scholarly journals Genomic characterization of carbapenem resistant Escherichia coli from multiple hospitals in Nanjing, China: focusing on frequent co-occurrence of blaNDM and blaKPC-2

2020 ◽  
Author(s):  
Xiaoli Cao ◽  
Jie Zheng ◽  
Li Cheng ◽  
Wanqing Zhou ◽  
Zhifeng Zhang ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Control Measures ◽  
Potential Threat ◽  
E Coli ◽  
Infection Control Measures ◽  
Carbapenem Resistant ◽  
Plasmid Replicon ◽  
Drum Tower Hospital ◽  
Genomic Characterization

Abstract Background The increasing emergence of carbapenem resistant Escherichia coli (CREC) poses a potential threat to public health, hence genomic characterization of isolates is needed for a better understanding of its transmission and implementation of infection control measures. Materials and methods Eleven CREC isolates were collected in 2015 from 6 hospitals in Nanjing, China, and analyzed using whole genome sequencing. Resistance determinants, virulence elements, multi-locus sequence type (MLST), serotypes, phylogeny and fimH types were determined. Results All of the CREC carried at least one carbapenemase. NDM-5 (n = 9) was the most frequent carbapenemase, followed by KPC-2 (n = 3) and NDM-1 (n = 2); three isolates produced NDM-5 and KPC-2. Ten out of the 11 isolates co-carried blaCTX-M variants. MLST analysis found 7 distinct STs, including ST410 (n = 2), ST3489 (n = 1), ST156 (n = 1), ST683 (n = 1), ST297 (n = 1), ST167 (n = 1), and ST361 (n = 1). Six distinct serotypes and 8 Fim types were identified. A great diversity of plasmid profiles was observed with plasmid replicon IncX3 being the most frequent (n = 11). Phylogenetic analysis showed great diversity between the 11 CREC isolates and also between 6 additional isolates co-carrying blaNDM and blaKPC which were selected from the strains collection of Nanjing Drum Tower Hospital for comparison. Conjugation assays demonstrated that blaNDM was transferable. Conclusion NDM is the major carbapenemase among CREC, with NDM-5 being the main variant which can be horizontally disseminated by IncX3 plasmids. These isolates displayed genetic diversity by MLST, Fim typing and serotyping. We herein provided the first report on emergence of NDM-5 producing E. coli ST297, ST683, ST3489, and NDM-1 producing E. coli ST361.

scholarly journals Genomic characterization of carbapenem resistant Escherichia coli from multiple hospitals in Nanjing, China: focusing on frequent co-occurrence of blaNDM and blaKPC-2 

2020 ◽  
Author(s):  
Xiaoli Cao ◽  
Jie Zheng ◽  
Li Cheng ◽  
Wanqing Zhou ◽  
Zhifeng Zhang ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Control Measures ◽  
Potential Threat ◽  
E Coli ◽  
Infection Control Measures ◽  
Carbapenem Resistant ◽  
Plasmid Replicon ◽  
Drum Tower Hospital ◽  
Genomic Characterization

Abstract Background: The increasing emergence of carbapenem resistant Escherichia coli (CREC) poses a potential threat to public health, hence genomic characterization of isolates is needed for a better understanding of its transmission and implementation of infection control measures. Materials and methods：Eleven CREC isolates were collected in 2015 from 6 hospitals in Nanjing, China, and analyzed using whole genome sequencing. Resistance determinants, virulence elements, multi-locus sequence type (MLST), serotypes, phylogeny and fimH types were determined. Results: All of the CREC carried at least one carbapenemase. NDM-5 (n=9) was the most frequent carbapenemase, followed by KPC-2 (n=3) and NDM-1 (n=2); three isolates produced NDM-5 and KPC-2. Ten out of the 11 isolates co-carried blaCTX-M variants. MLST analysis found 7 distinct STs, including ST410 (n=2), ST3489 (n=1), ST156 (n=1), ST683 (n=1), ST297 (n=1), ST167 (n=1), and ST361 (n=1). Six distinct serotypes and 8 Fim types were identified. A great diversity of plasmid profiles was observed with plasmid replicon IncX3 being the most frequent (n=11). Phylogenetic analysis showed great diversity between the 11 CREC isolates and also between 6 additional isolates co-carrying blaNDM and blaKPC which were selected from the strains collection of Nanjing Drum Tower Hospital for comparison. Conjugation assays demonstrated that blaNDM was transferable. Conclusion: NDM is the major carbapenemase among CREC, with NDM-5 being the main variant which can be horizontally disseminated by IncX3 plasmids. These isolates displayed genetic diversity by MLST, Fim typing and serotyping. We herein provided the first report on emergence of NDM-5 producing E. coli ST297, ST683, ST3489, and NDM-1 producing E. coli ST361.

