# | Rank | Similarity | Title + Abs. | Year | PMID |
|---|---|---|---|---|---|
| 0 | 1 | 2 | 3 | 4 | 5 |
| 1118 | 0 | 1.0000 | Detection and characterization of extended-spectrum β-lactamases (blaCTX-M-1 and blaSHV ) producing Escherichia coli, Salmonella spp. and Klebsiella pneumoniae isolated from humans in Mizoram. AIM: The present study was conducted to isolate and characterize the extended spectrum β-lactamases (ESBLs) producing enteric bacteria in human beings in Mizoram, India. MATERIALS AND METHODS: Fecal samples were collected from human beings with or without the history of diarrhea from different hospitals of Mizoram. Samples were processed for isolation and identification of Escherichia coli, Salmonella and Klebsiella pneumoniae. All the isolates were subjected to antibiotic sensitivity assays. Phenotypically, ESBLs production ability was determined by double discs synergy test (DDST) method. ESBLs producing isolates were subjected to polymerase chain reaction (PCR) for detection of ESBLs genes. Plasmids were cured by acridine orange. Transfer of resistance from a donor to recipient strains was done by in vitro horizontal method. RESULTS: A total of 414 enteric bacteria were isolated from 180 fecal samples (113 were from diarrheic patients and 67 were from non-diarrheic patients), of which 333 (80.44%), 52 (12.56%), and 29 (7.00%) were E. coli, K. pneumoniae and Salmonella spp., respectively. Double discs synergy test (DDST) exhibited 72 (21.62%) E. coli, 12 (23.08%) K. pneumoniae and 4 (13.79%) Salmonella spp. were ESBLs producers. Altogether, 24 (13.04%) isolates were found to be positive for at least one resistance genes under this study. A total of 36 (8.70%) E. coli, 4 (0.97%) K. pneumoniae and 2 (0.48%) Salmonella spp. were found to be positive for blaCTX-M-1 gene by PCR. Similarly, 5 (1.21%) E. coli and 4 (0.97%) K. pneumoniae isolates were found to be positive for blaSHV gene. A total of 3 (0.72%) K. pneumoniae isolates were recorded as positive for both blaCTX-M-1 and blaSHV genes. All the isolates were carrying plasmids ranging between 0.9 kb and ~30 kb. The resistance plasmid could not be transferred to a recipient by in vitro horizontal gene transfer method. CONCLUSION: ESBLs producing enteric bacteria are circulating in human population in North Eastern Region of India. Indiscriminate use of antibiotics should be avoided to control the menace of multidrug resistance bacteria in the environment, animals, and human beings. | 2015 | 27047141 |
| 1117 | 1 | 0.9999 | CTX-M-type ESBL-mediated resistance to third-generation cephalosporins and conjugative transfer of resistance in Gram-negative bacteria isolated from hospitals in Tamil Nadu, India. Clinical pathogens, especially Gram-negative bacteria developing resistance to third-generation cephalosporins, are making clinical outcomes more complicated and serious. This study was undertaken to evaluate the distribution of CTX-M-type extended-spectrum β-lactamases (ESBLs) in Tamil Nadu, India. For this study, clinical samples were collected from five different hospitals located in Tamil Nadu and the ESBL-producing Gram-negative isolates were characterized. MIC was performed using cefotaxime and ceftazidime. The bla (ESBL)-producing genes were screened using multiplex PCR for the genes, CTX-M group-1, -2, -8, -9, -26. The conjugation studies were performed using Escherichia coli AB1157 as a recipient for the isolates harbouring plasmid-borne resistance following broth-mating experiment. In total, 1500 samples were collected and 599 Gram-negative bacteria were isolated that included E. coli (n=233), Klebsiella pneumoniae (n=182), Pseudomonas aeruginosa (n=79), Citrobacter spp. (n=30), Proteus mirabilis (n=28), Salmonella spp. (n=21), Acinetobacter baumannii (n=12), Serratia spp. (n=6), Shigella spp. (n=4), Morganella morganii (n=3) and Providencia spp. (n=1). MIC results showed that 358 isolates were resistant to cefotaxime and ceftazidime. Further, ESBL gene-amplification results showed that 19 isolates had CTX-M group-1 gene including E. coli (n=16), K. pneumoniae (n=2) and P. aeruginosa (n=1) whereas one M. morganii isolate had CTX-M group-9, which was plasmid-borne. Through conjugation studies, 12/20 isolates were found to be involved in the transformation of its plasmid-borne resistance gene. Our study highlighted the importance of horizontal gene transfer in the dissemination of plasmid-borne bla (CTX-M-type) resistance genes among the clinical isolates. | 2021 | 34151148 |
