ESBL-producing Strains Research Articles

Highly resistant Salmonella Heidelberg circulating in broiler farms in southern Brazil.

Salmonella Heidelberg, a serotype commonly found in Southern Brazil, is characterized by its high resistance and persistence in the poultry production. This study aimed to characterize the antimicrobial resistance of S. Heidelberg strains. In total, 100 strains isolated from poultry between 2020 and 2022 were evaluated. Phenotypic analyses were performed to determine the susceptibility of 16 antimicrobial agents and detect extended-spectrum beta-lactamase (ESBL)-producing strains. Molecular analyses were performed to detect 11 antimicrobial resistance genes (using polymerase chain reaction [PCR]) and integron class 1 genes (using real-time PCR). A total of 98% of isolates was classified as multidrug-resistant. All isolates were resistant to penicillin and lincomycin. High resistance rates (> 85%) were observed for tetracycline, doxycycline, cephalexin, amoxicillin, and ceftiofur. A significant increase (p < 0.05) in antimicrobial resistance is observed for amoxicillin, cephalexin, and ceftiofur between 2020 and 2022. No significant differences (p > 0.05) were observed in antimicrobial resistance with respect to the region of isolation, season, or company. In total, 25% of isolates were ESBL producers. Integron class 1 gene was detected in only one strain, whereas sul2 was detected in 99%, tet(A) in 66%, blaTEM in 37%, strB in 17%, cmlA in 15%, and tet(B) in 11% of the strains. Other genes were not detected or were detected in < 2% of the strains. The results showed a high overall resistance, which increased over the evaluated period. The high proportions of ESBL-producing and antimicrobial resistant strains represent a risk for highly-resistant S. Heidelberg dissemination across broiler flocks.

Risk factors for Beta-lactam and carbapenem-resistant bacteria causing post-burn infections

Background: Burn patients are predisposed to infection because of the loss of skin barrier protection and low immunity. This study aims to evaluate the risk factors of post-burn infections due to beta-lactam and carbapenem-resistant bacteria (CR) isolated from a major burn unit.Methods: The descriptive study was conducted at Jinnah Hospital Lahore’s Burn and Reconstructive Surgery Centre (JB &amp; RSC) and the Institute of Microbiology and Molecular Genetics (MMG), University of the Punjab, Lahore. The clinical specimens of wound swabs, including the age, gender, socio-economic status, residence, occupation, hospital stay, wards, burn degree, total burnt surface area (TBSA%), etiology of burn, and other factors were recorded. Antimicrobial susceptibility testing (AST), ESBL and CR screening (Beta- lactam and carbapenem resistant bacteria) were performed using CLSI guidelines 2017.Results: The most dominant strain was Pseudomonas spp. 26.5% (n=106), followed by 15% (n=60) Klebsiella spp., and 7.5% (n=30) Acinetobacter spp. with ESBL-producing strains. Compared to nosocomial infections, community-acquired infections were observed in 314 (78.5%) patients with more ESBL production. There was a significant relation between burnt people having an age of ≤ 29 years with ESBL (p=0.985) and carbapenemases (p=0.694) infections. None of the other factors, like low socioeconomic status and more hospital stays had a significant correlation (p &gt; 0.05).Concluded: It has been concluded that MDR gram-negative strains play a serious role in burn infections and demand suitable methods to decrease their number. Pseudomonas spp. was the most common post-burn infection causing bacteria. Unfortunately, a high frequency of burn infections was observed in the patients at a young age.Keywords: Post burn infections; Gram negative; MDR; Beta- lactam; Carbapenem resistant

Diversity, functional classification and genotyping of SHV β-lactamases in Klebsiella pneumoniae.

