# | Rank | Similarity | Title + Abs. | Year | PMID |
|---|---|---|---|---|---|
| 0 | 1 | 2 | 3 | 4 | 5 |
| 2667 | 0 | 1.0000 | Prevalence, virulence and antimicrobial resistance patterns of Aeromonas spp. isolated from children with diarrhea. BACKGROUND: Aeromonas spp. cause various intestinal and extraintestinal diseases. These bacteria are usually isolated from fecal samples, especially in children under five years old. The aim of this study was to assess the prevalence of Aeromonas spp. and their antimicrobial resistance profile in children with diarrhea referred to the Children Medical Center in Tehran, between 2013 and 2014. METHODS: A total number of 391 stool samples were collected from children with ages between 1 day and 14 years old, with diarrhea (acute or chronic), referred to the Children Hospital, Tehran, Iran, between 2013 and 2014. Samples were enriched in alkaline peptone water broth for 24 hours at 37 °C and then cultured. Suspicious colonies were analyzed through biochemical tests. Furthermore, antimicrobial susceptibility tests were carried out for the isolates. Isolates were further studied for act, ast, alt, aerA and hlyA virulence genes using polymerase chain reaction. RESULTS: In total, 12 isolates (3.1%) were identified as Aeromonas spp.; all were confirmed using the API-20E test. Of these isolates, five A. caviae (42%), four A. veronii (33%) and three A. hydrophila (25%) were identified in cases with gastroenteritis. Second to ampicillin (which was included in the growth medium used), the highest rate of antimicrobial resistance was seen against nalidixic acid and trimethoprim-sulfamethoxazole (5 isolates each, 41.6%) and the lowest rate of antimicrobial resistance was seen against gentamicin, amikacin and cefepime (none of the isolates). Results included 76.4% act, 64.7% ast, 71.5% alt, 83.3% aerA and 11.7% hlyA genes. CONCLUSION: Aeromonas spp. are important due to their role in diarrhea in children; therefore, isolation and identification of these fecal pathogens should seriously be considered in medical laboratories. Since virulence genes play a significant role in gastroenteritis symptoms caused by these bacteria, Aeromonas species that include virulence genes are potentially suspected to cause severe infections. Moreover, bacterial antimicrobial resistance is increasing, especially against trimethoprim-sulfamethoxazole and nalidixic acid. | 2016 | 27622161 |
| 2668 | 1 | 0.9999 | Genotyping and distribution of putative virulence factors and antibiotic resistance genes of Acinetobacter baumannii strains isolated from raw meat. BACKGROUND: Acinetobacter baumannii strains with multiple antimicrobial resistance are primarily known as opportunistic nosocomial bacteria but they may also be regarded as emerging bacterial contaminants of food samples of animal origin. Here we aimed to study the molecular characteristics of the A. baumanni strains isolated from raw meat samples. METHODS: A total of 22 A. baumanni strains were isolated from 126 animal meat samples and were genotyped by ERIC-PCR method and by PCR detection of their virulence and antimicrobial resistance determinants. A. baumannii strains with 80% and more similarities were considered as one cluster. RESULTS: Sixteen different genetic clusters were found amongst the 22 A. baumanni strains. Of the 22 strains, 12 (54.54%) had similar genetic cluster. A. baumannii strains exhibited the highest percentage of resistance against tetracycline (90.90%), trimethoprim (59.09%), cotrimoxazole (54.54%) and gentamicin (50.00%). TetA (81.81%), tetB (72.72%), dfrA1 (63.63%), aac(3)-IV (63.63%), sul1 (63.63%) and aadA1 (45.45%) were the most commonly detected antibiotic resistance genes. FimH (81.81%), afa/draBC (63.63%), csgA (63.63%), cnf1 (59.09%), cnf2 (54.54%) and iutA (50.00%) were the most commonly detected virulence factors. A. baumannii strains isolated from the chicken meat samples had the highest similarities in the genetic cluster. CONCLUSIONS: A. baumannii strains with similar genetic cluster (ERIC-Type) had the same prevalence of antibiotic resistance, antibiotic resistance genes and virulence factors. Genetic cluster of the A. baumannii strains is the main factor affected the similarities in the genotypic and phenotypic properties of the A. baumannii strains. | 2018 | 30323923 |
