blaCTX-M Genes Research Articles

Prevalence and Risk Factors of β-Lactamase Genes of Extended-Spectrum β-Lactamases-Producing Escherichia coli From Dairy Farm Environments of Haryana, India.

Presence of extended-spectrum β-lactamases (ESBL)-producing Enterobacteriaceae in the dairy farm environment and food chain could be a possible interface for the exchange of antimicrobial resistance genes between humans and animals. A total of 600 samples comprised of raw bovine milk, faeces, feed, environmental swabs and water samples from 20 different bovine dairy farms in and around Hisar city, Haryana, India were analysed for presence of ESBL encoding genes. Out of 240 isolates of Escherichia coli obtained, 74 isolates were found to be ESBL producers. Maximum number of ESBL isolates were found from faeces (40.5%) followed by raw milk (37.8%) and environmental swabs (17.5%). Most of the ESBL E. coli isolates were sensitive to chloramphenicol (82.4%) and gentamicin (77.0%) antibiotics. The bla CTX-M gene was found to be most prevalent (52.0%) followed by bla TEM (9.45%) while bla SHV gene alone was not detected in any sample by simplex PCR. However, the co-expression of blaCTX-M + blaTEM (21.6%) and blaCTX-M + blaSHV (4.05%) genes were also observed. The housing system, milking method and the hygienic mangement practices followed at farm level are found to be significant risk factors of ESBL-producing E. coli in dairy farms of Haryana.

PCR detection of spreading TEM and CTX-M gene in Klebsiella pneumoniae isolated from urinary tract infection

Mostly, urine is devoid of bacteria, viruses, and fungi, making it sterile. However, an infection may arise when minuscule organisms, mostly bacteria from the digestive system, attach to the urethral opening and proliferate, leading to infections. This research seeks to identify the B-lactam genes responsible for antibiotic resistance in Klebsiella pneumoniae linked with infections, as well as their resistance to treatments. This inquiry specifically focuses on this aspect. The primary focus of the study was identifying bacterial isolates by established diagnostic methods. The secondary objective was to assess the resistance and sensitivity of antibiotics. Lastly, the study used the Polymerase Chain Reaction (PCR) method to ascertain the presence of the blaCTX-M and blaTEM genes. Within the period from November 2022 to June 2023, a 540 clinical samples were gathered from patients with urinary tract infections at Al-Hakim General Hospital, Al-Sadr City Hospital, Al-Furate Al-Awsat Hospital, and Al-Zahra Maternity and Children in AL-Najaf governorate. A total of 120 samples were found to be tainted with Klebsiella pneumoniae. This study assessed the sensitivity of the test using the disk diffusion method. The findings indicated that Klebsiella pneumoniae exhibited high levels of resistance to a road scope of antibiotics, namely Ampicillin/sulbactam, Ampicillin, and Ticarcillin/Clavulanic acid. Additionally, some isolates showed resistance to Cefotaxime. The experiment yielded diverse outcomes for the quinolone, aminoglycoside, and macrolide groups. Among the 120 samples that were examined, 87 of them showed positive results for K. pneumoniae when the PCR technique was used to detect the presence of the blaCTX-M gene. On the other hand, 36 samples tested positive for K. pneumoniae when the blaTEM gene was used. The specimens were obtained from the urine of individuals diagnosed with urinary tract infections.

Prevalence, molecular characterization, and antimicrobial resistance among Escherichia coli, Salmonella spp., and Staphylococcus aureus strains isolated from Egyptian broiler chicken flocks with omphalitis.

