# | Rank | Similarity | Title + Abs. | Year | PMID |
|---|---|---|---|---|---|
| 0 | 1 | 2 | 3 | 4 | 5 |
| 902 | 0 | 1.0000 | Occurrence of IMP-8, IMP-10, and IMP-13 metallo-β-lactamases located on class 1 integrons and other extended-spectrum β-lactamases in bacterial isolates from Tunisian rivers. BACKGROUND: Antibiotic-resistant bacteria have been surveyed widely in water bodies, but few studies have determined the diversity of antibiotic-resistant bacteria in river waters. This study was undertaken to investigate the origin of resistance among polluted river bacterial isolates in Tunisia. METHODS: In this study 128 isolates resistant to β-lactam antibiotics were obtained from 2 polluted rivers in the north of Tunisia. Isolates were identified using Phoenix phenotyping criteria. The occurrence of bla(TEM), bla(SHV), bla(CTX-M), bla(CMY), bla(VIM), and bla(IMP) was studied by polymerase chain reaction (PCR) amplification and sequencing, and the genetic relatedness of the 16 IMP-producing Klebsiella pneumoniae isolates was analyzed by comparison of XbaI pulsed-field gel electrophoresis (PFGE) profiles. RESULTS: Using Phoenix phenotyping criteria, diverse genera of bacteria were identified with different rates of prevalence and with different minimum inhibitory concentrations against different antibiotics. The occurrence of bla(TEM), bla(SHV), bla(CTXM), bla(CMY), bla(VIM), and bla(IMP) genes was confirmed. The DNA sequences upstream and downstream of bla(IMP) genes were determined, revealing that all IMP-encoding genes constituted the first cassette of class 1 integrons, followed by aacA gene cassettes encoding aminoglycoside resistance. Comparison of PFGE profiles showed that only 2 of the isolates were clonal, the other 14 displaying unique profiles. The bla(CTX-M) gene was the most dominant of the extended-spectrum β-lactamase (ESBL) genes, while the bla(TEM) gene was the second-most dominant. CONCLUSION: The discovery of highly diverse ESBL-producing bacteria and metallo-β-lactamases, particularly bla(IMP), in polluted river water raises alarms with regard to the potential dissemination of antibiotic-resistant bacteria in communities through river environments. | 2013 | 22992193 |
| 903 | 1 | 0.9999 | Carbapenemase and ESBL genes with class 1 integron among fermenting and nonfermenting bacteria isolated from water sources from India. The present study was aimed to detect the carbapenemase, extended-spectrum β-lactamase (ESBL), and intI1 gene of class 1 integron among fermenting (n = 61) and nonfermenting (n = 10) bacterial isolates recovered from water samples (n = 128). Isolates were identified by 16S rRNA sequencing. These isolates showed reduced-susceptibility to third-generation cephalosporins and carbapenems. The isolates varied in number and size of plasmids (2 kb to >20 kb). Plasmid DNA screening showed 5·6, 7, 11·2 and 26·7% prevalence of bla(KPC) , bla(NDM) , bla(SHV) and bla(TEM) genes respectively. Diverse bla(NDM) (bla(NDM-1) and bla(NDM-4) ) and bla(SHV) subtypes (bla(SHV-2) and bla(SHV-11) ) were recorded, unlike the single allelic bla(KPC) (bla(KPC-2) ) and bla(TEM) (bla(TEM-1) ) gene. Of the total 27 bla-gene-producing bacterial isolates, seven isolates co-harboured the carbapenemase genes (bla(NDM) or bla(KPC) or the both) along with the ESBL genes (bla(SHV) or bla(TEM) ). The intI1 gene of class 1 integron was detected among 12 (44·4%) of ESBL- and/or carbapenemase-harbouring isolates. Gene transferability was seen among four of the 10 Enterobacteriaceae donors. Carbapenemases and ESBLs with class 1 integron among aquatic environmental isolates raise the serious issue of the biosecurity and health of the ecosystem. SIGNIFICANCE AND IMPACT OF THE STUDY: Anthropologically affected and polluted environment harbours the resistance threats, where a diverse bacterial species maintain, develop and exchange genetic determinants that constitute a risk to human and ecological health. The antimicrobial resistance (AMR) in Enterobacteriaceae and non-Enterobacteriaceae bacteria caused the failure of the therapy of last resort (carbapenems) and thus lead to life-threatening infections affecting public health. Surveillance and monitoring of AMR could be important for epidemiological, diagnostic testing and control of pathogens. This is a point-prevalence study reporting the comparative occurrence and co-occurrence of carbapenemase and extended-spectrum β-lactamase genes among fermenting and nonfermenting bacteria isolated from the aquatic environment in India. | 2020 | 31587338 |
