facultad de Ciencias Biológicas, Universidad de Concepción, Concepción, Chile
| | - Gerardo González-Rocha
- Laboratorio de Investigación en Agentes Antibacterianos, Departamento de Microbiología, Facultad de Ciencias Biológicas, Universidad de Concepción, Concepción, Chile
| | - Andrés Opazo-Capurro
- Laboratorio de Investigación en Agentes Antibacterianos, Departamento de Microbiología, Facultad de Ciencias Biológicas, Universidad de Concepción, Concepción, Chile
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8
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Park S, Kim H, Ko KS. Reduced virulence in tigecycline-resistant Klebsiella pneumoniae caused by overexpression of ompR and down-regulation of ompK35. J Biomed Sci 2023; 30:22. [PMID: 37004036 PMCID: PMC10064660 DOI: 10.1186/s12929-023-00910-w] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2022] [Accepted: 02/26/2023] [Indexed: 04/03/2023] Open
Abstract
BACKGROUND The development of tigecycline resistance in hypervirulent Klebsiella pneumoniae strains has resulted in decreased virulence that is associated with reduced production of capsular polysaccharides (CPS). In this study, we investigated the mechanisms that link tigecycline susceptibility to decreased virulence. METHODS We compared transcriptomes from tigecycline-susceptible wild-type strains and tigecycline-resistant mutants using mRNA sequencing. ompR-overexpressed and ompR-deleted mutants were constructed from wild-type strains and tigecycline-resistant mutants, respectively. Antibiotic susceptibility tests were performed, and string tests and precipitation assays were conducted to identify phenotypic changes related to tigecycline susceptibility and ompR expression. Bacterial virulence was assessed by serum resistance and Galleria mellonella infection assays. RESULTS Transcriptomic analyses demonstrated a significant decrease in the expression of ompK35 in the tigecycline-resistant mutants. We observed that tigecycline-resistant mutants overexpressed ompR, and that the expression of ompK35 was regulated negatively by ompR. While tigecycline-resistant mutants and ompR-overexpressed mutants exhibited reduced hypermucoviscosity and virulence, deletion of ompR from tigecycline-resistant mutants restored their hypermucoviscosity and virulence. CONCLUSIONS In hypervirulent K. pneumoniae strains, ompR expression, which is regulated by exposure to tigecycline, may affect the production of CPS, leading to bacterial virulence.
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Affiliation(s)
- Suyeon Park
- Department of Microbiology, Sungkyunkwan University School of Medicine, Suwon, 16419, Republic of Korea
| | - Hyunkeun Kim
- Department of Advanced Bioconvergence Product, Ministry of Food and Drug Safety, Cheongju, 28159, Republic of Korea
| | - Kwan Soo Ko
- Department of Microbiology, Sungkyunkwan University School of Medicine, Suwon, 16419, Republic of Korea.
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9
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Improvement of transformation efficiency in hypermucoviscous Klebsiella pneumoniae using citric acid. J Microbiol Methods 2023; 205:106673. [PMID: 36638870 DOI: 10.1016/j.mimet.2023.106673] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2022] [Revised: 01/06/2023] [Accepted: 01/06/2023] [Indexed: 01/12/2023]
Abstract
Transformation efficiency is very low in hypermucoviscous Kllebsiella pneumoniae owing to high amount of capsular polysaccharide. Here, we propose a method to improve the transformation in hypermucoviscous K. pneumoniae using citric acid. An increased number of recovered transformants was observed in the strains cultured in the presence of citric acid.