Bacterial Omphalitis has been reported as a significant cause of mortalities in newly hatched broiler chicks. This study aimed to assess the occurrence of omphalitis among broiler chickens in Gharbia governorate in Egypt. In addition, the bacteria associated with the occurrence of omphalitis in broiler chickens were also investigated and characterized. For this purpose, 43 farms in that area were surveyed. The comparative levels of omphalitis caused by Escherichia coli (E. coli), Salmonella spp., and Staphylococcus aureus (S. aureus) were screened in 129 chicks. The drug resistance to eight commonly used antimicrobials in Egyptian poultry farms was screened using the disk diffusion method. The overall incidence rate of omphalitis was 37.21%. In birds with omphalitis, the co-prevalence of S. aureus, Salmonella spp., and E. coli was 87.5%. When compared to healthy flocks, broiler chicks with omphalitis caused by Salmonella spp., E. coli, and S. aureus had a greater mortality rate in the first week of life. However, there were no significant differences in the mortality cases caused by these pathogens. Eighty-seven percent of the cases of omphalitis were linked to E. coli and 75% to Salmonella spp. and S. aureus. From the yolk sac of broiler chicks with omphalitis, E. coli, Salmonella spp., and S. aureus were isolated at rates of 87.5%, 62.5%, and 45.8%, respectively. The isolates of E. coli and Salmonella spp. exhibited great sensitivity to gentamycin and Tetracycline; however, the strongest drug resistance was observed toward cefpodoxime, sulphamethoxazole and trimethoprim, ampicillin, and amoxycillin and clavulanic acid. The recovered isolates of S. aureus showed susceptibility to chloramphenicol (72.37%), oxytetracycline (81.82%), and erythromycin (81.82%). However, every S. aureus isolate that was found resistant to amoxycillin and clavulanic acid, penicillin G and oxacillin. of blaTEM, blaSHV, and blaCTX-M genes has been proposed as the genetic cause of β-lactam antibiotic resistance in Salmonella spp. and E. coli. MecA and blaZ; however, were found in every strain of S. aureus. The frequency of omphalitis and its associated mortalities was comparatively high in Gharbia governorate. More efforts should be made to adopt strict hygienic standards for controlling and preventing such disease and this will consequently lead to minimizing the use of antimicrobials in poultry farms.

Analysis of the presence of the blaCTX-M genes in Escherichia coli isolated from downstream of the Bekasi River

Antimicrobial resistance (AMR) is a global public health threat caused by antibiotic resistance genes (ARGs), such as blaCTX-M. The blaCTX-M is one of the most common ARGs that confers cephalosporin resistance. This study aimed to investigate the concentrations of cefotaxime-resistant Escherichia coli (E. coli) and the presence of the blaCTX-M in E. coli isolated from downstream of the Bekasi River. The results of this study provided some information on AMR in reservoir environmental bacteria. This study used polymerase chain reaction (PCR) to amplify DNA and gel electrophoresis to visualize the target genes. The results are downstream of the Bekasi River had an average concentration of non-selective E. coli (2,3 ± 0,4) × 104 CFU/100mL and the average concentration of cefotaxime-resistant E. coli (2,1 ± 0,6) × 103 CFU/100 mL. The ratio of antibiotic-resistant E. coli to non-selective E. coli was 9.4%. The blaCTX-M genes were detected in 80% of E. coli isolates, with blaCTX-M group 1 genes predominating, which includes the blaCTX-M -1, blaCTX-M-3, and blaCTX-M-15 genes.

Occurrence of extended-spectrum beta-lactamase producing escherichia coli in groundwater

Groundwater is a vital source of clean water globally. The presence of E.coli, specifically ESBL-producing E.coli (ESBL-Ec), in groundwater can pose a significant risk to human health. This study aimed to analyze the concentrations of E.coli and ESBL-Ec in five groundwater samples (A1-A5) near the Cipayung landfill, as well as one groundwater (A6) from a residential area. Morevorer, one septic tank sample located near A6 was also collected (ST). Characterization of the the blaCTX-M gene associated with cefotaxime resistance were conducted. Phenotypic analysis involved the Double Disk Sinergy Test to confirm ESBL enzyme activity against antibiotics, while genotypic analysis utilized the Multiplex PCR to characterize the blaCTX-M gene. Results indicated that the E. coli concentrations in groundwater ranged from (4.0 ± 2.0) × 10-1 CFU/100 mL to (4.0 ± 0.3) × 103 CFU/100 mL. ESBL-Ec was consistently detected at A1, A2, A4, and ST with average concentrations of (6.5 ± 3.0) × 100 CFU/100 mL, (1.3 ± 0.5) × 100 CFU/100 mL, (1.1 ± 0.1) × 101 CFU/100 mL, and (7.2 ± 1.1) × 103 CFU/100 mL, respectively. Multiplex PCR revealed the presence of blaCTX-M group 1 and group 2 genes at samples A1, A2, A4, and ST. This study highlighted the need for preventive measures to minimize ESBL-Ec spread in groundwater.

