# | Rank | Similarity | Title + Abs. | Year | PMID |
|---|---|---|---|---|---|
| 0 | 1 | 2 | 3 | 4 | 5 |
| 1315 | 0 | 0.9985 | Neonatal calf diarrhea: A potent reservoir of multi-drug resistant bacteria, environmental contamination and public health hazard in Pakistan. Though emergence of multi-drug resistant bacteria in the environment is a demonstrated worldwide phenomenon, limited research is reported about the prevalence of resistant bacteria in fecal ecology of neonatal calf diarrhea (NCD) animals in Pakistan. The present study aimed to identify and assess the prevalence of bacterial pathogens and their resistance potential in the fecal ecology of NCD diseased animals of Pakistan. The presence of antibiotic resistance genes (bla(TEM), bla(NDM-1), bla(CTX-M), qnrS) was also investigated. A total of 51 bacterial isolates were recovered from feces of young diarrheic animals (n = 11), collected from 7 cities of Pakistan and identified on the basis of 16S rRNA gene sequence and phylogenetic analysis. Selected isolates were subjected to antimicrobial susceptibility by disc diffusion method while polymerase chain reaction (PCR) was used to characterize the bla(TEM), bla(NDM-1), bla(CTX-M), qnrS and mcr-1 antibiotic resistance genes. Based on the 16S rRNA gene sequences (Accession numbers: LC488898 to LC488948), all isolates were identified that belonged to seventeen genera with the highest prevalence rate for phylum Proteobacteria and genus Bacillus (23%). Antibiotic susceptibility explained the prevalence of resistance in isolates ciprofloxacin (100%), ampicillin (100%), sulfamethoxazole-trimethoprim (85%), tetracycline (75%), amoxicillin (55%), ofloxacin (50%), ceftazidime (45%), amoxicillin/clavulanic acid (45%), levofloxacin (30%), cefpodoxime (25%), cefotaxime (25%), cefotaxime/clavulanic acid (20%), and imipenem (10%). MICs demonstrated that almost 90% isolates were multi-drug resistant (against at least three antibiotics), specially against ciprofloxacin, and tetracycline with the highest resistance levels for Shigella sp. (NCCP-421) (MIC-CIP up to 75 μg mL(-1)) and Escherichia sp. (NCCP-432) (MIC-TET up to 250 μg mL(-1)). PCR-assisted detection of antibiotic resistance genes showed that 54% isolates were positive for bla(TEM) gene, 7% isolates were positive for bla(CTX-M) gene, 23% isolates were positive for each of qnrS and mcr-1 genes, 23% isolates were co-positive in combinations of qnrS and mcr-1 genes and bla(TEM) and mcr-1 genes, whereas none of the isolate showed presence of bla(NDM-1) gene. | 2021 | 34426357 |
| 1028 | 1 | 0.9985 | Antibiotic resistance and extended-spectrum β-lactamases in isolated bacteria from seawater of Algiers beaches (Algeria). The aim of the study was to evaluate bacterial antibiotic resistance in seawater from four beaches in Algiers. The most significant resistance rates were observed for amoxicillin and ticarcillin, whereas they were relatively low for ceftazidime, cefotaxime and imipenem. According to sampling sites, the highest resistance rates were recorded for 2 sites subjected to chemical and microbiological inputs (amoxicillin, 43% and 52%; ticarcillin, 19.6% and 47.7%), and for 2 sites relatively preserved from anthropogenic influence, resistance rates were lowest (amoxicillin, 1.5% and 16%; ticarcillin, 0.8% and 2.6%). Thirty-four bacteria resistant to imipenem (n=14) or cefotaxime (n=20) were identified as Pseudomonas aeruginosa (n=15), Pseudomonas fluorescens (7), Stenotrophomonas maltophilia (4), Burkholderia cepacia (2), Bordetella sp. (1), Pantoea sp. (1), Acinetobacter baumannii (1), Chryseomonas luteola (1), Ochrobactrum anthropi (1) and Escherichia coli (1). Screening for extended spectrum β-lactamase showed the presence of CTX-M-15 β-lactamase in the E. coli isolate, and the encoding gene was transferable in association with the IncI1 plasmid of about 50 kbp. Insertion sequence ISEcp1B was located upstream of the CTX-M-15 gene. This work showed a significant level of resistance to antibiotics, mainly among environmental saprophytic bacteria. Transmissible CTX-M-15 was detected in E. coli; this may mean that contamination of the environment by resistant bacteria may cause the spread of resistance genes. | 2012 | 22095134 |
