# | Rank | Similarity | Title + Abs. | Year | PMID |
|---|---|---|---|---|---|
| 0 | 1 | 2 | 3 | 4 | 5 |
| 1639 | 0 | 1.0000 | Multidrug-resistant Klebsiella quasipneumoniae subsp. similipneumoniae carrying bla(NDM)-bla(CTX-M15) isolated from flies in Rio de Janeiro, Brazil. OBJECTIVES: Flies have been implicated in the dispersal of medically important bacteria including members of the genus Klebsiella between different environmental compartments. The aim of this study was to retrieve and characterize antibiotic-resistant bacteria from flies collected near to hospitals. METHODS: Flies were collected in the vicinity of medical facilities and examined for bacteria demonstrating phenotypic resistance to ceftriaxone, followed by determination of phenotypic and genotypic resistance profiles. In addition, whole genome sequencing followed by phylogenetic analysis and resistance genotyping were performed with the multidrug-resistant (MDR) strain Lemef23, identified as Klebsiella quasipneumoniae subsp. similipneumoniae. RESULTS: The strain Lemef23, classified by multiple locus sequence typing as novel ST 3397, harboured numerous resistance genes. The bla(NDM) was located on a Tn3000 element, a common genetic platform for the carriage of this gene in Brazil. Inference of phylogenetic orthology of strain Lemef23 and other clinical isolates suggested an anthropogenic origin. CONCLUSIONS: The findings of this study support the role of flies as vectors of MDR bacteria of clinical importance and provide the first record of bla(NDM-1) and bla(CTXM-15) in a Brazilian isolate of K. quasipneumoniae subsp. similipneumoniae, demonstrating the value of surveying insects as reservoirs of antibiotic resistance. | 2021 | 33302000 |
| 1632 | 1 | 0.9997 | Klebsiella spp. carried by insects as a reservoir of virulence and resistance to antimicrobials. Synanthropic flies contribute to the transport of pathogens between environments, but their role remains underexplored. Previously, our group described 197 bacterial strains obtained from 117 dipterous muscoids collected nearby hospitals in Rio de Janeiro, 35 % showing antimicrobial resistance. Ten isolates belonged to Klebsiella genus. Klebsiella pneumoniae is a threat to human health due to high resistance and virulence. We characterized the 10 isolates from the genus Klebsiella isolated from flies, comparing to 4 from patients. Most carried resistance determinants as bla (SHV) and bla (NDM). One of them was MDR. Isolates from flies included ST219 and ST76, clinically relevant. Efflux pumps and porins were sporadically encoded in both fly and clinical samples. Among 10 virulence determinants, fly-isolated strains presented from 2 to 7 genes, while clinical strains ranged from 4 to 6. Notably, fly-isolated formed higher biofilm than clinical. Our findings underline that environmental resistance reservoirs may undermine efforts to control AMR. | 2025 | 40630107 |
| 1858 | 2 | 0.9996 | Molecular Characteristics of Antimicrobial Resistance and Virulence in Klebsiella pneumoniae Strains Isolated from Goose Farms in Hainan, China. We retrospectively investigated 326 samples that were collected from goose farms in Hainan Province, China, in 2017. A total of 33 carbapenem-resistant Klebsiella pneumoniae (CRKP) isolates were identified from 326 samples, and the 33 CRKP isolates were characterized based on whole-genome sequencing (WGS) data from the Illumina and Oxford Nanopore Technologies (ONT) platforms. All of these 33 CRKP isolates possessed bla(NDM-5), and a single isolate coharbored mcr-1 and bla(NDM-5), while 4 isolates carried multiple virulence and metal tolerance gene clusters. One CRKP strain (CMG-35-2) was selected for long sequence reading. A hybrid plasmid carrying the virulence, resistance, and metal resistance gene in the strain was found. It possessed 2 backbones [IncFIB(K)-IncFII(K)] within a single plasmid that were closely related to K. pneumoniae plasmids from a human-associated habitat in the United States and from a human isolate in Hong Kong. A mouse abdominal infection model indicated that that strain was of the moderate virulence phenotype. This study revealed that K. pneumoniae on goose farms is an important reservoir for bla(NDM-5) and these bacteria are represented by a diversity of sequence types. The heterozygous multiple drug resistance genes carried on plasmids highlighted the genetic complexity of CRKP and the urgent need for continued active surveillance. IMPORTANCE CRKP is one of the most important pathogens, which can cause infection not only in humans but also in waterfowl. The discovery of bla(NDM-5)-producing K. pneumoniae in waterfowl farms in recent years suggests that waterfowl are an important reservoir for bla(NDM-5)-producing Enterobacteriaceae. However, there are few studies on the spread of bla(NDM-5)-producing bacteria in waterfowl farms. Our study showed that the IncX3 plasmid carrying bla(NDM-5) in goose farms is widely present in K. pneumoniae isolates and a large number of resistance genes are accumulated in it. We found a transferable IncFIB-FII hybrid plasmid that combines virulence, resistance, and metal resistance genes, which allow transfer of these traits between bacteria in different regions. The results of this study contribute to a better understanding of the prevalence and transmission of carbapenem-resistant K. pneumoniae in goose farms. | 2022 | 35389252 |
