Molecular Epidemiology of Hypervirulent Carbapenemase-Producing Klebsiella pneumoniae

ObjectiveTo investigate the overall distributions of key virulence genes in Klebsiella pneumoniae, especially the hypervirulent blaKPC-positive K. pneumoniae (Hv-blaKPC(+)-KP).MethodsA total of 521 complete genomes of K. pneumoniae from GenBank were collected and analyzed. Multilocus sequence typing, molecular serotyping, antibiotic-resistance, virulence genes and plasmid replicon typing were investigated.ResultsPositive rates of virulence genes highly varied, ranging from 2.9 (c-rmpA/A2) to 99.6% (entB). Totally 207 strains presented positive fimH, mrkD, entB and wzi and 190 showed positive fimH, mrkD, entB, irp2 and wzi, which were the two primary modes. A total of 94, 165 and 29 strains were denoted as hypervirulent K. pneumoniae (HvKP), blaKPC(+)-KP and Hv-blaKPC(+)-KP. ST11 accounted for 17 among the 29 Hv-blaKPC(+)-KP strains; Genes iucA, p-rmpA2 and p-rmpA were positive in 28, 26 and 18 Hv-blaKPC(+)-KP strains respectively. Among the 29 Hv-blaKPC(+)-KP strains exhibiting four super clusters from GenBank, IncHI1B plasmids carrying virulence genes and IncFII ones with blaKPC were responsible for both 23 strains respectively.ConclusionsPositive rates of virulence genes vary remarkably in K. pneumoniae. Genes iucA, p-rmpA2 and p-rmpA were primary ones inducing Hv-blaKPC(+)-KP. IncHI1B plasmids carrying virulence genes and IncFII ones with blaKPC constitute the primary combination responsible for Hv-blaKPC(+)-KP. The making of Hv-blaKPC(+)-KP is mostly via blaKPC(+)-KP acquiring another plasmid harboring virulence genes.

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Distribution of virulence genes and the molecular epidemiology of Streptococcus pyogenes clinical isolates by emm and multilocus sequence typing methods

10.21203/rs.3.rs-44181/v1 ◽

2020 ◽

Author(s):

Siti Nur Adila Hamzah ◽

Mohd Nasir Mohd Desa ◽

Azmiza Syawani Jasni ◽

Niazlin Mohd Taib ◽

Siti Norbaya Masri ◽

...

Keyword(s):

Molecular Epidemiology ◽

Virulence Factors ◽

Streptococcus Pyogenes ◽

Multilocus Sequence Typing ◽

Virulence Genes ◽

Clinical Samples ◽

Pcr Analysis ◽

Gold Standard Method ◽

Non Invasive ◽

Typing Methods

Abstract Background: Streptococcus pyogenes has a variety of virulence factors and the predominant invasive strains differ according to specific emm types and geographical orientation. Although emm typing is commonly used as the gold standard method for the molecular characterization, multilocus sequence typing (MLST) has become an important tool for comparing the genetic profiles globally. This study aimed to screen selected virulence genes from invasive and non-invasive clinical samples and to characterize the molecular epidemiology by emm typing and MLST methods. Methods: A total of 42 S. pyogenes isolates from invasive and non-invasive samples collected from 2014 to 2015 from two different tertiary hospitals were investigated for the distribution of virulence factors and their molecular epidemiology by emm and multilocus sequence typing methods. Detection of five virulence genes (speA , speB , speJ , ssa and sdaB) was performed using multiplex polymerase chain reaction (PCR) using the standard primers and established protocol. Results: Multiplex PCR analysis revealed that sdaB/speF (78.6%) and speB (61.9%) were the predominant virulence genes. Regardless of the type of invasiveness, diverse distribution of emm types/subtypes was noted which comprised of 27 different emm types/subtypes. The predominant emm types/subtypes were emm63 and emm18 with each gene accounted for 11.8% whereas 12% for each gene was noted for emm28, emm97.4 and emm91. The MLST revealed that the main sequence type (ST) in invasive samples was ST402 (17.7%) while ST473 and ST318 (12% for each ST) were the major types in non-invasive samples. Out of 18 virulotypes, Virulotype A (five genes, 55.6%) and Virulotype B (two genes, 27.8%) were the major virulotypes found in this study. Phylogenetic analysis indicated the presence of seven different clusters of S. pyogenes. Interestingly, Cluster VI showed that selected emm/ST types such as emm71/ST318 (n=2), emm70.1/ST318 (n=1), emm44/ST31 (n=1) and emm18/ST442 (n=1) have clustered within a common group (Virulotype A) for both hospitals studied. Conclusion: The present study showed that group A streptococci (GAS) are genetically diverse and possess virulence genes regardless of their invasiveness. Majority of the GAS exhibited no restricted pattern of virulotypes except for a few distinct clusters. Therefore, it can be concluded that virulotyping is partially useful for characterizing a heterogeneous population of GAS in hospitals.