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10
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Xu M, Qian C, Jia H, Feng L, Shi S, Zhang Y, Wang L, Cao J, Zhou T, Zhou C. Emergence of Ceftazidime-Avibactam Resistance and Decreased Virulence in Carbapenem-Resistant ST11 Klebsiella pneumoniae During Antibiotics Treatment. Infect Drug Resist 2022; 15:6881-6891. [PMID: 36465808 PMCID: PMC9717589 DOI: 10.2147/idr.s387187] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2022] [Accepted: 11/23/2022] [Indexed: 08/27/2023] Open
Abstract
INTRODUCTION Carbapenem-resistant Klebsiella pneumoniae (CRKP) poses a serious threat to human public health. Ceftazidime-avibactam (CZA) is currently one of the few effective antibiotics for carbapenem-resistant Enterobacteriaceae (CRE). METHODS AND RESULTS Here, we analyzed two longitudinal Klebsiella pneumoniae clinical isolates (FK8578, FK8695) that were isolated from an ICU patient during antimicrobial treatment. Broth microdilution method, whole-genome sequencing (WGS) and comparative genomic analysis were used to elucidate the dynamics and mechanisms of antibiotic resistance. String test, quantification of capsule, biofilm inhibition test and Galleria mellonella (G. mellonella) infection model were used to explore the changes in virulence of the two clinical isolates. During antibiotic treatment, CRKP FK8578 underwent a series of drug resistance and virulence changes, including CZA resistance, carbapenem susceptibility and virulence attenuation. The results of WGS showed that mutation of bla KPC-2 to bla KPC-33 was responsible for the change of drug resistance phenotype between FK8578 and FK8695. pLVPK-like virulence plasmid without siderophore synthesis operon was identified in the two strains. On the other hand, the loss of hypermucoviscosity phenotype in the FK8695 strain may be related to a single nucleotide deletion of the rmpA gene, which would further lead to a decrease in virulence. Virulence results showed that compared with FK8578, FK8695 was negative in the string test, with decreased capsular production, smaller amounts of biofilm formation and higher survival rate of G. mellonella. CONCLUSION This is the first report of CZA resistance and decreased virulence in ST11 CRKP strains during antimicrobial treatment. It is urgent to monitor CZA resistance and timely adjust anti-infective treatment strategies.
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Affiliation(s)
- Mengxin Xu
- Department of Clinical Laboratory, the First Affiliated Hospital of Wenzhou Medical University, Key Laboratory of Clinical Laboratory Diagnosis and Translational Research of Zhejiang Province, Wenzhou, People’s Republic of China
| | - Changrui Qian
- School of Basic Medical Sciences, Wenzhou Medical University, Wenzhou, People’s Republic of China
| | - Huaiyu Jia
- Department of Clinical Laboratory, the First Affiliated Hospital of Wenzhou Medical University, Key Laboratory of Clinical Laboratory Diagnosis and Translational Research of Zhejiang Province, Wenzhou, People’s Republic of China
| | - Luozhu Feng
- Department of Medical Laboratory Science, School of Laboratory Medicine and Life Science, Wenzhou Medical University, Wenzhou, People’s Republic of China
| | - Shiyi Shi
- Department of Clinical Laboratory, the First Affiliated Hospital of Wenzhou Medical University, Key Laboratory of Clinical Laboratory Diagnosis and Translational Research of Zhejiang Province, Wenzhou, People’s Republic of China
| | - Ying Zhang
- Department of Medical Laboratory Science, School of Laboratory Medicine and Life Science, Wenzhou Medical University, Wenzhou, People’s Republic of China
| | - Lingbo Wang
- Department of Clinical Laboratory, the First Affiliated Hospital of Wenzhou Medical University, Key Laboratory of Clinical Laboratory Diagnosis and Translational Research of Zhejiang Province, Wenzhou, People’s Republic of China
| | - Jianming Cao
- Department of Medical Laboratory Science, School of Laboratory Medicine and Life Science, Wenzhou Medical University, Wenzhou, People’s Republic of China
| | - Tieli Zhou
- Department of Clinical Laboratory, the First Affiliated Hospital of Wenzhou Medical University, Key Laboratory of Clinical Laboratory Diagnosis and Translational Research of Zhejiang Province, Wenzhou, People’s Republic of China
| | - Cui Zhou
- Department of Clinical Laboratory, the First Affiliated Hospital of Wenzhou Medical University, Key Laboratory of Clinical Laboratory Diagnosis and Translational Research of Zhejiang Province, Wenzhou, People’s Republic of China
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Gong X, Zhao Q, Wu Y, Zhou H, Ding S, Zhu K. Mucoid Acinetobacter baumannii enhances anti-phagocytosis through reducing C3b deposition. Front Med (Lausanne) 2022; 9:879361. [PMID: 36186828 PMCID: PMC9521736 DOI: 10.3389/fmed.2022.879361] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2022] [Accepted: 08/01/2022] [Indexed: 11/13/2022] Open