scholarly journals Molecular Characterization of Commensal Escherichia coli Adapted to Different Compartments of the Porcine Gastrointestinal Tract

2012 ◽  
Vol 78 (19) ◽  
pp. 6799-6803 ◽  
Author(s):  
Sam Abraham ◽  
David M. Gordon ◽  
James Chin ◽  
Huub J. M. Brouwers ◽  
Peter Njuguna ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Gastrointestinal Tract ◽  
Random Amplified Polymorphic Dna ◽  
Content Type ◽  
E Coli ◽  
Plasmid Replicon ◽  
Different Strains ◽  
Different Characteristics

ABSTRACTThe role ofEscherichia colias a pathogen has been the focus of considerable study, while much less is known about it as a commensal and how it adapts to and colonizes different environmental niches within the mammalian gut. In this study, we characterizeEscherichia coliorganisms (n= 146) isolated from different regions of the intestinal tracts of eight pigs (dueodenum, ileum, colon, and feces). The isolates were typed using the method of random amplified polymorphic DNA (RAPD) and screened for the presence of bacteriocin genes and plasmid replicon types. Molecular analysis of variance using the RAPD data showed thatE. coliisolates are nonrandomly distributed among different gut regions, and that gut region accounted for 25% (P< 0.001) of the observed variation among strains. Bacteriocin screening revealed that a bacteriocin gene was detected in 45% of the isolates, with 43% carrying colicin genes and 3% carrying microcin genes. Of the bacteriocins observed (H47, E3, E1, E2, E7, Ia/Ib, and B/M), the frequency with which they were detected varied with respect to gut region for the colicins E2, E7, Ia/Ib, and B/M. The plasmid replicon typing gave rise to 25 profiles from the 13 Inc types detected. Inc F types were detected most frequently, followed by Inc HI1 and N types. Of the Inc types detected, 7 were nonrandomly distributed among isolates from the different regions of the gut. The results of this study indicate that not only may the different regions of the gastrointestinal tract harbor different strains ofE. colibut also that strains from different regions have different characteristics.

scholarly journals Prevalence and molecular characterization of Shiga toxin-producing escherichia coli isolates from human and sheep in Al-Madinah Al-Munawarah

Infectio ◽  
2017 ◽  
Vol 21 (2) ◽  
Author(s):  
Eman Fathi Sharafa ◽  
Iman I. Shabanaa
Keyword(s):  
Escherichia Coli ◽  
Foodborne Pathogens ◽  
Shiga Toxin ◽  
Genetic Relatedness ◽  
Control Measures ◽  
Health Concern ◽  
Global Public Health ◽  
E Coli ◽  
Life Threatening

Shiga toxin-producing Escherichia coli (STEC) strains have emerged as important foodborne pathogens of global public health concern, causing life-threatening diseases. Sheep and their products have been documented as important reservoirs for STECs, especially E. coli O157. The aim of this study was to investigate STECs from diarrheal human and sheep in Al-Madinah Al-Munawarah, Saudi Arabia. Fecal samples were collected between June and August, 2015 from diarrheal humans (n = 134) and sheep (n = 87). Presumptive E. coli human-and sheep-isolated strains were identified for their serotypes, the associated virulence genes (Shiga toxin [stx1 , stx2 ], haemolysin [ehxA] and intimin [eae]) by polymerase chain reaction and their susceptibility to antibiotics. Pulsed-field gel electrophoresis (PFGE) was used to demonstrate the genetic relatedness between Serotype O157:H7 human- and sheep-isolated strains. Forty eight (48/221; 21.7%) STECs were recovered from both human and sheep, their serotypes were as follows: O157:H7, O26:H11, O157:HNM, O26:HNM, O128:H2, O48:HNM, O111:HNM and OUT:HUT. Various virulence profiles and multiple antibiotic resistance were observed among the isolates. Twenty eight O157:H7 serotypes (17 human isolates and 11 sheep isolates) were identified in 13 PFGE pulsotypes, where human and sheep isolates were highly related. PFGE banding profiles together with serotypes and genotypes afford proof that human and sheep can be colonized and infected with similar E. coli O157:H7 strains. Our findings highlight the importance of epidemiological and microbiological surveillance of STECs; as well as the development of control measures to decrease risks associated with zoonotic O157:H7.