| 1647 | 3 | 0.9996 | Genomic and antimicrobial resistance genes diversity in multidrug-resistant CTX-M-positive isolates of Escherichia coli at a health care facility in Jeddah. BACKGROUND: Whole genome sequencing has revolutionized epidemiological investigations of multidrug-resistant pathogenic bacteria worldwide. Aim of this study was to perform comprehensive characterization of ESBL-positive isolates of Escherichia coli obtained from clinical samples at the King Abdulaziz University Hospital utilizing whole genome sequencing. METHODS: Isolates were identified by MALDI-TOF mass spectrometry. Genome sequencing was performed using a paired-end strategy on the MiSeq platform. RESULTS: Nineteen isolates were clustered into different clades in a phylogenetic tree based on single nucleotide polymorphisms in core genomes. Seventeen sequence types were identified in the extended-spectrum β-lactamase (ESBL)-positive isolates, and 11 subtypes were identified based on distinct types of fimH alleles. Forty-one acquired resistance genes were found in the 19 genomes. The bla(CTX-M-15) gene, which encodes ESBL, was found in 15 isolates and was the most predominant resistance gene. Other antimicrobial resistance genes (ARGs) found in the isolates were associated with resistance to tetracycline (tetA), aminoglycoside [aph(3″)-Ib, and aph(6)-Id], and sulfonamide (sul1, and sul2). Nonsynonymous chromosomal mutations in the housekeeping genes parC and gyrA were commonly found in several genomes. CONCLUSION: Several other ARGs were found in CTX-M-positive E. coli isolates confer resistance to clinically important antibiotics used to treat infections caused by Gram-negative bacteria. | 2020 | 31279801 |
| 1682 | 4 | 0.9996 | Multidrug-Resistant and Clinically Relevant Gram-Negative Bacteria Are Present in German Surface Waters. Water is considered to play a role in the dissemination of antibiotic-resistant Gram-negative bacteria including those encoding Extended-spectrum beta-lactamases (ESBL) and carbapenemases. To investigate the role of water for their spread in more detail, we characterized ESBL/Carbapenemase-producing bacteria from surface water and sediment samples using phenotypic and genotypic approaches. ESBL/Carbapenemase-producing isolates were obtained from water/sediment samples. Species and antibiotic resistance were determined. A subset of these isolates (n = 33) was whole-genome-sequenced and analyzed for the presence of antibiotic resistance genes and virulence determinants. Their relatedness to isolates associated with human infections was investigated using multilocus sequence type and cgMLST-based analysis. Eighty-nine percent of the isolates comprised of clinically relevant species. Fifty-eight percent exhibited a multidrug-resistance phenotype. Two isolates harbored the mobile colistin resistance gene mcr-1. One carbapenemase-producing isolate identified as Enterobacter kobei harbored bla (VIM-) (1). Two Escherichia coli isolates had sequence types (ST) associated with human infections (ST131 and ST1485) and a Klebsiella pneumoniae isolate was classified as hypervirulent. A multidrug-resistant (MDR) Pseudomonas aeruginosa isolate encoding known virulence genes associated with severe lung infections in cystic fibrosis patients was also detected. The presence of MDR and clinically relevant isolates in recreational and surface water underlines the role of aquatic environments as both reservoirs and hot spots for MDR bacteria. Future assessment of water quality should include the examination of the multidrug resistance of clinically relevant bacterial species and thus provide an important link regarding the spread of MDR bacteria in a One Health context. | 2019 | 31849911 |