| 1124 | 2 | 0.9999 | Molecular Identification of Extended-Spectrum β-lactamase and Integron Genes in Klebsiella Pneumonia. INTRODUCTION: Infections caused by Gram negative bacteria, producing extended-spectrum β-lactamase, including Klebsiella pneumoniae are increasing all over the world with high morbidity and mortality. The aim of the present study was determined antimicrobial profile susceptibility and the prevalence of antibiotic resistance genes by multiplex PCR. METHODS: In the present study, we obtained one-hundred isolates of K. pneumoniae from different clinical samples. The antibiotic susceptibility testing was done in thirteen antibiotic and, therefore, M-PCRs were conducted using the DNA amplification for detection of ESBLs (blaTEM, blaCTX-M, blaSHV) and int (I, II, III) genes. RESULTS: The results of resistance to amoxicillin/clavulanate, ciprofloxacin, amikacin, trimethoprim-sulfamethoxazole, cefotaxime, ampicillin, aztreonam, imipenem, gentamicin, ceftazidime, Cefepime, ceftriaxone and levofloxacin were obtained 37%, 37%, 93%, 84%, 52%, 87%, 59%, 8%, 24%, 67%, 52%, 43% and 26%, respectively. The frequency of the extended-spectrum β-lactamase K. pneumoniae was obtained 37%. The prevalence of resistance genes of ESBLs in the M-PCR method showed that the blaTEM, blaCTX and blaSHV were 38%, 24% and 19%, respectively, however, only 8 (8%) out of 100 isolates were found to have positive outcomes for the existence of class 1 integrons and there were no detected class 2 or class 3 integrons. CONCLUSIONS: Our results recommend the likely co-carriage of some ESBLs genes and antibiotic resistance integrons on the same plasmids harboring the MDR genes. | 2016 | 27935927 |
| 1121 | 3 | 0.9999 | Occurrence of the genes encoding carbapenemases, ESBLs and class 1 integron-integrase among fermenting and non-fermenting bacteria from retail goat meat. The present study was planned to detect the genes encoding carbapenemases, ESBLs and class 1 integron-integrase among bacteria obtained from retail goat meat. Fermenting and non-fermenting bacterial isolates (n = 57), recovered from 61 goat meat samples, were identified by 16S rRNA gene sequencing. Antimicrobial susceptibility of isolates was tested by the broth dilution method using ceftazidime, cefotaxime, meropenem and imipenem. Plasmids were isolated and tested for their physical characters. Plasmids were subjected to screening of carbapenemase, ESBL and intI1 gene. Conjugation assay was performed using bla(NDM) -positive isolates as the donor, and Escherichia coli HB101 as the recipient. Isolates showed the high rates of resistance to ceftazidime (77·2%), cefotaxime (70·2%), meropenem (22·8%) and imipenem (17·5%). They showed variability in number and size (~1 to >20 kb) of plasmids. Among all, 1, 4, 13 and 31 isolates showed the bla(KPC) , bla(NDM) , bla(SHV) and bla(TEM) genes, respectively. The bla(KPC-2) gene was observed in one E. coli isolate. The bla(NDM-1) gene was detected in Stenotrophomonas maltophilia (n = 2), Acinetobacter baumannii (n = 1) and Ochrobactrum anthropi (n = 1) isolates. These isolates co-harboured the bla(TEM) and bla(SHV) genes. The intI1 gene was detected in 22 (38·6%) isolates, and 16 of these isolates showed the carbapenemase and/or ESBL genes. The conjugative movement of bla(NDM) gene could not be proved after three repetitive mating experiments. The presence of genes encoding carbapenemases and ESBLs in bacteria from goat meat poses public health risks. | 2020 | 32767781 |
| 1046 | 4 | 0.9999 | Extended-spectrum β-lactamases producing multidrug resistance Escherichia coli, Salmonella and Klebsiella pneumoniae in pig population of Assam and Meghalaya, India. AIM: The present study was conducted to record the prevalence of extended spectrum β-lactamases (ESBLs) producing Escherichia coli, Salmonella spp., and Klebsiella pneumoniae from pig population of Assam and Meghalaya and to record the ability of the resistant bacteria to transfer the resistance genes horizontally. MATERIALS AND METHODS: Fecal samples (n=228), collected from pigs of Assam (n=99) and Meghalaya (n=129), were processed for isolation and identification of E. coli and Salmonella spp. All the isolates were tested for ESBLs production by double disc synergy test (DDST) followed by screening for ESBLs producing genes (bla(TEM), bla(SHV), bla(CTX-M), and bla(CMY)) by polymerase chain reaction (PCR). Possible transfer of resistance encoding genes between enteric bacterial species was carried out by in vitro and in vivo horizontal gene transfer (HGT) method. RESULTS: A total of 897 enteric bacteria (867 E. coli and 30 Salmonella) were isolated and identified. Altogether 25.41% isolates were confirmed as ESBL producers by DDST method. Majority of the isolates were E. coli followed by Salmonella. By PCR, 9.03% isolates were found positive for at least one of the target resistance genes. bla(SHV) was