Identification and characterization of a plasmid co-harboring blaCTX-M-55 and blaTEM-141 in Escherichia albertii from broiler in China1

The inappropriate use of cephalosporins lead to the occurrence and global spread of bacteria resistant to these antimicrobials. In this study, we isolated four Escherichia albertii (E. albertii) strains from broilers in Eastern China. The antimicrobial susceptibility and genomic characterization of these E. albertii isolates were determined. Our results revealed that these four E. albertii isolates exhibited resistance to tetracyclines, chloramphenicol, β-lactams, aminoglycosides, polymyxin B, sulfonamides, quinolones, and other antimicrobials. Among them, EA04 isolate was multidrug resistant and harbored extended-spectrum β-lactamases (ESBL) genes blaCTX-M and blaTEM. Whole genome sequencing and core-genome Multilocus sequence typing (cgMLST) based on all ST4638 E. albertii for EA04 inferred highly probable epidemiological links between selected human isolates. Additionally, the ESBL genes blaTEM-141 and blaCTX-M-55 were coexistent in an approximately 75 kb IncFII plasmid pEA04.2 in EA04. Comparative analysis indicated that genes blaTEM-141 and blaCTX-M-55 were located in IS15-blaCTX-M-55-wbuC-blaTEM-141-IS26 region, which similar structures were identified in various bacteria. Furthermore, the plasmid pEA04.2 could be transferable to Escherichia coli EC600 and lead to the resistance to third-generation cephalosporins. These results suggested that chicken potentially serve as a reservoir for multidrug resistant E. albertii, which increases the risk of horizontal transfer of antimicrobial resistance between humans, animals and environment.

Prevalence and molecular characterization of Multidrug-Resistant ESBL-Producing E. coli in commercial poultry

Background: Rural poultry farmers are gradually changing from the backyard poultry production to intensive production, which made poultry more vulnerable to diseases and lead to indiscriminate use of antimicrobials in poultry production. As per OIE, FAO and WHO, multiple spread antimicrobial resistant pathogenic bacteria are a serious global human and animal health problem. Hence the study has been carried out to know the antimicrobial resistance status of poultry in Tirunelveli, Tamil Nadu, India. Methods: The study was aimed to find the occurrence of extended spectrum beta lactamases (ESBLs) producing E. coli from poultry origin. Caecum samples from the broiler (n=180), desi chicken (n=180) and Japanese quail (n=180) were processed for the isolation and phenotypic identification of ESBL E. coli. The isolates were tested for antimicrobial susceptibility test and characterization of ESBL and virulence genes done by PCR. Result: On phenotypic confirmation of ESBL producing E. coli by combined disk diffusion test (CDDT), a total of 9.63% samples were positive for extended spectrum beta lactamase producer (ESBL). Multi drug resistance (MDR) was observed in 38.23% of the broiler isolates, 27.27% and 57.14% in desi chicken and Japanese quail isolates, respectively. All the phenotypically confirmed ESBL producing E. coli isolates (n=52) were positive for uspA gene by PCR confirming the isolates as E. coli. The overall presence of the blaTEM gene was 57.69%, with broiler isolates having the highest prevalence of 67.47%, followed by desi chicken 36.36% and Japanese quail 42.85%. In contrast, the blaSHV gene was found in only 17.64% of the broiler isolates, but none were positive for the blaCTXM and blaOXA-1 gene.

Prevalence of multidrug-resistant and extended-spectrum β-lactamase producing Escherichia coli from local and broiler chickens at Cibinong market, West Java, Indonesia.

