# | Rank | Similarity | Title + Abs. | Year | PMID |
|---|---|---|---|---|---|
| 0 | 1 | 2 | 3 | 4 | 5 |
| 955 | 0 | 1.0000 | 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 |
| 980 | 1 | 0.9999 | 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 |
| 954 | 2 | 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 |
| 903 | 3 | 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 |
| 993 | 4 | 0.9999 | Multidrug-resistant Enterobacteriaceae colonising the gut of adult rural population in South India. BACKGROUND: Multidrug-resistant (MDR) colonisers act as a reservoir for transmission of antibiotic resistance and are a source of infection. Exposure to antibiotics by the commensal flora renders them resistant. Antibiotic consumption and hospitalisation are two major factors influencing this. We studied, antibiotic-resistant bacteria colonising rural adult population who had restricted access to health care and presumably had low consumption of antibiotics. AIM: Detection of multidrug resistance genes of extended spectrum β-lactamase (ESBL-CTX-M), AmpC β-Lactamase (CIT), Klebsiella pneumoniae carbapenemase (KPC) and New Delhi Metallo β-lactamase (NDM) in Enterobacteriaceae colonising the gut of adult population in a South Indian rural community. METHODOLOGY: Faecal samples of 154 healthy volunteers were screened for Enterobacteriaceae resistant to commonly used antibiotics by standard methods, followed by phenotypic detection of ESBL by double disk synergy method, AmpC by spot inoculation and carbapenemases by imipenem and ethylenediaminetetraacetic acid + imipenem combined E-test strips and modified Hodge test. Polymerase chain reaction was done to detect bla(CTX-M,)bla(CIT,)bla(KPC-1) and bla(NDM-1) genes coding for ESBL, AmpC, KPC and NDM, respectively. RESULTS: Colonisation rate of enteric bacteria with MDR genes in the community was 30.1%. However, phenotypically, only ESBL (3.2%) and NDM (0.65%) were detected. While the genes coding for ESBL, AmpC and NDM were detected in 35.6%, 17.8% and 4.4% of the MDR isolates, respectively. CONCLUSIONS: Carriage of MDR strains with a potential to express multidrug resistance poses a threat of dissemination in the community. Awareness for restricted use of antibiotics and proper sanitation can contain the spread of resistant bacteria. | 2018 | 30880694 |
| 994 | 5 | 0.9999 | Moroccan Hospital Cockroaches: Carriers of Multidrug-Resistant Gram-Negative Bacteria. Antimicrobial resistance in Gram-negative bacteria (GNB) is a growing global health concern, particularly in hospital environments, where cockroaches act as vectors for resistant strains. This study aimed to analyze antimicrobial resistance and biofilm formation in GNB isolated from cockroaches collected in the hospital environment. Cockroaches were collected, and bacterial isolation was performed from their gut contents and external surfaces. GNB strains were tested for antibiotic susceptibility using the disk diffusion method and examined for Extended-spectrum β-lactamases (ESBLs) and carbapenemases production. Molecular characterization of ESBLs and carbapenemases in GNB involved PCR amplification of antibiotic resistance genes, while biofilm formation was studied using a microplate assay. Seventy-five cockroaches were collected from which 165 GNB were isolated. The prevalence of ESBL-producing and carbapenemase-producing GNB was 6.7 and 1.8%, respectively. The predominant ESBL gene was bla(CTX-M-28), while bla(NDM-1) was the only carbapenemase gene detected. The qnrS1 gene was found in one NDM-1-producing Klebsiella pneumoniae and three ESBL-producing Escherichia coli. The qacΔE1 gene was detected in an NDM-1-producing Citrobacter freundii and a CTX-M-28-producing E. coli, whereas one NDM-1-producing Enterobacter cloacae carried both qacΔE1 and acrA genes. Strains harboring qacΔE1 and/or acrA genes exhibited biofilm-forming capabilities, with biofilm formation observed in 81.81% of ESBL-producing isolates and 100% of carbapenemase-producing isolates. The study underscores the role of cockroaches in carrying and disseminating ESBL- and carbapenemase-producing GNB in hospital settings. The coexistence of disinfectant resistance genes and antibiotic resistance suggests co-selection mechanisms, while biofilm formation enhances bacterial survival. These findings underline the urgent need for infection control strategies. | 2025 | 40095169 |