| 1025 | 2 | 0.9999 | Detection of Extended Spectrum Beta-Lactamases Resistance Genes among Bacteria Isolated from Selected Drinking Water Distribution Channels in Southwestern Nigeria. Extended Spectrum Beta-Lactamases (ESBL) provide high level resistance to beta-lactam antibiotics among bacteria. In this study, previously described multidrug resistant bacteria from raw, treated, and municipal taps of DWDS from selected dams in southwestern Nigeria were assessed for the presence of ESBL resistance genes which include bla TEM, bla SHV, and bla CTX by PCR amplification. A total of 164 bacteria spread across treated (33), raw (66), and municipal taps (68), belonging to α-Proteobacteria, β-Proteobacteria, γ-Proteobacteria, Flavobacteriia, Bacilli, and Actinobacteria group, were selected for this study. Among these bacteria, the most commonly observed resistance was for ampicillin and amoxicillin/clavulanic acid (61 isolates). Sixty-one isolates carried at least one of the targeted ESBL genes with bla TEM being the most abundant (50/61) and bla CTX being detected least (3/61). Klebsiella was the most frequently identified genus (18.03%) to harbour ESBL gene followed by Proteus (14.75%). Moreover, combinations of two ESBL genes, bla SHV + bla TEM or bla CTX + bla TEM, were observed in 11 and 1 isolate, respectively. In conclusion, classic bla TEM ESBL gene was present in multiple bacterial strains that were isolated from DWDS sources in Nigeria. These environments may serve as foci exchange of genetic traits in a diversity of Gram-negative bacteria. | 2016 | 27563674 |
| 1039 | 3 | 0.9999 | Genetic Investigation of Beta-Lactam Associated Antibiotic Resistance Among Escherichia Coli Strains Isolated from Water Sources. BACKGROUND: Antimicrobial resistance is an important factor threatening human health. It is widely accepted that antibiotic resistant bacteria such as Escherichia coli (E. coli) released from humans and animals into the water sources, can introduce their resistance genes into the natural bacterial community. OBJECTIVE: The aim of this study was to investigate the prevalence of bla(TEM), bla(CTX), bla(SHV), bla(OXA) and bla(VEB) associated-antibiotic resistance among E. coli bacteria isolated from different water resources in Iran. METHODS: The study contained all E. coli strains segregated from different surface water sources. The Kirby-Bauer method and combined discs method was determined in this study for testing antimicrobial susceptibility and strains that produced Extended-Spectrum Beta Lactamases (ESBL), respectively. DNA extraction kit was applied for genomic and plasmid DNA derivation. Finally the frequency of resistant genes including bla(TEM), bla(CTX), bla(SHV), bla(OXA) and bla(VEB) in ESBL producing isolates were studied by PCR. RESULTS: One hundred E. coli strains were isolated and entered in the study. The highest antibiotic resistance was observed on clindamycin (96%). Moreover, 38.5% isolates were ESBL producers. The frequency of different ESBLs genes were 37%, 27%, 27%, and 25% for bla(TEM), bla(CTX), bla(SHV), and bla(OXA) , respectively. The bla(VEB) wasn't found in any isolates. CONCLUSION: The study revealed a high prevalence of CTX-M, TEM, SHV and OXA genes among E. coli strains in surface water resources. In conclusion, these results raised a concern regarding the presence and distribution of these threatening factors in surface water sources and its subsequent outcomes. | 2017 | 29151997 |
| 1047 | 4 | 0.9999 | Biofilm formation and antibiotic resistance profiles of water-borne pathogens. Water sources (surface water, drinking water, rivers, and ponds) are significant reservoirs for transmitting antibiotic-resistant bacteria. In addition, these waters are an important public health problem because they are suitable environments for transferring antibiotic resistance genes between bacterial species. Our study aimed to assess the prevalence of Extended-spectrum beta-lactamase (ESBL) producing isolates in water samples, the susceptibility of the isolates to the specified antibiotics, the determination of biofilm ability, antibiotic resistance genes, and the molecular typing of the isolates. For this purpose, Polymerase chain reaction (PCR) and Matrix-assisted laser desorption ionization-time of flight (MALDI-TOF) analyses were used. Out of 70 isolates, 15 (21%) were ESBL producing, and sent for the MALDI-TOF analysis, where Escherichia coli, Acinetobacter calcoaceticus, Enterobacter bugandensis, Acinetobacter