# | Rank | Similarity | Title + Abs. | Year | PMID |
|---|---|---|---|---|---|
| 0 | 1 | 2 | 3 | 4 | 5 |
| 1067 | 0 | 0.9548 | Virulence and plasmidic resistance determinants of Escherichia coli isolated from municipal and hospital wastewater treatment plants. Escherichia coli is simultaneously an indicator of water contamination and a human pathogen. This study aimed to characterize the virulence and resistance of E. coli from municipal and hospital wastewater treatment plants (WWTPs) in central Portugal. From a total of 193 isolates showing reduced susceptibility to cefotaxime and/or nalidixic acid, 20 E. coli with genetically distinct fingerprint profiles were selected and characterized. Resistance to antimicrobials was determined using the disc diffusion method. Extended spectrum β-lactamase and plasmid-mediated quinolone resistance genes, phylogroups, pathogenicity islands (PAIs) and virulence genes were screened by polymerase chain reaction (PCR). CTX-M producers were typed by multilocus sequence typing. Resistance to beta-lactams was associated with the presence of bla(TEM), bla(SHV), bla(CTX-M-15) and bla(CTX-M-32). Plasmid-mediated quinolone resistance was associated with qnrA, qnrS and aac(6')-Ib-cr. Aminoglycoside resistance and multidrug-resistant phenotypes were also detected. PAI IV(536), PAI II(CFT073), PAI II(536) and PAI I(CFT073), and uropathogenic genes iutA, papAH and sfa/foc were detected. With regard to the clinical ST131 clone, it carried bla(CTX-M-15), blaTEM-type, qnrS and aac(6')-lb-cr; IncF and IncP plasmids, and virulence factors PAI IV(536), PAI I(CFT073), PAI II(CFT073), iutA, sfa/foc and papAH were identified in the effluent of a hospital plant. WWTPs contribute to the dissemination of virulent and resistant bacteria in water ecosystems, constituting an environmental and public health risk. | 2015 | 26042965 |
| 1235 | 1 | 0.9541 | Characterization of integrons and antimicrobial resistance genes in clinical isolates of Gram-negative bacteria from Palestinian hospitals. Sixty Gram-negative bacterial isolates were collected from Palestinian hospitals in 2006. Thirty-two (53.3%) isolates showed multidrug resistance phenotypes. PCR and DNA sequencing were used to characterize integrons and antimicrobial resistance genes. PCR screening showed that 19 (31.7%) and five (8.3%) isolates were positive for class 1 and class 2 integrons, respectively. DNA-sequencing results for the captured antimicrobial resistance gene cassettes within class 1 integrons identified the following genes: dihydrofolate reductases, dfrA1, dfrA5, dfrA7, dfrA12, dfrA17 and dfrA25; aminoglycoside adenyltransferases, aadA1, aadA2, aadA5, aadA12 and aadB; aminoglycoside acetyltransferase, aac(6')-Ib; and chloramphenicol resistance gene, cmlA1. ESBL were identified in 25 (41.7%) isolates. The identified ESBL were bla(CTX-M-15), bla(CTX-M-56), bla(OXA-1), bla(SHV-1), bla(SHV-12), bla(SHV-32) and bla(TEM-1) genes. Moreover, we characterized the plasmid-mediated quinolone resistance genes, aac(6')-Ib-cr and qnrB2, which were detected in seven (11.7%) and two (3.3%) isolates, respectively. In this study various types of antibiotic resistance genes have been identified in Gram-negative bacteria from Palestinian hospitals, many of which are reported in the Middle East area for the first time. | 2009 | 19903259 |
| 1451 | 2 | 0.9541 | Molecular Epidemiology of Extensively Drug-Resistant mcr Encoded Colistin-Resistant Bacterial Strains Co-Expressing Multifarious β-Lactamases. Plasmid-mediated colistin resistance (Col-R) conferred by mcr genes endangers the last therapeutic option for multifarious β-lactamase-producing bacteria. The current study aimed to explore the mcr gene molecular epidemiology in extensively drug-resistant (XDR) bacteria. Col-R gram-negative bacterial strains were screened using a minimum inhibitory concentration (MIC) breakpoint ≥4 µg/mL. Resistant isolates were examined for mcr variants, extended-spectrum β-lactamase, AmpC, and carbapenemase genes using polymerase chain reaction (PCR). The MIC breakpoints for mcr-positive strains were determined using broth microdilution and E-test strips. Overall, 19/718 (2.6%) gram-negative rods (GNRs) harboring mcr were identified, particularly in pus (p = 0.01) and tracheal secretions (p = 0.03). Molecular epidemiology data confirmed 18/19 (95%) mcr-1 and 1/19 (5%) mcr-2 genes. Integron detection revealed 15/17 (88%) Int-1 and 2/17 (12%) Int-2. Common co-expressing drug-resistant β-lactamase genes included 8/16 (50%) bla(CTM-1), 3/16 (19%) bla(CTM-15), 3/3 (100%) bla(CMY-2), 2/8 (25%) bla(NDM-1), and 2/8 (25%) bla(NDM-5). The MIC(50) and MIC(90) values (µg/mL) were as follows: Escherichia coli, 12 and 24; Klebsiella pneumoniae, 12 and 32; Acinetobacter baumannii, 8 and 12; and Pseudomonas aeruginosa, 32 and 64, respectively. Treatment of XDR strains has become challenging owing to the co-expression of mcr-1, mcr-2, multifarious β-lactamase genes, and integrons. | 2021 | 33923991 |