| 995 | 6 | 0.9999 | Genetic Characterization of Extended-Spectrum Beta-Lactamase (ESBL) and Metallo-Beta-Lactamase (MBL) Producing Klebsiella pneumoniae from Diabetic Foot Ulcer (DFU). BACKGROUND: Antibiotic resistance in common pathogenic bacteria is linked with the genetic makeup. The genetic basis of antibiotic resistance may vary in different species or pathophysiological conditions. OBJECTIVES: We studied the antibiotic resistance in Klebsiella pneumonia isolates from DFU in the western Indian population. We also studied the presence of ESBL and MBL mechanisms of antibiotic resistance along with the prevalence of the genes involved in ESBL (TEM (ESBL) , SHV (ESBL) , and CTX-M (ESBL) ) and MBL (NDM-1 (bla) , KPC (bla) , OXA-48 (bla) , and VIM (bla) ) production. RESULTS: A total of 161 K. pneumoniae isolates were analyzed; among which 50.93% were positive for ESBL and 45.96% were positive for MBL production. Most of the isolates were resistant to antibiotics used in the present study and partially resistant to Imipenem and Amikacin. There was no relation between the antibiotic resistance of the isolates and the production of ESBL or MBL mechanism of antibiotic resistance. Further, TEM (ESBL) was the most prevalent gene in K. pneumoniae isolates followed by CTX-M (ESBL) , NDM-1 (bla) , SHV (ESBL) , and KPC (bla) . VIM (bla) was the least prevalent gene found in K. pneumoniae isolates. There was no difference in the prevalence of the genes with respect to the presence or absence of ESBL and MBL mechanism of resistance. Further, there was no relation between the prevalence of the genes and antibiotic resistance in K. pneumoniae isolates. CONCLUSION: These results along with the literature review suggest that the prevalence of the genes involved in antibiotic resistance mechanisms are widespread in India and their distribution varies in different studies. | 2024 | 39346272 |
| 1038 | 7 | 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 |
| 1051 | 8 | 0.9999 | Multi-drug Resistance, β-Lactamases Production, and Coexistence of bla (NDM-1) and mcr-1 in Escherichia coli Clinical Isolates From a Referral Hospital in Kathmandu, Nepal. The ability of pathogenic Escherichia coli to produce carbapenemase enzymes is a characteristic that allows them to resist various antibiotics, including last-resort antibiotics like colistin and carbapenem. Our objectives were to identify rapidly developing antibiotic resistance (AR), assess β-lactamases production, and detect mcr-1 and bla (NDM-1) genes in the isolates. A prospective cross-sectional study was carried out in a referral hospital located in Kathmandu from November 2019 to December 2020 using standard laboratory and molecular protocols. Among 77 total E. coli isolates, 64 (83.1%) of them were categorized as MDR. Phenotypically 13 (20.3%) colistin-resistant, 30 (46.9%) ESBL and 8 (12.5%) AmpC producers, and 5 (7.8%) ESBL/AmpC co-producers were distributed among MDR-E. coli. Minimum inhibitory concentrations (MIC) against the majority of MDR isolates were exhibited at 1 g/L. Of these 77 E. coli isolates, 24 (31.2%) were carbapenem-resistant. Among these carbapenem-resistant bacteria, 11 (45.9%) isolates were reported to be colistin-resistant, while 15 (62.5%) and 2 (8.3%) were MBL and KPC producers, respectively. Out of 15 MBL producers, 6 (40%) harbored bla (NDM-1), and 8 (61.5%) out of 13 colistin-resistant pathogens possessed mcr-1. The resistance by colistin- and carbapenem were statistically associated (P < .001). However, only 2 (18.2%) of the co-resistant bacteria were found to have both genes. Our study revealed the highly prevalent MDR and the carbapenem-resistant E. coli and emphasized that the pathogens possess a wide range of capabilities to synthesize β-lactamases. These findings could assist to expand the understanding of AR in terms of enzyme production. | 2023 | 36741474 |
| 1047 | 9 | 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 |
| 979 | 10 | 0.9999 | Integrative phenotypic and genomic analysis of extended-spectrum Beta-lactamase (ESBL) and carbapenemase genes in Enterobacteriaceae and Pseudomonaceae strains isolated from animals in a Spanish Veterinary Teaching Hospital. Antimicrobial resistance (AMR) is a major global health threat, exacerbated by globalization which facilitates the spread of resistant bacteria. Addressing this issue requires a One Health perspective, involving humans, animals, and the environment. This study aims to compare the phenotypic resistance profiles of 69 clinical bacterial isolates (Enterobacteriaceae and Pseudomonaceae) from a Veterinary Teaching Hospital in Spain with their genotypic resistance profiles based on the presence of Extended-Spectrum Beta-Lactamases (ESBLs), AmpC and carbapenemases -enconding genes. For the genotypical analysis, whole genome sequencing (WGS) was used. Phenotypic characterization revealed that 37 isolates (53.6 %) grew on ESBL-selective medium. Phenotypic confirmatory tests showed that 12 strains (17.4 %) had some type of ESBL and 21 (30.4 %) could have an AmpC. Also, 24 isolates (34.8 %) grew in selective media for carbapenemases-producing bacteria, and 2 of these had a class A carbapenemase based on the KPC&MBL&OXA-48 disc kit. The genotypic analysis revealed 20 isolates (29 %) had bla(TEM), 8 (11.6 %) had bla(CTX-M) and 7 (10.1 %) bla(SHV). 