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Erratum to: Characterization of Klebsiella pneumoniae complex isolates from pigs and humans in farms in Thailand: population genomic structure, antibiotic resistance and virulence genes

Journal of Antimicrobial Chemotherapy ◽

10.1093/jac/dkab156 ◽

2021 ◽

Author(s):

Thongpan Leangapichart ◽

Kamonwan Lunha ◽

Jatesada Jiwakanon ◽

Sunpetch Angkititrakul ◽

Josef D Järhult ◽

...

Keyword(s):

Antibiotic Resistance ◽

Klebsiella Pneumoniae ◽

Virulence Genes ◽

Genomic Structure ◽

Population Genomic

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Virulence Factors, Antibiotic Resistance patterns, and Molecular Types of Clinical Isolates of Klebsiella Pneumoniae

10.21203/rs.3.rs-331542/v1 ◽

2021 ◽

Author(s):

Mitra Ahmadi ◽

Payam Behzadi ◽

Reza Ranjbar

Keyword(s):

Antibiotic Resistance ◽

Klebsiella Pneumoniae ◽

Molecular Typing ◽

Virulence Genes ◽

Multidrug Resistant ◽

Resistance Mechanisms ◽

Aminoglycoside Resistance ◽

Wide Range ◽

Resistance Patterns ◽

Esbl Producers

Abstract Background Klebsiella pneumoniae is armed with a wide range of antibiotic resistance mechanisms which mostly challenges effective treatment. Due to this fact, the aims of the current study were to identify the clinical strains of K . pneumoniae as well as to determine their phenotypes and molecular characterization related to antimicrobial resistance and virulence genes. Methods In this investigation, specimens from a hospital and different laboratories located in Shahr-e-Qods, Tehran, Iran were collected during a period of nine-month (December 2018 to August 2019). The isolated strains of K. pneumoniae were then identified through standard microbial and biochemical assays. Additionally, disk diffusion, combined disk, modified Hodge test and PCR were performed for antibiotic resistance of the strains and virulence genes profiling, respectively. The molecular typing was accomplished by ERIC-PCR. Results Eighty-four isolates of K. pneumoniae were identified and subjected to the study. Fifty- two percent of the isolated strains of K. pneumoniae were detected as multidrug resistant (MDR) pathotypes with the highest resistance to ceftriaxone (65%) and the lowest resistance to colistin (23%). Twenty-seven (52%) out of 52 (100%) MDR pathotypes of isolated K. pneumoniae were identified as ESBL producers. According to Modified Hodge Test (MHT) results, out of 24 resistant strains of isolated K. pneumoniae to imipenem and meropenem, 15 pathotypes (62.5%) were detected as KPC producers. The gene of blaCTX (encoding carbapenemase) with 96% ranked first, while the blaKPC gene with the prevalence of 71% ranked second among ESBL producers. The aminoglycoside resistance gene of Aac6-Ib showed the highest frequency with the prevalence percentage of 90%. The virulence genes of mrkD (94%) and magA (11%) were the highest and lowest among isolates, respectively. According to ERIC-PCR results the isolated strains of K. pneumoniae were divided into four clusters in which the cluster 4 was predominant group. Conclusions The high prevalence of antibiotic resistance and virulence genes in conjunction with a significant relationship between the strains reveals a high pathogenic capacity of the isolated pathotypes of K. pneumoniae . These findings emphasize the choose of more effective antibiotic regimens for treatment of infections caused by K. pneumoniae. Keywords: Klebsiella pneumoniae , antibiotic resistance, ESBL, virulence genes, molecular typing.

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Frequency of blaCTX-M and blaTEM Virulence Genes and Antibiotic Resistance Profiles among Klebsiella pneumoniae Isolates in Urinary Tract Infection (UTI) Samples from Hashtgerd, Iran

Reports of Biochemistry and Molecular Biology ◽

10.52547/rbmb.10.3.412 ◽

2021 ◽

Vol 10 (3) ◽

pp. 412-419

Author(s):

Shirin Sarshar ◽

Reza Mirnejad ◽

Ebrahim Babapour ◽

◽

...