pittii, Pseudomonas aeruginosa, Acinetobacter junii, Pseudomonas oleovorans, and Enterobacter ludwigigii were identified. Moreover, colistin resistance genes (mcr 1/2/6, mcr 4, mcr 5, mcr 3/7, and mcr 8), ESBL-encoding genes (bla(SHV), bla(TEM), and bla(CTX-M)) and carbapenemase genes (bla(NDM), bla(OXA-48), and bla(KPC)) using molecular analysis (PCR) were confirmed. The colistin resistance gene was detected at 80% (12/15) in the isolates obtained. The distribution of these isolates according to resistance genes was found as mcr 1/2/6 4 (20%), mcr 3/7 3 (13%), and mcr 5 (40%). Additionally, the isolates harbored bla(SHV)(6.6%) and bla(TEM) (6.6%) genes. However, bla(NDM), bla(OXA-48), bla(KPC), and bla(CTX-M) genes were not detected in any isolates. According to the Congo red agar method, seven (46.6%) isolates showed negative biofilm ability, and eight (53.3%) showed moderate biofilm ability. However, the microplate method detected weak biofilm in 53.3% of the isolates. In conclusion, this study provides evidence for the existence of multidrug-resistant bacteria that co-exist with mcr and ESBL genes in water sources. These bacteria can migrate to other environments and pose increasing threats to public health. | 2023 | 37004897 |
| 1038 | 5 | 0.9999 | Isolation of Extended Spectrum β-lactamase (ESBL) Producing Bacteria from Urban Surface Waters in Malaysia. BACKGROUND: This was a preliminary study to test for the presence of multiple antibiotic-resistant extended spectrum β-lactamase (ESBL) producing bacteria in Malaysian urban surface waters. Although the literature review revealed several published papers on clinical ESBL isolates in Malaysia, none were found on ESBL isolates obtained from local surface waters. METHODS: Isolated bacterial species were tested for resistance to cefotaxime, amoxicillin/clavulanate and aztreonam, and susceptibility to imipenem and meropenem using antibiotic susceptibility testing (AST) by disc diffusion. This served as a screening step to detect bacteria that could be potential ESBL species. 16S ribose ribonucleic acid (rRNA) polymerase chain reaction (PCR) testing with two clusters of bla (β-lactamase) gene primers was used to test for the bla genes CTX-M (Groups 1, 2, 9), OXA-1, SHV and TEM. RESULTS: A total of 19 isolates were found, possessing at least one of the bla genes tested for. There was a relatively high occurrence of CTX-M genes (84.2%) among these, followed by TEM genes (47.4%). The isolates were identified as Enterobacteriaceae (89.5%), predominantly Escherichia coli and Klebsiella pneumoniae. CONCLUSION: There appears to be a high occurrence of ESBL-bacteria in local surface waters, among these being opportunistic pathogens. The persistence and spread of these species in the environment poses a threat to exposed human populations. | 2013 | 23966820 |
| 1079 | 6 | 0.9999 | CTX-M-15-producing Escherichia coli clone B2-O25b-ST131 and Klebsiella spp. isolates in municipal wastewater treatment plant effluents. OBJECTIVES: The global occurrence of antibiotic resistance genes in bacteria in water environments is an increasing concern. Treated wastewater was sampled daily over a 45 day period from the outflow of a municipal wastewater treatment plant in Brno, Czech Republic, and examined for extended-spectrum β-lactamase (ESBL)-producing bacteria. METHODS: Water samples were cultivated on MacConkey agar with cefotaxime (2 mg/L) and individual colonies were examined for ESBL production. Phenotypic ESBL-positive bacteria identified as Escherichia coli or Klebsiella spp. were tested for the presence of antibiotic resistance genes, the virulence gene afa/dra and the bla(CTX-M) upstream region. Genetic relatedness was analysed by PFGE, multilocus sequence typing and plasmid analysis. RESULTS: A total of 68 ESBL-producing Enterobacteriaceae isolates were detected in 34 out of 45 wastewater samples. ESBL-producing isolates included 26 E. coli isolates, 4 Klebsiella pneumoniae isolates and 1 Klebsiella oxytoca isolate. The pandemic and multiresistant B2-O25b-ST131 clone was predominant, being detected among 19 E. coli isolates, and 17 of the B2-O25b-ST131 isolates were positive for the FIA replicon and the afa/dra operon and had an IS26 element flanking bla(CTX-M-15). Seventeen of the B2-O25b-ST131 isolates showed closely related PFGE profiles (defined by 84% band similarity) and belonged to identical clonal groups. CONCLUSIONS: The results highlight the inadequacy of the treatment process in removing multiresistant bacteria from municipal wastewater and point to a risk of transmission of clinically important multiresistant strains, such as the pandemic ST131 clone, to the environment. This is the first study demonstrating the pandemic ST131 clone in wastewater. | 2011 | 21954457 |