| 1294 | 2 | 0.9985 | Isolation and detection of antibiotics resistance genes of Escherichia coli from broiler farms in Sukabumi, Indonesia. OBJECTIVE: This study aimed to isolate and identify Escherichia coli from broiler samples from Sukabumi, Indonesia. Also, antibiogram studies of the isolated bacteria were carried out considering the detection of the antibiotic resistance genes. MATERIALS AND METHODS: Cloaca swabs (n = 45) were collected from broilers in Sukabumi, Indonesia. Isolation and identification of E. coli were carried out according to standard bacteriological techniques and biochemical tests, followed by confirmation of the polymerase chain reaction targeting the uspA gene. Antibiotic sensitivity test, using several antibiotics [tetracycline (TE), oxytetracycline (OT), ampicillin (AMP), gentamicin (CN), nalidixic acid (NA), ciprofloxacin (CIP), enrofloxacin (ENR), chloramphenicol, and erythromycin] was carried out following the Kirby-Bauer disk diffusion method. Detection of antibiotic resistance coding genes was carried out by PCR using specific oligonucleotide primers. Statistical analysis was carried out with one-way analysis of variance. RESULTS: The results showed that 55.6% (25/45) of the samples were associated with the presence of E. coli. Antibiotic sensitivity test showed that the E. coli isolates were resistant to TE (88%; 22/25), OT (88%; 22/25), AMP (100%; 25/25), CN (64%; 16/25), NA (100%; 22/25), CIP (88%; 22/25), ENR (72%; 18/25), chloramphenicol (0%; 0/25), and erythromycin (92%; 23/25). On the other hand, the antibiotic resistance coding genes were tetA (86.4%; 19/22), blaTEM (100%; 25/25), aac(3)-IV (0%; 0/16), gyrA (100%; 25/25), and ermB (13%; 3/23). It was found that chloramphenicol is markedly different from other antibiotic treatment groups. CONCLUSION: Escherichia coli was successfully isolated from cloacal swabs of broiler in Sukabumi, Indonesia. The bacteria were resistant to TE, OT, AMP, CN, NA, CIP, ENR, and erythromycin. Chloramphenicol was more sensitive and effective than other antibiotics in inhibiting the growth of E. coli. The antibiotic resistance genes detected were tetA, blaTEM, gyrA, and ermB. | 2021 | 33860017 |
| 2136 | 3 | 0.9985 | Antibiotic profiling of multidrug resistant pathogens in one-day-old chicks imported from Belgium to benin. BACKGROUND: Little data exist on the presence of resistant pathogens in day-old chicks imported into Benin. The occurrence of pathogenic bacteria was assessed in 180 one-day-old chicks imported from Belgium and received at the Cardinal Bernardin Gantin International Airport in Cotonou (Benin). The samples included swabbing the blisters of 180 chicks, followed by 18 pools of 10 swabs for bacterial isolation. Classic bacteriological methods based on Gram staining, culture on specific media and biochemical characterization were used. Antibacterial susceptibility screening to antibiotics was conducted using the Kirby-Bauer disc diffusion method, and the results were interpreted according to guidelines from the European Committee on Antimicrobial Susceptibility Testing (EUCAST). DNA extraction was performed by the heat treatment method. Resistance genes were screened by real-time PCR. RESULTS: We isolated 32 bacteria, including Escherichia coli (50%), Enterococcus spp. (28%), and coagulase-negative staphylococci (10%). The isolates were investigated for antibiotic resistance against antibiotics using the disk diffusion method and showed that in the Escherichia coli strains isolated, the highest rate of resistance was obtained against ciprofloxacin (81%), followed by trimethoprim + sulfamethoxazole (62%). Enterobacter cloacae was sensitive to all the antibiotics tested. Pseudomonas spp. resistant to amoxicillin and trimethoprim + sulfamethoxazole was noted. The SulII gene was found in all cloacal samples, while the SulI and bla(TEM) genes were present at 44.44% and 16.67%, respectively. CONCLUSION: This study confirms that imported day-old chicks can be a potential source of dissemination of resistant bacteria in poultry production. A system for immediate detection of resistant bacteria in chicks upon arrival in the country is thus needed. | 2023 | 36670436 |
| 1178 | 4 | 0.9985 | Molecular Characterization of Plasmid-Mediated Quinolone Resistance Genes in Multidrug-Resistant Escherichia coli Isolated From Wastewater Generated From the Hospital Environment. AIM: This study investigated the carriage of Plasmid-Mediated Quinolone Resistance (PMQR) genes in fluoroquinolone-resistant Escherichia coli recovered from wastewater generated by healthcare institutions. MATERIALS AND METHODS: Isolation of fluoroquinolone-resistant Escherichia coli was done on medium supplemented with 1 µg/mL of ciprofloxacin (a fluoroquinolone). Presumptive isolates were identified via the detection of uidA gene. Susceptibility of the isolates to a panel of antibiotics was done using disc diffusion method. Detection of PMQR genes in the isolates was done using primer-specific PCR. RESULTS: Thirty fluoroquinolone-resistant Escherichia coli were obtained from the wastewater over a period of 6 months. The resistance to each of the antibiotic tested was: ampicillin (100%), ceftriaxone (100%), nalidixic acid (100%), tetracycline (96.7%), cefotaxime (96.7%), amoxicillin-clavulanate (80%), gentamicin (60%), cefoxitin (30%), and imipenem (3.3%). The Multiple Antibiotic Resistance Index (MARI) ranged from 0.6 to 0.9. The detection of PMQR genes in the 30 isolates was: qnrA (76.7%), qnrB (53.3%), qnrS (63.3%), aac(6')-lb-cr (43.3%), and qepA (43.3%). All the fluoroquinolone-resistant Escherichia coli carried at least one PMQR determinant. CONCLUSION: This study revealed that untreated hospital wastewaters are significant hub of multidrug-resistant and fluoroquinolone-resistant Escherichia coli, showing high carriage of PMQR genes, and may be a major contributor to the resistome of fluoroquinolone-resistant bacteria in the Nigerian environment. | 2025 | 40552214 |