| 1218 | 3 | 0.9540 | Whole genome sequencing snapshot of multi-drug resistant Klebsiella pneumoniae strains from hospitals and receiving wastewater treatment plants in Southern Romania. We report on the genomic characterization of 47 multi-drug resistant, carbapenem resistant and ESBL-producing K. pneumoniae isolates from the influent (I) and effluent (E) of three wastewater treatment plants (WWTPs) and from Romanian hospital units which are discharging the wastewater in the sampled WWTPs. The K. pneumoniae whole genome sequences were analyzed for antibiotic resistance genes (ARGs), virulence genes and sequence types (STs) in order to compare their distribution in C, I and E samples. Both clinical and environmental samples harbored prevalent and widely distributed ESBL genes, i.e. blaSHV, blaOXA, blaTEM and blaCTX M. The most prevalent carbapenemase genes were blaNDM-1, blaOXA-48 and blaKPC-2. They were found in all types of isolates, while blaOXA-162, a rare blaOXA-48 variant, was found exclusively in water samples. A higher diversity of carbapenemases genes was seen in wastewater isolates. The aminoglycoside modifying enzymes (AME) genes found in all types of samples were aac(6'), ant(2'')Ia, aph(3'), aaD, aac(3) and aph(6). Quinolone resistance gene qnrS1 and the multi-drug resistance oqxA/B pump gene were found in all samples, while qnrD and qnrB were associated to aquatic isolates. The antiseptics resistance gene qacEdelta1 was found in all samples, while qacE was detected exclusively in the clinical ones. Trimethroprim-sulfamethoxazole (dfrA, sul1 and sul2), tetracyclines (tetA and tetD) and fosfomycin (fosA6, known to be located on a transpozon) resistance genes were found in all samples, while for choramphenicol and macrolides some ARGs were detected in all samples (catA1 and catB3 / mphA), while other (catA2, cmIA5 and aac(6')Ib / mphE and msrE) only in wastewater samples. The rifampin resistance genes arr2 and 3 (both carried by class I integrons) were detected only in water samples. The highly prevalent ARGs preferentially associating with aquatic versus clinical samples could ascribe potential markers for the aquatic (blaSHV-145, qacEdelta1, sul1, aadA1, aadA2) and clinical (blaOXA-1, blaSHV-106,blaTEM-150, aac(3)Iia, dfrA14, oqxA10; oqxB17,catB3, tetD) reservoirs of AR. Moreover, some ARGs (oqxA10; blaSHV-145; blaSHV-100, aac(6')Il, aph(3')VI, armA, arr2, cmlA5, blaCMY-4, mphE, msrE, oqxB13, blaOXA-10) showing decreased prevalence in influent versus effluent wastewater samples could be used as markers for the efficiency of the WWTPs in eliminating AR bacteria and ARGs. The highest number of virulence genes (75) was recorded for the I samples, while for E and C samples it was reduced to half. The most prevalent belong to three functional groups: adherence (fim genes), iron acquisition (ent, fep, fyu, irp and ybt genes) and the secretion system (omp genes). However, none of the genes associated with hypervirulent K. pneumoniae have been found. A total of 14 STs were identified. The most prevalent clones were ST101, ST219 in clinical samples and ST258, ST395 in aquatic isolates. These STs were also the most frequently associated with integrons. ST45 and ST485 were exclusively associated with I samples, ST11, ST35, ST364 with E and ST1564 with C samples. The less frequent ST17 and ST307 aquatic isolates harbored blaOXA-162, which was co-expressed in our strains with blaCTX-M-15 and blaOXA-1. | 2020 | 31999747 |