absent in all the isolates. bla(CMY) was the most prevalent gene. All the E. coli isolates from Assam were negative for bla(TEM). A total of 2.76% isolates were positive for bla(TEM) + bla(CMY). On the other hand, 0.67% isolates were positive for bla(CTX-M) + bla(CMY) genes. Only 0.33% isolates carried all the three genes. Altogether, 4.68% bacteria carried the resistance encoding genes in their plasmids. bla(TEM) gene could be successfully transferred from Salmonella (donor) to E. coli (recipient) by in vitro (5.5-5.7×10(-5)) and in vivo (6.5×10(-5) to 8.8×10(-4)) methods. In vivo method was more effective than in vitro in the transfer of resistance genes. CONCLUSION: The pig population of Assam and Meghalaya are carrying multidrug resistance and ESBLs producing E. coli and Salmonella. The isolates are also capable to transfer their resistance trait to other bacterial species by HGT. The present finding could be considered as a serious public health concern as similar trait can also be transmitted to the human commensal bacteria as well as pathogens. | 2018 | 30034183 |
| 1045 | 5 | 0.9999 | ESBL-Producing Enterobacter cloacae Complex and Klebsiella pneumoniae Harbouring bla(CTX-M-15) and bla(CTX-M-55) Potentially Risk the Worldwide Spread of ESBL-Producing Bacteria Through Contaminated Dried Fishery Products. The transmission of life-threatening bacteria with plasmid-mediated antibiotic resistance poses a significant challenge to public health. This study aimed to determine the presence of plasmid-mediated antibiotic resistance genes in Enterobacterales isolates obtained from dried fishery products. Eighty-one dried fishery products were purchased from Vietnamese markets. Enterobacterales were isolated using a CHROMagar Escherichia coli coliform agar containing cefotaxime or meropenem. The isolated strains were assessed for their susceptibility to 14 antibiotics using a disc diffusion assay. Extended-spectrum β-lactamase (ESBL) sub-group typing was performed based on multiplex PCR of isolated ESBL-producing strains. In addition, Enterobacter cloacae AD2-1, which showed multiple drug resistance, was subject to whole-genome sequence analysis. CTX-resistant bacteria were isolated from 22% and MEM-resistant bacteria from 27% of the Vietnamese samples. CTX-resistant bacteria were isolated from 17% and MEM-resistant bacteria from 4% of Japanese samples. Bacterial identification indicated that 98 strains were isolated, of which 29 strains of E. coli, 28 of Enterobacter cloacae complex, 19 of Staphylococcus spp., and 9 of Klebsiella pneumoniae were predominant in Vietnamese samples. Japanese samples were predominantly contaminated with E. cloacae complex. Multiplex PCR and sequencing was used to determine the presence of ESBL-related genes bla(CTX-M-15) and bla(CTX-M-55) in E. cloacae and K. pneumoniae isolates. E. cloacae AD2-1 isolated from the Vietnamese dried fish was resistant to 14 antibiotics, and approximately 300 kbp of the IncHI2 plasmid harboured multiple antibiotic resistance genes and formed an antibiotic resistance gene region. This E. cloacae is considered a risk for the spread of antibiotic resistance across countries. | 2025 | 41171320 |
| 1049 | 6 | 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 |
| 1048 | 7 | 0.9999 | Characterizing the co-existence of metallo-β-lactamase-producing and extended-spectrum β-lactamase-producing Escherichia coli and Klebsiella pneumoniae isolates in community wastewater samples of Dhaka, Bangladesh. Escherichia coli and Klebsiella pneumoniae isolates with multiple antibiotic-resistance genes in wastewater pose serious public health risks, as they can potentially contaminate the food and water supply. The main aim of this study was to isolate and identify E. coli and K. pneumoniae from community wastewater samples, and determine their antibiotic-resistance profiles and their antibiotic-resistant genes. From the northern part of Dhaka, Bangladesh, 36 wastewater samples were collected across 11 different areas, which were then serially diluted, and cultured using selective media. Isolates were identified via polymerase chain reaction. Out of the 197 isolates identified, E. coli and K. pneumoniae accounted for 55.8% (n = 110) and 44.2% (n = 87), respectively. Antibiotic susceptibility tests revealed multidrug resistance (MDR) in 30% of E. coli and 35.56% of K. pneumoniae isolates. Among E. coli, the prevalence of antibiotic-resistance genes included bla(NDM-1) (8.9%), bla(SHV) (13.9%), and bla(CTX-M) (7.6%). In K. pneumoniae, the percentages were bla(NDM-1) (12.8%), bla(SHV) (4.3%), and bla(CTX-M) (5.0%). Co-existence of multiple antibiotic-resistance genes was observed in 4.54% of E. coli isolates (n = 5) and 5.74% of K. pneumoniae isolates (n = 5). This suggests the escalating issue of infectious species becoming increasingly resistant to antibiotics in wastewater systems. | 2025 | 40298266 |