| 955 | 7 | 0.9999 | Occurrence and characteristics of extended-spectrum β-lactamase- and carbapenemase- producing bacteria from hospital effluents in Singapore. One of the most important resistance mechanisms in Gram-negative bacteria today is the production of enzymes causing resistance to cephalosporin and carbapenem antibiotics. The spread of extended-spectrum β-lactamases (ESBL)- and carbapenemase- producing Gram-negative bacteria is an emerging global public health problem. The aim of the present study was to (i) assess the prevalence of carbapenem-resistant bacteria (CRB) and ESBL-producing strains in sewage effluents from two major hospitals in Singapore, (ii) characterize the isolated strains and (iii) identify some of the ESBL and carbapenemase genes responsible for the resistance. CHROMagar ESBL and KPC plates were used to rapidly screen for ESBL-producing bacteria and those expressing reduced susceptibility to carbapenems, respectively. The abundance of ESBL-producers and CRB in hospital wastewater ranged between 10(3) and 10(6)CFU/mL. Out of the 66 isolates picked from ESBL and KPC plates, 95%, 82%, 82% and 76% were resistant to ceftriaxone, ceftazidime (3rd generation cephalosporin family), ertapenem and meropenem (carbapenem family), respectively. Among the resistant isolates, the most predominant taxa identified were Pseudomonas spp. (28.2%), Klebsiella spp. (28.2%), Enterobacter spp. (18.3%) and Citrobacter spp. (11.3%). PCR and sequencing analysis showed that the predominant β-lactamase genes were bla(SHV) (41.1%) followed by bla(NDM-1) (35.6%), bla(CTX) (35.6%) and bla(KPC) (28.8%). The results of this study show a high prevalence of bacteria resistant to modern extended-spectrum cephalosporins and carbapenems and the presence of ESBL- and carbapenemase producers in hospital effluents. These findings support the need to improve management of hospital wastewater in order to minimize the spread of antimicrobial resistant microorganisms from this source. | 2018 | 29751417 |
| 901 | 8 | 0.9999 | Emergence of plasmid-borne bla (oxa-181) gene in Ochrobactrum intermedium: first report from India. Wastewater has become a potential habitat for multi-drug-resistant bacteria. The present study aims to screen for the presence of carbapenem-resistant bacteria in sewage water samples collected from hospital and non-hospital sources. From a total of 19 sewage water samples collected, 100 carbapenem-resistant non-lactose-fermenting Gram-negative bacteria (CR-NF-GNB) were isolated using MacConkey agar cultured with 8 mg l(-1) of meropenem. On screening for beta-lactamase resistance genes (bla (NDM), bla (OXA-48-like), bla (IMP), bla (VIM) and bla (KPC)), one isolate, Ochrobactrum intermedium , was found to carry the plasmid-borne bla (OXA-48-like) gene. To the best of our knowledge, we provide the first report of the rare and emerging opportunistic pathogen Ochrobactrum intermedium encoding the OXA-181 gene in its plasmid. | 2019 | 32974517 |
| 954 | 9 | 0.9999 | Hospital effluents as a reservoir of beta-lactamase- and carbapenemase-producing enterobacteriaceae. The aim of this study was to determine the presence of beta-lactamase- (bla) producing Enterobacteriaceae in hospital effluent samples from two level II and III hospitals in Lima, Peru. The resistance profile of the isolated bacteria was identified and characterized using the MicroScan system for 18 antimicrobials, and the presence of extended spectrum beta-lactamases (ESBL) (blaCTX-M ,bla SHV bla TEM ,bla PER) and carbapenemases (bla KPC ,bla NDM ,bla VIM ,bla IMP) resistance genes was determined by conventional PCR. Thirty-two isolates were identified (20 Enterobacteriaceae and 12 gram-negative bacteria). All the isolated bacteria showed multidrug resistance. ESBL (bla TEM) and carbapenemase (blaKPC, blaIMP) genes were found in samples from the hospitals that we evaluated. The release of these microorganisms to public areas and the lack of treatment of the hospital effluents could be an important public health problem. | 2021 | 34468580 |