| 1008 | 5 | 0.9996 | Antimicrobial resistance of Escherichia coli, Enterobacter spp., Klebsiella pneumoniae and Enterococcus spp. isolated from the feces of giant panda. BACKGROUND: Escherichia coli, Enterobacter spp., Klebsiella pneumoniae and Enterococcus spp., common gut bacteria in giant pandas, include opportunistic pathogens. The giant panda is an endangered species, classified as vulnerable by the World Wildlife Foundation. Continuous monitoring for the emergence of antimicrobial resistance (AMR) among bacterial isolates from giant pandas is vital not only for their protection but also for public health. RESULTS: A total of 166 E. coli, 68 Enterobacter spp., 116 K. pneumoniae and 117 Enterococcus spp. isolates were collected from fecal samples of 166 giant pandas. In the antimicrobial susceptibility tests, 144 E. coli isolates, 66 Enterobacter spp. isolates, 110 K. pneumoniae isolates and 43 Enterococcus spp. isolates were resistant to at least one antimicrobial. The resistant isolates carried antimicrobial resistance genes (ARGs), including sul3, bla(TEM), bla(SHV) and tetA. The differences in the prevalence of the bla types implied that the genetic basis for β-lactam resistance among the E. coli, Enterobacter spp. and K. pneumoniae isolates was different. The strain K. pneumoniae K85 that was resistant to sixteen antimicrobials was selected for whole genome sequencing. The genome contained Col440I, IncFIB(K) and IncFII(K) plasmids and altogether 258 ARGs were predicted in the genome; 179 of the predicted ARGs were efflux pump genes. The genetic environment of the β-lactamase genes bla(CTX-M-3) and bla(TEM-1) in the K. pneumoniae K85 genome was relatively similar to those in other sequenced K. pneumoniae genomes. In comparing the giant panda age groups, the differences in the resistance rates among E. coli, K. pneumoniae and Enterobacter spp. isolates suggested that the infections in giant pandas of different age should be treated differently. CONCLUSIONS: Antimicrobial resistance was prevalent in the bacterial isolates from the giant pandas, implying that the gut bacteria may pose serious health risks for captive giant pandas. The resistance genes in the genome of K. pneumoniae K85 were associated with insertion sequences and integron-integrase genes, implying a potential for the further spread of the antimicrobial resistance. | 2022 | 35421931 |
| 1648 | 6 | 0.9996 | Molecular characterization of the multi-drug resistant Myroides odoratimimus isolates: a whole genome sequence-based study to confirm carbapenem resistance. The bacteria belonging to the Myroides genus are opportunistic pathogens causing community or hospital-acquired infections that result in treatment failure due to antibiotic resistance. This study aimed to investigate molecular mechanisms of antibiotic resistance, clonal relatedness, and the biofilm forming capacity of the 51 multi-drug resistant Myroides odoratimimus. All isolates were screened for bla(KPC), bla(OXA), bla(VIM), bla(IMP), bla(MUS), bla(TUS), bla(NDM), and bla(B) genes by using PCR amplification. Whole genome sequencing (WGS) was applied on three randomly selected isolates for further investigation of antibiotic resistance mechanisms. Clonal relatedness was analyzed by Pulsed-field gel electrophoresis (PFGE) and the microtiter plate method was used to demonstrate biofilm formation. All isolates were positive for biofilm formation. PCR analysis resulted in a positive for only the bla(MUS-1) gene. WGS identified bla(MUS-1), erm(F), ere(D), tet(X), and sul2 genes in all strains tested. Moreover, the genomic analyses of three strains revealed that genomes contained a large number of virulence factors (VFs). PFGE yielded a clustering rate of 96%. High clonal relatedness, biofilm formation, and multi-drug resistance properties may lead to the predominance of these opportunistic pathogens in hospital environments and make them cause nosocomial infections. | 2024 | 38127105 |
| 908 | 7 | 0.9996 | Multidrug-resistant Raoultella ornithinolytica misidentified as Klebsiella oxytoca carrying blaOXA β-lactamases: antimicrobial profile and genomic characterization. Class D β-lactamases OXA-232 and OXA-48 hydrolyze penicillin, cephalosporins and carbapenems, limiting the pharmacological therapeutics in bacteraemia. OXA producer microorganisms are considered a great emergent threat, especially in nosocomial environments. To determine the resistance profile and genomic characterization of two isolates initially identified as potential carbapenemase-producer Klebsiella oxytoca in a third level hospital. Automated platform BD Phoenix-100 System was used to identify and to biochemically characterize both isolates. Furthermore, the resistance profile was determined through CLSI methods and the whole genome sequences were obtained using Next-Generation Sequencing. Resistance genes were analyzed, and the virtual fingerprinting was determined to corroborate the similarity with related bacteria. Both strains correspond to Raoultella ornithinolytica carrying OXA 232 and OXA-48 genes, confirming the class D β-lactamases assay results. Here, we present the genetic and phenotypic analysis of multidrug resistance R. ornithinolytica, representing the first report in Mexico. | 2021 | 34499216 |