Interpreting the phenotypes of bla SHV alleles in Klebsiella pneumoniae genomes is complex. Whilst all strains are expected to carry a chromosomal copy conferring resistance to ampicillin, they may also carry mutations in chromosomal bla SHV alleles or additional plasmid-borne bla SHV alleles that have extended-spectrum β-lactamase (ESBL) activity and/or β-lactamase inhibitor (BLI) resistance activity. In addition, the role of individual mutations/a changes is not completely documented or understood. This has led to confusion in the literature and in antimicrobial resistance (AMR) gene databases [e.g. the National Center for Biotechnology Information (NCBI) Reference Gene Catalog and the β-lactamase database (BLDB)] over the specific functionality of individual sulfhydryl variable (SHV) protein variants. Therefore, the identification of ESBL-producing strains from K. pneumoniae genome data is complicated. Here, we reviewed the experimental evidence for the expansion of SHV enzyme function associated with specific aa substitutions. We then systematically assigned SHV alleles to functional classes (WT, ESBL and BLI resistant) based on the presence of these mutations. This resulted in the re-classification of 37 SHV alleles compared with the current assignments in the NCBI's Reference Gene Catalog and/or BLDB (21 to WT, 12 to ESBL and 4 to BLI resistant). Phylogenetic and comparative genomic analyses support that (i) SHV-1 (encoded by bla SHV-1) is the ancestral chromosomal variant, (ii) ESBL- and BLI-resistant variants have evolved multiple times through parallel substitution mutations, (iii) ESBL variants are mostly mobilized to plasmids and (iv) BLI-resistant variants mostly result from mutations in chromosomal bla SHV. We used matched genome-phenotype data from the KlebNET-GSP AMR Genotype-Phenotype Group to identify 3999 K. pneumoniae isolates carrying one or more bla SHV alleles but no other acquired β-lactamases to assess genotype-phenotype relationships for bla SHV. This collection includes human, animal and environmental isolates collected between 2001 and 2021 from 24 countries. Our analysis supports that mutations at Ambler sites 238 and 179 confer ESBL activity, whilst most omega-loop substitutions do not. Our data also provide support for the WT assignment of 67 protein variants, including 8 that were noted in public databases as ESBL. These eight variants were reclassified as WT because they lack ESBL-associated mutations, and our phenotype data support susceptibility to third-generation cephalosporins (SHV-27, SHV-38, SHV-40, SHV-41, SHV-42, SHV-65, SHV-164 and SHV-187). The approach and results outlined here have been implemented in Kleborate v2.4.1 (a software tool for genotyping K. pneumoniae), whereby known and novel bla SHV alleles are classified based on causative mutations. Kleborate v2.4.1 was updated to include ten novel protein variants from the KlebNET-GSP dataset and all alleles in public databases as of November 2023. This study demonstrates the power of sharing AMR phenotypes alongside genome data to improve the understanding of resistance mechanisms.

Escherichia coli, an important Uropathogen: Characteristics and antimicrobial susceptibility pattern at Prof. Dr. I.G.N.G. Ngoerah General Hospital, period January 2020 – December, 2021

Background: Urinary tract infections (UTIs) are among the most common infections globally, often treated empirically with broad-spectrum antibiotics without prior culture and sensitivity testing. This practice has contributed to the rise in antibiotic resistance. Escherichia coli (E. coli) is the primary pathogen in uncomplicated UTIs, accounting for 70–90% of cases. However, other bacteria such as Klebsiella pneumoniae, Proteus mirabilis, and Enterococcus faecalis are also significant, especially in complicated or healthcare-associated UTIs. This study examines the resistance patterns of E. coli in UTI cases. Method: A descriptive cross-sectional study was conducted using secondary data from medical records of UTI patients treated at Prof. Dr. I.G.N.G. Ngoerah General Hospital from January 2020 to December 2021. E. coli isolates were identified, and antibiotic sensitivity tests were performed using the VITEK® 2 compact automatic system, with antimicrobial sensitivity and resistance determined according to Clinical and Laboratory Standards Institute (CLSI) guidelines. Result: Analysis of 639 UTI patients revealed that E. coli exhibited high resistance to cefixime (13.3%), ciprofloxacin (23.8%), and trimethoprim-sulfamethoxazole (35.2%). The highest levels of susceptibility were observed with Tigecycline, Meropenem, and Ertapenem, with rates ranging from 99.2% to 99.8%. The demographic data showed a higher incidence of UTIs in female patients (70.9%) compared to males (29.1%), with the majority of cases occurring in adults (94.52%). Additionally, 52.26% of the E. coli isolates were ESBL-producing strains, complicating treatment options. Conclusion: The study underscores the urgent need for judicious antibiotic use, guided by culture and sensitivity testing, to combat the rising threat of antibiotic-resistant UTIs. Tigecycline, Meropenem, and Ertapenem should be prioritized in treatment protocols for multidrug-resistant cases. Continuous surveillance and the development of new antimicrobial agents are essential to address this escalating public health challenge

Phenotypic and Genotypic Profiles of Extended-Spectrum Beta-Lactamase-Producing Multidrug-Resistant Klebsiella pneumoniae in Northeastern Thailand.