| 1037 | 10 | 0.9999 | Genetic Background of β-Lactamases in Enterobacteriaceae Isolates from Environmental Samples. The prevalence of β-lactamase-producing Enterobacteriaceae has increased worldwide. Although antibiotic-resistant bacteria are usually associated with hospitals, there are a growing number of reports of resistant bacteria in other environments. Concern about resistant microorganisms outside the hospital setting highlights the need to investigate mechanisms of antibiotic resistance in isolates collected from the environment. The present study evaluated the resistance mechanism to β-lactam antibiotics in 40 isolates from hospital sewage and surface water from the Dilúvio Stream, Porto Alegre City, Southern Brazil. The multiplex PCR technique was used to detect several resistance genes of β-lactamases: extended-spectrum β-lactamases (ESBLs), carbapenemases, and β-lactamase AmpC. After genes, detection amplicons were sequenced to confirm their identification. The clonal relationship was established by DNA macrorestriction using the XbaI enzyme, followed by pulsed-field gel electrophoresis (PFGE). The results indicated that resistance genes were present in 85% of the isolates. The most prevalent genes encoded narrow-spectrum β-lactamase, such as TEM-1 and SHV-1 with 70% of the strains, followed by carbapenemase KPC and GES (45%), ESBL types SHV-5 and CTX-M-8 (27.5%), and AmpC (ACT-1/MIR-1) (2.5%). Twelve isolates contained only one resistance gene, 14 contained two, and eight isolates had three resistance genes. PFGE indicated a clonal relationship among K. pneumoniae isolates. It was not possible to establish a clonal relationship between Enterobacter sp. isolates. The results highlight the potential of these resistance genes to spread in the polluted environment and to present a health risk to communities. This report is the first description of these resistance genes present in environmental samples other than a hospital in the city of Porto Alegre/RS. | 2017 | 28378066 |
| 1026 | 11 | 0.9999 | Analysis of Wastewater Reveals the Spread of Diverse Extended-Spectrum β-Lactamase-Producing E. coli Strains in uMgungundlovu District, South Africa. Wastewater treatment plants (WWTPs) are major reservoirs of antibiotic-resistant bacteria (ARB), favouring antibiotic resistance genes (ARGs) interchange among bacteria and they can provide valuable information on ARB circulating in a community. This study characterised extended-spectrum beta-lactamase (ESBL)-producing Escherichia coli from the influent and effluent of four WWTPs in uMgungundlovu District, KwaZulu-Natal, South Africa. E. coli was enumerated using the membrane filtration method and confirmed using the API 20E test and real-time polymerase chain reaction. ESBL-producers were phenotypically identified by their susceptibility to the third-generation cephalosporins using the disc diffusion and the double-disc synergy methods against cefotaxime (30 µg) with and without 10 µg clavulanic acid. Genotypic verification was by PCR of the TEM, SHV, and CTX-M genes. The clonality of isolates was assessed by ERIC-PCR. The highest E. coli count ranged between 1.1 × 10(5) (influent) and 4.3 × 10(3) CFU/mL (effluent). Eighty pure isolates were randomly selected, ten from the influent and effluent of each of the four WWTP. ESBLs were phenotypically confirmed in 49% (n = 39) of the isolates, of which 77% (n = 30) were genotypically confirmed. Seventy-three percent of the total isolates were multidrug-resistant (MDR). Only two isolates were susceptible to all antibiotics. Overall, resistance to first and second-generation cephalosporins was higher than to third and fourth generation cephalosporins. Also, 15% of the isolates were resistant to carbapenems. The CTX-M-type ESBL (67%; n = 20) was the most common ESBL antibiotic resistance gene (ARG) followed by TEM (57%; n = 17) and SHV-types (27%; n = 8). Also, a substantial number of isolates simultaneously carried all three ESBL genes. ERIC-PCR revealed a high diversity of isolates. The diversity of the isolates observed in the influent samples suggest the potential circulation of different ESBL-producing strains within the studied district, requiring a more comprehensive epidemiological study to prevent the spread of ESBL-producing bacteria within impoverished communities. | 2021 | 34356780 |