| 946 | 8 | 0.9999 | Identification and Characterization of Multidrug-Resistant Extended-Spectrum Beta-Lactamase-Producing Bacteria from Healthy and Diseased Dogs and Cats Admitted to a Veterinary Hospital in Brazil. The objective of this study was to identify the main extended-spectrum beta-lactamase (ESBL)-producing bacteria and to detect the frequency of the major genes responsible to trigger this resistance in hospitalized animals. We collected 106 rectal swabs from cats (n = 25) and dogs (n = 81) to detect ESBL-producing isolates. ESBL-positive samples were submitted to the antimicrobial susceptibility test, and polymerase chain reaction was performed to detect TEM, SHV, and CTX-M genes from different groups. We observed that 44.34% of these samples (11 cats and 36 dogs) were positive for ESBL-producing bacteria. Thirteen animals (27.66%-seven cats and six dogs) were hospitalized for elective castration (healthy animals). Only a single animal was positive for ESBL-producing bacteria at hospital admission (the animal also showed an ESBL-positive isolate after leaving the hospital), whereas 11 were positive only at the hospital discharge. Of the 73 ESBL-producing isolates, 13 were isolated from cats (8 sick and 7 healthy) and 60 from dogs (53 sick and 7 healthy). Escherichia coli was the major ESBL-producing bacterium isolated (53.42%), followed by Pseudomonas aeruginosa (15.07%), Salmonella sp., and Proteus mirabilis (5.48% each one). Antimicrobial resistance profile of ESBL-producing isolates showed that 67 isolates (91.78%) were resistant to 3 or more antibiotic classes, while 13 of them (17.81%-2 healthy cats and 11 sick dogs) were resistant to all tested antimicrobial classes. The bla(TEM) gene exhibited the highest frequency in ESBL-producing isolates, followed by the bla(CTX-M) group 8/25, bla(CTX-M) group 1 and bla(CTX-M) group 9 genes. These results are useful to assess the predominance of ESBL-producing isolates recovered from dogs and in cats in Brazil. Consequently, we draw attention to these animals, as they can act as reservoirs for these microorganisms, which are the major pathogens of nosocomial infections worldwide. | 2021 | 33185513 |
| 1094 | 9 | 0.9998 | Detection of plasmid-mediated quinolone resistance genes in β-lactamase-producing Escherichia coli isolates from layer hens. This study was conducted to investigate the presence of plasmid-mediated quinolone resistance (PMQR) genes in β-lactamase-producing Escherichia coli isolates from layer hens and to characterize their molecular background. Among 142 E. coli isolates, 86 (60.6%) showed multidrug resistance and 15 (10.6%) were found to be β-lactamase-producing E. coli. Extended-spectrum β-lactamase (ESBL) and plasmid-mediated AmpC (pAmpC) β-lactamase genes, blaCTX-M-14 and blaCMY-2, were identified in three and six E. coli isolates, respectively. The non-ESBL or pAmpC gene, blaTEM-1, was found in eight of the isolates. Two isolates had both genes, blaCTX-M-14 and blaTEM-1. Among the 15 β-lactamase-producing E. coli, six PMQR genes, qnrS1 (n = 3) and qnrB4 (n = 3), were identified. Among the six PMQR-positive E. coli isolates, four exhibited double amino acid exchanges at both gyrA and parC with ciprofloxacin and enrofloxacin minimum inhibitory concentrations of ≥32 and ≥16 μg/mL, respectively. Additionally, five transconjugants (33.3%) showed a transferability of β-lactamase and PMQR genes. Pulsed-field gel electrophoresis (PFGE) analysis was conducted to investigate the 15 β-lactamase-producing E. coli isolates. In PFGE, E. coli included three PFGE patterns showing the same farms and in accordance with both β-lactamase and PMQR genes and the antimicrobial resistance pattern. Layer hens may act as a reservoir of antibiotic-resistant bacteria, and the PMQR gene in β-lactamase-producing E. coli isolates from layer hens has the potential to enter the food chain. Therefore, our findings suggest that comprehensive surveillance of antimicrobial use in laying operation systems is necessary. | 2019 | 30496543 |