scholarly journals Within-a-Day Detection and Rapid Characterization of Carbapenemase by Use of a New Carbapenem Inactivation Method-Based Test, CIMplus

2018 ◽  
Vol 56 (9) ◽  
Author(s):  
François Caméléna ◽  
Aurélie Cointe ◽  
Vincent Mathy ◽  
Claire Hobson ◽  
Catherine Doit ◽  
...  
Keyword(s):  
Test Performance ◽  
Antimicrobial Treatment ◽  
Control Measures ◽  
Decision Algorithm ◽  
Content Type ◽  
Infection Control Measures ◽  
Carbapenem Resistant ◽  
Culture Duration ◽  
Rapid Characterization

ABSTRACT The dissemination of carbapenemase-producing Enterobacteriaceae (CPE) is a major threat to public health. Rapid and accurate detection of CPE is essential for initiating appropriate antimicrobial treatment and establishing infection control measures. The carbapenem inactivation method (CIM), which has good sensitivity and specificity but a detection time of 20 h, was recently described. In this study, we evaluated the performances of a new version, the CIMplus test, which allows detection of carbapenemases in 8 h and characterization of carbapenemase classes, according to the Ambler classification, in 20 h. A panel of 110 carbapenem-resistant Enterobacteriaceae strains, including 92 CPE strains (with NDM, VIM, IMP, KPC, GES, OXA-48, and OXA-48-like enzymes), was used to evaluate test performance. Carbapenemase activity was detected at 8 h and 20 h. Characterization of carbapenemase classes, using specific inhibitors, was possible in 20 h. The CIMplus test had sensitivities of 95.7% and 97.8% at 8 h and 20 h, respectively, and a specificity of 94.4%, independent of the culture duration. Using a decision algorithm, this test was successful in identifying the carbapenemase class for 98.9% of tested CPE isolates (87/88 isolates). In total, the characterization was correct for 100%, 96.9%, and 100% of Ambler class A, B, and D isolates, respectively. Therefore, this test allows detection of carbapenemase activity in 8 h and characterization of carbapenemase classes, according to the Ambler classification, in 20 h. The CIMplus test represents a simple, affordable, easy-to-read, and accurate tool that can be used without any specific equipment.

scholarly journals High Prevalence of blaCTX-M-15 Gene among Extended-Spectrum β-Lactamase-Producing Escherichia coli Isolates Causing Extraintestinal Infections in Bangladesh

Antibiotics ◽  
2020 ◽  
Vol 9 (11) ◽  
pp. 796
Author(s):  
Razib Mazumder ◽  
Ahmed Abdullah ◽  
Dilruba Ahmed ◽  
Arif Hussain
Keyword(s):  
Escherichia Coli ◽  
Carbapenem Resistance ◽  
Multidrug Resistant ◽  
Control Measures ◽  
E Coli ◽  
Infection Control Measures ◽  
Extended Spectrum ◽  
Virulence Potential ◽  
High Prevalence ◽  
High Virulence