| 1215 | 4 | 0.9539 | The role of the plasmid-mediated fluoroquinolone resistance genes as resistance mechanisms in pediatric infections due to Enterobacterales. INTRODUCTION: Fluoroquinolones (FQs) are not commonly prescribed in children, yet the increasing incidence of multidrug-resistant (MDR) Enterobacterales (Ent) infections in this population often reveals FQ resistance. We sought to define the role of FQ resistance in the epidemiology of MDR Ent in children, with an overall goal to devise treatment and prevention strategies. METHODS: A case-control study of children (0-18 years) at three Chicago hospitals was performed. Cases had infections by FQ-susceptible, β-lactamase-producing (bla) Ent harboring a non- or low-level expression of PMFQR genes (PMFQS Ent). Controls had FQR infections due to bla Ent with expressed PMFQR genes (PMFQR Ent). We sought bla genes by PCR or DNA (BD Max Check-Points assay(®)) and PMFQR genes by PCR. We performed rep-PCR, MLST, and E. coli phylogenetic grouping. Whole genome sequencing was additionally performed on PMFQS Ent positive isolates. Demographics, comorbidities, and device, antibiotic, and healthcare exposures were evaluated. Predictors of infection were assessed. RESULTS: Of 170 β-lactamase-producing Ent isolates, 85 (50%) were FQS; 23 (27%) had PMFQR genes (PMFQS cases). Eighty-five (50%) were FQR; 53 (62%) had PMFQR genes (PMFQR controls). The median age for children with PMFQS Ent and PMFQR Ent was 4.3 and 6.2 years, respectively (p = NS). Of 23 PMFQS Ent, 56% were Klebsiella spp., and of 53 PMFQR Ent, 76% were E. coli. The most common bla and PMFQR genes detected in PMFQS Ent were bla (SHV ESBL) (44%) and oqxAB (57%), and the corresponding genes detected in PMFQR Ent were bla (CTX-M-1-group ESBL) (79%) and aac(6')-Ib-cr (83%). Whole genome sequencing of PMFQS Ent revealed the additional presence of mcr-9, a transferable polymyxin resistance gene, in 47% of isolates, along with multiple plasmids and mobile genetic elements propagating drug resistance. Multivariable regression analysis showed that children with PMFQS Ent infections were more likely to have hospital onset infection (OR 5.7, 95% CI 1.6-22) and isolates containing multiple bla genes (OR 3.8, 95% CI 1.1-14.5). The presence of invasive devices mediated the effects of healthcare setting in the final model. Differences in demographics, comorbidities, or antibiotic use were not found. CONCLUSIONS: Paradoxically, PMFQS Ent infections were often hospital onset and PMFQR Ent infections were community onset. PMFQS Ent commonly co-harbored multiple bla and PMFQR genes, and additional silent, yet transferrable antibiotic resistance genes such as mcr-9, affecting therapeutic options and suggesting the need to address infection prevention strategies to control spread. Control of PMFQS Ent infections will require validating community and healthcare-based sources and risk factors associated with acquisition. | 2023 | 37900312 |
| 1240 | 5 | 0.9537 | Prevalence and characterization of quinolone resistance and integrons in clinical Gram-negative isolates from Gaza strip, Palestine. BACKGROUND: Gram-negative bacteria with quinolone resistance and extended-spectrum beta-lactamases (ESBLs) present significant treatment challenges. This study evaluated the prevalence and characteristics of quinolone resistance in Gram-negative strains, investigating the relationship between plasmid-mediated quinolone resistance (PMQR), ESBLs, and integrons. METHODS AND RESULTS: We collected 146 Gram-negative isolates from patients in three Palestinian hospitals. For quinolone resistance isolates, the presence and characterization of PMQR, β-lactamase genes and integrons were studied by PCR and sequencing. Out of 146 clinical isolates, 64 (43.8%) were resistant to quinolones, with 62 (97%) being multidrug-resistant (MDR) and 33 (51.5%) ESBL-producers. PMQR-encoding genes were present in 45 (70.3%) isolates, including aac(6')-Ib-cr (26.6%), qnrA (18.8%), qnrS1 (20.8%), and qnrB (6.4%). Bla(CTX-M) genes were detected in 50% (32/64) of isolates, with bla(CTX-M-15) being the most common. Bla(TEM-1), bla(SHV-1) and bla(VIM) genes were found in 13, 6, and 4 isolates, respectively. Class I integrons were found in 31/64 (48%) of isolates, with 14 containing gene cassettes conferring resistance to trimethoprim (dhfr17, dfrA12, dfrA1) and aminoglycosides resistance genes (aadA1, aadA2, aadA5, and aadA6). CONCLUSIONS: This study found a high rate of quinolone resistance, ESBL and integrons in clinical Gram-negative isolates from our hospitals. Urgent measures are crucial, including implementing an antimicrobial resistance surveillance system, to control and continuously monitor the development of antimicrobial resistance. | 2024 | 39066817 |