| 2974 | 2 | 0.9999 | Diversity of Virulence Genes in Multidrug Resistant Escherichia coli from a Hospital in Western China. BACKGROUND: Escherichia coli strains are the most commonly isolated bacteria in hospitals. The normally harmless commensal E. coli can become a highly adapted pathogen, capable of causing various diseases both in healthy and immunocompromised individuals, by acquiring a combination of mobile genetic elements. Our aim was to characterize E. coli strains from a hospital in western China to determine their virulence and antimicrobial resistance potential. METHODS: A total of 97 E. coli clinical isolates were collected from the First Affiliated Hospital of Chengdu Medical College from 2015 to 2016. Microbiological methods, PCR, and antimicrobial susceptibility tests were used in this study. RESULTS: The frequency of occurrence of the virulence genes fimC, irp2, fimH, fyuA, lpfA, hlyA, sat, and cnf1 in the E. coli isolates was 93.81, 92.78, 91.75, 84.54, 41.24, 32.99, 28.86, and 7.22%, respectively. Ninety-five (97.9%) isolates carried two or more different virulence genes. Of these, 44 (45.4%) isolates simultaneously harbored five virulence genes, 24 (24.7%) isolates harbored four virulence genes, and 17 (17.5%) isolates harbored six virulence genes. In addition, all E. coli isolates were multidrug resistant and had a high degree of antimicrobial resistance. CONCLUSION: These results indicate a high frequency of occurrence and heterogeneity of virulence gene profiles among clinical multidrug resistant E. coli isolates. Therefore, appropriate surveillance and control measures are essential to prevent the further spread of these isolates in hospitals. | 2019 | 31824179 |
| 2154 | 3 | 0.9999 | Molecular analysis of multidrug-resistant E. coli in pediatric UTIs: findings from a Nigerian Hospital. INTRODUCTION: This study aimed to isolate and characterize antibiotic-resistant Escherichia coli from urine samples of children at the Mother and Child Hospital in Ondo State, Nigeria, assessing antibiogram profiling and resistance genes. METHODOLOGY: Three hundred urine samples (158 females, 142 males), aged 3-5 years, were collected, transported on ice, and analyzed bacteriologically. E. coli and Gram-negative bacteria were isolated using Eosin Methylene Blue agar and identified through colony morphology and biochemical tests. Antibiotic susceptibility was determined via Kirby Bauer's disc diffusion, and resistance genes were detected using Polymerase Chain Reaction (PCR). RESULTS: Of the 300 samples, 40 (13.3%) yielded E. coli with varying antibiotic resistance profiles. The highest resistance was against Amoxicillin-clavulanate (87.5%) followed by Ceftriaxone (80%). Susceptibility was observed to Nitrofurantoin, Erythromycin, and Chloramphenicol. Multiple resistance patterns against 3-4 antibiotic classes were recorded, with 12 distinct patterns observed. Eight isolates harbored blaCTX-M gene, while five carried the aac3-IV gene. CONCLUSIONS: The study concluded a high occurrence of E. coli infection and multiple antibiotic resistance in the region. The presence of resistance genes suggests significant economic and health implications, emphasizing prudent antibiotic use under physician guidance to mitigate multiple antibiotic resistance. | 2024 | 38484349 |
| 2709 | 4 | 0.9999 | Isolation, genotyping and antibiotic resistance analysis in Salmonella species isolated from turkey meat in Isfahan, Iran. Salmonella is one of the mainzoonotic bacteria in the poultry industry.The knowledge about biological characteristics and antibiotic resistance pattern can help medication in poultry and human. This research aimed to study Salmonella spp contamination and its antibiotic resistance in turkey meat in Isfahan province, Iran.400 samples were collected from the turkey meat in slaughter line (May 2021 to May 2022). The conventional microbiological and biochemical tests were applied for isolation and typing of Salmonella spp. The polymerase chain reaction (PCR) was utilized for detection and typing of Salmonella strains. The antibiotic sensitivity test was achieved and all strains were evaluated for resistance genes of Act (3)-IV, Sul1 and qnrA. In microbiological examination, 32 Salmonella strains (8 %) were identified. All tested strains were positive for invA gene. By amplifying the FlicC and Prot6E genes, 28 and 4 strains had genes related to enteritidis and typhimurium, respectively. In disc diffusion test, the highest antibiotic resistance was to oxytetracycline (50 %) and the lowest was to gentamicin, amoxiclavulanic acid, cefotaxime and ceftriaxone. The results showed that 6 (18.75 %) and 10 (31.25 %) of the Salmonella spp were able to amplify Sul1 and qnrA genes, respectively. No Salmonella strain could amplify Act (3)-IV gene. 100 % of the strains carried the Sul1 and qnrA genes were resistant to sulfonamide, and enrofloxacin. Furthermore, 3 sulfonamide resistant strains (75 %) and 5 enrofloxacin resistant strains (83.33 %) were harbored Sul1 and qnrA genes, respectively. The prevalence and antibiotic resistance of Salmonella spp in turkey meat can induce health risk concern. However, the wide spectrum antibiotic resistance complicates the proper treatment of Salmonella infection in human. | 2025 | 39944349 |