| 1177 | 5 | 0.9985 | High carriage of plasmid-mediated quinolone resistance (PMQR) genes by cefotaxime-resistant Escherichia coli recovered from surface-leaking sanitary sewers. There is a rapid rise in the incidence of quinolone resistant bacteria in Nigeria. Most studies in Nigeria have focused on isolates from the clinical settings, with few focusing on isolates of environmental origin. This study aimed to investigate the antibiogram and carriage of plasmid-mediated quinolone resistance (PMQR) genes by quinolone-resistant isolates obtained from a pool of cefotaxime-resistant Escherichia coli (E. coli) recovered from sewage leaking out of some surface-leaking sanitary sewers in a University community in Nigeria. Isolation of E. coli from the sewage samples was done on CHROMagar E. coli, after enrichment of the samples was done in Brain Heart Infusion broth amended with 6 µg/mL of cefotaxime. Identification of presumptive E. coli was done using molecular methods (detection of uidA gene), while susceptibility to antibiotics was carried out using the disc diffusion method. Detection of PMQR genes (qnrA, qnrB, qnrS, aac(6')-lb-cr, qepA and oqxAB) was carried out using primer-specific PCR. A total of 32 non-repetitive cefotaxime-resistant E. coli were obtained from the sewage, with 21 being quinolone-resistant. The quinolone-resistant isolates showed varying level of resistance to the tested antibiotics, with imipenem being the only exception with 0% resistance. The PMQR genes: aac(6')-lb-cr, qnrA, qnrB, qnrS and qepA and oqxAB were detected in 90.5%, 61.9%, 47.6%, 38.1%, 4.8% and 0% respectively of the isolates. The findings of this study showed a high level of resistance to antibiotics and carriage of PMQR genes by quinolone-resistant E. coli obtained from the leaking sanitary sewers, suggesting a potential environmental and public health concern. | 2022 | 35000007 |
| 1181 | 6 | 0.9984 | Plasmid-mediated quinolone resistance genes transfer among enteric bacteria isolated from human and animal sources. This research investigates the transferability of plasmid-mediated quinolone resistance (PMQR) genes among enteric bacteria isolates in human and animal samples, as well as its implication on resistance of recipient cells. A total of 1,964 strains of five different enteric bacteria species (Escherichia coli, Salmonella sp., Shigella sp., Klebsiella sp. and Aeromonas sp.) were screened for plasmid-mediated quinolone resistance (PMQR) genes from a population of quinolone resistant (Q-r) isolates. Screening for PMQR isolates was achieved by plasmid curing using sub-lethal concentration of Sodium Dodecyl Sulphate and PMQR genes (qnrA, qnrB, qnrS, Aac(6')-Ib-crand Qep A) were detected by polymerase chain reaction (PCR). Conjugation and transformation experiments were attempted to ascertain transfer of genes from the Q-r isolates to a susceptible, standard recipient, E. coli J53-2. The minimum inhibitory concentration (MIC) was determined before and after gene transfer, using E-test strips. Results indicate that percentage resistance to the quinolones (Qs): Nalidixic acid, Ciprofloxacin, Pefloxacin and Ofloxacin determined by agar plate diffusion technique stood at 52.6, 47.3, 50.5, 70.6 and 46.0% for Escherichia coli, Salmonella sp., Shigellasp., Klebsiella sp. and Aeromonas sp. respectively. Analysis of variance indicated the occurrence of significant differences (F, 46.77-613.30; 0.00) in the resistance to each tested Qs. Generally, Human isolates showed greater resistance than Animal isolates (57.4 vs 47.2%). Investigation with specific primers indicated 11, 15, 7, 1 and 0 for qnrA, qnrB, qnrS, qepA and Aac(6')-Ib-cr genes respectively, out of 1018 Q-r and 29 PMQR isolates. Gene transfer experiments indicated the transfer of all genes except qepA either by conjugation or transformation. The MIC of tested Qs on recipient bacterium before gene transfer greatly increased from 0.0625 to 0.25 µg/mL, after transfer. This study demonstrates that PMQR genes amongst enteric bacteria in the Niger delta of Nigeria were transferable and transfer conferred a higher Q- resistance on recipient bacterium. | 2021 | 34250375 |