The emergence of multidrug-resistant (MDR) Escherichia coli (E. coli) clonal lineages with high virulence potential is alarming. Lack of sufficient data on molecular epidemiology of such pathogens from countries with high infection burden, such as Bangladesh, hinders management and infection control measures. In this study, we assessed the population structure, virulence potential and antimicrobial susceptibility of clinical E. coli isolates from Dhaka, Bangladesh. A high prevalence of MDR (69%) and extended-spectrum β-lactamase production (ESBL) (51%) was found. Most E. coli isolates were susceptible to amikacin (95%), meropenem (94%) and nitrofurantoin (89%) antibiotics. A high prevalence of ST131 (22%) and ST95 (9%) followed by ST69 (4%) and ST73 (3%) was observed. Phylogroups B2 (46%), B1 (16%), D (10%) and F (9%) were prominent. blaCTX-M-15 (52%) and blaNDM-1 (5%) were the most prevalent ESBL and carbapenem resistance genes, respectively. Moreover, the predominant pathotype identified was extraintestinal pathogenic E. coli (ExPEC) (41%) followed by enteric pathogens (11%). In conclusion, our results suggest the transmission of clonal E. coli groups amidst diverse E. coli population that are associated with high virulence potential and MDR phenotype. This is of high concern and mandates more efforts towards molecular surveillance of antimicrobial resistance (AMR) in clinically significant pathogens.

scholarly journals Genomic Characterization of MDR Escherichia coli Harboring blaOXA-48 on the IncL/M-type Plasmid Isolated from Blood Stream Infection

2018 ◽  
Vol 2018 ◽  
pp. 1-8 ◽  
Author(s):  
S. Alousi ◽  
T. Salloum ◽  
H. Arabaghian ◽  
G. M. Matar ◽  
G. F. Araj ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Blood Stream Infection ◽  
Genomic Analysis ◽  
Blood Stream ◽  
Population Movements ◽  
E Coli ◽  
Resistance Determinants ◽  
Genomic Characterization ◽  
Hospital Acquired

Escherichia coli is responsible for a wide variety of community and hospital acquired extraintestinal infections, and the emergence of ESBL resistant isolates is a major clinical concern. In this study, we characterized the genomic attributes of an OXA-48 and CTX-M-3 producing E. coli EC-IMP153. Whole-genome initial assembly produced 146 contigs with a combined 5,504,170 bp in size and a G+C content of 50.5%. wgSNPs-based phylogenetic comparison with 36 publically available genomes was also performed. Comprehensive genomic analysis showed that EC-IMP153 belonged to sequence type ST-405 and harbored several resistance determinants including the β-lactam resistance genes blaOXA-48, blaCTX-M-3, blaTEM-1B, blaOXA-1, and blaCMY-70, aminoglycoside fyuA and aac(3)IId, tetracycline tet(A) and tet(R), and fluoroquinolone gyrA, parC, and mfd resistance determinants. Plasmids with the following incompatibility groups were detected in silico and confirmed using PBRT: IncI1-α, IncL, IncW, Col (BS512), and IncF. To our knowledge this is the first in-depth genomic analysis of an OXA-48 producing E. coli ST-405 isolated from a patient in Lebanon and linked to a blood stream infection. Continuous monitoring is necessary to better understand the continued diffusion of such pathogens, especially in view of the population movements triggered by unrest in the Middle East.

scholarly journals Molecular Characterization of β-Lactamase Producing Genes and Integrons in Diarrheagenic Escherichia Coli From Diarrheal Children Less Than Five Years of Age in Ouagadougou, Burkina Faso.

2021 ◽  
Author(s):  
Rene Dembele ◽  
Wendpoulomdé A.D. Kaboré ◽  
Issiaka Soulama ◽  
Oumar Traoré ◽  
Nafissatou Ouédraogo ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Molecular Characterization ◽  
Resistance Genes ◽  
Antibiotic Resistance Genes ◽  
Control Measures ◽  
Diffusion Method ◽  
Biochemical Tests ◽  
Disk Diffusion Method ◽  
E Coli

Abstract Background The aim of this study was to determine the resistance of diarrheagenic Escherichia coli strains to β-lactams antibiotics and to perform the molecular characterization of Extended Spectrum β-lactamases (ESBL) and integrons genes. Methods This study was carried out from August 2013 to October 2015 and involved 31 DEC strains isolated from diarrheal stools samples collected from children less than five years of age. The identification and characterization of DEC strains was done through the standard biochemical tests those were confirmed using API 20E and Polymerase Chain Reaction (PCR). The determination of antimicrobial resistance was realized by the disk diffusion method then an amplification of the β-lactamase resistance genes and integrons by PCR was done. Results Out of the 419 E. coli strains identified, 31 isolates (7.4%) harbored the DEC virulence genes. From these DEC, 21 (67.7%) were ESBL-producing E. coli. Susceptibility to ESBL-producing E. coli showed that the majority of isolates were highly resistant to amoxicillin (77.4%), amoxicillin clavulanic acid (77.4%) and piperacillin (64.5%). The following antibiotic resistance genes and integron were identified from the 31 DEC isolates: blaTEM (6.5%), blaSHV (19.4%), blaOXA (38.7%) blaCTX−M (9.7%), Int1 (58.1%) and Int3 (19.4%). No class 2 integrons (Int2) was characterized. Conclusions Because of the high prevalence of multidrug-resistant ESBL organisms found in this study among pediatric patients, there is a need of stringent pediatric infection control measures.