| 2152 | 5 | 0.9999 | Immunological and molecular detection of biofilm formation and antibiotic resistance genes of Pseudomonas aeruginosa isolated from urinary tract. BACKGROUND AND OBJECTIVES: Pseudomonas aeruginosa (P. aeruginosa) is one of the most common causes of hospital-acquired infections. It is associated with high morbidity and healthcare costs, especially when appropriate antibiotic treatment is delayed. Antibiotic selection for patients with P. aeruginosa infections is challenging due to the bacteria's inherent resistance to many commercially available antibiotics. This study investigated antibiotic-resistance genes in isolated bacteria, which play a key role in disease pathogenesis. MATERIALS AND METHODS: 100 samples out of the 140 samples collected from urinary tract infections (UTIs) cases between December 15(th), 2022, and April 15(th), 2023, were included in the study. Identification of bacterial isolates was based on colony morphology, microscopic examination, biochemical tests, and the Vitek-2 system. Antibiotic resistance genes; Aph(3)-llla, ParC, Tet/tet(M), and aac(6´)-Ib-cr were tested by polymerase chain reaction (PCR). RESULTS: The obtained results were based on bacterial identifications of 81 clinical samples. Only 26 (32%) of these isolates were P. aeruginosa, 21 (26%) were Escherichia coli, and 18 (22.2%) were other bacteria. These isolates were used to detect four genes including tet(M), Aph(3)-llla, Par-c, and aac(6´)-Ib-cr. Four types of primers were used for PCR detection. The results showed that 11/14 (78.57%) carried the tet(M) gene, 10/14 (71.42%) carried the Aph(3)-llla gene, 14/14 (100%) carried the Par-c gene, and 10/14 (71.42%) of the isolates carried the aac(6´)-Ib-cr gene. The biofilm formation examining the esp gene, showed that 9 (64.28) isolates carried this gene. CONCLUSION: The inability of antibiotics to penetrate biofilms is an important factor contributing to the antibiotic tolerance of bacterial biofilms. | 2025 | 40612720 |
| 2151 | 6 | 0.9999 | Study of the Genomic Characterization of Antibiotic-Resistant Escherichia Coli Isolated From Iraqi Patients with Urinary Tract Infections. Urinary tract infection is one of the last diseases prevalent in humans, with various causative agents affecting 250 million people annually, This study analyzed UTIs in Iraqi patients caused by Escherichia coli. ESBL enzymes contribute to antibiotic resistance. The research aimed to analyze ESBL gene frequency, resistance patterns, and genetic diversity of E. coli strains; Between Dec 2020 and May 2021, 200 urine samples were collected, cultured on blood agar, EMB, and MacConkey's plates, samples incubated at 37 °C for 24 h. Positive samples (> 100 cfu/ml) underwent Kirby-Bauer and CLSI antibiotic susceptibility testing. PCR detected virulence genes, Beta-lactamase coding genes, and biofilm-associated resistance genes in E. coli isolates; Out of 200 isolates, 80% comprised Gram-positive and Gram-negative bacteria. Specifically, 120 isolates (60%) were Gram-negative, while 40 isolates (20%) were Gram-positive. Among Gram-negative isolates, 20% were identified as E. coli. Remarkably, all E. coli strains showed resistance to all tested antibiotics, ranging from 80 to 95% resistance. The E. coli isolates harbored three identified resistance genes: blaTEM, blaSHV, and blaCTXM. Regarding biofilm production, 10% showed no formation, 12% weak formation, 62% moderate formation, and 16% strong formation; our study found that pathogenic E. coli caused 20% of UTIs. The majority of studied E. coli strains from UTI patients carried the identified virulence genes, which are vital for infection development and persistence. | 2024 | 39011020 |
| 2155 | 7 | 0.9998 | Resistance Profiles and Virulence Factors of Enteric Escherichia coli in Chronic Kidney Disease Patients at Laquintinie Hospital in Douala, Cameroon. Escherichia coli is commonly found in human feces and is the most prevalent resistant microorganism in patients with chronic kidney disease. Several studies demonstrated that virulence factors were a major cause of the emergence of pathogenic strains of E. coli. This study's objective was to determine the antibiotic resistance profile, detect virulence factors, and assess the prevalence of carriage of extended-spectrum beta-lactamase (ESBL) genes in fecal E. coli isolates obtained from chronic kidney disease patients. This research was carried out in Laquintinie Hospital of Douala between January 2022 and December 2023. In total, 458 patients with (n = 197) or without (n = 261) chronic kidney disease and suffering from gastroenteritis constituted the total population. E. coli isolates were obtained by using eosin methylene blue (EMB) agar and identified by the API 20E gallery system. The Kirby-Bauer method was used to