| 2620 | 12 | 0.9998 | GES-5 among the β-lactamases detected in ubiquitous bacteria isolated from aquatic environment samples. In this study, we investigated the β-lactamase-encoding genes responsible for β-lactam resistance phenotypes detected among 56 Gram-negative isolates (Gamma- and Alpha-proteobacteria) recovered from wastewater, urban streams, and drinking water. The β-lactam resistance mechanisms detected in 36 isolates comprised the presence of class A (bla(TEM)(-1) , bla(SHV)(-1) , bla(SHV)(-11) , bla(GES)(-5) ), class B (ImiS, L1), class C (bla(CMY)(-2) , bla(CMY)(-34) , bla(CMY)(-65) , bla(CMY)(-89) , bla(CMY)(-90) , bla(ACC)(-5) , bla(ACT)(-13) ), and class D (blaOXA-309)β-lactamase-encoding genes, some variants described for the first time here. Notably, the results showed antimicrobial resistance genes related not only to commonly used antibiotics, but also to carbapenems, providing the first description of a GES-5-producing Enterobacteriaceae. The importance of ubiquitous bacteria thriving in aquatic environments as reservoirs or carriers of clinically relevant resistance determinants was confirmed, and the need to monitor water habitats as potential sources for the emergence and/or spread of antibiotic resistance in the environment was highlighted. | 2014 | 24267783 |
| 980 | 13 | 0.9998 | Phenotypic and Molecular Characterization of Extended-Spectrum β-Lactamase, Plasmid-Mediated- AmpC, and Carbapenemase-Producing Enterobacteriaceae Isolated from Companion and Production Animals in Brazil. The crisis of bacterial resistance is an emerging One Health challenge, driven by the overuse of antimicrobials in medical and agricultural settings. This study aimed to investigate extended-spectrum β-lactamase (ESBL), Ampicillinase (AmpC), and carbapenemase production, and the presence of genes encoding these enzymes in Escherichia coli, Klebsiella spp., and Proteus spp., major contributors to infections and resistance isolates from animals. From 2016 to 2021, 130 multidrug-resistant (MDR) or extensively drug-resistant (XDR) isolates were recovered from the secretions, excretions, and organs of companion and production animals with active infections. Antibacterial sensitivity tests, along with phenotypic and genotypic detection of resistance enzymes, were performed. To the best of our knowledge, this is the first study in Brazil to estimate the prevalence of XDR Enterobacteriales isolated from companion and production animals, which accounted for 13.8% of the strains. Statistically significant differences (P < 0.05) in resistant bacteria between different classes and within the same class of antibacterial bacteria were found. The statistical probability between genotypic detection of ESBL (OR = 3.1) and phenotypic tests for AmpC (OR = 2.3) was also established. Approximately 32.3%, 17.6%, and 16.8% of the strains had positive phenotypic tests for ESBL, AmpC, and carbapenemases, respectively. Genetic analysis revealed the presence of bla(CTX-M) (60.0%), bla(AmpC) (9.18%), bla(KPC-2) (0.76%), and bla(NDM) (1.52%). AmpC genes were identified in 8.46% of the samples, with bla(CMY) being the most frequent (6.92%), followed by bla(DHA) (0.77%), and bla(FOX) (0.77%). The sequenced amplicons were deposited in NCBI. This study reveals critical data on Enterobacteriaceae with antibacterial resistance genes isolated from animals and may pose a significant threat to One health. | 2025 | 39903315 |
| 1049 | 14 | 0.9998 | Multiple Antibiotic-Resistant, Extended Spectrum-β-Lactamase (ESBL)-Producing Enterobacteria in Fresh Seafood. Members of the family Enterobacteriaceae include several human pathogens that can be acquired through contaminated food and water. In this study, the incidence of extended spectrum β-lactamase (ESBL)-producing enterobacteria was investigated in fresh seafood sold in retail markets. The ESBL-positive phenotype was detected in 169 (78.60%) isolates, with Escherichia coli being the predominant species (53), followed by Klebsiella oxytoca (27), and K. pneumoniae (23). More than 90% of the isolates were resistant to third generation cephalosporins, cefotaxime, ceftazidime, and cefpodoxime. Sixty-five percent of the isolates were resistant to the monobactam drug aztreonam, 40.82% to ertapenem, and 31.36% to meropenem. Resistance to at least five antibiotics was observed in 38.46% of the isolates. Polymerase Chain Reaction (PCR) analysis of ESBL-encoding genes detected bla(CTX), bla(SHV), and bla(TEM) genes in 76.92%, 63.3%, and 44.37% of the isolates, respectively. Multiple ESBL genes were detected in majority of the isolates. The recently discovered New Delhi metallo-β-lactamase gene (bla(NDM-1)) was detected in two ESBL⁺ isolates. Our study shows that secondary contamination of fresh seafood with enteric bacteria resistant to multiple antibiotics may implicate seafood as a potential carrier of antibiotic resistant bacteria and emphasizes an urgent need to prevent environmental contamination and dissemination of such bacteria. | 2017 | 28867789 |