| 1646 | 8 | 0.9996 | Draft genome analysis of a multidrug-resistant Pseudomonas aeruginosa CMPL223 from hospital wastewater in Dhaka, Bangladesh. OBJECTIVES: Multidrug-resistant (MDR) clones of Pseudomonas aeruginosa can cause complicated infections in human. The emergence of ST664 of MDR P. aeruginosa has been reported in Nepal, Iran and China. Here, we present the draft genome analysis of a MDR P. aeruginosa CMPL223 isolated from hospital wastewater in Bangladesh to understand antimicrobial resistance trends and pathogenicity. METHODS: Cetrimide agar was used for isolation of P. aeruginosa. Polymerase chain reaction (PCR) was carried out for detection of biofilm and integron related genes. Bacterial susceptibility to antibiotics was determined by disc diffusion method. Sequencing of whole genomic DNA was performed using Illumina iSeq 100 platform. Following quality checking of raw reads, assembly and annotation of sequences, a wide array of in silico tools were used for characterization of draft genome. RESULTS: The isolate was a strong biofilm former, carried integron 1 in chromosomal DNA, and was predicted to be pathogenic. It belongs to sequence type ST664 and O7 serogroup. The assembled genome contained 12 acquired antimicrobial resistant (AMR) genes, 2 prophage regions, 240 virulence genes, 71 drug targets, 142 insertion sequences, and 1 CRISPR (Clustered Regularly Interspaced Short Palindromic Repeats) array. The isolate was resistant to 21 out of 23 antibiotics, except colistin and imipenem. Comprehensive Antibiotic Resistance Database and ResFinder revealed that bacteria harboured bla(OXA-50), bla(OXA-796), bla(PDC-374,) fosA, tet(G), sul1, catB7, aph(3')-iib and ant(4')-IIb genes, conferring resistance to different classes of antibiotics. The results of in vitro characterization were consistent with the possible expression of detected antibiotic resistant genes through in silico analysis. CONCLUSION: Our data suggested the emergence of MDR P. aeruginosa ST664, which needs control measures for limiting its dissemination. | 2022 | 35793775 |
| 1631 | 9 | 0.9996 | Surveillance of antimicrobial resistant bacteria in flies (Diptera) in Rio de Janeiro city. Antimicrobial-resistant bacteria were isolated from muscoid dipterans collected at five different areas of Rio de Janeiro city, in proximity to hospitals. Extracts obtained by maceration of flies were diluted and used as inocula for different culture media, with or without antibiotic (ceftriaxone 1 mg/L) supplementation. Purified isolates were submitted to antimicrobial susceptibility testing (AST). Bacterial identification was performed by MALDI TOF Microflex LT (Bruker Daltonics). A total of 197 bacterial strains were obtained from 117 dipterous muscoids. Forty-two flies (35.9%) carried bacteria resistant to at least one antimicrobial, while 7 insects (5.9%) carried multidrug-resistant bacteria (MDR), which were all members of the family Enterobacteriaceae. Among 10 MDR bacteria (5%), 5 strains (2,5%) were positive by PCR for one or more of the following antibiotic resistance genes: aac(6')-Ib, bla(TEM-1), bla(CTX-M-15), bla(KPC-2) and bla(NDM-1). Analysis of variance (ANOVA) and cluster analysis compared the number of resistant isolates per collection point and showed that a single location was statistically different from the others with regard to resistance. Although there are still no criteria to determine the environmental contamination by resistant bacteria the fact that they have been isolated from flies is an indication of a disseminated contamination. As such, these insects may be useful in monitoring programs of antibiotic resistance in non-hospital environments, where they could function as sentinels. | 2021 | 34029528 |
| 876 | 10 | 0.9996 | Surveillance and Genomic Characterisation of Colistin-Resistant Gram-Negative Bacteria in the Drains of High-Risk Hospital Units. OBJECTIVE: The health care water environment, including sinks and drainage systems, can be a long-term reservoir of nosocomial pathogens. In this study, we aimed to investigate the presence of colistin-resistant Gram-negative (ColR-GN) bacteria in humid compartments of high-risk hospital units at the University Medical Center Groningen, The Netherlands. METHODS: Environmental sampling was conducted in sink and shower drains of high-risk hospital units, and colistin MICs were determined using broth microdilution. Whole-genome sequencing was performed to investigate the presence of mobile colistin resistance (mcr) genes, chromosomal point mutations and gene alterations linked to colistin resistance. RESULTS: ColR-GN bacteria were detected in all investigated units, with Enterobacter spp. being the most abundant genus. Twelve isolates exhibited colistin resistance (MIC >2 mg/L), including Enterobacter cloacae complex (n = 11) and Klebsiella pneumoniae (n = 1). Chromosomal mutations in genes involved in lipopolysaccharide structure modifications were the main mechanisms contributing to colistin resistance in Enterobacter spp. and Klebsiella spp. (91.6%, 11/12). Additionally, two Enterobacter kobei isolates harboured mobile colistin resistance genes, mcr-4.3 and mcr-9.1. CONCLUSIONS: The presence and persistence of bacterial ColR-GN clones in the sink and shower drains of high-risk hospital units highlights the importance of monitoring such environments for antibiotic-resistant bacteria to identify reservoirs and prevent further spread. | 2025 | 39993598 |
| 1856 | 11 | 0.9996 | Whole-Genome Sequencing-Based Species Classification, Multilocus Sequence Typing, and Antimicrobial Resistance Mechanism Analysis of the Enterobacter cloacae Complex in Southern China. Members of the Enterobacter cloacae complex (ECC) are important opportunistic nosocomial pathogens that are associated with a great variety of infections. Due to limited data on the genome-based classification of species and investigation of resistance mechanisms, in this work, we collected 172 clinical ECC isolates between 2019 and 2020 from three hospitals in Zhejiang, China and performed a retrospective whole-genome sequencing to analyze their population structure and drug resistance mechanisms. Of the 172 ECC isolates, 160 belonged to 9 classified species, and 12 belonged to unclassified species based on ANI analysis. Most isolates belonged to E. hormaechei (45.14%) followed by E. kobei (13.71%), which contained 126 STs, including 62 novel STs, as determined by multilocus sequence typing (MLST) analysis. Pan-genome analysis of the two ECC species showed that they have an "open" tendency, which indicated that their Pan-genome increased considerably with the addition of new genomes. A total of 80 resistance genes associated with 11 antimicrobial agent categories were identified in the genomes of all the isolates. The most prevailing resistance genes (12/29, 41.38%) were related to β-lactams followed by aminoglycosides. A total of 247 β-lactamase genes were identified, of which the bla(ACT) genes were the most dominant (145/247, 58.70%), followed by the bla(TEM) genes (21/247, 8.50%). The inherent ACT type β-lactamase genes differed among different species. bla(ACT-2) and bla(ACT-3) were only present in E. asburiae, while bla(ACT-9), bla(ACT-12), and bla(ACT-6) exclusively appeared in E. kobei, E. ludwigii, and E. mori. Among the six carbapenemase-encoding genes (bla(NDM-1), bla(NDM-5), bla(IMP-1), bla(IMP-4), bla(IMP-26), and bla(KPC-2)) identified, two (bla(NDM-1) and bla(IMP-1)) were identified in an ST78 E. hormaechei isolate. Comparative genomic analysis of the carbapenemase gene-related sequences was performed, and the corresponding genetic structure of these resistance genes was analyzed. Genome-wide molecular characterization of the ECC population and resistance mechanism would offer valuable insights into the effective management of ECC infection in clinical settings. IMPORTANCE The presence and emergence of multiple species/subspecies of ECC have led to diversity and complications at the taxonomic level, which impedes our further understanding of the epidemiology and clinical significance of species/subspecies of ECC. Accurate identification of ECC species is extremely important. Also, it is of great importance to study the carbapenem-resistant genes in ECC and to further understand the mechanism of horizontal transfer of the resistance genes by analyzing the surrounding environment around the genes. The occurrence of ECC carrying two MBL genes also indicates that the selection pressure of bacteria is further increased, suggesting that we need to pay special attention to the emergence of such bacteria in the clinic. | 2022 | 36350178 |