determine the isolates' antibiotic resistance profile. The simplex polymerase chain reaction (PCR) served to detect virulence factors and resistance genes. It appeared that all antibiotics tested, except nalidixic acid, presented a significant resistance (p < 0.05) in chronic kidney disease patients contrasted to patients without chronic kidney disease. The antibiotic susceptibility testing revealed a high level of resistance to amoxicillin (94.5%), amoxicillin-clavulanic acid (79.5%), trimethoprim/sulfamethoxazole (69.9%), and ofloxacin (65.8%) in patients with chronic kidney disease. E. coli isolates showed (p < 0.001) a significantly high rate of multidrug resistance phenotype in chronic kidney disease patients (74.0%) as compared to patients without chronic kidney disease (35.7%). According to the virulence genes detected, the most prevalent pathotype of E. coli was the enteropathogenic E. coli (40.8%; n = 40), followed by enterotoxigenic E. coli (29.6%; n = 29) and shiga toxin-producing E. coli (29.6%; n = 29). The screening of resistance genes in pathotypes of E. coli has demonstrated that bla (TEM) (76.5%; n = 75) and bla (CTX-M) (75.5%; n = 74) were the more frequent ESBL resistance genes encountered. This study showed that a high rate of resistance, multidrug resistance, and a high frequency of enteropathogenic E. coli and ESBL resistance genes in E. coli were most often found in chronic kidney disease patients. This high level of enteric multidrug-resistant E. coli in chronic kidney disease patients exposes them to hazardous antibiotic treatment and serious public health issues. | 2025 | 40980185 |
| 2972 | 8 | 0.9998 | Genetic characterisation of class 1 integrons among multidrug-resistant Salmonella serotypes in broiler chicken farms. OBJECTIVES: Antimicrobial resistance in Salmonella serotypes has been reported. Integrons play an important role in the dissemination of antimicrobial resistance genes in bacteria. Scarce literature is available on the identification of integrons in Salmonella isolated from broiler chickens. In this study, antimicrobial susceptibility testing and characterisation of class 1 integrons among multidrug-resistant (MDR) Salmonella enterica serotypes in broiler chicken farms in Egypt were performed. METHODS: Antimicrobial susceptibility was determined by the disk diffusion method. PCR was performed to detect antimicrobial resistance genes and class 1 integrons in the tested Salmonella serotypes. Gene sequencing of the variable region of a class 1 integron was performed. RESULTS: Salmonella spp. were detected in 26 (13.5%) of 192 broiler samples, with Salmonella Enteritidis being the most frequently detected serotype, followed by Salmonella Kentucky and Salmonella Typhimurium and other serotypes. A very high resistance rate was observed to trimethoprim/sulfamethoxazole (100%), whilst a low resistance rate was observed to cefuroxime (57.7%). MDR S. enterica isolates displayed resistance to ciprofloxacin and azithromycin. Class 1 integrons were detected in 20 (76.9%) of the 26 Salmonella isolates. A high prevalence of class 1 integrons, as the first recorded percentage in the literature, associated with MDR Salmonella isolates was observed. CONCLUSIONS: Antimicrobial resistance rates in Salmonella serotypes from broiler chicken farms were alarming, especially for ciprofloxacin and azithromycin. Thus, another therapeutic strategy other than antimicrobials is recommended to prevent outbreaks of MDR Salmonella. | 2018 | 29684574 |
| 1130 | 9 | 0.9998 | The characteristic of antibiotic drug resistance of Salmonella Typhi isolated from tertiary care hospital in Faisalabad. Salmonella Typhi, a human-restricted pathogen, is demonstrating multi-drug resistance (MDR) due to widespread and inappropriate antibiotic use. This study aims to molecular identify the pattern of antibiotic resistance. Blood samples from 2456 suspected patients were assessed. Molecular identification of Salmonella Typhi was performed by amplifying the fliC gene. The Disc diffusion method was used to measure the susceptibility of antibiotics. 2456 patient samples, bacterial growth and Salmonella Typhi were 152 (6.2 %) positive. PCR analysis confirmed that all 152 isolated strains were Salmonella Typhi (100%) through the amplification of the fliC gene. Salmonella Typhi isolates showed resistance to trimethoprim (58%), ampicillin (63%), ciprofloxacin (79%) and chloramphenicol (58%). Fifty-eight percent of the isolates showed multi-drug resistance, whereas 26 percent had extensive drug resistance. Antibiotic resistance gene of quinolones was isolated as 44 (36.4%), whereas 88 (57.9 %) were positive for bla(CTX-M) gene were detected among cephalosporin-resistance bacteria 56 (36.8 %) resistance bla(IMP) and bla(OXA-48) were detected among carbapenem-resistance bacteria. For the azithromycin resistance, more genes were detected as a percentage 03 (50 %) from isolates. It concludes that several multidrug resistance and extensive drug-resistance Salmonella Typhi were found. The majority of isolates were sensitive to meropenem, Imipenem and Azithromycin. | 2025 | 40996203 |