| 900 | 15 | 0.9998 | Presence of OXA-23-producing isolates of Acinetobacter baumannii in wastewater from hospitals in southern Brazil. The aim of the study was to evaluate the dissemination of multiresistant isolates of Acinetobacter baumannii carrying resistance genes, by samples of wastewater from hospitals in Porto Alegre, Rio Grande do Sul, Brazil. We obtained 303 bacterial isolates from the wastewater of three hospitals in Porto Alegre, Rio Grande do Sul. For each isolate, we determined the profile of susceptibility to antimicrobials and the presence of the genes bla(OXA-23), bla(OXA-24), bla(OXA-51), bla(OXA-58), bla(SPM-1), bla(IMP), and bla(VIM.) The bla(OXA-51) gene was found in 56% of the isolates, indicating the presence of A. baumannii in this environment. Of these, three multiresistant isolates were positive for the bla(OXA-23) gene, in wastewater from two of the hospitals. The results obtained in this study indicate that isolates of A. baumannii which are multiresistant and carry resistance genes such as bla(OXA-51) and bla(OXA-23) are being released into the environment in the wastewater from the hospitals analyzed. Multiresistant Acinetobacter junii, the newly emerging pathogen, were also found among the multiresistant isolates. Hospital wastewater may be crucial to the development and dispersal of multiresistant bacteria, making waterbodies reservoirs of bacterial resistance. | 2011 | 21254809 |
| 1073 | 16 | 0.9998 | Occurrence of Extended Spectrum Cephalosporin-, Carbapenem- and Colistin-Resistant Gram-Negative Bacteria in Fresh Vegetables, an Increasing Human Health Concern in Algeria. The aim of this study was to screen for extended spectrum cephalosporin-, carbapenem- and colistin-resistant Gram-negative bacteria in fresh vegetables in Batna, Algeria. A total of 400 samples of fresh vegetables were collected from different retail stores. Samples were immediately subjected to selective isolation, then the representative colonies were identified using matrix-assisted laser desorption ionisation time-of-flight mass spectrometry (MALDI-TOF-MS). Phenotypic and genotypic analyses were carried out in terms of species identification and relative antibiotic resistance. Transferability of the carbapenemase and mcr-bearing plasmids was verified by conjugation. The clonal relationships of carbapenemase and mcr-positive Escherichia coli isolates were studied by multi-locus sequence typing (MLST). Sixty-seven isolates were characterised and were mostly isolated from green leafy vegetables, where the dominant species identified included Citrobacter freundii, Klebsiella pneumoniae, Enterobacter cloacae, Stenotrophomona maltophilia, E. coli and Citrobacter braakii. PCR and sequencing results showed that E. coli was the bacterial species presenting the highest antibiotic resistance level in parallel to bla(TEM) (n = 16) and bla(CTX-M-15) (n = 11), which were the most detected genes. Moreover, five isolates carried carbapenemase genes, including the bla(OXA-48) and/or bla(VIM-4) genes. The mcr-1 gene was detected in two E. coli isolates. MLST analysis revealed three different E. coli sequence types: ST101 (n = 1), ST216 (n = 1) and ST2298 (n = 1). Conjugation assays confirmed the transferability of the bla(OXA-48) and mcr-1 genes. In this study we report, for the first time, the detection of the bla(OXA-48) gene in E. coli and C. braakii isolates and the bla(VIM-4) gene in vegetables. To the best of our knowledge, this is the first report on the detection of mcr-1 genes from vegetables in Algeria. | 2022 | 35892378 |
| 1017 | 17 | 0.9998 | Evaluation of canine raw food products for the presence of extended-spectrum beta-lactamase- and carbapenemase-producing bacteria of the order Enterobacterales. OBJECTIVE: To assess the potential contamination of commercial raw dog food products with bacteria of the Enterobacterales order that produce extended spectrum beta-lactamase (ESBL) and carbapenemase enzymes, determine risk factors for contamination, and understand isolate genetic diversity. SAMPLES: A total of 200 canine raw food products. METHODS: Products were cultured on selective chromogenic agar following enrichment steps. Whole-genome sequencing was performed for isolates that were confirmed to produce an ESBL. Isolates were characterized by antimicrobial resistance genes, and multilocus sequences typing, and compared to other isolates in the NCBI database for clonality. Preservation