Abstract
BackgroundMultidrug resistant (MDR) Acinetobacter baumannii causes serious infections in intensive care units and is hard to be eradicated by antibiotics. Many A. baumannii isolates are identified as the mucoid type recently, but the biological characteristics of mucoid A. baumannii and their interactions with host cells remains unclear.MethodsThe mucoid phenotype, antimicrobial susceptibility, biofilm-forming ability, acid resistance ability, peroxide tolerance, and in vivo toxicity of clinical ICUs derived A. baumannii isolates were first investigated. Secondly, the phagocytic resistance and invasive capacity of A. baumannii isolates to macrophages (MH-S, RAW264.7) and epithelial cells (A549) were analyzed. Furthermore, the abundance of C3b (complement factor C3 degradation product) deposition on the surface of A. baumannii was investigated. Last, the relationship between C3b deposition and the abundance of capsule in A. baumannii isolates were analyzed.ResultsThese A. baumannii strains showed different mucoid phenotypes including hyper mucoid (HM), medium mucoid (MM), and low mucoid (LM). All tested strains were MDR with high tolerance to either acid or hydrogen peroxide exposure. Notably, these mucoid strains showed the increase of mortality in the Galleria mellonella infection models. Besides, the HM strain exhibited less biofilm abundance, higher molecular weight (MW) of capsule, and greater anti-phagocytic activity to macrophages than the LM strain. Together with the increased abundance of capsule, high expression of tuf gene (associated with the hydrolysis of C3b), the HM strain effectively inhibits C3b deposition on bacterial surface, resulting in the low-opsonization phenotype.ConclusionCapsular characteristics facilitate the anti-phagocytic activity in hyper mucoid A. baumannii through the reduction of C3b deposition. Mucoid A. baumannii exhibits high phagocytosis resistance to both macrophages and epithelial cells.
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Affiliation(s)
- Xiaoxia Gong
- National Center for Veterinary Drug Safety Evaluation, College of Veterinary Medicine, China Agricultural University, Beijing, China
| | - Qian Zhao
- National Center for Veterinary Drug Safety Evaluation, College of Veterinary Medicine, China Agricultural University, Beijing, China
- Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou, China
| | - Yifan Wu
- National Center for Veterinary Drug Safety Evaluation, College of Veterinary Medicine, China Agricultural University, Beijing, China
| | - Hongwei Zhou
- Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
| | - Shuangyang Ding
- National Center for Veterinary Drug Safety Evaluation, College of Veterinary Medicine, China Agricultural University, Beijing, China
| | - Kui Zhu
- National Center for Veterinary Drug Safety Evaluation, College of Veterinary Medicine, China Agricultural University, Beijing, China
- Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou, China
- *Correspondence: Kui Zhu,
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Tian D, Liu X, Chen W, Zhou Y, Hu D, Wang W, Wu J, Mu Q, Jiang X. Prevalence of hypervirulent and carbapenem-resistant Klebsiella pneumoniae under divergent evolutionary patterns. Emerg Microbes Infect 2022; 11:1936-1949. [PMID: 35844192 PMCID: PMC9359173 DOI: 10.1080/22221751.2022.2103454] [Citation(s) in RCA: 35] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
K1/K2 hvKP strains acquire carbapenem-resistance plasmids, known as CR-hvKp, and carbapenem-resistant Klebsiella pneumoniae (CRKP) strains obtain virulence plasmids, recognized as hv-CRKP. The two different evolution patterns of hypervirulent combined carbapenem-resistant Klebsiella pneumoniae may lead to their different prevalence in hospitals. Our study aimed to investigate the prevalence of hv-CRKP and CR-hvKp strains and to analyze factors influencing their evolution and prevalence. We collected 890 K. pneumoniae genomes from GenBank and 530 clinical K. pneumoniae isolates from nine hospitals. Our study found that hv-CRKP strains were more prevalent than CR-hvKp strains and both were dominated by blaKPC-2 gene. The blaKPC-2-carrying plasmids could mobilize non-conjugative virulence plasmids from hvKp strains to CRKP strains. The conserved oriT of virulence plasmids and the widespread of conjugative helper plasmids were potential factors for the mobilization of non-conjugative virulence plasmids. HvKp strains with KPC plasmid could hardly simultaneously exhibit hypervirulence and carbapenem resistance as CRKP strains with virulence plasmid, and we found that rfaH mutation reduced capsular synthesis and increased carbapenem resistance of the CR-hvKp strain. In summary, this study revealed that hv-CRKP strains were more suitable for survival in hospital settings than CR-hvKp strains and the widespread conjugative KPC-producing plasmids contributed to the emergence and prevalence of hv-CRKP strains.