| 2666 | 10 | 0.9998 | The Characteristics of Multilocus Sequence Typing, Virulence Genes and Drug Resistance of Klebsiella pneumoniae Isolated from Cattle in Northern Jiangsu, China. Klebsiella pneumoniae (K. pneumoniae) induced bovine mastitis has been becoming one of the dominantly pathogenic bacteria in cases of bovine mastitis, and is threatening public health through dairy products. In order to explore the characteristics of multilocus sequence typing (MLST), virulence gene carrying, and the relationship between virulence genes and the antibiotic resistance of Klebsiella pneumoniae from dairy cattle in northern Jiangsu, 208 dairy milk samples were collected from four dairy farms in northern Jiangsu. A total of 68 isolates were obtained through bacterial isolation, purification, and 16S rDNA identification. Eleven virulence genes were detected by specific PCR. The susceptibility of the isolates to antimicrobials was analyzed using the Kirby-Bauer method. The Pearson correlation coefficient was used to analyze the correlation between the presence of virulence genes and the phenotype of drug resistance. ST 2661 was the most prevalent type of K. pneumoniae (13/68, 19.1%) among the 23 ST types identified from the 68 isolates. The virulence gene allS was not detected, but the positive detection rates of the virulence genes fimH, ureA, uge and wabG were 100.0%. Notably, the detection rates of genes rmpA and wcaG, related to the capsular polysaccharide, were 4.4% and 11.8%, respectively, which were lower than those of genes related to siderophores (kfuBC, ybtA and iucB at 50.0%, 23.5%, and 52.9%, respectively). The K. pneumoniae isolates were sensitive to ciprofloxacin, nitrofurantoin, and meropenem. However, the resistance rate to penicillin was the highest (58/68, 85.3%), along with resistance to amoxicillin (16/68, 23.5%). The results revealed the distribution of 23 ST types of K. pneumoniae from the milk from bovine-mastitis-infected dairy cows in northern Jiangsu, and the expression or absence of the virulence gene kfuBC was related to the sensitivity to antibiotics. The current study provides important information relating to the distribution and characteristics of K. pneumoniae isolated from dairy cows with clinical bovine mastitis, and is indicative of strategies for improving the treatment of K. pneumoniae-induced bovine mastitis. | 2022 | 36230368 |
| 2681 | 11 | 0.9998 | Determination of the Prevalence and Antimicrobial Resistance of Enterococcus faecalis and Enterococcus faecium Associated with Poultry in Four Districts in Zambia. The presence of antimicrobial-resistant Enterococci in poultry is a growing public health concern worldwide due to its potential for transmission to humans. The aim of this study was to determine the prevalence and patterns of antimicrobial resistance and to detect drug-resistant genes in Enterococcus faecalis and E. faecium in poultry from four districts in Zambia. Identification of Enterococci was conducted using phenotypic methods. Antimicrobial resistance was determined using the disc diffusion method and antimicrobial resistance genes were detected using polymerase chain reaction and gene-specific primers. The overall prevalence of Enterococci was 31.1% (153/492, 95% CI: 27.1-35.4). Enterococcus faecalis had a significantly higher prevalence at 37.9% (58/153, 95% CI: 30.3-46.1) compared with E. faecium, which had a prevalence of 10.5% (16/153, 95% CI: 6.3-16.7). Most of the E. faecalis and E. faecium isolates were resistant to tetracycline (66/74, 89.2%) and ampicillin and erythromycin (51/74, 68.9%). The majority of isolates were susceptible to vancomycin (72/74, 97.3%). The results show that poultry are a potential source of multidrug-resistant E. faecalis and E. faecium strains, which can be transmitted to humans. Resistance genes in the Enterococcus species can also be transmitted to pathogenic bacteria if they colonize the same poultry, thus threatening the safety of poultry production, leading to significant public health concerns. | 2023 | 37107019 |
| 2711 | 12 | 0.9998 | 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 |