| 1314 | 7 | 0.9984 | Antibiotic resistance genes, colistin-resistant Escherichia coli, and physicochemicals in health care wastewater in Vinh Long General Hospital, Vietnam. This study collected ten treated wastewater samples from Vinh Long General Hospital to determine their physicochemical characteristics and antibiotic properties. All treated wastewater samples collected during the monitoring periods complied with national regulations. In addition, these samples did not contain bacteria such as Salmonella, Shigella, and Vibrio cholerae. The investigation yielded a total of 25 Escherichia coli isolates. The E. coli isolates exhibied highest antibiotic resistance rate to ampicillin (100%), followed by ciprofloxacin, amoxicillin/clavulanic acid, and cefazolin (96%, 92%, and 92%, respectively). The resistance rate to fosfomycin was 88%, whereas 80% of the isolates were resistant to sulfamethoxazole-trimethoprim. The resistance rate to gentamicin was 72%, whereas that to imipenem and tetracycline was 52%. In addition, 44% isolates were resistant to chloramphenicol, and 32% of isolates were colistin-resistant. Among analyzed isolates, three were resistant to 10 of 11 tested antibiotics but only displayed intermediate resistance to imipenems (carbapenems). Surprisingly, 23 out of 25 isolates showed a positive ESBL phenotype. Eleven of them had both the bla(TEM) and bla(CTX-M-1) group structural genes, while twelve only had the bla(CTX-M-1) group gene. Furthermore, none of the isolated E. coli isolates exhibited the bla(SHV) gene. The minimum inhibitory concentration (MIC) of colistin exceeded 4 μg/mL in 8 out of 25 (32%) isolates. Seven of eight isolates (87.5%) carried the mcr-1 gene, while one (12.5%) carried the mcr-8 gene. None of the other mcr (mcr-2 to mcr-9) genes were found. | 2024 | 39528737 |
| 1031 | 8 | 0.9984 | Beta-lactams resistance and presence of class 1 integron in Pseudomonas spp. isolated from untreated hospital effluents in Brazil. The aim of the present study was to investigate the resistance profile, to detect the presence of beta-lactam resistance genes, phenotypic expression of efflux pump systems and class 1 integrons in Pseudomonas spp. strains obtained from untreated hospital effluents. Effluent samples were collected from four hospitals in Porto Alegre, RS, Brazil. Pseudomonas were isolated on MacConkey agar plates and the identification was confirmed by 16S rRNA PCR and biochemical tests. Susceptibility testing was determined by disk-diffusion method using 11 different beta-lactams and MIC assays were performed on isolates resistant to imipenem and ceftazidime. The beta-lactamase genes bla (IMP), bla (VIM), bla (SPM-1), bla (OXA-23-like), bla (OXA-24-like), bla (OXA-51-like) and the intl1 gene from class 1 integron were analysed by PCR. One hundred and twenty-four isolates were recovered and the most common species was Pseudomonas pseudoalcaligenes. The resistance found among the isolates was considered high, 62 (50%) isolates were multiresistant. No isolate carrying the beta-lactamase genes tested was found among the strains. Seven isolates showed reduction of MIC for imipenem and ceftazidime in the presence of cyanide m-chlorophenylhydrazone, indicating the hyper expression of efflux pumps. From the 124 isolates, 52 (41.9%) were identified as carrying the class 1 integron gene, intI1. Untreated hospital effluents could be a source of environmental contamination due to discharge of antimicrobial resistant bacteria which can carry integron class 1 and act as a reservoir of resistance genes and have efflux pump systems. | 2012 | 22382676 |
| 1125 | 9 | 0.9984 | Detection of emerging antibiotic resistance in bacteria isolated from subclinical mastitis in cattle in West Bengal. AIM: The aim of this work was to detect antibiotic resistance in Gram-negative bacteria isolated from subclinical mastitis in cattle in West Bengal. MATERIALS AND METHODS: The milk samples were collected from the cattle suffering with subclinical mastitis in West Bengal. The milk samples were inoculated into the nutrient broth and incubated at 37°C. On the next day, the growth was transferred into nutrient agar and MacConkey agar. All the pure cultures obtained from nutrient agar slant were subjected to Gram-staining and standard biochemical tests. All the bacterial isolates were tested in vitro for their sensitivity to different antibiotics commonly used in veterinary practices. All Gram-negative isolates including positive control were subjected to polymerase chain reaction (PCR) for detection of bla(CTX-M), bla(TEM), bla(SHV), bla(VIM), tetA, tetB, tetC, and tetM genes considered for extended-spectrum β-lactamase (ESBL), metallo-β-lactamase, and tetracycline resistance. RESULTS: In total, 50 Gram-negative organisms (Escherichia coli, Proteus, Pseudomonas, Klebsiella, and Enterobacter) were isolated from milk samples of subclinical mastitis infected cattle. Among these Gram-negative isolates, 48% (24/50) were found either ESBL producing or tetracycline resistant. Out of total 50 Gram-negative isolates, bla(CTX-M) was detected in 18 (36%) isolates, and 6 (12%) harbored bla(TEM) genes in PCR. None of the isolates carried bla(SHV) genes. Further, in this study, 5 (10%) isolates harbored tet(A) gene, and 8 (16%) isolates carried tet(B) gene. No tet(C) gene was detected from the isolates. CONCLUSION: This study showed emerging trend of antibiotic-resistant Gram-negative bacteria associated with subclinical mastitis in cattle in West Bengal, India. | 2017 | 28620255 |