| 1413 | 6 | 0.9537 | Occurrence of Carbapenemases, Extended-Spectrum Beta-Lactamases and AmpCs among Beta-Lactamase-Producing Gram-Negative Bacteria from Clinical Sources in Accra, Ghana. Beta-lactamase (β-lactamase)-producing Gram-negative bacteria (GNB) are of public health concern due to their resistance to routine antimicrobials. We investigated the antimicrobial resistance and occurrence of carbapenemases, extended-spectrum β-lactamases (ESBLs) and AmpCs among GNB from clinical sources. GNB were identified using matrix-assisted laser desorption/ionization time of flight-mass spectrometry (MALDITOF-MS). Antimicrobial susceptibility testing was performed via Kirby-Bauer disk diffusion and a microscan autoSCAN system. β-lactamase genes were determined via multiplex polymerase chain reactions. Of the 181 archived GNB analyzed, Escherichia coli and Klebsiella pneumoniae constituted 46% (n = 83) and 17% (n = 30), respectively. Resistance to ampicillin (51%), third-generation cephalosporins (21%), and ertapenem (21%) was observed among the isolates, with 44% being multi-drug resistant (MDR). β-lactamase genes such as AmpCs ((bla(FOX-M) (64%) and bla(DHA-M) and bla(EDC-M) (27%)), ESBLs ((bla(CTX-M) (81%), other β-lactamase genes bla(TEM) (73%) and bla(SHV) (27%)) and carbapenemase ((bla(OXA-)(48) (60%) and bla(NDM) and bla(KPC) (40%)) were also detected. One K. pneumoniae co-harbored AmpC (bla(FOX-M) and bla(EBC-M)) and carbapenemase (bla(KPC) and bla(OXA-)(48)) genes. bla(OXA-)(48) gene was detected in one carbapenem-resistant Acinetobacter baumannii. Overall, isolates were resistant to a wide range of antimicrobials including last-line treatment options. This underpins the need for continuous surveillance for effective management of infections caused by these pathogens in our settings. | 2023 | 37370334 |
| 1232 | 7 | 0.9537 | Monitoring of Non-β-Lactam Antibiotic Resistance-Associated Genes in ESBL Producing Enterobacterales Isolates. Genetic context of extended spectrum β-Lactamase (ESBL) producing Enterobacterales and its association with plasmid mediated quinolone resistance (PMQR), aminoglycoside modifying enzymes (AME) and Trimethoprim/Sulfamethoxazole (TMP-SMX) resistance is little known from North India. Therefore, the current study was aimed to investigate the frequency of Non-β-Lactam antibiotic resistance associated genes in extended spectrum β-Lactamase producing Enterobacterales. For this study, Non-Duplicate phenotypically confirmed ESBL producing Enterobacterales isolates (N = 186) were analyzed for ESBLs, PMQRs, AMEs and TMP-SMX resistance genes using polymerase chain reaction (PCR). PCR detected presence of PMQR genes in 81.29% (N = 139) of ESBL isolates (N = 171), AME genes in 60.82% and TMP-SMX resistance genes in 63.74% of the isolates. Molecular characterization of ESBL producing Enterobacterales showed 84.79% bla(TEM) followed by 73.68% bla(CTX-M), 43.86% bla(SHV), 19.88% bla(PER) and 9.94% bla(VEB), respectively. Analysis of PMQR genes revealed 77.7% aac(6')-lb-cr the most commonly detected gene followed by 67.63% oqxB, 62.59% oqxA, 43.17% qnrB, 19.42% qnrD, 18.7% qnrS, 9.35% qnrA, 3.6% qepA and 2.88% qnrC, respectively. Analysis of AMEs gene profile demonstrated 81.73% aac(6')-Ib, the most frequently encountered gene followed by 46.15% aph(3')-Ia, 44.23% ant(3")-Ia, respectively. A 100% prevalence of sul1, followed by dfrA (54.63%) and sul2 (15.74%) was observed. In summary, prevalence of ESBL-Producing genes (particularly bla(TEM) and bla(CTX-M)) along with PMQR, AMEs, and TMP-SMX resistant genes may potentially aid in the transfer of antimicrobial resistance among these strains. | 2020 | 33317078 |
| 1243 | 8 | 0.9533 | Population distribution of Beta-lactamase conferring resistance to third-generation cephalosporins in human clinical Enterobacteriaceae in the Netherlands. There is a global increase in infections caused by Enterobacteriaceae with plasmid-borne β-lactamases that confer resistance to third-generation cephalosporins. The epidemiology of these bacteria is not well understood, and was, therefore, investigated in a selection of 636 clinical Enterobacteriaceae with a minimal inhibitory concentration >1 mg/L for ceftazidime/ceftriaxone from a national survey (75% E. coli, 11% E. cloacae, 11% K. pneumoniae, 2% K. oxytoca, 2% P. mirabilis). Isolates were investigated for extended-spectrum β-lactamases (ESBLs) and ampC genes using microarray, PCR, gene sequencing and molecular straintyping (Diversilab and multi-locus sequence typing (MLST)). ESBL genes were demonstrated in 512 isolates (81%); of which 446 (87%) belonged to the CTX-M family. Among 314 randomly selected and sequenced isolates, bla(CTX-M-15) was most prevalent (n = 124, 39%), followed by bla(CTX-M-1) (n = 47, 15%), bla(CTX-M-14) (n = 15, 5%), bla(SHV-12) (n = 24, 8%) and bla(TEM-52) (n = 13, 4%). Among 181 isolates with MIC ≥16 mg/L for cefoxitin plasmid