Antimicrobial resistance (AMR) is becoming a public health concern. Foodborne pathogens are infectious agents that can be transmitted from animals to humans through food and can become resistant due to misuse and overuse of antibiotics, especially in poultry. This study aimed to detect the prevalence of multidrug-resistant and extended-spectrum β-lactamase (ESBL)-producing Escherichia coli isolated from local and broiler chickens at the Cibinong market, West Java, Indonesia. A total of 60 cloacal swab samples from 30 local and broiler chickens sold at the Cibinong market in West Java were obtained by random sampling. From these samples, 39 E. coli isolates were obtained after being cultured on eosin methylene blue agar and molecularly identified using polymerase chain reaction (PCR). Six antibiotic disks were used for the antibiotic sensitivity test against E. coli isolates cultured on Mueller-Hinton agar. PCR was performed to detect ESBL genes (blaTEM, blaSHV, and blaCTX-M). A total of 76.47% (39/51) cloacal swab samples were positive for E. coli. All E. coli isolates were sensitive to imipenem (100%), and 38 isolates were sensitive to cefoxitin (FOX) (97.4%). On average, the isolates were sensitive to amoxicillin-clavulanic acid (AMC) (69.2%) and ceftriaxone (CRO) (89.7%). E. coli isolates were occasionally resistant to enrofloxacin (25.64%), followed by gentamicin (20.51%), CRO (10.25%), AMC (7.69%), and FOX (2.56%). The prevalence of E. coli AMR was 10.25% (4/39). All four multidrug-resistant E. coli isolates (blaTEM and blaCTX-M) were confirmed to have the ESBL gene based on PCR. The prevalence of multidrug-resistant and ESBL-producing E. coli is still found, proving that there is still inappropriate use of antibiotics and a need for strict supervision of their use, especially around Cibinong market, West Java.

Non-replicative phage particles delivering CRISPR-Cas9 to target major blaCTX-M variants.

Cluster regularly interspaced short palindromic repeats and CRISPR associated protein 9 (CRISPR-Cas9) is a promising tool for antimicrobial re-sensitization by inactivating antimicrobial resistance (AMR) genes of bacteria. Here, we programmed CRISPR-Cas9 with common spacers to target predominant blaCTX-M variants in group 1 and group 9 and their promoter in an Escherichia coli model. The CRISPR-Cas9 was delivered by non-replicative phagemid particles from a two-step process, including insertion of spacer in CRISPR and construction of phagemid vector. Spacers targeting blaCTX-M promoters and internal sequences of blaCTX-M group 1 (blaCTX-M-15 and -55) and group 9 (blaCTX-M-14, -27, -65, and -90) were cloned into pCRISPR and phagemid pRC319 for spacer evaluation and phagemid particle production. Re-sensitization and plasmid clearance were mediated by the spacers targeting internal sequences of each group, resulting in 3 log10 to 4 log10 reduction of the ratio of resistant cells, but not by those targeting the promoters. The CRISPR-Cas9 delivered by modified ΦRC319 particles were capable of re-sensitizing E. coli K-12 carrying either blaCTX-M group 1 or group 9 in a dose-dependent manner from 0.1 to 100 multiplicity of infection (MOI). In conclusion, CRISPR-Cas9 system programmed with well-designed spacers targeting multiple variants of AMR gene along with a phage-based delivery system could eliminate the widespread blaCTX-M genes for efficacy restoration of available third-generation cephalosporins by reversal of resistance in bacteria.

Molecular characterization of extended spectrum β-lactamase producing Escherichia coli isolated from bovine mastitic milk in Northern Bangladesh.

Aims: Extended-spectrum beta-lactam (ESBL) antibiotics resistance is one of the top antimicrobial threats globally. Recent evidence suggests the emergence of ESBL-positive Escherichia coli from the animal origin foods. However, information on the animal origin ESBL-positive E. coli is very limited in Bangladesh. The present study investigated the frequency and characteristics of ESBL-positive E. coli in milk samples from cows with mastitis in northern Bangladesh. Methods: The phenotype of ESBL-positive E. coli was determined using ESBL-CHROM agar media and the antibiotic sensitivity was measured by disk diffusion method. PCR was used to detect the E. coli and ESBL-genes of the isolates. Results: This study detected 60 E. coli isolates from 400 milk samples. Among the isolates, ESBL-positive E. coli was detected in 14 (23.33%) isolates according to the results of phenotypic confirmatory methods. Our findings further demonstrated that the most common ESBL gene was blaCTX-M (92.86%), subsequently 71.43% of the isolates had blaTEM. Most of the isolates bearing blaCTX-M gene also harbored with blaTEM gene (78.57%). Interestingly, blaSHV gene was absent in all isolated E. coli strains. Antibiogram revealed 100% of ESBL-positive isolates showed multidrug-resistant (MDR) in nature and exhibited complete resistance to ampicillin. Additionally, 92.86% were resistant to cefuroxime, cefaclor, and cefotaxime, while 85.72% showed resistance to cefpodoxime, amoxicillin-clavulanic acid, and aztreonam. Notably, all isolates were 100% sensitive to carbapenems. Conclusion: This study provides noble evidence on the animal borne ESBL producing E. coli and raises need for vigilant antibiotic stewardship and robust infection control measures.