scholarly journals Dissemination of Blandm-5 in Escherichia Coli via the Incx3 Plasmid From Different Regions in China

2021 ◽  
Author(s):  
Xiaofeng Hu ◽  
Lang Yang ◽  
Nian Dong ◽  
Yanfeng Lin ◽  
Ling Zhang ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Blot Hybridization ◽  
Carbapenem Resistance ◽  
Southern Blot Hybridization ◽  
Control Measures ◽  
Rrna Gene ◽  
Limited Information ◽  
E Coli ◽  
Carbapenem Resistant ◽  
Antimicrobial Resistance Genes

Abstract Background: Recently, the spread of NDM-5-producing Escherichia coli has become a severe challenge in clinical therapy, which necessitates reliable detection and surveillance methods. However, limited information is available regarding the prevalence and dissemination of the blaNDM-5 gene in Escherichia coli in China. Therefore, we investigated the dissemination of the blaNDM-5 gene in carbapenem-resistant Escherichia coli isolates from different regions in China.Methods: A total of 1,180 carbapenem-resistant enterobacteriaceae strains were obtained from patients admitted to the 20 sentinel hospitals in eight cities. Strains positive for blaNDM-5 were detected using the Vitek 2 compact system, 16S rRNA gene sequencing, PCR, the S1-pulsed-field gel electrophoresis assay, and Southern blot hybridization. The horizontal-transfer capability of the blaNDM gene was assessed by filter mating with a standard E. coli J53 azide-resistant strain as the recipient. Genotyping, susceptibility testing, and whole genome sequencing were performed. Results: Seven strains of blaNDM-5-positive E.coli was detected in 1180 clinical strains from different regions in China. The blaNDM-5-carrying strains showed resistance to multiple tested antibiotics and belonged to two widespread sequence types, ST167 and ST405. Antimicrobial resistance genes including blaCTX-M, blaOXA, blaCMY, and two novel blaTEM variants (blaTEM-230 and blaTEM-231) were also identified. Southern blotting located the blaNDM-5 gene on 46-kb IncX3 plasmids in all isolates, which showed only two single nucleotide differences between EJN003 and the other strains. Conclusions: This study further confirms the increasing occurrence of blaNDM-5-carrying IncX3 plasmids and the dissemination of carbapenem resistance in E. coli isolates via the plasmid from different parts in China, which warrants stringent surveillance and control measures.

scholarly journals Co-Occurrence of Plasmid-Mediated AmpC β-Lactamase Activity Among Klebsiella pneumoniae and Escherichia Coli

2017 ◽  
Vol 11 (1) ◽  
pp. 195-202 ◽  
Author(s):  
Abdulaziz Zorgani ◽  
Hiyam Daw ◽  
Najib Sufya ◽  
Abdullah Bashein ◽  
Omar Elahmer ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Klebsiella Pneumoniae ◽  
Multidrug Resistant ◽  
Control Measures ◽  
Gene Encoding ◽  
E Coli ◽  
Infection Control Measures ◽  
Genes Encoding ◽  
Polymerase Chain ◽  
Variant Enzyme