The global emergence of extended-spectrum beta-lactamase (ESBL)-producing Klebsiella pneumoniae presents a significant public health threat and complicates antibiotic treatment for infections. This study aimed to determine the prevalence of ESBL-producing K. pneumoniae in a clinical setting, analyze their antimicrobial susceptibility profiles, and characterize both phenotypic and genetic determinants. A total of 507 non-duplicate clinical isolates of Enterobacterales were collected between 2019 and 2020, and third-generation cephalosporin resistance was screened by disk diffusion. Identification of K. pneumoniae was confirmed using biochemical tests and PCR with species-specific primers. Antimicrobial susceptibility testing was conducted using disk diffusion, and phenotypic ESBL production was confirmed using the combined disk method. Multiplex PCR detected ESBL genes (blaTEM, blaSHV, and blaCTX-M) and identified blaCTX-M groups. The genetic relatedness of ESBL-producing strains was assessed using the ERIC-PCR approach. Fitty-four isolates were confirmed as ESBL producers, all classified as multidrug-resistant (MDR). All ESBL-producing K. pneumoniae isolates exhibited resistance to ampicillin and cefotaxime, with high resistance rates for ciprofloxacin (98.2%), azithromycin (94.4%), piperacillin-tazobactam (88.9%), and trimethoprim (83.3%). Genotypic analysis revealed blaCTX-M was present in 94.4% of isolates, blaSHV in 87%, and blaTEM in 55.5%. The blaCTX-M-1 group was the most prevalent, accounting for 96.1% of isolates. Co-harboring of blaCTX-M, blaSHV, and blaTEM occurred in 42.6% of isolates, with co-carrying of blaCTX-M, and blaSHV was observed in 23/54 isolates. The ERIC-PCR analysis revealed 15 distinct types, indicating high genetic diversity. These findings highlight the urgent need for ongoing monitoring to control the spread of ESBL among K. pneumoniae and emphasize the importance of early detection and appropriate antibiotic selection for effectively treating infection caused by these pathogens.

Phenotypic bacterial epidemiology and antimicrobial resistance profiles in neonatal sepsis at Jimma medical center, Ethiopia: Insights from prospective study.

Epidemiological profiles and the rundown crisis of antimicrobial resistance from bacterial isolates in neonatal sepsis compel regular surveillance to enhance data-driven decision-making. Accordingly, this study aimed to assess the phenotypic epidemiology and antimicrobial resistance profiles of bacteria isolated from clinically suspected neonatal sepsis in Ethiopia. A total of 342 neonates suspected of clinical sepsis were randomly included in a prospective observational study conducted at the neonatal intensive care unit (NICU) of Jimma medical center (JMC) from May 2022 to July 2023. Blood samples were collected from each neonate and subjected to a culture test for identification of bacterial isolates and their antibiotic resistance profiles following the standardized guidelines. The laboratory results, along with relevant clinical data, were recorded using WHONET and analyzed using STATA software. Out of the 342 blood samples that were analyzed, 138 samples (40.4%, 95% CI: 35.1-45.6, P<0.01) exhibited proven bacterial infection. The infection rates were notably higher in males with 85/138 (61.6%, 95% CI: 53.4-69.8, P<0.01) and neonates aged 0-3 days with 81/138 (58.7%, 95% CI: 50.5-66.9, P<0.01). The majority of the infections were attributed to Gram-negative bacteria, accounting for 101/138(73.2%, 95% CI: 65.6-80.7) cases, with 69/101(68.3%, 95% CI: 63.8-72.8) cases involving ESBL-producing strains, while Gram-positive bacteria were responsible for 26.8% (95% CI: 19.3-34.4) of the infections. The predominant isolates included Klebsiella pneumoniae (37.7%, 95% CI: 29.6-45.8), Coagulase-negative Staphylococci (CoNs) (20.3%, 95% CI: 13.6-27.0), and Acinetobacter species (11.6%, 95% CI: 6.0-17.1). Of the total cases, 43/72 (59.7%, 95% CI: 48.4-71.1, P<0.01) resulted in mortality, with 28/72 (38.9%, 95% CI: 27.70-50.1, P<0.03) deaths linked to Extended-Spectrum Beta-Lactamase (ESBL)-producing strains. Klebsiella pneumoniae displayed high resistance rates to trimethoprim-sulfamethoxazole (100%), ceftriaxone (100%), cefotaxime (98.1%), ceftazidime (90.4%), and gentamicin (84.6%). Acinetobacter species showed resistance to ampicillin (100%), cefotaxime (100%), trimethoprim-sulfamethoxazole (75%), ceftazidime (68.8%), chloramphenicol (68.8%), and ceftriaxone (68.8%). Likewise, CoNs displayed resistance to ampicillin (100%), penicillin (100%), cefotaxime (86.0%), gentamicin (57.2%), and oxacillin (32.2%). Multidrug resistance was observed in 88.4% (95% CI: 81.8-93.0) of isolates, with ESBL-producers significantly contributing (49.3%, 95% CI: 45.1-53.5). Furthermore, 23.0% (95% CI: 15.8-31.6) exhibited a prevalent resistance pattern to seven distinct antibiotic classes. The prevalence and mortality rates of neonatal sepsis were significantly high at JMC, with a notable surge in antibiotic and multidrug resistance among bacterial strains isolated from infected neonates, specifically ESBL-producers. These resistant strains have a significant impact on infection rates and resistance profiles, highlighting the requisite for enhanced diagnostic and antimicrobial stewardship, stringent infection control, and further molecular characterization of isolates to enhance neonatal survival.