Multirresistência antimicrobiana e formação de biofilmes em isolados de Salmonella enterica da cadeia produtiva de frangos

ABSTRACT: Poultry and poultry products are considered the predominant sources of Salmonella enterica contamination and are important reservoirs of bacteria with antimicrobial resistance. The objective of this study was to identify Salmonella with multidrug resistance (MDR) phenotype, with the ability to form biofilms and elucidate the presence of genes that encode antimicrobial resistance in isolates from the broiler production chain in the state of Maranhão, Brazil. A total of 121 strains of S. enterica of different serovars were evaluated for antimicrobial susceptibility, and of these, 26 strains were used to detect the ability to form biofilms and identify resistance genes using PCR. Antimicrobial resistance was observed in 95 (78.5%) Salmonella isolates, and 57 (47.1%) showed MDR phenotype. The isolates showed greater resistance to the sulfonamide principles (58.7%), trimethoprim (48.8%), tetracycline (45.4%), nalidixic acid (44.6%), amoxicillin and ampicillin (26.4%), and cefazolin (22.3%). Salmonella Schwarzengrund (n=21/61.7%), Albany (n=15/62.5%), and Enteritidis (n=4/44.5%) showed the highest indices of MDR phenotype. The ability to form biofilms at 37°C was found in 13 of the 26 strains evaluated, which were considered poor producers. The resistance genes blaCTX-M, blaCTX-M2, blaSHV, sul1, sul2, tetA, tetB, tetC, tetE, dfrA12, and dfrA1 were observed in the serovars Schwarzengrund, Albany, Enteritidis, Heidelberg, and Typhimurium. The results showed a high occurrence of S. enterica, with multiple resistance to conventional antimicrobials and the ability to form biofilms in the poultry production chain.

DETERMINING THE OCCURRENCE OF SOME VIRULENCE GENES IN PROTEUS SPECIES ISOLATES

Forty isolates of Gram-negative rod-shaped bacteria termed as Proteus, widely known for their swarming motility and urease activity, which cause complicated urinary tract infections (UTIs), were isolated and identified. Two hundred and ten urine specimens collected from the patients suffering from UTIs, who were hospitalized in Babylon hospitals, were used for the isolation of Proteus species isolates. The morphological features (for cells and colonies), biochemical tests, VITEK 2 compact and polymerase chain reaction (PCR) for Proteus-specific genes were used for the identification of these isolates. The assessment of the antimicrobial profiles that represent the prevalence and the level of pathogenicity of the isolates was also carried out. Furthermore, the whole genomic DNA of the isolates was extracted to determine the sites of blaTEM, blaCTX-M, and blaSHV genes on the genome of the isolates. The results revealed that thirty isolates were P. mirabilis and ten isolates were P. vulgaris. These isolates were given names as PM1 to PM30 for P. mirabilis and PV31 to PV40 for P. vulgaris. The most effective antibiotics against the isolates were erythromycin (97.5%), followed by tobramycin (85%), ampicillin (82.5%), chloramphenicol (60%), piperacillin (55%) and 52.5% for each sulfamethoxazole and azithromycin. The meropenem and imipenem showed less resistance (35%) followed by ciprofloxacin (30%) and gentamicin (15%). The PCR assay exhibited that these isolates carried blaTEM gene at the rate of 38/40 (95%), blaSHV gene at the rate of 33/40 (82.5%) and blaCTX-M gene at the rate of 37/40 (92.5%). Therefore, reducing the frequency and severity of infections, however, more research is needed to understand how the rates of pathogenicity of Proteus species isolates can be controlled.