encoded AmpCs were detected in 32 and 27 were of the CMY-2 group. Among 102 E. coli isolates with MIC ≥16 mg/L for cefoxitin ampC promoter mutations were identified in 29 (28%). Based on Diversilab genotyping of 608 isolates (similarity cut-off >98%) discriminatory indices of bacteria with ESBL and/or ampC genes were 0.994, 0.985 and 0.994 for E. coli, K. pneumoniae and E. cloacae, respectively. Based on similarity cut-off >95% two large clusters of E. coli were apparent (of 43 and 30 isolates) and 21 of 21 that were typed by belonged to ST131 of which 13 contained bla(CTX-M-15). Our findings demonstrate that bla(CTX-M-15) is the most prevalent ESBL and we report a larger than previously reported prevalence of ampC genes among Enterobacteriaceae responsible for resistance to third-generation cephalosporins. | 2012 | 23284886 |
| 1068 | 9 | 0.9533 | Dissemination of IncF plasmids carrying beta-lactamase genes in Gram-negative bacteria from Nigerian hospitals. INTRODUCTION: Production of beta-lactamases is the predominant cause of resistance to beta-lactam antibiotics in Gram-negative bacteria. We investigated the diversity of plasmid-borne beta-lactamase genes and replicon type of the plasmids carrying the respective genes in Gram-negative bacteria recovered from clinical infection in Nigerian hospitals. METHODOLOGY: A total of 134 Gram-negative bacteria of 13 species were analyzed for antimicrobial susceptibility, phenotypic and genotypic detection of various beta-lactamases, and plasmid analysis, including replicon typing. RESULTS: Of the 134 isolates, 111 (82.8%) contained beta-lactamases, while 28 (20.9%) carried extended-spectrum beta-lactamases. PCR and sequencing identified TEM-1 in 109 isolates (81.3%), SHV-1 in 33 isolates (24.6%), OXA-1 in 15 isolates (11.2%) and CTX-M enzymes (24 CTX-M-15 and 1 CTX-M-3) in 25 isolates (18.7%). Multiplex PCR showed that 6 isolates carried plasmidic AmpCs (ACT-1, DHA-1 and CMY-2); these enzymes were detected only in isolates possessing CTX-M beta-lactamases. Of 13 (76.9%) representative plasmids investigated in detail, 9 (69.2%) were self-transferable when selected by a beta-lactam and the plasmids once transferred coded for beta-lactam resistance. Replicon typing indicated IncF as the common vector encoding for beta-lactamases. CONCLUSIONS: The study showed a diversity of beta-lactamase genes disseminated by conjugative IncF plasmids in Gram-negative bacteria; TEM-1, SHV-1, OXA-1, CTX-M-15, CTX-M-3 and plasmidic AmpC enzymes are in common circulation in Nigeria. | 2013 | 23669427 |
| 1412 | 10 | 0.9533 | A highly multiplexed melt-curve assay for detecting the most prevalent carbapenemase, ESBL, and AmpC genes. Resistance to third-generation cephalosporins and carbapenems in Gram-negative bacteria is chiefly mediated by beta-lactamases including extended-spectrum beta-lactamase (ESBL), AmpC, and carbapenemase enzymes. Routine phenotypic detection methods do not provide timely results, and there is a lack of comprehensive molecular panels covering all important markers. An ESBL/carbapenemase high-resolution melt analysis (HRM) assay (SHV, TEM, CTX-M ESBL families, and NDM, IMP, KPC, VIM and OXA-48-like carbapenemases) and an AmpC HRM assay (16S rDNA control, FOX, MOX, ACC, EBC, CIT, and DHA) were designed and evaluated on 111 Gram-negative isolates with mixed resistance patterns. The sensitivity for carbapenemase, ESBL, and AmpC genes was 96.7% (95% confidence interval [CI]: 82.8-99.9%), 93.6% (95% CI: 85.7-97.9%), and 93.8% (95% CI: 82.8-98.7%), respectively, with a specificity of 100% (95% CI: 95.6-100%), 93.9% (95% CI: 79.8-99.3%), and 93.7% (95% CI: 84.5-98.2%). The HRM assays enable the simultaneous detection of the 14 most important ESBL, carbapenemase, and AmpC genes and could be used as a molecular surveillance tool or to hasten detection of antimicrobial resistance for treatment management. | 2020 | 32521424 |