Easy analysis of bacterial whole-genome sequencing data for clinical microbiologists using open-source Galaxy platform: Characterization of ESBL-producing Enterobacterales from bloodstream infections

ObjectivesClinical microbiologists require easy-to-use open access tools with graphical interfaces to perform bacterial whole-genome sequencing (WGS) in routine practice. This study aimed to build a bioinformatics pipeline on the open-source Galaxy platform, facilitating comprehensive and reproducible analysis of bacterial WGS data in a few steps. We then used it to characterize our local epidemiology of ESBL-producing Enterobacterales isolated from patients with bacteremia. MethodsWe built a bioinformatics pipeline consisting of the following sequential tools: Fastp (input data trimming); FastQC (read quality control); SPAdes (genome assembly); Quast (quality control of genome assembly); Prokka (gene annotation); Staramr (ResFinder database) and ABRicate (CARD database) for antimicrobial resistance (AMR) gene screening and molecular strain typing. Paired-end short read WGS data from all ESBL-producing Enterobacterales strains isolated from patients with bacteremia over one year were analysed. ResultsThe Galaxy platform does not require command line tools. The bioinformatics pipeline was constructed within one hour. It only required uploading fastq files and facilitated systematization of de novo assembly of genomes, MLST typing, and AMR gene screening in one step. Among the 66 ESBL-producing strains analysed, the two most frequent ESBL genes were blaCTX−M-15 (62.1%) and blaCTX−M-27 (13.6%). ConclusionsThe open-access Galaxy platform provides a graphical interface and easy-to-use tools suitable for routine use in clinical microbiology laboratories without bioinformatics specialists. We believe that this platform will facilitate fast and low-cost analysis of bacterial WGS data, especially in resource-limited settings.

Year-round monitoring of antibiotic-resistant bacteria in pristine uppermost stream and estimation of pollution sources

Studies on the conditions and pollution routes of antibiotic-resistant bacteria (ARB) in rivers can help provide countermeasures against the spread of ARB. This study focused on the pristine uppermost stream of a river, where Escherichia coli (E. coli) and enterococci were detected, although the stream flows through a pristine forest catchment. Antibiotic resistance of E. coli and enterococci isolated from the river water, riverbed sediment, and feces of waterside animals, such as birds and Mustelidae, were investigated throughout the year in the pristine uppermost sites. Antibiotic resistance was present in 1.4% (7/494) of the E. coli strains and 3.0% (24/812) of the enterococcal strains, and was low throughout the year. Although antibiotic resistance of bacteria isolated from feces was not detected in this watershed, the prevalence of multidrug-resistant E. coli was 0.4% (1/246) and 0.6% (1/172) in river water and riverbed sediment samples, respectively were observed. The presence of extended-spectrum β-lactamase (ESBL)-producing E. coli was confirmed in river water samples, and genomic analysis revealed that the samples possessed the CTX-M-15 group. Multidrug-resistant strains and ESBL-producing strains were classified as phylogroups B1 and A, respectively, which are E. coli phenotypes isolated from wild animals. Pulsed-field gel electrophoresis revealed analysis targeting enterococci that strains isolated from river water and bird feces were in the same cluster with 100% similarity. Therefore, bird feces are a source of enterococci in the uppermost stream of the river. Because multidrug-resistant bacteria and ESBL-producing bacteria were present in the pristine uppermost stream of the pristine river, urgent elucidation of the spreading routes of ARB is important.

Characteristics of the Klebsiella Pneumoniae Strain Isolated from a Positive Blood Culture of a Premature Newborn Baby According to the Results of Whole Genome Sequencing