| 1166 | 13 | 0.9998 | Yearly incidence of acute childhood gastroenteritis in Nigeria: Implicated pathogens predominantly harbor blaCTXM and blaTEM genes. BACKGROUND AND OBJECTIVES: Routine use of antibiotics for infectious diarrhea in children is associated with the risk of increasing antibiotic resistance in developing countries. This work aimed to study the predominant extended spectrum beta-lactamase (ESBL) genes among bacteria pathogens implicated in acute childhood gastroenteritis in a tertiary hospital in Nigeria. MATERIALS AND METHODS: The stool samples of children diagnosed with acute gastroenteritis were collected. Isolation and identification of bacterial pathogens from the stool samples using standard microbiological and molecular sequencing methods. Pure cultures of the probable bacteria pathogens were subjected to antibiotics susceptibility profiling using the Kirby-Bauer Disk Diffusion Method and also screened for ESBL and AmpC using the Modified Double Disc Synergy Test. Primers for 5 different ESBL genes associated with beta-lactam antibiotic resistance were amplified and sequenced. RESULTS: Out of the 62 isolates, the highest number of organisms identified within the isolates were Bacillus sp at 38.7% (24) followed by Alcaligenes sp at 37% (23). Resistance to cefepime and ceftazidime were recorded at 50.8% (30) each. Ceftriaxone and cefotaxime were resisted in 47.4% (28) of the isolates. Out of 34 isolates resistant to all the cephalosporins used, 41.2% (14) were ESBL-producing, of which blaCTXM-1 and blaCTXM-2 were detected in 85.7%, while blaTEM was seen in 64.3%. CONCLUSIONS: blaCTXM and blaTEM may be the predominant ESBL genes haboured in the bacteria pathogens implicated in the yearly incidence of acute childhood gastroenteritis in Nigeria. This may be due to the widespread use of antibiotics in treating this disease. | 2025 | 39977466 |
| 2138 | 14 | 0.9998 | Isolation and molecular identification of multidrug-resistant Escherichia coli strains isolated from mastitic cows in Egypt. BACKGROUND: Mastitis is a common disease that affects the dairy sector globally because it not only impacts animal welfare but can also lead to significant financial losses. AIM: This study examined the phenotypic and genotypic profiles of the multidrug-resistant (MDR) Escherichia coli (E. coli) strains that were isolated from mastitic cows in Egypt to detect their pattern of antibiotic resistance. METHODS: Four hundred native breed lactating cows were evaluated to identify clinical and subclinical mastitis. A total of 100 mastitic milk samples (64 from clinical mastitis and 36 from subclinical mastitis) were collected for phenotypic isolation and identification of coliform bacteria. Escherichia coli isolates were identified through their morphological features, Gram staining, and biochemical tests. The identified E. coli strains were examined against various antibiotics using disk diffusion methods. All E. coli strains were analyzed for the antibiotic resistance genes Streptomycin (aadA), blaTEM, Tetracycline (tetA), Sulfonamides, and qnrA using PCR. RESULTS: Among 400 examined dairy cows, the prevalences of clinical and subclinical mastitis were 16% and 9%, respectively. Bacteriological isolation of coliform bacteria from mastitic milk samples revealed that E. coli was the most prevalent bacterium. Among 10 isolates of biochemically verified E. coli strains, 8 (80%) were MDR across 6 distinct classes of antibiotics. All recovered E. coli strains exhibited higher resistance to Amoxicillin, Cefotaxime, Sulphamethaxzole/Trimethoprim, and Tetracycline. High susceptibility was noticed to Ciprofloxaccin, Amoxicillin+Clavulinic, Streptomycin, Gentamicin, Chloramphenicol, and Colistin. The blaTEM gene was among the most common antibiotic resistance genes found in E. coli isolates (100%). Furthermore, the genotypes encoding resistance to tetA, aadA, and Sulfonamides were 50%, 40%, and 50%, respectively. CONCLUSION: MDR pathogenic E. coli strains are common in mastitic dairy cows in Egypt, and preventive actions must be implemented to avoid serious public health concerns. | 2025 | 40557079 |
| 2137 | 15 | 0.9998 | High prevalence of antibiotic resistance and biofilm formation in Salmonella Gallinarum. BACKGROUND AND OBJECTIVES: Antibiotic resistance is an indicator of the passively acquired and circulating resistance genes. Salmonella Gallinarum significantly affects the poultry food industry. The present study is the first study of the S. Gallinarum biofilm in Iran, which is focused on the characterization of the S. Gallinarum serovars and their acquired antibiotic resistance genes circulating in poultry fields in central and northwestern Iran. MATERIALS AND METHODS: Sixty isolates of S. Gallinarum serovar were collected from feces of live poultry. The bacteria were isolated using biochemical tests and confirmed by Multiplex PCR. Biofilm formation ability and the antibacterial resistance were evaluated using both phenotypic and genotypic methods. The data were analyzed using SPSS software. RESULTS: According to Multiplex PCR for ratA, SteB, and rhs genes, all 60 S. Gallinarum serovars were