27 (39.1 %) isolates had class C beta-lactamase genes. 35 isolates (50.7 %) had bla(OXA), class D beta-lactamase. 37 strains (53.6 %) had an Inc. plasmid replicon associated with the spread of AMR genes, including beta-lactamases and carbapenemases. This study emphasizes the value of combining phenotypic and genomic analyses to better understand and address antibiotic resistance, especially in veterinary contexts. Integrating these approaches enhances diagnostic accuracy by identifying strains with resistance genes that may not show phenotypically, helping clinicians in anticipating resistance under selective pressure. | 2025 | 39808975 |
| 1001 | 11 | 0.9999 | Isolation and Characterization of Environmental Extended Spectrum β-Lactamase-Producing Escherichia coli and Klebsiella pneumoniae from Ouagadougou, Burkina Faso. Antimicrobial resistance (AMR) is a global public health threat. Quality data are needed to address the rise of multidrug-resistant clones, particularly in sub-Saharan Africa. In this study, we analysed the prevalence, antimicrobial resistance profile, and presence of genes encoding extended-spectrum β-lactamase-producing Escherichia coli (ESBL-Ec) and Klebsiella pneumoniae (ESBL-Kp) in environmental samples from Ouagadougou, Burkina Faso. Of 264 samples collected, 95 (36%) and 74 (28%) contained ESBL-Kp and ESBL-Ec, respectively. ESBL-Kp was more prevalent in runoff water and in treated and untreated wastewater, while ESBL-Ec was more prevalent in manure. Interestingly, wastewater treatment did not significantly reduce the recovery of ESBL bacteria. As expected, resistance to third- and fourth-generation cephalosporins was predominant, and rare for second generation cefoxitin. Interestingly, all the isolates from treated wastewater were susceptible to ampicillin and piperacillin, while all the other clones were resistant to these antibiotics. Regarding the ESBL-encoding genes, the bla(CTX-M) family was the most abundant, with the bla(CTX-M1) subfamily being the most prevalent. Carriage of combinations of ESBL genes was common, with the majority of the isolates harbouring 2-4 different genes. This study highlights the need for active surveillance to manage the risk of exposure to ESBL bacteria in Burkina Faso. | 2024 | 38543091 |
| 1049 | 12 | 0.9999 | 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 |
| 902 | 13 | 0.9999 | 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 |
| 1039 | 14 | 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 |
| 953 | 15 | 0.9999 | Distribution of resistance genes encoding ESBLs in Enterobacteriaceae isolated from biological samples in health centers in Ouagadougou, Burkina Faso. OBJECTIVE: Resistance to antibiotics most especially third generation cephalosporins has assumed a worrisome dimension globally. Genes conferring these resistance which are mediated by enzymes known as extended spectrum beta-lactamases (ESBLs) are now wide spread among several Enterobacteriaceae species. However there is paucity of data regarding the distribution of these genes in Burkina Faso. Hence this prospective study aims to determine the prevalence and distribution of ESBL encoding genes in ESBL producing Enterobacteriaceae strains isolated from clinical samples of patients attending the three major hospitals in Ouagadougou Burkina Faso. RESULTS: ESBL-encoding genes were assayed in 187 ESBL producing Enterobacteriaceae strains. Among these isolates, the prevalence of ESBL-producing strains with blaTEM, blaSHV and blaCTX-M genes were 26.2% (49/187), 5.9% (11/187) and 40.1% (75/187) respectively. The association of ESBL encoding genes with health centers was statistically significant (p = 0.0209). Approximately 39.6% of E. coli harbored CTX-M and Klebsiella spp. 5.9%. This study demonstrates the dissemination of TEM, SHV and CTX-M genes in ESBL producing Enterobacteriaceae strains in Ouagadougou. Continuous spread of these bacteria poses great public health risk, thus increased surveillance and regulation of antibiotics use is imperative in Burkina Faso. | 2018 | 30005695 |