| 945 | 10 | 0.9998 | Extended Spectrum Beta Lactamase (ESBL), bla(TEM),bla(SHV) and bla(CTX-M), Resistance Genes in Community and Healthcare Associated Gram Negative Bacteria from Osun State, Nigeria. BACKGROUND: Extended Spectrum Beta Lactamase (ESBL) production in gram negative bacteria confers multiple antibiotic resistance, adversely affecting antimicrobial therapy in infected individuals. ESBLs result from mutations in β-lactamases encoded mainly by the bla(TEM),bla(SHV) and bla(CTX-M) genes. The prevalence of ESBL producing bacteria has been on the increase globally, especially its upsurge among isolates from community-acquired infections has been observed. AIM: To determine ESBL prevalence and identify ESBL genes among clinical isolates in Osun State, Nigeria. MATERIAL AND METHODS: A cross-sectional study was carried out from August 2016 - July 2017 in Osun State, Nigeria. Three hundred and sixty Gram-negative bacteria recovered from clinical samples obtained from both community and healthcare-associated infections were tested. They included 147 Escherichia coli (40.8%), 116 Klebsiella spp (32.2%), 44 Pseudomonas aeruginosa (12.2%) and 23 Proteus vulgaris (6.4%) isolates. Others were Acinetobacter baumannii, Serratia rubidae, Citrobacter spp, Enterobacter spp and Salmonella typhi. Disk diffusion antibiotic susceptibility testing was carried out, isolates were screened for ESBL production and confirmed using standard laboratory procedures. ESBLs resistance genes were identified by Polymerase Chain Reaction (PCR). RESULTS: All isolates demonstrated multiple antibiotic resistance. Resistance to ampicillin, amoxicillin with clavulanate and erythromycin was 100%, whereas resistance to Imipenem was very low (5.0%). The overall prevalence of ESBL producers was 41.4% with Klebsiella spp as the highest ESBL producing Enterobacteriacaea. ESBL producers were more prevalent among the hospital pathogens than community pathogens, 58% vs. 29.5% (p=0.003). ESBL genes were detected in all ESBL producers with the bla(CTX-M) gene predominating (47.0%) followed by bla(TEM) (30.9%) and bla(SHV) gene was the least, 22.1%. The bla(CTX-M) gene was also the most prevalent in the healthcare pathogens (62%) but it accounted for only 25% in those of community origin. CONCLUSION: A high prevalence of ESBL producing gram-negative organisms occurs both in healthcare and in the community in our environment with the CTX-M variant predominating. Efforts to control the spread of these pathogens should be addressed. | 2021 | 32729432 |
| 1123 | 11 | 0.9998 | Molecular detection of blaSHV gene in multidrug resistance of Klebsiella pneumoniae isolated from chicken egg shell swab from a traditional market in Surabaya. BACKGROUND: Contamination with Klebsiella pneumoniae in food ingredients, including eggs, causes various dangers because it threatens public health, because it acts as a multidrug resistance (MDR) bacteria, especially the extended-spectrum beta-lactamase (ESBL) strain. The ESBL blaSHV gene is part of a broad-spectrum ESBL that is often found in Gram-negative bacteria. AIM: This study aimed to identify the ESBL blaSHV gene in K. pneumoniae MDR from chicken eggshells. METHODS: This study used 160 samples of chicken eggshell swabs isolated on 1% BPW media from 10 traditional Surabaya markets. Samples were isolated using MCA media and were identified using Gram staining and biochemical tests. Detection of MDR using Muller-Hinton Agar. RESULTS: Confirmation of ESBL in multidrug-resistant (MDR) isolates was performed using polymerase chain reaction to detect ESBL genes. The results showed that the isolation and identification of K. pneumoniae bacteria were 25.62% (41/160). Amoxicillin antibiotics showed the highest level of resistance at a percentage of 100% (41/41), followed by antibiotic resistance to erythromycin (90.24% (37/41), Streptomycin antibiotics were 26.82% (11/41), ciprofloxacin (14.63% (6/41), and Tetracycline antibiotic resistance was 7.31% (3/41). The results of MDR from K. pneumoniae showed 34.14% (14/41) of the isolates were then tested by PCR, which showed positive results for the blaSHV gene of 71.42% (10/14). CONCLUSION: The data from this study confirm the existence of K. pneumoniae bacteria isolated from egg shell swabs carrying the blaSHV gene from MDR isolates. | 2025 | 40557075 |
| 986 | 12 | 0.9998 | The Frequency of qnr Genes in Extended-Spectrum β-lactamases and non-ESBLs Klebsiella pneumoniae Species Isolated from Patients in Mashhad, Iran. BACKGROUND AND OBJECTIVES: Since the fluoroquinolones are the broad-spectrum antibiotics, they affect both Gram-negative and Gram-positive bacteria. These antibiotics are widely prescribed by physicians. As a result, some bacteria, especially Enterobacteriaceae, have shown a resistance to this family of antibiotics. The current study aimed at detecting the frequency of qnrA, qnrB, and qnrS genes, novel plasmid-mediated quinolone-resistance genes, among extended-spectrum β-lactamases (ESBL)-positive and ESBL-negative Klebsiella pneumoniae isolates. MATERIALS AND METHODS: One hundred and thirty isolates of K. pneumoniae were collected from Imam