method and protein sources were assessed as potential risk factors for contamination with ESBL and carbapenemase-producing bacteria of the Enterobacterales order. RESULTS: No carbapenemase-producing Enterobacterales (CPE) were identified, but ESBL-producing Enterobacterales bacteria were isolated from 20/200 products (10.0%; 95% CI, 7.3 to 16.5%), all of which were frozen. Pork-derived protein source products were 8.1 times (P = .001; 95% CI, 2.53 to 26.2) more likely to carry ESBL-producing Enterobacterales bacteria than other protein sources. WGS analysis confirmed the presence of ESBL genes in a total of 25 distinct isolates (19 Escherichia coli, 5 Klebsiella pneumoniae, and 1 Citrobacter braakii). Genes encoding CTX-M type ESBL enzymes were the most common (24/25 isolates, 96.0%) with blaCTX-M-27 being the most common allele (8/25, 32.0%). CLINICAL RELEVANCE: Frozen, raw food products may serve as a route of transmission of ESBL-producing Enterobacterales bacteria to companion animals. Veterinarians should advise owners about the risks of raw food diets, including potential exposure to antimicrobial-resistant bacteria. | 2022 | 35895774 |
| 1053 | 18 | 0.9998 | Antimicrobial Resistance and Extended-Spectrum Beta-Lactamase Genes in Enterobacterales, Pseudomonas and Acinetobacter Isolates from the Uterus of Healthy Mares. Antibiotic-resistant bacteria are a growing concern for human and animal health. The objective of this study was to determine the antimicrobial resistance and extended-spectrum beta-lactamase genes in Enterobacterales, Pseudomonas spp. and Acinetobacter spp. isolates from the uterus of healthy mares. For this purpose, 21 mares were swabbed for samples, which were later seeded on blood agar and MacConkey agar. The isolates were identified using MALDI-TOF and the antimicrobial susceptibility test was performed using the Kirby-Bauer technique. To characterize the resistance genes, a polymerase chain reaction (PCR) scheme was performed. Of the isolates identified as Gram-negative, 68.8% were Enterobacterales, represented by E. coli, Enterobacter cloacae, Citrobacter spp., and Klebsiella pneumoniae; 28.1% belonged to the genus Acinetobacter spp.; and 3.1% to Pseudomonas aeruginosa. A 9.3% of the isolates were multidrug-resistant (MDR), presenting resistance to antibiotics from three different classes, while 18.8% presented resistance to two or more classes of different antibiotics. The diversity of three genes that code for ESBL (bla(TEM), bla(CTX-M) and bla(SHV)) was detected in 12.5% of the strains. The most frequent was bla(SHV), while bla(TEM) and bla(CTX-M) were present in Citrobacter spp. and Klebsiella pneumoniae. These results are an alarm call for veterinarians and their environment and suggest taking measures to prevent the spread of these microorganisms. | 2023 | 37764953 |
| 2621 | 19 | 0.9998 | Extended Spectrum Beta-Lactamase (ESBL)-producing bacteria isolated from hospital wastewaters, rivers and aquaculture sources in Nigeria. Untreated wastewater is a risk factor for the spread of antibiotic resistance in the environment. However, little is known about the contribution of untreated wastewater to the burden of antibiotic resistance in the Nigerian environment. In this study, a total of 143 ceftazidime-/cefpodoxime-resistant bacteria isolated from untreated wastewater and untreated wastewater-contaminated surface and groundwater in Nigeria were screened for extended-spectrum β-lactamase (ESBL) genes, integrons and integron gene cassettes by PCR. The genetic environment of bla (CTX-M-15) was mapped by PCR and potentially conjugative plasmids were detected among the isolates by degenerate primer MOB typing (DPMT). ESBL production was confirmed in 114 (79.7%) isolates and ESBL genes (bla (SHV), bla (CTX-M-15) and bla (TEM)) were detected in 85 (74.6%) ESBL-producing isolates. bla (CTX-M-15) was associated with ISEcp1 and with orf477 in 12 isolates and with ISEcp1, IS26 and orf477 in six others. To the best of our knowledge, this is the first report of bla (CTX-M-15) in hand-dug wells and borehole serving as sources of drinking water and a first report of the genetic environment of bla (CTX-M-15) in environmental bacteria from Nigeria. The results of this study confirm untreated wastewater as an important medium for the spread of ESBL-producing bacteria within the Nigerian environment. Hence, the widespread practice of discharging untreated wastewater into the aquatic ecosystem in Nigeria is a serious risk to public health. | 2018 | 29139076 |