Gallinarum biovars. In our study, the antibiotic resistance rate among isolated strains was as follows: Penicillin (100%), nitrofurantoin (80%), nalidixic acid (45%), cefoxitin (35%), neomycin sulfate (30%), chloramphenicol (20%), and ciprofloxacin (5%). All isolates were susceptible to imipenem, ertapenem, ceftriaxone, ceftazidime, and ceftazidime+clavulanic acid. All sixty isolates did not express the resistance genes IMP, VIM, NDM, DHA, bla(OXA48), and qnrA. On the other hand, they expressed GES (85%), qnrB (75%), Fox M (70%), SHV (60%), CITM (20%), KPC (15%), FOX (10%), MOXM (5%), and qnrS (5%). All S. Gallinarum isolates formed biofilm and expressed sdiA gene. CONCLUSION: Considering that the presence of this bacteria is equal to the death penalty to the herd, the distribution of resistance genes could be a critical alarm for pathogen monitoring programs in the region. This study showed a positive correlation between biofilm formation and 50% of tested resistance genes. Also, it was found that the most common circulating S. gallinarum biovars are multidrug-resistant. | 2023 | 37941876 |
| 1288 | 16 | 0.9998 | Assessment of virulence factors and antimicrobial resistance among the Pseudomonas aeruginosa strains isolated from animal meat and carcass samples. BACKGROUND: Pseudomonas aeruginosa bacteria are emerging causes of food spoilage and foodborne diseases. Raw meat of animal species may consider a reservoir of P. aeruginosa strains. OBJECTIVES: The present survey was done to assess the prevalence, antibiotic resistance properties and distribution of virulence factors among the P. aeruginosa strains isolated from raw meat and carcass surface swab samples of animal species. METHODS: Five hundred and fifty raw meat and carcass surface swab samples were collected from cattle and sheep species referred to as slaughterhouses. P. aeruginosa bacteria were identified using culture and biochemical tests. The pattern of antibiotic resistance was determined by disk diffusion. The distribution of virulence and antibiotic resistance genes was determined using polymerase chain reaction. RESULTS: Forty-seven of 550 (8.54%) examined samples were contaminated with P. aeruginosa. The prevalence of P. aeruginosa in raw meat and carcass surface swab samples were 6.57 and 12%, respectively. P. aeruginosa isolates showed the maximum resistance rate toward penicillin (87.23%), ampicillin (85.10%), tetracycline (85.10%), gentamicin (65.95%) and trimethoprim (57.44%). The most commonly detected antibiotic resistance genes were BlaCTX-M (53.19%), blaDHA (42.55%) and blaTEM (27.65%). The most commonly detected virulence factors was ExoS (42.55%), algD (31.91%), lasA (31.91%), plcH (31.91%) and exoU (25.53%). CONCLUSIONS: Meat and carcass surface swab samples may be sources of resistant and virulent P. aeruginosa, which pose a hygienic threat in their consumption. However, further investigations are required to identify additional epidemiological features of P. aeruginosa in meat and carcass surface samples. | 2023 | 36418165 |
| 2973 | 17 | 0.9998 | An evaluation of multidrug-resistant Escherichia coli isolates in urinary tract infections from Aguascalientes, Mexico: cross-sectional study. BACKGROUND: Uropathogenic Escherichia coli (UPEC) are one of the main bacteria causing urinary tract infections (UTIs). The rates of UPEC with high resistance towards antibiotics and multidrug-resistant bacteria have increased dramatically in recent years and could difficult the treatment. METHODS: The aim of the study was to determine multidrug-resistant bacteria, antibiotic resistance profile, virulence traits, and genetic background of 110 E. coli isolated from community (79 isolates) and hospital-acquired (31 isolates) urinary tract infections. The plasmid-mediated quinolone resistance genes presence was also investigated. A subset of 18 isolates with a quinolone-resistance phenotype was examined for common virulence genes encoded in diarrheagenic and extra-intestinal pathogenic E. coli by a specific E. coli microarray. RESULTS: Female children were the group most affected by UTIs, which were mainly community-acquired. Resistance to trimethoprim-sulfamethoxazole, ampicillin, and ampicillin-sulbactam was most prevalent. A frequent occurrence of resistance toward ciprofloxacin (47.3%), levofloxacin (43.6%) and cephalosporins (27.6%) was observed. In addition, 63% of the strains were multidrug-resistant (MDR). Almost all the fluoroquinolone (FQ)-resistant strains showed MDR-phenotype. Isolates from male patients were associated to FQ-resistant and MDR-phenotype. Moreover, hospital-acquired infections were correlated to third generation cephalosporin and nitrofurantoin resistance and the presence of kpsMTII gene. Overall, fimH (71.8%) and fyuA (68.2%), had the highest