| 1092 | 11 | 0.9532 | High qnrS retention of ESBL-producing and mcr-harbouring colistin-resistant Escherichia coli in Vietnamese food products. Plasmid-mediated antibiotic-resistant bacteria's transmission is fatal and a major threat to public health. This study aimed to clarify the presence of plasmid-mediated quinolone resistance(PMQR)genes in extended-spectrum β-lactamase(ESBL)-producing or/and mcr-harbouring colistin(COL)-resistant Escherichia coli(ESBL-COL-EC)isolates from Vietnamese and Japanese chicken meat. Resistance towards ciprofloxacin(CIP)was examined in 308 ESBL-COL-EC isolates; CIP-resistant ESBL-COL-EC isolates were examined for the PMQR gene. Approximately, 71.1% and 38.1% of ESBL-COL-EC and ESBLproducing E. coli isolates from Vietnamese and Japanese chicken meat were CIP-resistant, respectively. Multiplex PCR led PMQR detection showed that 35.2% of CIP-resistant ESBL-COL-EC isolates from Vietnamese food contained PMQR gene, whereas CIP-resistant ESBL-COL-EC isolates from Japanese chicken meat did not. Conjugation assays showed that the transmission of qnrS gene carried by E. coli to Salmonella. In conclusion, ESBL-COL-EC isolates from Vietnamese food are associated with a high frequency of fluoroquinolone resistance and a high distribution of the qnrS gene. | 2024 | 39343582 |
| 830 | 12 | 0.9531 | Detection and characterisation of 16S rRNA methyltransferase-producing Pseudomonas aeruginosa from the UK and Republic of Ireland from 2003-2015. 16S rRNA methyltransferase (16S RMTase) genes confer high-level aminoglycoside resistance, reducing treatment options for multidrug-resistant Gram-negative bacteria. Pseudomonas aeruginosa isolates (n = 221) exhibiting high-level pan-aminoglycoside resistance (amikacin, gentamicin and tobramycin MICs ≥64, ≥32 and ≥32 mg/L, respectively) were screened for 16S RMTase genes to determine their occurrence among isolates submitted to a national reference laboratory from December 2003 to December 2015. 16S RMTase genes were identified using two multiplex PCRs, and whole-genome sequencing (WGS) was used to identify other antibiotic resistance genes, sequence types (STs) and the genetic environment of 16S RMTase genes. 16S RMTase genes were found in 8.6% (19/221) of isolates, with rmtB4 (47.4%; 9/19) being most common, followed by rmtD3 (21.1%; 4/19), rmtF2 (15.8%; 3/19) and single isolates harbouring rmtB1, rmtC and rmtD1. Carbapenemase genes were found in 89.5% (17/19) of 16S RMTase-positive isolates, with bla(VIM) (52.9%; 9/17) being most common. 16S RMTase genes were found in 'high-risk' clones known to harbour carbapenemase genes (ST233, ST277, ST357, ST654 and ST773). Analysis of the genetic environment of 16S RMTase genes identified that IS6100 was genetically linked to rmtB1; IS91 to rmtB4, rmtC or rmtD3; ISCR14 to rmtD1; and rmtF2 was linked to Tn3, IS91 or Tn1721. Although 16S RMTase genes explained only 8.6% of pan-aminoglycoside resistance in the P. aeruginosa isolates studied, the association of 16S RMTase genes with carbapenemase-producers and 'high-risk' clones highlights that continued surveillance is required to monitor spread as well as the importance of suppressing the emergence of dually-resistant clones in hospital settings. | 2022 | 35176475 |
| 1230 | 13 | 0.9531 | Lentic and effluent water of Delhi-NCR: a reservoir of multidrug-resistant bacteria harbouring blaCTX-M, blaTEM and blaSHV type ESBL genes. Antimicrobial resistance is not restricted to clinics but also spreading fast in the aquatic environment. This study focused on the prevalence and diversity of extended-spectrum β-lactamase (ESBL) genes among bacteria from lentic and effluent water in Delhi-NCR, India. Phenotypic screening of 436 morphologically distinct bacterial isolates collected from diverse sites revealed that 106 (∼24%) isolates were ESBL positive. Antibiotic profiling showed that 42, 60, 78 and 59% ESBL producing isolates collected from Ghazipur slaughterhouse, Lodhi garden pond, Hauz Khas lake and Jasola wastewater treatment plant, respectively, were multidrug-resistant (MDR). The multiple antibiotic resistance (MAR) index varied from 0.20 to 0.32 among selected locations. The prevalence of ESBL gene variants blaSHV, blaTEM and blaCTX-M were found to be 17.64, 35.29 and 64%, respectively. Furthermore, the analysis of obtained gene sequences showed three variants of blaCTX-M (15, 152 and 205) and two variants of blaTEM (TEM-1 and TEM-116) among ESBL producers. The co-existence of 2-3 gene variants was recorded among 48% ESBL positive isolates. New reports from this study include the blaCTX-M gene in Acinetobacter lwoffii, Enterobacter ludwigii, Exiguobacterium mexicanum and Aeromonas caviae. Furthermore, the identification of blaTEM and blaSHV in an environmental isolate of A. caviae is a new report from India. | 2021 | 34371496 |