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Affiliation(s)
- Dongxing Tian
- Department of Clinical Laboratory, Huashan Hospital, Fudan University, Shanghai, China
| | - Xiao Liu
- School of Pharmacy, Fudan University, Shanghai, China
| | - Wenjie Chen
- Department of Infectious Disease, Huashan Hospital, Fudan University, Shanghai, China
| | - Ying Zhou
- Department of Clinical Laboratory, Huashan Hospital, Fudan University, Shanghai, China.,Department of Clinical Laboratory Medicine, Shanghai Pulmonary Hospital, Tongji University School of Medicine, Shanghai, China
| | - Dakang Hu
- Department of Clinical Laboratory, Huashan Hospital, Fudan University, Shanghai, China
| | - Weiwen Wang
- Department of Clinical Laboratory, Huashan Hospital, Fudan University, Shanghai, China
| | - Jinzuan Wu
- Department of Clinical Laboratory, Pingyang hospital of Wenzhou medical university, Wenzhou, China
| | - Qing Mu
- School of Pharmacy, Fudan University, Shanghai, China.,Department of Clinical Laboratory, Pingyang hospital of Wenzhou medical university, Wenzhou, China
| | - Xiaofei Jiang
- Department of Clinical Laboratory, Huashan Hospital, Fudan University, Shanghai, China
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Hao J, Zhang B, Deng J, Wei Y, Xiao X, Liu J. Emergence of a Hypervirulent Tigecycline-Resistant Klebsiella pneumoniae Strain Co-producing blaNDM–1 and blaKPC–2 With an Uncommon Sequence Type ST464 in Southwestern China. Front Microbiol 2022; 13:868705. [PMID: 35572689 PMCID: PMC9100695 DOI: 10.3389/fmicb.2022.868705] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2022] [Accepted: 03/21/2022] [Indexed: 11/29/2022] Open
Abstract
Emergence of blaNDM–1 and blaKPC–2 co-producing Klebsiella pneumoniae strains is currently attracting widespread attention, but little information is available about their tigecycline resistance, virulence, and prevalence in Southwest China. In July 2021, an extensively drug-resistant K. pneumoniae strain AHSWKP25 whose genome contained both blaNDM–1 and blaKPC–2 genes was isolated from the blood of a patient with the malignant hematological disease in Luzhou, China. We investigated the resistance profiles of AHSWKP25 using microbroth dilution, agar dilution, modified carbapenemase inactivation (mCIM), and EDTA-modified carbapenemase inactivation methods (eCIM). The virulence of AHSWKP25 was assessed through string tests, serum killing assays, and a Galleria mellonella larval infection model. Conjugation and plasmid stability experiments were conducted to determine the horizontal transfer capacity of plasmids. And efflux pump phenotype test and real-time quantitative reverse transcription-PCR (RT-PCR) were used to determine its efflux pump activity. Sequencing of AHSWKP25 determined that AHSWKP25 belonged to ST464, which is resistant to antibiotics such as carbapenems, tetracycline, fluoroquinolones, tigecycline, and fosfomycin. The efflux pump phenotype tests and RT-PCR results demonstrated that efflux pumps were overexpressed in the AHSWKP25, which promoted the tigecycline resistance of the bacteria. AHSWKP25 also showed hypervirulence and serum resistance in vitro model. AHSWKP25 carried several different plasmids that contained blaNDM–1, blaKPC–2, and mutated tet(A) genes. Sequence alignment revealed that the plasmids carrying blaNDM–1 and blaKPC–2 underwent recombination and insertion events, respectively. We demonstrated that an X3 plasmid carrying blaNDM–1 was transferred from pSW25NDM1 to E. coli J53. We also identified missense mutations in the ramR, rcsA, lon, and csrD genes of AHSWKP25. Our results highlighted the potential of blaNDM–1 and blaKPC–2 co-producing K. pneumoniae strains to further develop antimicrobial resistance and hypervirulent phenotypes, but measures should be taken to closely monitor and control the spread of superbugs with multidrug-resistant phenotypes and hypervirulence.