Relevance. K. pneumoniae is a common nosocomial pathogen in pediatric hospitals, often characterized by the presence of a wide range of virulence factors and genetic determinants of antibiotic resistance. Аim. To analyze the results obtained during wholegenome sequencing of a Klebsiella pneumoniae strain isolated from a positive blood culture of a premature newborn. Materials and methods. An ESBL-producing strain of K. pneumoniae isolated from a positive blood culture of a newborn premature infant. Sequencing was performed on the MiSeq platform (Illumina). Analysis of DNA nucleotide sequences of the complete genome of K. pneumoniae was carried out using the website of the Center for Genomic Epidemiology. The search for genetic determinants of antibiotic resistance and virulence was carried out using online services. Results and its discussion. The resulting nucleotide sequence was 5,414,099 bp in length, and the proportion of GC nitrogenous bases was 57.3%. The isolated strain belonged to the sequence type ST3559, had 4 genes encoding the synthesis of enzymes that hydrolyze antibacterial drugs from the beta-lactam group, 2 genes providing resistance to quinolones/fluoroquinolones, 1 resistance gene each to trimethoprim, chloramphenicol, fosfomycin and aminoglycoside antibiotics. Most of the virulence factor genes identified in the studied strain ensure the recognition and absorption of iron ions necessary for the competitive functioning of the bacterial cell. K. pneumoniae possesses the acrA efflux pump gene and its regulators, as well as 4 prophage particles and 1 CRISPCas IE system. Conclusions. Whole-genome sequencing of the K. pneumoniae strain isolated from a positive blood culture of a premature newborn allows us to characterize in detail the causative agent of a generalized infection and detect a wide range of genetic determinants of virulence factors and antibiotic resistance. The ESBL-producing strain of K. pneumoniae, as the etiological agent of neonatal sepsis, was characterized by the presence of virulence genes, multidrug resistance, both due to genes encoding enzymes that hydrolyze antibiotics, and due to the presence of efflux pumps and their regulators. The use of the results of traditional cultural research methods together with high-throughput sequencing data is a promising area of scientific research and has a reserve of practical application in the field of clinical medicine, genetics of microorganisms, molecular epidemiology at the local and global levels

Prevalence of plasmid-mediated quinolone resistance genes in extended-spectrum beta-lactamase producing Klebsiella pneumoniae isolates in northern Iran

Plasmid-mediated quinolone resistance (PMQR) in extended-spectrum β-lactamase (ESBL)-producing Klebsiella pneumoniae (K. pneumoniae) contributes to treatment failures, extended hospital stays, and increased mortality percentages. We aimed to determine the prevalence of PMQR genes in ESBL-producing K. pneumoniae isolates from clinical samples in Babol, North of Iran region. This is the first study in this region to investigate this specific association. A total of 95 K. pneumoniae isolates were obtained from hospitalized patients with various clinical infections during March 2022 to February 2023. Disk diffusion and Combination disk method were performed to identification of antimicrobial resistance profiles and ESBL-producing strains. The presence of ESBL and PMQR genes among K. pneumoniae isolates was assessed using polymerase chain reaction (PCR) method. Of the isolates, 68 (71.57 %) were considered as ESBL-producers. The blaTEM, blaSHV and blaCTX-M genes were detected in 74.73 %, 57.89 %, and 41.05 % of K. pneumoniae isolates, respectively. Among the PMQR encoding genes, the highest and lowest frequency was associated to qepA (67.3 %) and qnrA (4.2 %), respectively. The frequency of qnrA, qnrB, qnrS, acc (6′)-Ib-cr, qepA, oqxA, and oqxB genes in 26 MDR-Kp isolates was 11.53 % (n; 3), 69.23 % (n; 18), 65.38 % (n; 17), 73.07 % (n; 19), 80.76 % (n; 21), 84.61 % (n; 22), and 76.92 % (n; 20), respectively. Our result revealed of the 68 ESBL gene-positive isolates, 60 (88.23 %) were positive for the PMQR gene. The co-occurrence of these genes within resistant isolates suggests potential linkage on mobile genetic elements such as plasmids. These findings highlight the significant burden of PMQR determinants in ESBL-producing K. pneumoniae and underscore the urgent need for effective control measures. Implementing robust antimicrobial stewardship programs and strengthening drug-resistance surveillance and control protocols are crucial to prevent the spread of resistant isolates.

Phytochemical Composition, In Silico Molecular Docking Analysis and Antibacterial Activity of Lawsonia inermis Linn Leaves Extracts against Extended Spectrum Beta-Lactamases-Producing Strains of Klebsiella pneumoniae