Reza Hospital and its associated clinics from May 2011 to July 2012. The isolates were tested for ESBLs by the conventional methods. Polymerase chain reaction (PCR) was performed to amplify qnr A, B, and S. RESULTS: Thirty-eight (29.3%) isolates were ciprofloxacin-resistant. Among 130 K. pneumoniae infectious isolates, 56 (43%) were capable of producing ESBL; 10.8% (n=14), 15.4% (n=20), and 20.8% (n=27) of ESBL-producing K. pneumonia were positive for qnrA, qnrS, and qnrB, respectively, and 13.8% (n=18) of the isolates harbored 2 or 3 qnr genes. CONCLUSION: The results of the current study showed that quinolone-resistance genes were more frequent in ESBL-producing K. pneumoniae (37.5%) isolates, compared with the ESBL-negative isolates (20.89%). The prevalence of qnr genes was high in K. pneumoniae isolates, with higher frequency in ESBL-positive strains. Most of the isolates were positive for all 3 groups of qnr genes and the qnrB was the most common one. | 2017 | 29563934 |
| 1116 | 13 | 0.9998 | Detection of blaCTX-M genes in ESBL-producing Klebsiella isolates from animals in Croatia. This study investigated the frequency of third-generation cephalosporin resistance in Klebsiella spp. isolated from animals in Croatia and the presence of blaCTX-M genes. A total of 711 enteric bacteria were isolated from clinical samples, and Klebsiella spp. isolates accounted for 6.9% (n = 49). Thirteen Klebsiella isolates (26.5%) were ESBL producers, nine isolates from the Klebsiella pneumoniae species complex (69.2%), and four (30.8%) Klebsiella oxytoca isolates. All carried the blaCTX-M-15 gene, and antimicrobial susceptibility testing revealed them as multidrug resistant. All were resistant to all tested cephalosporins, fluoroquinolones, aminoglycosides and aztreonam, 92.3% showed resistance to tetracycline, 84.6% to trimethoprim-sulfamethoxazole and 69.2% to nitrofurantoin. No isolate showed resistance to imipenem and meropenem. It can be concluded that ESBL-producing Klebsiella expressing the blaCTX-M gene are not rare among Klebsiella isolates from animals in Croatia. | 2023 | 37027245 |
| 1446 | 14 | 0.9998 | One-Day Prevalence of Extended-Spectrum β-Lactamase (ESBL) and Carbapenemase-Producing Bacteria in Fecal Samples from Surgical Patients: A Concerning Trend of Antibiotic Resistance. PURPOSE: Extended-spectrum β-lactamase (ESBL) and carbapenemase producing bacteria are of increasing concern due to their multidrug resistance and infection potential. This study determines the one-day prevalence of faecal carriage of ESBL and carbapenemase producing Gram-negative bacilli. METHODS: Fecal samples were collected from 30 post-surgery patients (hospitalized for at least 48 hours) in each of the four hospitals involved in the study and were analyzed for antibiotic-resistant bacteria. Identification was done using Maldi Tof mass spectrometry, and antibiotic susceptibility was tested using disk diffusion and specialized tests for ESBL (double disk synergy technique) and carbapenem (NG-TEST CARBA 5) resistance detection. PCR was conducted on isolates to detect betalactam resistance genes, carbapenemase genes and quinolone resistance genes. FINDINGS: Out of the 120 patients enrolled, 38.33% (n = 46) and 49.16.33% (n = 59) were found to carry ESBL- and carbapenemase-producing bacteria, respectively, in their fecal samples. Among the isolates, 51.08% (n = 47) exhibited ESBL production, with Escherichia coli (44.56%) being the most common species. The identification of bacteria with resistance to carbapenems showed a predominance of the species Escherichia coli (44.45%) followed by the species Klebsiella pneumoniae (16.06%) and Acinetobacter baumanii (13.58%). The study of the association of variables shows a high degree of association (p < 0.05) for the factors independent walking and use of a wheelchair with ESBL production. The most frequently detected genes among ESBL producing bacteria were bla(CTXM-1) (91.49%), qnrB (70.21%) and qnrs (63.82%). bla(NDM) (54.68%) was the most detected carbapenemase genes among carbapenemase producing isolates. CONCLUSION: This study demonstrates, for the first time, a significant prevalence of ESBL and carbapenemase producing gram-negative bacteria among surgical patients in Benin, with multiple resistance genes detected. Findings should be interpreted in light of the cross-sectional design and >48-hour hospitalization criterion. | 2025 | 40635768 |