| 1387 | 14 | 0.9531 | Whole-Genome Characterisation of ESBL-Producing E. coli Isolated from Drinking Water and Dog Faeces from Rural Andean Households in Peru. E. coli that produce extended-spectrum β-lactamases (ESBLs) are major multidrug-resistant bacteria. In Peru, only a few reports have characterised the whole genome of ESBL enterobacteria. We aimed to confirm the identity and antimicrobial resistance (AMR) profile of two ESBL isolates from dog faeces and drinking water of rural Andean households and determine serotype, phylogroup, sequence type (ST)/clonal complex (CC), pathogenicity, virulence genes, ESBL genes, and their plasmids. To confirm the identity and AMR profiles, we used the VITEK(®)2 system. Whole-genome sequencing (WGS) and bioinformatics analysis were performed subsequently. Both isolates were identified as E. coli, with serotypes -:H46 and O9:H10, phylogroups E and A, and ST/CC 5259/- and 227/10, respectively. The isolates were ESBL-producing, carbapenem-resistant, and not harbouring carbapenemase-encoding genes. Isolate 1143 ST5259 harboured the astA gene, encoding the EAST(1) heat-stable toxin. Both genomes carried ESBL genes (bla(EC-15), bla(CTX-M-8), and bla(CTX-M-55)). Nine plasmids were detected, namely IncR, IncFIC(FII), IncI, IncFIB(AP001918), Col(pHAD28), IncFII, IncFII(pHN7A8), IncI1, and IncFIB(AP001918). Finding these potentially pathogenic bacteria is worrisome given their sources and highlights the importance of One-Health research efforts in remote Andean communities. | 2022 | 35625336 |
| 1391 | 15 | 0.9528 | Faecal carriage of extended-spectrum β-lactamase-producing and AmpC β-lactamase-producing bacteria among Danish army recruits. During May and June 2008, 84 Danish army recruits were tested for faecal carriage of extended-spectrum β-lactamase (ESBL)-producing and AmpC β-lactamase-producing bacteria. Three ESBL-producing (CTX-M-14a) Escherichia coli isolates, two AmpC-producing (CMY-2) E. coli isolates and one AmpC-producing (CMY-34) Citrobacter freundii isolate were detected. Two of the CTX-M-14a E. coli isolates had similar pulsed-field gel electrophoresis and multilocus sequence typing profiles, indicating the same origin or transmission between the two army recruits. The bla(CTX-M-14a) genes were transferable to an E. coli recipient. These commensal bacteria therefore constitute a reservoir of resistance genes that can be transferred to other pathogenic bacteria in the intestine. | 2011 | 20718802 |
| 1231 | 16 | 0.9528 | Prevalence and Molecular Characterization of Plasmid-mediated Extended-Spectrum β-Lactamase Genes (balaTEM, blaCTX and blASHV) Among Urinary Escherichia coli Clinical Isolates in Mashhad, Iran. OBJECTIVES: Extended-spectrum beta-lactamase (ESBL) producing bacteria have an important role in nosocomial infections. Due to the limited availability of information about the molecular epidemiology of ESBL producing bacteria in Mashhad, we decided to investigate about TEM, CTX and SHV ESBLs among urinary Escherichia coli isolates in Mashhad, a city in northeast Iran. MATERIALS AND METHODS: One hundred and eleven clinical isolates of E. coli were diagnosed from hospitalized patients in 2009. After performing antibiogram and phenotypic confirmation test, polymerase chain reaction (PCR) was performed by blaTEM, blaSHV and blaCTX primers and restriction digestion was carried out using PstI and TaqI (Fermentas-Lithuania) for confirmation. RESULTS: ESBL producers of E. coli isolates were 33.3%. Among 37 ESBL-producing isolates, 35 (94.6%), 21 (56.8%) and 5 (13.5%) were shown to have blaCTX, blaTEM and blaSHV, genes respectively. Co-resistance to non-beta lactam antibiotics was observed more with ESBL producers (P < 0.05). CONCLUSION: The results showed that the studied ESBL genes are found with high prevalence and among them blaCTX is more widespread in urine E. coli isolates in Mashhad. | 2012 | 23493415 |
| 1241 | 17 | 0.9528 | Spectrum of Bacterial Colonization in Patients Hospitalized for Treatment of Multidrug-Resistant Tuberculosis. This study investigated the bacterial colonization in patients admitted for treatment of drug-resistant tuberculosis in a specialized TB hospital. Identification and antimicrobial susceptibility testing of bacterial isolates (n = 62) from nasal, groin, and rectal swabs [patient cohort (n = 37)] were determined by the VITEK-MS system. Resistance gene analysis was by PCR and DNA sequencing. Molecular typing of Klebsiella pneumoniae isolates was by Multilocus Sequencing Typing (MLST). Patients (n = 13/37; 35%) were colonized by multidrug-resistant (MDR) bacteria (ESBL and MRSA) on admission. Of the 24 patients who were not colonized by MDR bacteria on admission, 46% (17/37) became colonized by MDR bacteria within 1 month of admission, mostly with ESBL-producing Enterobacteriales and resistance to aminoglycosides