Klebsiella pneumoniae is an opportunistic Gram-negative bacterium in the Enterobacteriaceae family associated with a wide range of diseases, such as pneumonia, bloodstream infections, meningitis and urinary tract infections. Infections caused by drug-resistant strains of Klebsiella pneumoniae pose a significant threat to the effectiveness of conventional antibiotics. Hence, this has led to the need to explore alternative antimicrobial therapies, especially natural products derived from plant sources. This study assessed the phytochemical composition and antibacterial properties and performed a molecular docking analysis of Henna leaves (Lawsonia inermis L.) extracts on strains of Klebsiella pneumoniae. Crude ethanol and methanol extracts of L. inermis L. were prepared at different concentrations (25, 50, 75 and 100 mg/mL) and tested on extended spectrum beta-lactamases (ESBLs)-producing strains of Klebsiella pneumoniae. Phytocompounds were identified using gas chromatography–mass spectrometry (GC-MS) and further subjected to virtual ligands screening with DataWarrior (v05.02.01) and a molecular docking analysis using AutoDock4.2 (v4.2.6). The active compounds of L. inermis L. were determined by the docking analysis, including phytochemical, physicochemical, pharmacokinetics and docking score. The GC-MS analysis identified 27 phytoconstituents, including ethyl acetate, sclareol, 2-[1,2-dihydroxyethyl]-9-[β-d-ribofuranosyl] hypoxanthine, α-bisabolol and 2-Isopropyl-5-methylcyclohexyl 3-(1-(4-chlorophenyl)-3-oxobutyl)-coumarin-4-yl carbonate. The 27 compounds were then screened for their physicochemical and pharmacokinetic properties. The results revealed that the methanol extracts at 100 mg/mL showed significantly higher (p &lt; 0.05) zones of inhibition (13.7 ± 1.2 mm), while the ethanol extracts at 50 mg/mL were significantly lower (6.3 ± 0.6 mm) compared to all the other treatments. The docking analysis revealed that out of the 27 compounds identified, only twelve (12) compounds have a drug-likeness activity. The 12 compounds were further subjected to docking analysis to determine the binding energies with the CTX-M protein of Klebsiella pneumoniae. Only one compound [CID_440869; (2-[1,2-dihydroxyethyl]-9-[β-d-ribofuranosyl] hypoxanthine)] had the best binding energy of −9.76 kcal/mol; hence, it can be considered a potentially suitable treatment for infections caused by ESBLs-producing strains of Klebsiella pneumoniae. This study has demonstrated that L. inermis L. extracts have antibacterial effects. Further research could explore the potential antimicrobial applications of L. inermis L. extracts to many bacterial strains.

Phenotypic and molecular characterization of multidrug-resistant Enterobacterales isolated from clinical samples in Palestine: a focus on extended-spectrum β-lactamase- and carbapenemase-producing isolates

BackgroundInfections resulting from multidrug-resistant Enterobacterales (MDR-E) pose a growing global threat, presenting challenges in treatment and contributing significantly to morbidity and mortality rates. The main objective of this study was to characterize phenotypically and genetically extended-spectrum β-lactamase- and carbapenemase- producing Enterobacterales (ESBLE and CPE respectively) isolated from clinical samples in the West Bank, Palestine.MethodsA cross sectional study was conducted in October 2023 on clinical bacterial isolates collected from five governmental hospitals in the West Bank, Palestine. The isolates obtained from the microbiology laboratories of the participating hospitals, underwent identification and antibiotic susceptibility testing (AST) using the VITEK® 2 Compact system. ESBL production was determined by the Vitek2 Compact system. A modified carbapenem inactivation method (mCIM) was employed to identify carbapenemase-producing Enterobacterales (CPE). Resistance genes were detected by real-time PCR.ResultsOut of the total 1380 collected isolates, we randomly selected 600 isolates for analysis. Our analysis indicated that 287 (47.83%) were extended-spectrum beta-lactamase producers (ESBLE), and 102 (17%) as carbapenem-resistant Enterobacterales (CRE) isolates. A total of 424 isolates (70.67%) were identified as multidrug-resistant Enterobacterales (MDRE). The most prevalent ESBL species were K. pneumoniae (n = 124; 43.2%), E. coli (n = 119; 41.5%) and E. cloacae (n = 31; 10.8%). Among the CRE isolates, 85 (83.33%) were carbapenemase-producing Enterobacterales (CPE). The most frequent CRE species were K. pneumoniae (n = 63; 61.7%), E. coli (n = 25; 24.5%) and E. cloacae (n = 13; 12.8%). Additionally, 47 (7.83%) isolates exhibited resistance to colistin (CT), with 38 (37.62%) being CT-resistant CRE and 9 (3.14%) being CT-resistant ESBLE while sensitive to carbapenems. We noticed that 11 isolates (6 Klebsiella pneumoniae and 5 Enterobacter cloacae complex) demonstrated sensitivity to carbapenems by phenotype but carried silent CPE genes (1 blaOXA48, and 6 blaNDM, 4 blaOXA48, blaNDM). ESBL-producing Enterobacterales strains exhibited varied resistance patterns across different antibiotic classes. E. coli isolates showed notable 48% resistance to trimethoprim/sulfamethoxazole. K. pneumoniae isolates displayed a significant resistance to trimethoprim/sulfamethoxazole, nitrofurantoin, and fosfomycin (54%, 90%, and 70% respectively). E. cloacae isolates showed complete resistance to nitrofurantoin and fosfomycin. P. mirabilis isolates exhibited high resistance against fluoroquinolones (83%), and complete resistance to trimethoprim/sulfamethoxazole, nitrofurantoin and fosfomycin.ConclusionThis study showed the high burden of the ESBLE and CRE among the samples collected from the participating hospitals. The most common species were K. pneumoniae and E. coli. There was a high prevalence of blaCTXm. Adopting both conventional and molecular techniques is essential for better surveillance of the emergence and spread of antimicrobial-resistant Enterobacterales infections in Palestine.