| 987 | 15 | 0.9998 | Characterization of Multidrug Resistant Extended-Spectrum Beta-Lactamase-Producing Escherichia coli among Uropathogens of Pediatrics in North of Iran. Escherichia coli remains as one of the most important bacteria causing infections in pediatrics and producing extended-spectrum beta-lactamases (ESBLs) making them resistant to beta-lactam antibiotics. In this study we aimed to genotype ESBL-producing E. coli isolates from pediatric patients for ESBL genes and determine their association with antimicrobial resistance. One hundred of the E. coli isolates were initially considered ESBL producing based on their MIC results. These isolates were then tested by polymerase chain reaction (PCR) for the presence or absence of CTX, TEM, SHV, GES, and VEB beta-lactamase genes. About 30.5% of isolated E. coli was ESBL-producing strain. The TEM gene was the most prevalent (49%) followed by SHV (44%), CTX (28%), VEB (8%), and GES (0%) genes. The ESBL-producing E. coli isolates were susceptible to carbapenems (66%) and amikacin (58%) and showed high resistance to cefixime (99%), colistin (82%), and ciprofloxacin (76%). In conclusion, carbapenems were the most effective antibiotics against ESBl-producing E. coli in urinary tract infection in North of Iran. The most prevalent gene is the TEM-type, but the other resistant genes and their antimicrobial resistance are on the rise. | 2015 | 26064896 |
| 1115 | 16 | 0.9998 | Prevalence of extended spectrum beta lactamase and plasmid mediated quinolone resistant genes in strains of Klebsiella pneumonia, Morganella morganii, Leclercia adecarboxylata and Citrobacter freundii isolated from poultry in South Western Nigeria. A serious concern is arising on the coexistence of extended-spectrum beta-lactamase (ESBL) and plasmid mediated quinolone resistance (PMQR) producing bacteria in animal husbandry, which could be transferred to humans, especially in strains that may not be routinely screened for resistance. This study therefore tested the prevalence of ESBL and PMQR genes in selected bacteria isolated from poultry faeces. Faecal droppings of birds were collected from 11 farms in five states in South Western Nigeria. Bacteria were isolated from the samples on cefotaxime supplemented plates and identified with MALDI-TOF. The MIC was determined using VITEK system and resistance genes were detected with PCR. A total of 350 strains were isolated from different samples and selected strains were identified as 23 Klebsiella pneumonia, 12 Morganella morganii, seven Leclercia adecarboxylata and one Citrobacter freundii. All the species were resistant to gentamycin, trimethoprim/sulphamethaxole, tobramycin, piperacillin, cefotaxime and aztreonam (except Morganella morganii strains which were mostly susceptible to aztreonam). All the tested strains were susceptible to imipenem, meropenem and amikacin. All Leclercia adecarboxylata strains were resistant to ceftazidime, cefepime and fosfomycin while all Morganella morganii strains were resistant to fosfomycin, moxifloxacin and ciprofloxacin. All tested species were generally sensitive to ciprofloxacin except Morganella morganii strains which were resistant to ciprofloxacin. The resistance to ciprofloxacin, ceftazidime, cefepime, tigercylin, colistin and fosfomycin were 65%, 40%, 23%,, 7%, 33%, 48% respectively while the prevalence of SHV, TEM and CTX genes were 42%, 63%, 35% respectively. 9.3% of the isolates had the three ESBL genes, 2.33% had qnrA gene, 4.65% had qnr B gene while none had qnrS gene. The most prevalent PMQR gene is Oqxb (25.58%) while 6.98% had the qep gene. Klebsiella pneumoniae generally had both ESBL and PMQR genes. The high prevalence of extended spectrum beta-lactamase genes in the studied strains calls for caution in the use of beta lactam antibiotics in poultry feeds. This is the first report of the occurrence of extended spectrum beta-lactamase and plasmid mediated quinolone resistance genes in Morganella morganii and Leclercia adecarboxylata strains isolated from poultry faeces. | 2018 | 29942700 |
| 1050 | 17 | 0.9998 | Antibiotic resistance and β-lactam resistant genes among bacterial isolates from clinical, river water and poultry samples from Kathmandu, Nepal. OBJECTIVE: To assess the antibiotic resistance and beta-lactam resistance genes among bacterial isolates from clinical, river water and poultry samples. METHODS: Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa were isolated from clinical, poultry and river water samples collected during 2020-22. They were subjected to antimicrobial susceptibility tests following the CLSI guidelines. The bacteria were screened for β-lactam resistance genes bla (TEM), mcr-1, mecA and bla(NDM-1) . RESULTS: Among 2835 clinical samples, E. coli was the most frequently isolated bacterium (10.3%, 292), followed by S. aureus (6.0%, 169) and P. aeruginosa (4.0%, 143). Of the E. coli isolates, 64.4% exhibited multidrug resistance (MDR) and 43.8% were extended-spectrum