and fluoroquinolones. ESBL Escherichia coli (41/62; 66%) and K. pneumoniae (14/62; 23%) predominated. Genes encoding for ESBLs (bla(CTX-M-14), bla(CTX-M-15), bla(SHV-28), bla(OXA-1), and bla(OXY-2)) and plasmid-mediated quinolone resistant genes (qnrB1, qnrB4, and qnrB10) were detected. MLST revealed genetic diversity among the K. pneumoniae isolates from hospitalized patients. This study provides insight into bacterial pathogen colonization in hospitalized TB patients with the first occurrence of the qnrB4 and qnrB10 genes and co-expression of genes: qnrB4+aac(6')-lb-cr, qnrB10+aac(6')-lb-cr, qnrB4+qnrS1, and qnrB10+qnrS1 in fluoroquinolone-resistant E. coli isolates within South Africa. However, the source and colonization routes of these isolates could not be determined. | 2021 | 33074767 |
| 1088 | 18 | 0.9528 | Detection and Molecular Characterization of Escherichia coli Strains Producers of Extended-Spectrum and CMY-2 Type Beta-Lactamases, Isolated from Turtles in Mexico. Multidrug-resistant bacteria are a growing problem in different environments and hosts, but scarce information exists about their prevalence in reptiles. The aim of this study was to analyze the resistance mechanisms, molecular typing, and plasmid content of cefotaxime-resistant (CTX(R)) Escherichia coli isolates recovered from cloacal samples of 71 turtles sheltered in a herpetarium in Mexico. CTX(R)-E. coli were recovered in 11 of 71 samples (15.5%), and one isolate/sample was characterized. Extended-spectrum β-lactamase (ESBL)-producing E. coli isolates were detected in four samples (5.6%): two strains carried the blaCTX-M-2 gene (phylogroup D and ST2732) and two contained the blaCTX-M-15 gene (phylogroup B1 and lineages ST58 and ST156). The blaCMY-2 gene was detected by PCR in E. coli isolates of eight samples (9.8%) (one of them also carried blaCTX-M-2); these isolates were distributed into phylogroups A (n = 1), B1 (n = 6), and D (n = 1) and typed as ST155, ST156, ST2329, and ST2732. Plasmid-mediated quinolone resistance (PMQR) genes were detected in five isolates [aac(6')Ib-cr, qnrA, qnrB19, and oqxB]. From three to five replicon plasmids were detected among the strains, being IncFIB, IncI1, IncFrep, and IncK the most prevalent. ESBL or pAmpC genes were transferred by conjugation in four strains, and the blaCTX-M-15 and blaCMY-2 genes were localized in IncFIB or IncI1 plasmids by Southern blot hybridization assays. Class 1 and/or class 2 integrons were detected in eight strains with six different structures of gene cassette arrays. Nine pulsed-field gel electrophoresis patterns were found among the 11 studied strains. To our knowledge, this is the first detection of ESBL, CMY-2, PMQR, and mobile determinants of antimicrobial resistance in E. coli of turtle origin, highlighting the potential dissemination of multidrug-resistant bacteria from these animals to other environments and hosts, including humans. | 2016 | 27482752 |
| 1404 | 19 | 0.9528 | Evaluation of a DNA microarray for rapid detection of the most prevalent extended-spectrum β-lactamases, plasmid-mediated cephalosporinases and carbapenemases in Enterobacteriaceae, Pseudomonas and Acinetobacter. The dissemination of Gram-negative bacteria (GNB) producing extended-spectrum β-lactamases (ESBLs), plasmid-encoded cephalosporinases (pAmpCs) and carbapenemases is a matter of great clinical concern. In this study, we evaluated a new low-density DNA array 'Check-MDR CT103 XL' (Check-Points, Wageningen, The Netherlands) that identifies the most clinically relevant β-lactamase genes of ESBLs (blaTEM, blaSHV, blaCTX-M, blaBEL, blaPER, blaGES and blaVEB), pAmpCs (blaCMY-2-like, blaDHA, blaFOX, blaACC-1, blaACT/MIR and blaCMY-1-like/MOX) and carbapenemases (blaKPC, blaOXA-48, blaVIM, blaIMP, blaNDM, blaGIM, blaSPM and blaOXA-23, -24 and -58) in cultured bacteria. In total, 223 GNB isolates with well-characterised resistance mechanisms to β-lactams were analysed. A specificity and sensitivity of 100% were recorded for most bla genes, with a slightly lower signal observed for blaIMP. The Check-MDR CT103 XL array proved highly accurate for the identification of epidemiologically relevant ESBL, pAmpC and carbapenemase genes harboured in Enterobacteriaceae, Pseudomonas and Acinetobacter spp. The Check-MDR CT103 XL assay is a significant improvement compared with Check-MDR CT103 and it highlights the ability of this array to evolve rapidly to adjust to the current needs for the detection of resistance mechanisms to β-lactam agents. | 2016 | 27374747 |