BlaCTX-M Mediated Extended Spectrum Beta-lactamase Production in Escherichia coli from Urine Samples

Objective: To assess the antimicrobial pattern of Escherichia coli isolates from urine samples, determine the proportion of multidrug resistant (MDR) and extended spectrum beta-lactamase (ESBL) and blaCTX-M gene of E. coli from the urine samples. Methods: A total of 2452 urine samples were collected and processed from April to October 2023 in clinically suspected urinary tract infection (UTI) patients attending B&B Hospital Pvt. Ltd to identify possible bacteria using standard microbiological procedures. E coli isolates were further subjected to antimicrobial susceptibility testing using Kirby Bauer disk diffusion method. Combination disk method was used to identify the ESBL phenotypes. Molecular detection of blaCTX-M gene was performed using conventional polymerase chain reaction. Results: A total of 338 (13.7%) samples showed significant bacterial growth. Maximum bacterial growth was found in outpatients (70.4%) and in patients above 60 years of age. Gram negative bacteria (87.8%) were predominant and E. coli (54.4%) was the most frequent. Nitrofurantoin, Aminoglycosides, Carbapenems and Polymixins were effective antibiotics. Among 184 E. coli isolates, 54 (29%) were MDR, 30 (16.3%) were ESBL producer. blaCTX-M gene was detected in 90% of the phenotypically confirmed ESBL producers. Conclusion: E. coli is the major cause of UTI and blaCTX-M is a prime contributor of ESBL production. High rate of resistance to third-generation Cephalosporins, Flouroquinolones and Cotrimoxazole make these antibiotics unsuitable for the treatment of UTI.

SURVEY ON MULTI-DRUG RESISTANT AND EXTENDED SPECTRUM BETA LACTAMASES PRODUCING BACTERIA ON CONTACT SURFACES AT MURTALA MUHAMMAD SPECIALIST HOSPITAL, MAKKAH EYE CLINIC AND UMC ZHAHIR HOSPITAL, KANO STATE

The contaminated environmental surfaces are not only potential reservoirs for spread of microbial agents inside hospital but also in community. The development and evolution of antimicrobial resistance in pathogen has been reported to be one of the major issues confronting the global health community. Members of family Enterobacteriacae able to produce extended spectrum of beta lactamase which is responsible to hydrolyze the third generation of cephalosporin group antibiotics resulting treatment failure. The use of beta-lactams has increased considerably since its discovery so also resistant genes leading to Extended-Spectrum Beta-Lactamases (ESBL) mediated by the presence of blaCTX-M, blaTEM, and blaSHV genes present in most Gram-negative bacteria. Out of 300 swab samples collected, 218 (72.7%) bacteria were isolated. 158 (72.5%) was gram positive and 60(27.5%) was gram negative. A total of 96(44.0%) isolates were multidrug resistant. Antibiotics susceptibility test was performed by Kirby Bauer technique according to CLSI guidelines. Organisms that tested positive phenotypically for ESBL were subjected to PCR for molecular analysis. ESBL had a percentage rate of 11.3%. The coexistence of bla CTX-M, bla TEM and bla SHV gene was detected

Potential Pathogenicity of Escherichia coli Isolated from the Stools of Healthy Children Suffering from Diarrhea Admitted to Hospitals in Southern Benin

Aims: Infant mortality linked to infectious diseases remains a major public health concern, especially in the context of antibiotic resistance. This work aimed to study the potential pathogenicity of Escherichia coli strains isolated from the stools of children suffering from diarrhea and healthy from 0 to 15 years old admitted to hospitals in southern Benin.
 Methodology: The isolation and characterization of the strains were carried out according to standard microbiology methods. Molecular characterization was carried out by searching for eight virulence factors (Stx1, Stx2, eaeA, bfpB, LT, InVE, IpaH, AggR) and three antibiotic resistance genes (blaTEM, blaSHV, blaCTX -M) by the PCR technique.
 Results: This study shows that 47.06% of the children sampled suffered from diarrhea, against 52.94% who were healthy. A total of 9 species of Enterobacteriaceae were identified in different proportions: Escherichia coli (66.66%), Klebsiella ornithinolytica (13.72%), Klebsiella pneumonia (5.88%), Enterobacter aerogenes (3.92%), Escherichia vulneris (1.96%), Salmonella arizonae (1.96%), Salmonella spp (1.96%), Enterobacter sakazakii (1.96%), Serratia fonticola (1.96%). All E. coli showed total resistance to amoxicillin, ceftazidime, and cefotaxime. In addition, they showed variable resistance to norfloxacin (95.33%), trimethoprim (83.33%), and sulfamethoxazole (95.24%). 70.83% of E. coli strains isolated from apparently healthy children carry resistance genes blaTEM (12.5%), blaSHV (25%), and blaCTX-M (33.33%). While 66.67% of strains of E. coli isolated from children with diarrhea carry resistance genes blaTEM (12.5%), blaSHV (37.5%), and blaCTX-M (16.67%). Only EPEC was isolated and only in diarrheal children, with a frequency of 20.83%.
 Conclusion: The relatively high prevalence of ECD in this study is remarkable, and it highlights the fact that E. coli is an important agent of infectious diarrhea and could be the leading cause of gastroenteritis in Benin.