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Affiliation(s)
- Jingchen Hao
- Department of Laboratory Medicine, The Affiliated Hospital of Southwest Medical University, Luzhou, China
| | - Bangqin Zhang
- Department of Laboratory Medicine, The Affiliated Hospital of Southwest Medical University, Luzhou, China
| | - Jiamin Deng
- Department of Respiratory and Critical Care Medicine, The Affiliated Hospital of Southwest Medical University, Luzhou, China
| | - Yueshuai Wei
- Department of Laboratory Medicine, The Affiliated Hospital of Southwest Medical University, Luzhou, China
| | - Xue Xiao
- Department of Laboratory Medicine, Southwest Medical University, Luzhou, China
| | - Jinbo Liu
- Department of Laboratory Medicine, The Affiliated Hospital of Southwest Medical University, Luzhou, China
- *Correspondence: Jinbo Liu,
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Di Pilato V, Henrici De Angelis L, Aiezza N, Baccani I, Niccolai C, Parisio EM, Giordano C, Camarlinghi G, Barnini S, Forni S, Righi L, Mechi MT, Giani T, Antonelli A, Rossolini GM. Resistome and virulome accretion in an NDM-1-producing ST147 sublineage of Klebsiella pneumoniae associated with an outbreak in Tuscany, Italy: a genotypic and phenotypic characterisation. THE LANCET MICROBE 2022; 3:e224-e234. [DOI: 10.1016/s2666-5247(21)00268-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2020] [Revised: 08/26/2021] [Accepted: 09/23/2021] [Indexed: 10/24/2022] Open
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Two Distinct Genotypes of KPC-2-Producing Klebsiella pneumoniae Isolates from South Korea. Antibiotics (Basel) 2021; 10:antibiotics10080911. [PMID: 34438961 PMCID: PMC8388746 DOI: 10.3390/antibiotics10080911] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Revised: 07/24/2021] [Accepted: 07/24/2021] [Indexed: 11/17/2022] Open
Abstract
In this study, we investigated the characteristics of KPC-2-producing Klebsiella pneumoniae (KP-Kp) isolates from a hospital in South Korea. Among the 37 KP-Kp isolates, two main clones were identified-ST11 and ST307. ST11 isolates showed higher minimum inhibitory concentrations for carbapenems than ST307 isolates. All ST307 isolates were resistant to gentamicin and trimethoprim-sulfamethoxazole, but ST11 isolates were not. However, most tigecycline-resistant or colistin-resistant isolates belonged to ST11. The two KP-Kp clones showed different combinations of wzi and K serotypes. Plasmids from ST11 KP-Kp isolates exhibited diverse incompatibility types. Serum resistance and macrophage infection assays indicated that ST11 may be more virulent than ST307. The changes in the main clones of KP-Kp isolates over time as well as the different characteristics of these clones, including virulence, suggest the need for their continuous monitoring.