| 2100 | 10 | 0.9984 | Prevalence of Bacteria and Antimicrobial Resistance Genes in Hospital Water and Surfaces. Purpose Antimicrobial resistance (AMR) has become a worldwide environmental and public health problem, causing more than 250,000 deaths per year. Unregulated usage, unsafe hospital practices, and misuse in veterinary contribute to the development of multidrug resistance in various bacteria. Hospital water was hypothesized to be a hotspot for AMR transmission because of (1) increased exposure to antibiotic load, (2) poor drainage and sanitation system, (3) interaction between environmental and clinical microbes. The purpose of the research was to assess the biodiversity and AMR in hospital tap waters. Methodology In this study, the microflora of the hospital tap water and hospital surfaces was observed by obtaining water samples from the intensive care unit (ICU), surgical wards, and washrooms. These were processed through membrane filtration and spread on seven different media (Aeromonas Medium, Azide Dextrose Agar, MacConkey Agar, Mannitol Salt Agar, Pseudomonas Cetrimide Agar, Salmonella Shigella Agar, and Thiosulfate Citrate Bile Salts Sucrose Agar). Surface samples were collected from the faucet, basin, and drain and directly spread on the media plates. Isolates were identified using standard bacteriological and biochemical tests. Kirby-Bauer disk diffusion method was performed using 21 antibiotic disks from 10 different antibiotic classes. They included ampicillin (AMP), amoxicillin (AML), piperacillin-tazobactam (TZP), cefipime (FEP), cefoxitin (FOX), ceftazidime (CAZ), ceftriaxone (CRO), imipenem (IMP), meropenem (MEM), ciprofloxacin (CIP), moxifloxacin (MXF), levofloxacin (LEV), amikacin (AK), gentamicin (CN), tigecycline (TGC), aztreonam (ATM), erythromycin (E), clindamycin (DA), rifampicin (RD), colistin (CT), and chloramphenicol (C). The results were interpreted according to EUCAST guidelines for the antibiogram of the isolates; 38 isolates were selected out of 162 based on different parameters for genotyping and detection of six beta-lactamase genes (blaSHV, blaTEM, blaCTX-M, blaOXA, blaKPC, blaNDM). Results Among these 162 isolates, 82 were obtained from water sources and 80 were collected from surfaces (faucet, basin, drain). The isolates included a variety of bacteria including Aeromonas spp. (20%), Klebsiella spp. (13%), Staphylococcus aureus (13%), Pseudomonas spp.(10%), Escherichia coli (9%), Vibrio spp. (8%), Enterococcus spp. (6%), Shigella spp. (6%), Salmonella spp. (4%), Acinetobacter spp. (3%), Staphylococcus epidermitis (3%), Streptococci spp. (2%), Proteus spp. (1%), Citrobacter spp. (1%), and Serratia spp. (1%). A diverse range of microbes were identified including clinically relevant bacteria, which shows that the urban water cycle is already contaminated with multidrug-resistant microflora of the hospital settings. Macrolide and lincosamide showed the highest resistance followed by penicillin, monobactam, and cephalosporins. blaSHV and blaTEM were prevalent in samples. blaNDM was also found which manifests as a real threat since it causes resistance against carbapenems and colistin, antibiotics reserved as a last resort against infections. Conclusions This study presented the ground reality of antibiotic resistance in Pakistan and how its subsequent spread poses a great threat to the strides made in the field of medicine and public health. Strict regulations regarding antibiotic usage, hospital effluent, and urban water sanitation must be imposed to curb the devastating effects of this increasing phenomenon. | 2021 | 34790487 |
| 1169 | 11 | 0.9984 | Determination and molecular analysis of antibiotic resistance in Gram-negative enteric bacteria isolated from Pelophylax sp. in the Eastern Black Sea Region. The aim of this study was to evaluate the prevalence and types of antimicrobial resistance among Gram-negative enteric bacteria isolated from Pelophylax sp. Fifty-four frogs were collected from six provinces in the Eastern Black Sea Region of Turkey. In the cloacal swab cultures, bacteria from 160 different colonies were identified by biochemical tests, automated systems, and matrix-assisted laser desorption ionisation-time of flight mass spectrometry. The antimicrobial susceptibility tests were performed by the disk diffusion method. The observed drug resistance rate was the highest to ampicillin and cefazolin, while the lowest against ciprofloxacin and tetracycline. In the molecular assays, bla TEM (8 Citrobacter spp.), bla SHV (2 Escherichia coli, 1 Hafnia alvei, and a Serratia liquefaciens), tetA genes (E. coli and Klebsiella spp.) and a class 1 integron without any gene cassette (E. coli) were detected. Among the strains, no plasmid-mediated quinolone resistance [qnrA, qnrB, qnrS, qepA and aac (6 ')-Ib-cr] was found. However, two of three quinolone-resistant Klebsiella strains showed the novel amino acid substitution in the gyrA gene resulting in Ser83Asp and Asp87Glu.The clonality between E. coli isolates was also examined by pulsed-field gel electrophoresis. We consider that multidrug-resistant Gram-negative enteric bacteria in the intestinal microbiota of a cosmopolitan frog species might be a reservoir for antibiotic resistance genes. | 2021 | 34570716 |