| 1685 | 12 | 0.9996 | Molecular epidemiology and mechanisms of carbapenem and colistin resistance in Klebsiella and other Enterobacterales from treated wastewater in Croatia. Among the most problematic bacteria with clinical relevance are the carbapenem-resistant Enterobacterales (CRE), as there are very limited options for their treatment. Treated wastewater can be a route for the release of these bacteria into the environment and the population. The aim of this study was to isolate CRE from treated wastewater from the Zagreb wastewater treatment plant and to determine their phenotypic and genomic characteristics. A total of 200 suspected CRE were isolated, 148 of which were confirmed as Enterobacterales by MALDI-TOF MS. The predominant species was Klebsiella spp. (n = 47), followed by Citrobacter spp. (n = 40) and Enterobacter cloacae complex (cplx.) (n = 35). All 148 isolates were carbapenemase producers with a multidrug-resistant phenotype. Using multi-locus sequence typing and whole-genome sequencing (WGS), 18 different sequence types were identified among these isolates, 14 of which were associated with human-associated clones. The virulence gene analysis of the sequenced Klebsiella isolates (n = 7) revealed their potential pathogenicity. PCR and WGS showed that the most frequent carbapenemase genes in K. pneumoniae were bla(OXA-48) and bla(NDM-1), which frequently occurred together, while bla(KPC-2) together with bla(NDM-1) was mainly detected in K. oxytoca, E. cloacae cplx. and Citrobacter spp. Colistin resistance was observed in 40% of Klebsiella and 57% of Enterobacter isolates. Underlying mechanisms identified by WGS include known and potentially novel intrinsic mechanisms (point mutations in the pmrA/B, phoP/Q, mgrB and crrB genes) and acquired mechanisms (mcr-4.3 gene). The mcr-4.3 gene was identified for the first time in K. pneumoniae and is probably located on the conjugative IncHI1B plasmid. In addition, WGS analysis of 13 isolates revealed various virulence genes and resistance genes to other clinically relevant antibiotics as well as different plasmids possibly associated with carbapenemase genes. Our study demonstrates the important role that treated municipal wastewater plays in harboring and spreading enterobacterial pathogens that are resistant to last-resort antibiotics. | 2024 | 38479059 |
| 1708 | 13 | 0.9996 | High-level of resistance to β-lactam and presence of β-lactamases encoding genes in Ochrobactrum sp. and Achromobacter sp. isolated from soil. OBJECTIVES: Bacteria belonging to the genera Ochrobactrum and Achromobacter are bacteria considered opportunistic, causing infections mainly in immunocompromised patients. β-lactamases are the main cause of resistance to β-lactam antibiotics. This study aimed to investigate the antimicrobial resistance profile and the presence of β-lactamases encoding genes in Ochrobactrum sp. and Achromobacter sp. isolated from Brazilian soils. METHODS: Soil samples from the five regions of Brazil were collected for the isolation of bacteria, which were identified molecularly and then, the minimum inhibitory concentration and detection of β-lactamases encoding genes were performed. RESULTS: High-level of resistance to β-lactam antibiotics and different β-lactamases encoding genes were found (bla(CTX-M-Gp1), bla(SHV), bla(OXA-1-like) and bla(KPC)), including the first report of the presence of bla(KPC) in bacteria belonging to the genera Ochrobactrum and Achromobacter. CONCLUSION: The results showed that the bacteria from this study, belonging to genera Ochrobactrum and Achromobacter isolated from soil, harbor different β-lactamases encoding genes and can act as a reservoir of these genes. | 2017 | 29111479 |
| 883 | 14 | 0.9996 | Detection of plasmid-mediated colistin resistance, mcr-1 gene, in Escherichia coli isolated from high-risk patients with acute leukemia in Spain. BACKGROUND: Bacterial infections in immunocompromised patients are associated with a high mortality and morbidity rate. In this high-risk group, the presence of multidrug-resistant (MDR) bacteria, particularly bacteria that harbor a transferable antibiotic resistance gene, complicates the management of bacterial infections. In this study, we investigated the presence of the transferable colistin resistance mcr genes in patients with leukemia in Spain. METHODS: 217 fecal samples collected in 2013-2015 from 56 patients with acute leukemia and colonized with MDR Enterobacteriaceae strains, were screened on September 2017 for the presence of the colistin resistance mcr genes (mcr-1 to -5) by multiplex PCR. mcr positive strains selected on LBJMR and MacConkey supplemented with colistin (2 μg/ml) media were phenotypically and molecularly characterized by antimicrobial susceptibility testing, minimum inhibitory concentration, multilocus sequence typing and plasmid characterization. RESULTS: Among 217 fecal samples, 5 samples collected from 3 patients were positive for the presence of the mcr-1 colistin-resistance gene. Four Escherichia coli strains were isolated and exhibited resistance to colistin with MIC = 4 μg/ml. Other genes conferring the resistance to β-lactam antibiotics have also been identified in mcr-1 positive strains, including bla(TEM-206) and bla(TEM-98). Three different sequence types were identified, including ST1196, ST140 and ST10. Plasmid characterization allowed us to detect the mcr-1 colistin resistance gene on conjugative IncP plasmid type. CONCLUSION: To the best of our knowledge, we have identified the mcr-1 gene for the first time in leukemia patients in Spain. In light of these results, strict measures have been implemented to prevent its dissemination. | 2019 | 31023570 |