β-lactamase (ESBL) producers, with 44.5% and 16.4% harbouring the blaTEM and mcr-1 genes, respectively. Among S. aureus isolates, 80.9% of methicillin-resistant strains (MRSA) carried the mecA gene, while 30.1% of metallo-β-lactamase (MBL)-producing P. aeruginosa were positive for the blaNDM-1 gene. In poultry samples, 30.4% of E. coli isolates harboured the blaTEM gene among 128 ESBL producers, and the prevalence of colistin-resistant isolates carrying mcr-1 was higher than in clinical samples. In contrast, the occurrence of ESBL-producing E. coli and MRSA, along with their associated resistance genes, was lower in water samples. CONCLUSIONS: This study demonstrated widespread multidrug resistance (MDR) and ESBL production among clinical, poultry and river water bacterial isolates in the Kathmandu valley. Colistin-resistant E. coli carrying the mcr-1 gene, methicillin-resistant S. aureus (MRSA) with mecA and metallo-β-lactamase (MBL)-producing P. aeruginosa harboring blaNDM-1 were detected across sources. These findings emphasize an urgent One Health approach to curb the growing threat of antimicrobial resistance in the region. | 2025 | 41113068 |
| 1054 | 18 | 0.9998 | Molecular detection of extended-spectrum β-lactamase-producing Klebsiella pneumoniae isolates of chicken origin from East Java, Indonesia. BACKGROUND AND AIM: Klebsiella pneumoniae is one of the respiratory disease agents in human and chicken. This bacterium is treated by antibiotic, but this treatment may trigger antibiotic resistance. Resistance gene in K. pneumoniae may be transferred to other bacteria. One of the known resistance genes is extended-spectrum β-lactamase (ESBL). This research aimed to study K. pneumoniae isolated from chicken farms in East Java, Indonesia, by observing the antibiotic resistance pattern and detect the presence of ESBL coding gene within the isolates. MATERIALS AND METHODS: A total of 11 K. pneumoniae isolates were collected from 141 chicken cloacal swabs from two regencies in East Java. All isolates were identified using the polymerase chain reaction method. Antimicrobial susceptibility was determined by agar dilution method on identified isolates, which then processed for molecular characterization to detect ESBL coding gene within the K. pneumoniae isolates found. RESULTS: The result of antibiotic sensitivity test in 11 isolates showed highest antibiotic resistance level toward ampicillin, amoxicillin, and oxytetracycline (100%, 100%, and 90.9%) and still sensitive to gentamicin. Resistance against colistin, doxycycline, ciprofloxacin, and enrofloxacin is varied by 90.9%, 54.5%, 27.3%, and 18.2%, respectively. All isolates of K. pneumoniae were classified as multidrug resistance (MDR) bacteria. Resistance gene analysis revealed the isolates harbored as bla (SHV) (9.1%), bla (TEM) (100%), and bla (CTX-M) (90.9%). CONCLUSION: All the bacterial isolates were classified as MDR bacteria and harbored two of the transmissible ESBL genes. The presence of antibiotic resistance genes in bacteria has the potential to spread its resistance properties. | 2019 | 31190714 |
| 1070 | 19 | 0.9998 | Survey for beta-lactamase among bacterial isolates from Guangzhou, China hospitals between 2005-2006. The beta-lactamase genes, which confer multi-drug resistance, are spreading among clinical bacterial isolates. As part of a routine surveillance program, we collected 302 bacilli isolates between June 2005 and October 2006 from four hospitals in Guangzhou, China. The isolates were screened for multidrug resistance and for the presence of beta-lactamases. In all, 80 isolates were identified as multidrug-resistant with the K-B method. These isolates were phenotypically screened for beta-lactamase activity by disk diffusion prescreening, diffusion confirmation, the cefoxitin three-dimensional test and the metallo-beta-lactamase (MBL) synergy test. Bacteria were genotypically screened for beta-lactamase genes by PCR and DNA sequencing. Among the 80 strains, drug resistance was lowest to amikacin (18.75%) and highest to ampicillin (97.50%), 26.49% had a beta-lactamase phenotype, 16.56% had the extended-spectrum beta-lactamase (ESBL) phenotype, 24.83% had a beta-lactamase genotype, 51 carried integrons, 30 carried class I integrons and 18.75% had the ISEcp1B insertion sequence. Sequencing also detected a new CTX-M ESBL gene subtype, which had an ISEcp1B element upstream of bla(CTX-M-Like), and an IS903 element downstream, forming a composite transposon. Multidrug resistance and beta-lactamases continue to be prevalent in Guangzhou. Our results suggest that resistance genes are evolving and being horizontally transmitted between species. | 2010 | 20339396 |