| 1270 | 12 | 0.9984 | Multiantibiotic resistance of gram-negative bacteria isolated from drinking water samples in southwest Greece. In this study we monitored the sensitivity of 239 gram-negative bacteria (of fecal and non-fecal origin), isolated from the old drinking water distribution network of Patras in southwestern Greece, to 20 antibiotic agents. Two methods were used to find the multiresistant bacteria (bacteria resistant to two or more antibiotics): the diffusion disk method and a serial dilution method. The gram-negative bacteria tested were: Enterobacteriaceae (62), Pseudomonas (145), Vibrionaceae (24), Chromobacter (3), Acinetobacter (2) and others (4). The highest levels of antibiotic resistance were obtained for cephalothin (86.7%), ampicillin (77.5%) and carbenicillin (71%) followed by cefoxitin (55.4%) and cefuroxime (51.2%). Intermediate resistance levels were found for ticarcillin (31.3%), ceftizoxime (31.2%), chloramphenicol (30.3%), and cefotetan (25.2%). Low resistance levels were obtained for cefotaxime (17.9%), sulfisoxazole (15.2%), ceftriaxone (12.5%), tetracycline (11.9%), trimethoprim/sulfamethoxazole (7.4%) and piperacillin (2.4%). Overall 91.3% of the gram-negative bacteria isolated from drinking water were multiresistant. No resistant strains were found to quinolones, aminoglycosides, imipenem, aztreonam, ceftazidime or cefoperazone. The high antibiotic resistance rate of the isolated microorganisms from the Patras drinking water supply is discussed. | 2000 | 10949974 |
| 1106 | 13 | 0.9984 | Characteristics of ciprofloxacin-resistant Enterobacteriaceae isolates recovered from wastewater of an Algerian hospital. INTRODUCTION: Hospital effluents are a source of environmental pollution by drugs, antibiotic-resistant bacteria, and resistance genes. Quinolones, particularly ciprofloxacin, are commonly detected in these effluents, contributing to the emergence of antimicrobial resistance. The objective of this study was to characterize ciprofloxacin-resistant Enterobacteriaceae in hospital effluents. METHODOLOGY: Isolates were selected on Tergitol-7 agar supplemented with ciprofloxacin and genotyped by ERIC-PCR. Antibiotic susceptibility testing was done using the disk diffusion method, and minimum inhibitory concentrations were determined using the agar dilution method. Resistance genes, integrons, phylogenetic groups, and sequence types were identified by PCR and sequencing. RESULTS: A total of 17 ciprofloxacin-resistant isolates were characterized: Escherichia coli, Escherichia vulneris, Klebsiella pneumoniae, Klebsiella oxytoca, Citrobacter freundii, and Citrobacter koseri/farmeri. Isolates presented concomitant resistance to nalidixic acid, ciprofloxacin, ofloxacin, and pefloxacin. A diversity in mutation patterns in gyrA and parC genes and new amino-acid substitutions in GyrA subunit were observed. Quinolone plasmidic resistance genes qnrB1, qnrB2, qnrB5/19, qnrS1, and aac(6')-Ib-cr were detected. Resistance to other antibiotic classes was observed. Class 1 integrons and resistance genes blaCTX-M-15, blaOXA-1, sul1, sul2, sul3, tetA, tetB, aadA1/2, aadA5, aph(3')-Ia, aac(3)II, dfrA1, dfrA5, dfrA7, and dfrA12 were detected. Bacterial tolerance to cadmium, zinc, and mercury was observed with the presence of the merA gene. E. coli isolates belonged to phylogenetic groups A, B1, and D and to sequence types ST405, ST443, ST101, ST10, and ST347. CONCLUSIONS: This study highlighted bacterial multidrug resistance linked to ciprofloxacin and, consequently, the risk of bacterial exposure to this antibiotic. | 2016 | 27482804 |