| 2126 | 16 | 0.9999 | Carbapenemase genes among multidrug resistant gram negative clinical isolates from a tertiary hospital in Mwanza, Tanzania. The burden of antimicrobial resistance (AMR) is rapidly growing across antibiotic classes, with increased detection of isolates resistant to carbapenems. Data on the prevalence of carbapenem resistance in developing countries is limited; therefore, in this study, we determined the prevalence of carbapenemase genes among multidrug resistant gram negative bacteria (MDR-GNB) isolated from clinical specimens in a tertiary hospital in Mwanza, Tanzania. A total of 227 MDR-GNB isolates were analyzed for carbapenem resistance genes. For each isolate, five different PCR assays were performed, allowing for the detection of the major carbapenemase genes, including those encoding the VIM-, IMP-, and NDM-type metallo-beta-lactamases, the class A KPC-type carbapenemases, and the class D OXA-48 enzyme. Of 227 isolates, 80 (35%) were positive for one or more carbapenemase gene. IMP-types were the most predominant gene followed by VIM, in 49 (21.59%) and 28 (12%) isolates, respectively. Carbapenemase genes were most detected in K. pneumoniae 24 (11%), followed by P. aeruginosa 23 (10%), and E. coli with 19 isolates (8%). We have demonstrated for the first time a high prevalence of MDR-GNB clinical isolates having carbapenem resistance genes in Tanzania. We recommend routine testing for carbapenem resistance among the MDR-GNB particularly in systemic infections. | 2014 | 24707481 |
| 901 | 17 | 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 |
| 998 | 18 | 0.9999 | Extended spectrum beta-lactamases among Gram-negative bacteria of nosocomial origin from an intensive care unit of a tertiary health facility in Tanzania. BACKGROUND: Resistance to third generation cephalosporins due to acquisition and expression of extended spectrum beta-lactamase (ESBL) enzymes among Gram-negative bacteria is on the increase. Presence of ESBL producing organisms has been reported to significantly affect the course and outcome of an infection. Therefore infections due to ESBL isolates continue to pose a challenge to infection management worldwide. The aim of this study was to determine the existence and to describe phenotypic and genotypic characteristics of ESBLs in an Intensive Care Unit (ICU) setting in Tanzania. METHODS: Between October 2002 and April 2003, clinical information and samples were collected from patients suspected to have nosocomial infections in an Intensive Care Unit of a tertiary hospital in Tanzania. The isolates were identified, tested for antimicrobial susceptibility and analysed for presence of ESBL genes. RESULTS: Thirty-nine Gram-negative bacteria were isolated from clinical samples of 39 patients. These isolates included 13 Escherichia coli, 12 Enterobacter spp, 5 Pseudomonas spp, 4 Proteus spp, 2 Klebsiella. pneumoniae, 2 Citrobacter freundii and 1 Chryseomonas luteola. Eleven (28.2%) of these isolates were ESBL producing. The ESBL genes characterised were SHV-12, SHV-28 and CTX-M-15. The ESBL producing isolates were more resistant to gentamicin and ciprofloxacin than non-ESBL producing isolates. CONCLUSION: This study shows the presence of ESBL genes among Gram-negative bacteria in the ICU setting in Tanzania. There is a need to institute strict hospital infection control policy and a regular surveillance of resistance to antimicrobial agents. | 2005 | 16225701 |
| 990 | 19 | 0.9999 | Resistance phenotype-genotype correlation and molecular epidemiology of Citrobacter, Enterobacter, Proteus, Providencia, Salmonella and Serratia that carry extended-spectrum β-lactamases with or without plasmid-mediated AmpC β-lactamase genes in Thailand. Extended-spectrum β-lactamases (ESBLs) and plasmid-mediated AmpC β-lactamases (pAmpCs) have been increasingly reported among less commonly encountered genera of Enterobacteriaceae. However, little is known regarding the genetic characteristics of resistance genes and epidemiology of these genera. Lack of accurate ESBL and pAmpC detection may adversely affect therapeutic outcomes. This study investigated resistance phenotype-genotype correlation and molecular epidemiology among six genera of Enterobacteriaceae (Citrobacter, Enterobacter, Proteus, Providencia, Salmonella and Serratia) that carried ESBL with or without pAmpC genes at a university hospital in Thailand. From a total of 562 isolates, 105 isolates (18.7%) had ESBL-positive phenotype whilst 140 isolates (24.9%) harboured one or more ESBL genes. CTX-M and TEM were common ESBL-related bla genes among these isolates. The sensitivity and specificity of ESBL phenotypic detection as opposed to ESBL gene detection were 70.7% and 98.6%, respectively. pAmpC genes were detected in 96 ESBL gene-carrying isolates (68.6%) and significantly caused false negative detection of ESBL. Molecular typing based on pulsed-field gel electrophoresis revealed several clones that may be endemic in this hospital. This study indicated a high prevalence of ESBLs and pAmpCs among less common members of the family Enterobacteriaceae in Thailand and these resistant bacteria need to be monitored. | 2011 | 20880563 |