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Yan WJ, Jing N, Wang SM, Xu JH, Yuan YH, Zhang Q, Li AL, Chen LH, Zhang JF, Ma B, Ma Q, Li Y. Molecular characterization of carbapenem-resistant Enterobacteriaceae and emergence of tigecycline non-susceptible strains in the Henan province in China: a multicentrer study. J Med Microbiol 2021; 70. [PMID: 33587030 PMCID: PMC8346725 DOI: 10.1099/jmm.0.001325] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
Introduction Carbapenem-resistant Enterobacteriaceae (CRE) have been responsible for nosocomial outbreaks worldwide and have become endemic in several countries. Hypothesis/Gap Statement To better understand the epidemiological trends and characteristics of CRE in the Henan province. Aim We assessed the molecular epidemiological characteristics of 305 CRE strains isolated from patients in 19 secondary or tertiary hospitals in ten areas of the Henan province in China. Methodology A total of 305 CRE isolates were subjected to multiple tests, including in vitro antimicrobial susceptibility testing, PCR for carbapenemase genes blaKPC, blaNDM, blaIMP, blaVIM, blaOXA-48-like. Tigecycline-resistant genes ramR, oqxR, acrR, tetA, rpsJ, tetX, tetM, tetL were analysed in five tigecycline non-susceptible carbapenem-resistant Klebsiella pneumoniae isolates (TNSCRKP). Additionally, multilocus sequence typing (MLST) was performed for carbapenem-resistant K. pneumoniae (CRKP). Results The most common CRE species were K. pneumoniae (234, 77 %), Escherichia coli (36, 12 %) and Enterobacter cloacae (13, 4 %). All strains exhibited multi-drug resistance. Overall, 97 % (295/305) and 97 % (297/305) of the isolates were susceptible to polymyxin B and tigecycline, respectively. A total of 89 % (271/305) of the CRE isolates were carbapenemase gene-positive, including 70 % blaKPC, 13 % blaNDM, 6 % blaIMP, and 1 % combined blaKPC/blaNDM genes. K. pneumoniae carbapenemase (KPC) was the predominant carbapenemase in K. pneumoniae (87 %), whereas NDM and IMP were frequent in E. coli (53 %) and E. cloacae (69 %), respectively. Mutations in the ramR, tetA, and rpsJ genes were detected in five TNSCRKP. Moreover, 15 unique sequence types were detected, with ST11 (74 %), ST15 (9 %) and ST2237 (5 %) being dominant among K. pneumoniae strains. Conclusion A high proportion of CRE strains were carbapenemase-positive, and five carbapenem-resistant K. pneumonia isolates were tigecycline non-susceptible, indicating a need for the ongoing surveillance of CRE and effective measures for the prevention of CRE infections.
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Affiliation(s)
- Wen Juan Yan
- Department of Clinical Microbiology, Henan Provincial People's Hospital, People's Hospital of Zhengzhou University, People's Hospital of Henan University, Zhengzhou, Henan, 450003, PR China
| | - Nan Jing
- Department of Clinical Microbiology, Henan Provincial People's Hospital, People's Hospital of Zhengzhou University, People's Hospital of Henan University, Zhengzhou, Henan, 450003, PR China
| | - Shan Mei Wang
- Department of Clinical Microbiology, Henan Provincial People's Hospital, People's Hospital of Zhengzhou University, People's Hospital of Henan University, Zhengzhou, Henan, 450003, PR China
| | - Jun Hong Xu
- Department of Clinical Microbiology, Henan Provincial People's Hospital, People's Hospital of Zhengzhou University, People's Hospital of Henan University, Zhengzhou, Henan, 450003, PR China
| | - You Hua Yuan
- Department of Clinical Microbiology, Henan Provincial People's Hospital, People's Hospital of Zhengzhou University, People's Hospital of Henan University, Zhengzhou, Henan, 450003, PR China
| | - Qi Zhang
- Department of Clinical Microbiology, Henan Provincial People's Hospital, People's Hospital of Zhengzhou University, People's Hospital of Henan University, Zhengzhou, Henan, 450003, PR China
| | - A Li Li
- Department of Clinical Laboratory, Xiayi Traditional Chinese Medicine Hospital, Shangqiu, Henan, 4764007, PR China
| | - Li Hao Chen
- Department of Clinical Laboratory, Zhoukou Traditional Chinese Medicine Hospital, Zhoukou, Henan, 466000, PR China
| | - Jiang Feng Zhang
- Department of Clinical Microbiology, Henan Provincial People's Hospital, People's Hospital of Zhengzhou University, People's Hospital of Henan University, Zhengzhou, Henan, 450003, PR China
| | - Bing Ma
- Department of Clinical Microbiology, Henan Provincial People's Hospital, People's Hospital of Zhengzhou University, People's Hospital of Henan University, Zhengzhou, Henan, 450003, PR China
| | - Qiong Ma
- Department of Clinical Microbiology, Henan Provincial People's Hospital, People's Hospital of Zhengzhou University, People's Hospital of Henan University, Zhengzhou, Henan, 450003, PR China
| | - Yi Li
- Department of Clinical Microbiology, Henan Provincial People's Hospital, People's Hospital of Zhengzhou University, People's Hospital of Henan University, Zhengzhou, Henan, 450003, PR China
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