| 1269 | 14 | 0.9984 | Prevalence of Resistance Genes Among Multidrug-Resistant Gram-Negative Bacteria Isolated from Waters of Rivers Swat and Kabul, Pakistan. The waters of rivers Swat and Kabul are the main water source for domestic and irrigation purposes in the northwestern part of Pakistan. However, this water has been contaminated due to human activities. This study aimed to analyze the water of these rivers for occurrence of antibiotic resistance genes among Gram-negative bacteria. Samples were collected from 10 different locations of these rivers. The samples were processed for the isolation of Gram-negative bacteria. Isolated bacteria were checked against 12 different antibiotics for susceptibility. The isolates were also analyzed for the presence of seven antibiotic resistance genes. A total of 50 bacterial isolates were recovered that belonged to five different bacterial genera, that is, Escherichia coli, Klebsiella oxytoca, Pseudomonas aeruginosa, Raoultella terrigena (Klebsiella terrigena), and Pseudomonas fluorescens. Antibiotic resistance pattern was cefixime 72%, cephalothin 72%, ampicillin 68%, nalidixic acid 68%, kanamycin 54%, streptomycin 42%, sulfamethoxazole-trimethoprim 28%, chloramphenicol 28%, meropenem 8%, gentamicin 8%, amikacin 2%, and tobramycin 2%. The prevalence of bla-TEM gene was 72% (n = 36), aadA gene 34% (n = 17), sul gene 32% (n = 16), bla-CTXM gene 12% (n = 6), int gene 66% (n = 33), and int1 gene 6% (n = 3). This information highlights the need for controlling and monitoring the release of domestic wastes to rivers. | 2025 | 39435695 |
| 1165 | 15 | 0.9984 | Isolation, Antimicrobial Susceptibility Profile and Detection of Sul1, blaTEM, and blaSHV in Amoxicillin-Clavulanate-Resistant Bacteria Isolated From Retail Sausages in Kampar, Malaysia. BACKGROUND: Due to the overuse of antibiotics in livestock as a growth-promoting agent, the emergence of multi-antibiotic resistant bacteria is becoming a concern. OBJECTIVES: In this study, we aimed to detect the presence and discover the molecular determinants of foodborne bacteria in retail sausages resistant towards the antibacterial agent amoxicillin-clavulanate. METHODS: Two grams of sausages were chopped into small pieces and transferred into sterile Luria-Bertani (LB) enrichment broths overnight before they were plated on MacConkey agar petri dishes. The bacteria isolated were then screened for amoxicillin-clavulanate resistance, and an antimicrobial susceptibility test of each isolate was performed by using the disc diffusion method. Double synergy and phenotypic tests were carried out to detect the presence of extended spectrum β-lactamase (ESBL). API 20E kit was used to identify the Enterobacteriaceae. All isolates were further examined by polymerase chain reaction (PCR) for resistant genes blaOXA-1, blaOXA-10, plasmid-mediated AmpC (blaCMY and blaDHA), and the chromosome-mediated AmpC, Sul1, blaTEM, and blaSHV genes. RESULTS: A total of 18 amoxicillin-clavulanate resistant isolates were obtained from seven different types of retail sausages. Only half of them were identified as Enterobacteriaceae, but none were ESBL-producers. All the 18 isolated strains demonstrated resistance towards amoxicillin-clavulanate, penicillin and oxacillin (100%), cefotaxime (71.4%), cefpodoxime (66.7%), and ampicillin (83.3%). blaTEM was the most frequently detected β-lactamase gene. Both plasmid- and chromosomal-bound blaTEM genes were detected in all of the isolated Enterobacteriaceae. blaSHV and Sul1 accounted for 22.2% and 11.1% of the amoxicillin-clavulanate resistant isolates, respectively, whereas blaAMPC, blaCMY, blaDHA, blaOXA-1, and blaOXA-10 were not found in any of the isolates. The only one ESBL-producing bacteria detected in this study was Chryseobacterium meningosepticum, which harbored the blaTEM gene. CONCLUSIONS: The multidrug resistant bacteria that carry antibiotic resistant genes from retail sausages may increase the risk of transmission to humans via the consumption of contaminated sausages. Stricter measures must be taken to address the use of antibiotics in animal agriculture and to consider their potential impact on human health. | 2016 | 27942365 |
| 2711 | 16 | 0.9984 | Antibiotic-resistant Escherichia coli and Salmonella spp. associated with dairy cattle and farm environment having public health significance. AIM: The present study was carried out to determine load of total bacteria, Escherichia coli and Salmonella spp. in dairy farm and its environmental components. In addition, the antibiogram profile of the isolated bacteria having public health impact was also determined along with identification of virulence and resistance genes by polymerase chain reaction (PCR) under a one-health approach. MATERIALS AND METHODS: A total of 240 samples of six types (cow dung - 15, milk - 10, milkers' hand wash - 10, soil - 10 water - 5, and vegetables - 10) were collected from four dairy farms. For enumeration, the samples were cultured onto plate count agar, eosin methylene blue, and xylose-lysine deoxycholate agar and the isolation and identification of the E. coli and Salmonella spp. were performed based on morphology, cultural, staining, and biochemical properties followed by PCR.The pathogenic strains of E. coli stx1, stx2, and rfbO157 were also identified through PCR. The isolates were subjected to antimicrobial susceptibility test against 12 commonly used antibiotics by disk diffusion method. Detection of antibiotic resistance genes ereA, tetA, tetB, and SHV were performed by PCR. RESULTS: The mean total bacterial count, E. coli and Salmonella spp. count in the samples ranged from 4.54±0.05 