| 1683 | 15 | 0.9996 | Colonization of a hand washing sink in a veterinary hospital by an Enterobacter hormaechei strain carrying multiple resistances to high importance antimicrobials. BACKGROUND: Hospital intensive care units (ICUs) are known reservoirs of multidrug resistant nosocomial bacteria. Targeted environmental monitoring of these organisms in health care facilities can strengthen infection control procedures. A routine surveillance of extended spectrum beta-lactamase (ESBL) producers in a large Australian veterinary teaching hospital detected the opportunistic pathogen Enterobacter hormaechei in a hand washing sink of the ICU. The organism persisted for several weeks, despite two disinfection attempts. Four isolates were characterized in this study. METHODS: Brilliance-ESBL selective plates were inoculated from environmental swabs collected throughout the hospital. Presumptive identification was done by conventional biochemistry. Genomes of multidrug resistant Enterobacter were entirely sequenced with Illumina and Nanopore platforms. Phylogenetic markers, mobile genetic elements and antimicrobial resistance genes were identified in silico. Antibiograms of isolates and transconjugants were established with Sensititre microdilution plates. RESULTS: The isolates possessed a chromosomal Tn7-associated silver/copper resistance locus and a large IncH12 conjugative plasmid encoding resistance against tellurium, arsenic, mercury and nine classes of antimicrobials. Clusters of antimicrobial resistance genes were associated with class 1 integrons and IS26, IS903 and ISCR transposable elements. The blaSHV-12, qnrB2 and mcr-9.1 genes, respectively conferring resistance to cephalosporins, quinolones and colistin, were present in a locus flanked by two IS903 copies. ESBL production and enrofloxacin resistance were confirmed phenotypically. The isolates appeared susceptible to colistin, possibly reflecting the inducible nature of mcr-9.1. CONCLUSIONS: The persistence of this strain in the veterinary hospital represented a risk of further accumulation and dissemination of antimicrobial resistance, prompting a thorough disinfection of the ICU. The organism was not recovered from subsequent environmental swabs, and nosocomial Enterobacter infections were not observed in the hospital during that period. This study shows that targeted routine environmental surveillance programs to track organisms with major resistance phenotypes, coupled with disinfection procedures and follow-up microbiological cultures are useful to control these risks in sensitive areas of large veterinary hospitals. | 2020 | 33087168 |
| 1987 | 16 | 0.9996 | Plasmid sequence dataset of multidrug-resistant Enterobacterales isolated from hospital effluents and wastewater treatment plant. We present plasmid sequences of 21 multidrug resistant isolates of Enterobacterales belonging to Escherichia coli (n=10), Klebsiella pneumoniae (n=9), Klebsiella oxytoca (n=1), and Citrobacter freundii (n=1). The isolates originated from effluent collected from hospital sewer pipes and from a wastewater treatment plant (WWTP) in a southwestern Hungarian city. Isolation was carried out using eosin methylene blue agar supplemented with ceftriaxone and the isolates were identified with MALDI-TOF MS. Screening for multidrug resistance was conducted by determining susceptibility to four chemical classes namely, beta-lactams, aminoglycoside, fluoroquinolone, and sulfonamide. Plasmid DNA was isolated by alkaline lysis method using the Monarch plasmid DNA miniprep kit from freshly grown pure colonies. Molecular typing and Illumina sequencing of plasmid DNA of multiresistant strains were performed. After the assembly of contigs, genes localized on plasmid sequences were determined and functionally annotated. These reconstructed plasmid sequences supplemented with gene functional annotations were deposited in the Mendeley data. Using these datasets different plasmid incompatibility groups were identified. These conjugative plasmids appear to play a key role in the transmission of multiple resistance genes in enteric bacteria via wastewater. The presented data may provide useful insight on the correlations between environmental antibiotic contamination and the development of bacterial resistance, which poses a serious public health threat. | 2022 | 36426060 |