The secrets of environmental Pseudomonas aeruginosa in slaughterhouses: Antibiogram profile, virulence, and antibiotic resistance genes.

Environmental pollution is a serious problem that can cause sicknesses, fatality, and biological contaminants such as bacteria, which can trigger allergic reactions and infectious illnesses. There is also evidence that environmental pollutants can have an impact on the gut microbiome and contribute to the development of various mental health and metabolic disorders. This study aimed to study the antibiotic resistance and virulence potential of environmental Pseudomonas aeruginosa (P. aeruginosa) isolates in slaughterhouses. A total of 100 samples were collected from different slaughterhouse tools. The samples were identified by cultural and biochemical tests and confirmed by the VITEK 2 system. P. aeruginosa isolates were further confirmed by CHROMagar™ Pseudomonas and genetically by rpsL gene analysis. Molecular screening of virulence genes (fimH, papC, lasB, rhlI, lasI, csgA, toxA, and hly) and antibiotic resistance genes (blaCTX-M, blaAmpC, blaSHV, blaNDM, IMP-1, aac(6')-Ib-, ant(4')IIb, mexY, TEM, tetA, and qnrB) by PCR and testing the antibiotic sensitivity, biofilm formation, and production of pigments, and hemolysin were carried out in all isolated strains. A total of 62 isolates were identified as P. aeruginosa. All P. aeruginosa isolates were multidrug-resistant and most of them have multiple resistant genes. blaCTX-M gene was detected in all strains; 23 (37.1%) strains have the ability for biofilm formation, 33 strains had virulence genes, and 26 isolates from them have more than one virulence genes. There should be probably 60 (96.8%) P. aeruginosa strains that produce pyocyanin pigment. Slaughterhouse tools are sources for multidrug-resistant and virulent pathogenic microorganisms which are a serious health problem. Low-hygienic slaughterhouses could be a reservoir for resistance and virulence genes which could then be transferred to other pathogens.

IS26 drives the dissemination of bla CTX-M genes in an Ecuadorian community.

The horizontal gene transfer events are the major contributors to the current spread of CTX-M-encoding genes, the most common extended-spectrum β-lactamase (ESBL), and many clinically crucial antimicrobial resistance (AMR) genes. This study presents evidence of the critical role of IS26 transposable element for the mobility of bla CTX-M gene among Escherichia coli isolates from children and domestic animals in the community. We suggest that the nucleotide sequences of IS26-bla CTX-M could be used to study bla CTX-M transmission between humans, domestic animals, and the environment, because understanding of the dissemination patterns of AMR genes is critical to implement effective measures to slow down the dissemination of these clinically important genes.

Examining the Frequency of bla CTX-M and bla TEM Genes in Escherichia Coli Isolates with Multiple Drug Resistance Isolated from Patients Hospitalized in Ahvaz University Hospitals

Background and Objectives In the last few decades, Escherichia coli strains producing extended-spectrum beta-lactamases (ESBLs) have increased and are now considered a major problem in hospitalized patients. The aim of this study was to investigate the prevalence of blaCTX-M and blaTEM genes in Escherichia coli with multiple drug resistance. Subjects and Methods This study was conducted from October 2021 to May 2022. The research site included the microbiology laboratories of Golestan, Imam Khomeini, and Shahid Beqai hospitals where isolates suspected of Escherichia coli were isolated from urine culture samples of patients with urinary tract infection. All Escherichia coli samples were identified by conventional biochemical and molecular methods. The antibiotic sensitivity of the isolates was determined by disk diffusion method. Then, in order to finally confirm the presence of blaCTX-M and blaTE genes, PCR method was used. Results Out of the 160 bacterial isolates examined, 138 (86.3%) showed multidrug resistance (MDR). The highest and lowest percentage of resistance was related to Amoxicillin-Clavonic acid (84.1%) and Meropenem (5.8%), respectively. Based on the combined disk method, 96 isolates (69.6%) were positive for Beta-lactamase enzymes (ESBLs). Among the 96 ESBL-positive isolates, 85 (88.5%) and 38 (39.6%) carried blaCTX-M and blaTEM genes, respectively. Conclusion Given the significant prevalence of Escherichia coli strains that are resistant to multiple drugs and carrying ESBLs beta-lactamase genes in hospital, there is a need for effective surveillance measures to prevent the further spread of drug resistance in these isolates.