Keyword(s):

Urinary Tract Infection ◽

Antibiotic Resistance ◽

Urinary Tract ◽

Tract Infection ◽

Klebsiella Pneumoniae ◽

Virulence Genes

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Risk Factors and Outcomes for Carbapenem-Resistant Klebsiella pneumoniae Isolation, Stratified by Its Multilocus Sequence Typing: ST258 Versus Non-ST258

Open Forum Infectious Diseases ◽

10.1093/ofid/ofv213 ◽

2016 ◽

Vol 3 (1) ◽

Cited By ~ 9

Author(s):

Sorabh Dhar ◽

Emily T. Martin ◽

Paul R. Lephart ◽

John P. McRoberts ◽

Teena Chopra ◽

...

Keyword(s):

Risk Factors ◽

High Risk ◽

Klebsiella Pneumoniae ◽

Molecular Epidemiology ◽

Clinical Outcomes ◽

Multilocus Sequence Typing ◽

Clinical Impact ◽

Sequence Type ◽

Epidemiological Investigation ◽

Carbapenem Resistant

Abstract A “high risk” clone of carbapenem-resistant Klebsiella pneumoniae (CRKP) identified by multilocus sequence typing (MLST) as sequence type (ST) 258 has disseminated worldwide. As the molecular epidemiology of the CRE pandemic continues to evolve, the clinical impact of non-ST258 strains is less well defined. We conducted an epidemiological investigation of CRKP based on strains MLST. Among 68 CRKP patients, 61 were ST258 and 7 belonged to non-ST258. Klebsiella pneumoniae ST258 strains were significantly associated with blaKPC production and with resistance to an increased number of antimicrobials. Clinical outcomes were not different. Based on this analysis, one cannot rely solely on the presence of blaKPC in order to diagnose CRKP.

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Virulence characterization of Klebsiella pneumoniae and its relation with ESBL and AmpC beta-lactamase associated resistance

Iranian Journal of Microbiology ◽

10.18502/ijm.v12i2.2613 ◽

2020 ◽

Author(s):

Elghar Soltani ◽

Alka Hasani ◽

Mohammad Ahangarzadeh Rezaee ◽

Tahereh Pirzadeh ◽

Mahin Ahangar Oskouee ◽

...

Keyword(s):

Antibiotic Resistance ◽

Klebsiella Pneumoniae ◽

Virulence Genes ◽

Diffusion Method ◽

Beta Lactamase ◽

Disk Diffusion Method ◽

Extended Spectrum Beta Lactamase ◽

Virulence Trait ◽

Polymerase Chain

Background and Objectives: Trend analysis reveals that Klebsiella pneumoniae has witnessed a steep enhancement in the antibiotic resistance and virulence over the last few decades. The present investigation aimed at a comprehensive approach investigating antibiotic susceptibility including, extended spectrum beta-lactamase (ESBL) and AmpC β-lactamase (AmpC) resistance and the prevalence of virulence genes among the K. pneumoniae isolates. Materials and Methods: Sixty-one K. pneumoniae isolates were obtained from various clinical infections. Antimicrobial susceptibility was performed by disk diffusion method. The Mast® D68C test detected the presence of ESBLs and AmpCs phenotypically, and later presence of ESBL and AmpC genes was observed by polymerase chain reaction (PCR). Multi- plex-PCR was performed to investigate various virulence genes. CMY-2 Results: Amongst 61 K. pneumoniae isolates, 59% were observed as ESBL and 14.7% as AmpC producers. All ESBL CTX-M-15 producers were positive for bla CTX-M-15 , while bla CTX-M-14 was observed in 54.1% isolates. The frequency of AmpC genes was CMY-2 as follows: bla CMY-2 (60.7%) and bla DHA-1 (34.4%). The most frequent virulence genes were those encoding enterobactin and DHA-1 lipopolysaccharide. Presence of mrkD was associated with bla CMY-2 DHA-1 gene, while bla significantly (p≤0.05) correlated DHA-1 with the presence of iutA and rmpA virulence genes. bla positive isolates had urine as a significant source, while bla positive isolates were mainly collected from wound exudates (p≤0.05). Conclusion: Our results highlight that ESBL and AmpC production along with a plethora of virulence trait on K. pneumoni- ae should be adequately considered to assess its pathogenesis and antibiotic resistance.

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Genetic Features of the Widespread Plasmid Coding for the Carbapenemase OXA-48

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.05289-11 ◽

2011 ◽

Vol 56 (1) ◽

pp. 559-562 ◽

Cited By ~ 225

Author(s):

Laurent Poirel ◽

Rémy A. Bonnin ◽

Patrice Nordmann

Keyword(s):

Antibiotic Resistance ◽

Klebsiella Pneumoniae ◽

Molecular Epidemiology ◽

Resistance Gene ◽

Antibiotic Resistance Gene ◽

Content Type ◽

Genetic Features ◽

Complete Sequencing

ABSTRACTComplete sequencing of plasmid pOXA-48a carrying theblaOXA-48gene from aKlebsiella pneumoniaeisolate was performed. Its backbone corresponded to that of an IncL/M-type plasmid, in which theblaOXA-48gene had been integrated through the acquisition of the Tn1999composite transposon without any other antibiotic resistance gene. Molecular epidemiology using a collection of international OXA-48 producers revealed the wide diffusion of pOXA-48a or closely related plasmids.