Diversity and Antibiotic Susceptibility of Extended-Spectrum Beta-Lactamase-Producing Enterobacteriaceae from the Urine of Human Population Using Bacteria-Contaminated Water in Butembo Urban Area (DR Congo, Central Africa)

Aims: This study aims to investigate the extended-spectrum beta-lactamases (ESBLs)-producing Enterobacteriaceae in the human urine samples and to understand the potential influence of the contaminated water the urine donors use. Study Design and Methodology: One hundred urine samples from females and the same number from males were collected from donors of different age groups and analysed. One hundred urine samples from females and the same number from males were collected from donors of different age groups. The enterobacterial isolation was done on CLED agar medium. Their identification was carried out first by the enzymatic technic, then using MALDI–TOF MS method. ESBLs-producing enterobacteria were identified by searching the synergy between Clavulanic acid and 3rd generation Cephalosporins. The antimicrobial susceptibility tests were carried out using the disk diffusion method. Results: In male urine samples, the identified ESBLs-producing strains belong to E. coli, E. agglomerans and K. pneumoniae. They were in 11 samples: 3 from donors aged 20 years or less, 3 also from those aged 21 to 40 years as well as in those aged 41 to 60 years, and 2 in samples from donors aged over than 60 years. In female urine samples, the identified ESBLs-producing strains belong to Escherichia coli, Enterobacter agglomerans, Yersinia frederiksenii, Salmonella typhi and Klebsiella pneumoniae. They were in 27 samples: 3 from donors aged 20 years or less, 9 from those aged 21 to 40 years, 12 from those aged 41 to 60 years, and 3 from donors aged over than 60 years. All the strains were sensitive to Imipenem and resistant to Cefotaxim, Ceftazidin, Amoxicillin+Clavulanic acid and Nitrofurantoin. The Multi-Antibiotic Resistance (MAR) index varied from 0.416 (E. coli strains, youngest male donors) to 0.916 (E. coli strains, old female donors). Most of strains react differently from one antibiotic to another (P&lt;0.05), with the exception of E. coli strains from most samples. Most of the identified ESBLs-producing species have been reported in surface and groundwater the population use. These water resources could play a role in the human urinary tract infections. Conclusion: There is a serious health problem with great MAR indices for all bacterial species identified. Treating water before use could reduce the viability and spreading of ESBLs-producing bacteria and genes into the population.

An engineered prodrug selectively suppresses β-lactam resistant bacteria in a mixed microbial setting.

The rise of β-lactam resistance necessitates new strategies to combat bacterial infections. We purposefully engineered the β-lactam prodrug AcephPT to exploit β-lactamase activity to selectively suppress resistant bacteria producing extended-spectrum-β-lactamases (ESBLs). Selective targeting of resistant bacteria requires avoiding interaction with penicillin-binding proteins, the conventional targets of β-lactam antibiotics, while maintaining recognition by ESBLs to activate AcephPT only in resistant cells. Computational approaches provide a rationale for structural modifications to the prodrug to achieve this biased activity. We show AcephPT selectively suppresses gram-negative ESBL-producing bacteria in clonal populations and in mixed microbial cultures, with effective selectivity for both lab strains and clinical isolates expressing ESBLs. Time-course NMR experiments confirm hydrolytic activation of AcephPT exclusively by ESBL-producing bacteria. In mixed microbial cultures, AcephPT suppresses proliferation of ESBL-producing strains while sustaining growth of β-lactamase-non-producing bacteria, highlighting its potential to combat β-lactam resistance while promoting antimicrobial stewardship.

First report of Shigella sonnei carrying a blaCTX-M-15 sexually transmitted among men who have sex with men.

Epidemiology of shigellosis has drastically changed in recent years due to globalization and sexual risk behaviors. Here, through whole-genome sequencing, we characterized two ESBL-producing Shigella sonnei strains (ShSoBUH1 and ShSoBUH2) carrying a blaCTX-M-15 among men who have sex with men (MSM), who had not recently traveled and presented sexual risk behaviors. Both strains harbored IncB/O/K/Z and IncFII plasmids, which carry aadA1, aadA5, sul1, sul2, dfrA1, dfrA17, mph(A), erm(B), tet(B), qacE and blaCTX-M-15 genes conferring resistance to 2nd and 3rd generation cephalosporins, cotrimoxazole, erythromycin, azithromycin and quinolones. IncFII plasmids containing blaCTX-M-15 from ShSoBUH1 and ShSoBUH2 presented 99,8-99,9% similarity with plasmids from another five CTX-M-15 S. sonnei strains detected in Belgium and Switzerland. A single-nucleotide polymorphism (SNP) analysis determined that the study strains differed by 361 SNPs, belonging to different clusters. To the best of our knowledge, this is the first report describing two extensively drug-resistant (XDR) CTX-M-15 S. sonnei strains in MSM.