| 846 | 17 | 0.9995 | Pan-Resistome Characterization of Uropathogenic Escherichia coli and Klebsiella pneumoniae Strains Circulating in Uganda and Kenya, Isolated from 2017-2018. Urinary tract infection (UTI) develops after a pathogen adheres to the inner lining of the urinary tract. Cases of UTIs are predominantly caused by several Gram-negative bacteria and account for high morbidity in the clinical and community settings. Of greater concern are the strains carrying antimicrobial resistance (AMR)-conferring genes. The gravity of a UTI is also determined by a spectrum of other virulence factors. This study represents a pilot project to investigate the burden of AMR among uropathogens in East Africa. We examined bacterial samples isolated in 2017-2018 from in- and out-patients in Kenya (KY) and Uganda (UG) that presented with clinical symptoms of UTI. We reconstructed the evolutionary history of the strains, investigated their population structure, and performed comparative analysis their pangenome contents. We found 55 Escherichia coli and 19 Klebsiella pneumoniae strains confirmed uropathogenic following screening for the prevalence of UTI virulence genes including fimH, iutA, feoA/B/C, mrkD, and foc. We identified 18 different sequence types in E. coli population while all K. pneumoniae strains belong to ST11. The most prevalent E. coli sequence types were ST131 (26%), ST335/1193 (10%), and ST10 (6%). Diverse plasmid types were observed in both collections such as Incompatibility (IncF/IncH/IncQ1/IncX4) and Col groups. Pangenome analysis of each set revealed a total of 2862 and 3464 genes comprised the core genome of E. coli and K. pneumoniae population, respectively. Among these are acquired AMR determinants including fluoroquinolone resistance-conferring genes aac(3)-Ib-cr and other significant genes: aad, tet, sul1, sul2, and cat, which are associated with aminoglycoside, tetracycline, sulfonamide, and chloramphenicol resistance, respectively. Accessory genomes of both species collections were detected several β-lactamase genes, bla(CTX-M), bla(TEM) and bla(OXA,) or bla(NDM). Overall, 93% are multi-drug resistant in the E. coli collection while 100% of the K. pneumoniae strains contained genes that are associated with resistance to three or more antibiotic classes. Our findings illustrate the abundant acquired resistome and virulome repertoire in uropathogenic E. coli and K. pneumoniae, which are mainly disseminated via clonal and horizontal transfer, circulating in the East African region. We further demonstrate here that routine genomic surveillance is necessary for high-resolution bacterial epidemiology of these important AMR pathogens. | 2021 | 34943759 |
| 1732 | 18 | 0.9995 | High Carriage Rate of the Multiple Resistant Plasmids Harboring Quinolone Resistance Genes in Enterobacter spp. Isolated from Healthy Individuals. Antimicrobial-resistant bacteria causing intractable and even fatal infections are a major health concern. Resistant bacteria residing in the intestinal tract of healthy individuals present a silent threat because of frequent transmission via conjugation and transposition. Plasmids harboring quinolone resistance genes are increasingly detected in clinical isolates worldwide. Here, we investigated the molecular epidemiology of plasmid-mediated quinolone resistance (PMQR) in Gram-negative bacteria from healthy service trade workers. From 157 rectal swab samples, 125 ciprofloxacin-resistant strains, including 112 Escherichia coli, 10 Klebsiella pneumoniae, two Proteus mirabilis, and one Citrobacter braakii, were isolated. Multiplex PCR screening identified 39 strains harboring the PMQR genes (including 17 qnr,19 aac(6')-Ib-cr, and 22 oqxA/oqxB). The genome and plasmid sequences of 39 and 31 strains, respectively, were obtained by short- and long-read sequencing. PMQR genes mainly resided in the IncFIB, IncFII, and IncR plasmids, and coexisted with 3-11 other resistance genes. The high PMQR gene carriage rate among Gram-negative bacteria isolated from healthy individuals suggests the high-frequency transmission of these genes via plasmids, along with other resistance genes. Thus, healthy individuals may spread antibiotic-resistant bacterial, highlighting the need for improved monitoring and control of the spread of antibiotic-resistant bacteria and genes in healthy individuals. | 2021 | 35052892 |
| 1650 | 19 | 0.9995 | Multidrug-Resistant Salmonella enterica 4,[5],12:i:- Sequence Type 34, New South Wales, Australia, 2016-2017. Multidrug- and colistin-resistant Salmonella enterica serotype 4,[5],12:i:- sequence type 34 is present in Europe and Asia. Using genomic surveillance, we determined that this sequence type is also endemic to Australia. Our findings highlight the public health benefits of genome sequencing-guided surveillance for monitoring the spread of multidrug-resistant mobile genes and isolates. | 2018 | 29553318 |