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Virulence Factors and Molecular Epidemiology of Pyogenic Liver Abscess Causing Multidrug Resistant Klebsiella pneumoniae in Wenzhou, China

10.21203/rs.3.rs-42660/v1 ◽

2020 ◽

Author(s):

Zhongyong Wang ◽

Siqin Zhang ◽

Na Huang ◽

Shixing Liu ◽

Ye Xu ◽

...

Keyword(s):

Klebsiella Pneumoniae ◽

Molecular Epidemiology ◽

Liver Abscess ◽

Virulence Factors ◽

Virulence Genes ◽

Pyogenic Liver Abscess ◽

Multidrug Resistant ◽

Carbapenem Resistant ◽

Tertiary Teaching ◽

Tertiary Teaching Hospital

Abstract Background: To date, little is known about virulence characteristics of pyogenic liver abscess (PLA) causing multidrug resistant (MDR) Klebsiella pneumoniae (K. pneumoniae). It may be these strains are rare. The aim of this study was to analyze the virulence and molecular epidemiology of 12 MDR strains from 163 PLA cases in a tertiary teaching hospital from the perspective of clinical characteristics, virulence phenotypes and genotypes.Results: The virulence phenotypes of the twelve PLA-causing MDR K. pneumoniae were similar or even more obvious than those of sensitive hypervirulent Klebsiella pneumoniae control strains. These MDR strains were mainly non-K1/K2 serotypes and carried multiple virulence genes. Multilocus sequence typing (MLST) revealed the PLA-causing MDR strains had low clone correlation.Conclusions: This study was the first analysis on virulence factors of PLA-causing MDR strains. The virulent factors exhibited the coexistence of hypervirulence and multidrug resistance in PLA-causing MDR K. pneumoniae strains, and these MDR strains were mainly polyclonal spread and there was firstly found one ST11 carbapenem-resistant hypervirulent strain in PLA.

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Genotyping and Virulence Analysis of Drug Resistant Clinical Klebsiella pneumoniae Isolates in Egypt

Journal of Pure and Applied Microbiology ◽

10.22207/jpam.14.3.36 ◽

2020 ◽

Vol 14 (3) ◽

pp. 1967-1975

Author(s):

Sarah M. Abdelhamid ◽

Hala Mohamed Abd-Elaal ◽

Moustafa Osama Matareed ◽

Kholoud Baraka

Keyword(s):

Antibiotic Resistance ◽

Klebsiella Pneumoniae ◽

Molecular Typing ◽

Virulence Genes ◽

Antimicrobial Agents ◽

Antibiotic Resistance Genes ◽

Epidemiological Studies ◽

Diffusion Method ◽

Drug Resistant ◽

Horizontal Spread

Klebsiella pneumoniae is a highly drug-resistant human pathogen responsible for a variety of serious infections. Integrons, mobile genetic elements capable of integrating antibiotic resistance genes, and the capsule are important virulence factors that increase bacteria resistance to phagocytosis and antimicrobial agents. Molecular typing is an effective tool for identifying the likely etiology of infection. This study aimed to investigate the presence of the rmpA, wcaG, intI1, intI2, and intI3 virulence genes in clinical Klebsiella pneumoniae isolates, and explore their molecular genotypes by using ERIC-PCR. Fifty Klebsiella pneumoniae strains were isolated from various specimens. Antimicrobial resistance was evaluated by using the disc diffusion method. Five genes were amplified by conventional PCR. Genotyping was performed molecularly by using ERIC-PCR. Forty-seven isolates were multi-drug resistant. In all, 18%, 36%, and 98% of the 50 K. pneumoniae isolates were positive for rmpA, wcaG, and intI1 genes, respectively; however, all isolates were negative for intI2 and intI3 genes. Dendogram analysis of the ERIC-PCR results showed 49 distinct patterns, arranged in five clusters. Our study demonstrates high levels of antibiotic resistance and virulence among clinical isolates of K. pneumoniae. Such resistance reflects a growing problem for public health. Further, the presence of integrons increases the horizontal spread of antibiotic resistance and virulence genes among bacterial isolates. The ERIC-PCR technique is an effective method for molecular typing and epidemiological studies of hospital-acquired infections.

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