to 8.65±0.06, 3.62±0.07 to 7.04±0.48, and 2.52±0.08 to 5.87±0.05 log colony-forming unit/g or ml, respectively. Out of 240 samples, 180 (75%) isolates of E. coli and 136 (56.67%) isolates of Salmonella spp. were recovered through cultural and molecular tests. Among the 180 E. coli isolates, 47 (26.11%) were found positive for the presence of all the three virulent genes, of which stx1 was the most prevalent (13.33%). Only three isolates were identified as enterohemorrhagic E. coli. Antibiotic sensitivity test revealed that both E. coli and Salmonella spp. were found highly resistant to azithromycin, tetracycline, erythromycin, oxytetracycline, and ertapenem and susceptible to gentamycin, ciprofloxacin, and imipenem. Among the four antibiotic resistance genes, the most observable was tetA (80.51-84.74%) in E. coli and Salmonella spp. and SHV genes were the lowest one (22.06-25%). CONCLUSION: Dairy farm and their environmental components carry antibiotic-resistant pathogenic E. coli and Salmonella spp. that are potential threat for human health which requires a one-health approach to combat the threat. | 2019 | 31528022 |
| 1024 | 17 | 0.9984 | Phenotypic and genotypic characteristics of beta-lactamase dominant with CARBA, AmpC, and ESBL-producing bacteria in municipal wastewater influent in Helsinki, Finland. OBJECTIVES: Analysing samples of municipal wastewater influent (before treatment) can help to map the status of antibiotic-resistant bacteria (ARB) at the population level in sewershed communities and may also help in predicting the public health risks of ARB in surface water because of the outfall of wastewater. In this study, we investigated the bacterial isolates carrying beta-lactamase genes in wastewater and compared their genotypic and phenotypic characteristics. METHODS: A total of 399 bacterial isolates grown on CHROMagarESBL (n = 207) and CHROMagarKPC (n = 192) from composite wastewater influent samples (n = 7) from the Viikinmäki wastewater treatment plant (Helsinki) were subcultured, nucleic acid was extracted, and the prevalence of different beta-lactamase genes was screened with multiplex polymerase chain reaction (PCR). All PCR-positive isolates were identified with MALDI-TOF. RESULTS: A total of 32.6% of isolates (130 of 399) were PCR positive for at least one resistance gene, and 13% of these positive isolates out of 130 had at least three resistance genes. Among the 22 detected genes, bla(GES group) was the most prevalent, at 25.8% (n = 198; many isolates carried multiple genes), followed by bla(MOX) (13.1%) and bla(TEM) (10.1%) as most frequently detected. Furthermore, out of 18 different bacterial species/genera detected as carrying beta-lactamase genes, A. hydrophila/caviae (28.5%), Enterobacter spp. (16.9%), and E. coli (14.6%) were the most prevalent. Enterobacter spp., Aeromonas spp., and K. cryocescens potentially carried AmpC genes, and E. coli carried ESBL genes. CONCLUSION: We recorded a huge variety of beta-lactamases (bla(Amp)(C), bla(ESBL), and bla(CARBA)) genes in many potential pathogens that probably originated from both enteric and environmental sources. | 2023 | 37169125 |
| 1115 | 18 | 0.9984 | 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 |
| 2698 | 19 | 0.9983 | EHEC, EPEC, and ETEC strains and their antibiotic resistance in drinking and tap water samples. BACKGROUND: Investigating of the presence of Enterohemorrhagic E. coli (EHEC), Enterotoxigenic E. coli (ETEC), Enteropathogenic E. coli (EPEC) strains and their antibiotic resistance in natural spring waters and tap waters from two university hospitals, in Istanbul. METHODS: E. coli strains isolated from water samples were identified by polymerase chain reaction (PCR) method using stx-1, stx-2, eaeA genes specific for EHEC; eaeA, bfp genes specific for EPEC and lt, st genes specific for ETEC. Antibiotic susceptibility tests were done according to the Kirby-Bauer method using The Clinical and Laboratory Standards Institute (CLSI) criteria. RESULTS: E. coli strains were isolated from only five (2.7%) out of 184 water samples. Only one of the 36 E. coli strains isolated from these five water samples was found to be extended spectrum beta lactamase (ESBL) positive. According to PCR, ten E. coli strains isolated from one drinking water were identified as ETEC. Other than E. coli strains, coliforms and non-fermentative Gram negative bacteria were also isolated from waters. It was shown that 60 (81.1%) of these 74 strains isolated, other than E. coli, were found to be multiple resistant. CONCLUSIONS: Contrary to our expectations, it has been shown that natural spring waters (drinking waters) can be much more contaminated with fecal bacteria when compared with tap waters. The presence of pathogenic E. coli strains and antibiotic resistant Gram negative bacteria especially in drinking waters emphasize the importance of these types of studies. | 2015 | 25807645 |