Introduction: Extended-spectrum β-lactamases (ESBLs), including the AmpC type, are important mechanisms of resistance among Klebsiella pneumoniae and Escherichia coli isolates. Objective: The aim of the study was to investigate the occurrence of AmpC-type β-lactamase producers isolated from two hospitals in Tripoli, Libya. Methods: All clinical isolates (76 K. pneumoniae and 75 E. coli) collected over two years (2013-2014) were evaluated for susceptibility to a panel of antimicrobials and were analyzed phenotypically for the ESBL and AmpC phenotype using E-test and ESBL and AmpC screen disc test. Both ESBL and AmpC-positive isolates were then screened for the presence of genes encoding plasmid-mediated AmpC β-lactamases by polymerase chain reaction (PCR). Results: Of the K. pneumoniae and E. coli tested, 75% and 16% were resistant to gentamicin, 74% and 1.3% to imipenem, 71% and 12% to cefoxitin, 80% and 12% to cefepime, 69% and 22.6% to ciprofloxacin, respectively. None of the E. coli isolates were multidrug resistant compared with K. pneumoniae (65.8%). K. pneumoniae ESBL producers were significantly higher (85.5%) compared with (17.3%) E. coli isolates (P <0.0001, OR=4.93). Plasmid-mediated AmpC genes were detected in 7.9% of K. pneumoniae, and 4% E. coli isolates. There was low agreement between phenotypic and genotypic methods, phenotypic testing underestimated detection of AmpC enzyme and did not correlate well with molecular results. The gene encoding CMY enzyme was the most prevalent (66.6%) of AmpC positive isolates followed by MOX, DHA and EBC. Only one AmpC gene was detected in 5/9 isolates, i.e, blaCMY (n=3), bla MOX (n=1), blaDHA (n=1). However, co-occurrence of AmpC genes were evident in 3/9 isolates with the following distribution: bla CMY and blaEBC (n=1), and blaCMY and blaMOX (n=2). Neither blaFOX nor blaACC was detected in all tested isolates. All AmpC positive strains were resistant to cefoxitin and isolated from patients admitted to intensive care units. Conclusion: Further studies are needed for detection of other AmpC variant enzyme production among such isolates. Continued surveillance and judicious antibiotic usage together with the implementation of efficient infection control measures are absolutely required.

Genomic characterization of 16S rRNA methyltransferase-producing Escherichia coli isolates from the Parisian area, France

2020 ◽  
Vol 75 (7) ◽  
pp. 1726-1735 ◽  
Author(s):  
François Caméléna ◽  
Florence Morel ◽  
Manel Merimèche ◽  
Jean-Winoc Decousser ◽  
Hervé Jacquier ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
16S Rrna ◽  
Genomic Diversity ◽  
Health Concern ◽  
M Gene ◽  
Genetic Environment ◽  
E Coli ◽  
Genomic Characterization ◽  
High Level

Abstract Background The resistance to all aminoglycosides (AGs) conferred by 16S rRNA methyltransferase enzymes (16S-RMTases) is a major public health concern. Objectives To characterize the resistance genotype, its genetic environment and plasmid support, and the phylogenetic relatedness of 16S-RMTase-producing Escherichia coli from France. Methods We screened 137 E. coli isolates resistant to all clinically relevant AGs from nine Parisian hospitals for 16S-RMTases. WGS was performed on clinical isolates with high-level AG resistance (MIC ≥256 mg/L) and their transformants. Results Thirty of the 137 AG-resistant E. coli produced 16S-RMTases: 11 ArmA, 18 RmtB and 1 RmtC. The 16S-RMTase producers were also resistant to third-generation cephalosporins (90% due to a blaCTX-M gene), co-trimoxazole, fluoroquinolones and carbapenems (blaNDM and blaVIM genes) in 97%, 83%, 70% and 10% of cases, respectively. Phylogenomic diversity was high in ArmA producers, with 10 different STs, but a similar genetic environment, with the Tn1548 transposon carried by a plasmid closely related to pCTX-M-3 in 6/11 isolates. Conversely, RmtB producers belonged to 12 STs, the most frequent being ST405 and ST complex (STc) 10 (four and four isolates, respectively). The rmtB gene was carried by IncF plasmids in 10 isolates and was found in different genetic environments. The rmtC gene was carried by the pNDM-US plasmid. Conclusions ArmA and RmtB are the predominant 16S-RMTases in France, but their spread follows two different patterns: (i) dissemination of a conserved genetic support carrying armA in E. coli with high levels of genomic diversity; and (ii) various genetic environments surrounding rmtB in clonally related E. coli.

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