Role of CTX-M-15 gene in spread of extended-spectrum beta-lactamases among immunocompetent patients in Ghana.

Patients with faecal carriage of extended-spectrum beta-lactamases (ESBL)-producing Enterobacterales serve as reservoirs and sources of dissemination and infection. This report examined immunocompetent patients for faecal carriage of ESBL-producing Enterobacterales in a district care hospital setting in Ghana. Between March 2019 and May 2020, cross-sectional sampling was performed to enrol patients and conduct questionnaire-structured interviews for factors that predispose patients to ESBL faecal carriage. Faecal samples from study patients were quantified for ESBL-producing Enterobacterales. The ESBL genes were characterised by polymerase chain reaction and sequencing. The overall proportion of ESBL faecal carriage was 35.5% (n = 38/107). The blaCTX-M gene, mostly CTX-M-15, was detected in 89.5% (n = 34/38) of the ESBL-producing isolates. The other ESBL types included blaSHV (n = 3) and blaOXA (n = 1). The CTX-M-15-positive isolates, when present in a faecal sample compared to the non-ESBL-CTX-M-15 isolates, constituted the predominant faecal Enterobacterales, with significantly higher colony counts than all other enterobacteria in that sample. In multivariate regression, independent risk factors for faecal carriage of ESBL-producing Enterobacterales were hospitalisation in the past year, infections since admission, use of antibiotics in the past 6 weeks, and admission from another hospital. The study found that CTX-M-15-producing isolates were the predominant faecal Enterobacterales, and that further investigations are needed to determine the reasons behind this dominance. The CTX-M-15-producing isolates dominance in this study shows the misuse and abuse of antibiotics in an African medical facility and indicates the potential role of immunity in controlling ESBL spread, which is to be investigated further.

Isolation and identification of antimicrobial susceptibility, biofilm formation, efflux pump activity, and virulence determinants in multi-drug resistant Pseudomonas aeruginosa isolated from freshwater fishes.

The present study was undertaken to evaluate the prevalence, underlying resistance mechanism, and virulence involved in Pseudomonas aeruginosa (n = 35) isolated from freshwater fishes in Andhra Pradesh, India. Antibiogram studies revealed that 68.5, 62.8, 37.1, 11.4, 8.5, 57.1, 54.2, and 48.5% of isolates had resistance to oxytetracycline, co-trimoxazole, doxycycline, enrofloxacin, ciprofloxacin, cefotaxime, ceftazidime, and ampicillin, respectively. The resistant isolates harboured the tetA (85.7%), tetD (71.4%), tetM (91.4%), sul1 (80%), blaCTX-M (57.1%), blaTEM (42.8%), and blaSHV (48.5%) genes. In total, 50% of the isolates were altered as multi-drug resistant, and the multiple antibiotic resistance index was calculated as 0.4. Furthermore, 37.3, 48.5, and 14.2% of isolates were categorized as strong, moderate, and weak biofilm formers, possessing pslA (91.5%) and pslD (88.6%) biofilm encoding genes. In total, 82.8% of the isolates exhibited efflux pump activity and harboured the mexA (74.2%), mexB (77.1%), and oprM (37.1%) genes. Virulent genes oprL, toxA, exoS, and phzM were detected in 68.5, 68.5, 100, and 17.1% of isolates, respectively. The data suggested that P. aeruginosa harbours multiple resistance mechanisms and virulence factors that may contribute to antibiotic resistance and pathogenicity, and their distribution in fish culture facilities highlights the public health hazards of the food chain.