prevalence as virulence genes among isolates. However, the profile of virulence genes displayed a great diversity, which included the presence of genes related to diarrheagenic E. coli. Out of 110 isolates, 25 isolates (22.7%) were positive to qnrA, 23 (20.9%) to qnrB, 7 (6.4%) to qnrS1, 7 (6.4%) to aac(6')lb-cr, 5 (4.5%) to qnrD, and 1 (0.9%) to qnrC genes. A total of 12.7% of the isolates harbored bla(CTX-M) genes, with bla(CTX-M-15) being the most prevalent. CONCLUSIONS: Urinary tract infection due to E. coli may be difficult to treat empirically due to high resistance to commonly used antibiotics. Continuous surveillance of multidrug resistant organisms and patterns of drug resistance are needed in order to prevent treatment failure and reduce selective pressure. These findings may help choosing more suitable treatments of UTI patients in this region of Mexico. | 2018 | 30041652 |
| 2674 | 18 | 0.9998 | Phylogeny, virulence factors and antimicrobial susceptibility of Escherichia coli isolated in clinical bovine mastitis. The aim of this study was to identify specific phylogeny groups, virulence genes or antimicrobial resistance traits of Escherichia coli isolated in bovine mastitis associated to clinical signs, persistence of intramammary infection in the quarter and recovery from mastitis. A total of 154 E. coli isolates from bovine clinical mastitis, 144 from the acute stage and 10 from follow-up samples 3 weeks later, originating from 144 cows in 65 dairy herds in Southern Finland were investigated. Phylogeny groups and virulence genes of the isolates were determined using polymerase chain reaction, and antimicrobial susceptibility using the VetMIC™ microdilution method. In ten cows (11.8%), infection persisted, confirmed by re-isolation of the same pulsed-field gel electrophoresis type from the affected quarter at 3 weeks post-treatment. The majority of isolates, 119 (82.6%), belonged to phylogeny group A, which mainly consisted of commensal strains. Altogether 56 isolates (38.9%) had at least one virulence gene detected. Most common virulence genes detected were irp2, iucD, papC iss; genes svg, stx1, stx2, cnf1 and hlyA were not found. Combinations of virulence genes varied greatly. Forty (27.8%) of the 144 E. coli isolates showed resistance to at least one antimicrobial tested. None of the studied phylogeny groups, virulence factors or antimicrobial resistance traits was associated with clinical signs, persistence of intramammary infection or clinical recovery from mastitis. The results support the conclusion that mastitis-causing E. coli bacteria are typical commensals. | 2011 | 20729012 |
| 2146 | 19 | 0.9998 | Study of aminoglycoside resistance genes in enterococcus and salmonella strains isolated from ilam and milad hospitals, iran. BACKGROUND: Aminoglycosides are a group of antibiotics that have been widely used in the treatment of life-threatening infections of Gram-negative bacteria. OBJECTIVES: This study aimed to evaluate the frequency of aminoglycoside resistance genes in Enterococcus and Salmonella strains isolated from clinical samples by PCR. MATERIALS AND METHODS: In this study, 140 and 79 isolates of Enterococcus and Salmonella were collected, respectively. After phenotypic biochemical confirmation, 117 and 77 isolates were identified as Enterococcus and Salmonella, respectively. After the biochemical identification of the isolates, antibiotic susceptibility for screening of resistance was done using the Kirby-Bauer method for gentamicin, amikacin, kanamycin, tobramycin and netilmycin. DNA was extracted from resistant strains and the presence of acc (3)-Ia, aac (3')-Ib, acc (6)-IIa ,16SrRNA methylase genes (armA and rat) was detected by PCR amplification using special primers and positive controls. RESULTS: Enterococcus isolates have the highest prevalence of resistance to both kanamycin and amikacin (68.4%), and Salmonella isolates have the highest prevalence of resistance against kanamycin (6.9%). Ninety-three and 26 isolates of Enterococcus and Salmonella at least were resistant against one of the aminoglycosides, respectively. Moreover, 72.04%, 66.7%, and 36.6% of the resistant strains of Enterococcus had the aac (3')-Ia, aac (3')-IIa, and acc (6')-Ib genes, respectively. None of the Salmonella isolates have the studied aminoglycoside genes. CONCLUSIONS: Our results indicate that acetylation genes have an important role in aminoglycoside resistance of the Enterococcus isolates from clinical samples. Moreover, Salmonella strains indicate very low level of aminoglycoside resistance, and aminoglycoside resistance genes were not found in Salmonella isolates. These results indicate that other resistance mechanisms, including efflux pumps have an important role in aminoglycoside resistance of Salmonella. | 2015 | 26034551 |