Antibiofilm activity of promethazine against ESBL-producing strains of Escherichia coli in urinary catheters

The bacterium Escherichia coli is one of the main causes of urinary tract infections. The formation of bacterial biofilms, especially associated with the use of urinary catheters, contributes to the establishment of recurrent infections and the development of resistance to treatment. Strains of E. coli that produce extended-spectrum beta-lactamases (ESBL) have a greater ability to form biofilms. In addition, there is a lack of drugs available in the market with antibiofilm activity. Promethazine (PMZ) is an antihistamine known to have antimicrobial activity against different pathogens, including in the form of biofilms, but there are still few studies of its activity against ESBL E. coli biofilms. The aim of this study was to evaluate the antimicrobial activity of PMZ against ESBL E. coli biofilms, as well as to assess the application of this drug as a biofilm prevention agent in urinary catheters. To this end, the minimum inhibitory concentration and minimum bactericidal concentration of PMZ in ESBL E. coli strains were determined using the broth microdilution assay and tolerance level measurement. The activity of PMZ against the cell viability of the in vitro biofilm formation of ESBL E. coli was analyzed by the MTT colorimetric assay and its ability to prevent biofilm formation when impregnated in a urinary catheter was investigated by counting colony-forming units (CFU) and confirmed by scanning electron microscopy (SEM). PMZ showed bactericidal activity and significantly reduced (p < 0.05) the viability of the biofilm being formed by ESBL E. coli at concentrations of 256 and 512 μg/ml, as well as preventing the formation of biofilm on urinary catheters at concentrations starting at 512 μg/ml by reducing the number of CFUs, as also observed by SEM. Thus, PMZ is a promising candidate to prevent the formation of ESBL E. coli biofilms on abiotic surfaces.

Association Between Biofilm Formation and Extended-Spectrum Beta-Lactamase Production in Klebsiella pneumoniae Isolated from Fresh Fruits and Vegetables.

The presence of extended-spectrum beta-lactamase (ESBL)-producing Klebsiella pneumoniae in fresh fruits and vegetables is a growing public health concern. The primary objective of this study was to investigate the relationship between biofilm formation and extended-spectrum β-lactamase (ESBL) production in K. pneumoniae strains obtained from fresh fruits and vegetables. Out of 120 samples analysed, 94 samples (78%) were found to be positive for K. pneumoniae. Among the K. pneumoniae strains isolated, 74.5% were from vegetables, whereas the remaining (25.5%) were from fresh fruits. K. pneumoniae isolates were resistant to at least three different classes of antibiotics, with ceftazidime (90%) and cefotaxime (70%) showing the highest resistance rates. While the high occurrence of ESBL-producing and biofilm-forming K. pneumoniae strains were detected in vegetables (73.5% and 73.7%, respectively), considerable amounts of the same were also found in fresh fruits (26.5% and 26.3%, respectively). The results further showed a statistically significant (P < 0.001) association between biofilm formation and ESBL production in K. pneumoniae strains isolated from fresh fruits and vegetables. Furthermore, the majority (81%) of the ESBL-producing strains harbored the blaCTX-M gene, while a smaller proportion of strains carried the blaTEM gene (30%), blaSHV gene (11%) or blaOXA (8%). This study highlights the potential public health threat posed by K. pneumoniae in fresh fruits and vegetables and emphasizes the need for strict surveillance and control measures.

Evaluation of adhesin genes and risk factors associated with urinary tract infections by drug-resistant uropathogenic Escherichia coli in North of Iran.

Uropathogenic Escherichia coli (UPEC) isolates, have a wide variety of virulence factors to promote colonization and survival in the urinary tract. This study aimed to evaluate adhesin genes, biofilm formation ability, antibiotic resistance profiles of UPEC strains, and the related risk factors in patients with UTIs caused by drug-resistant UPEC. A total of 105 UPEC isolates were evaluated for biofilm formation using 96-well microtiter plates, the presence of adhesin genes by PCR assay and the antimicrobial susceptibility pattern using the disk diffusion method. Demographic and clinical characteristics of patients were investigated to identify predisposing factors for drug-resistant isolates. Out of 105 UPEC isolates, 84.8% were positive for biofilm formation. Biofilm-producing isolates exhibited a significantly higher prevalence of fimH, kpsMTII, csgA, afa/draBC, and pap adhesin genes compared to non-biofilm-producing strains (p < 0.05). The results also revealed that 52.4% of the isolates were ESBL-producing, and 84.8% were multidrug-resistant (MDR). Further analysis of antibiotic susceptibility among ESBL-producing strains showed the highest resistance rates to ampicillin, ciprofloxacin, and trimethoprim-sulfamethoxazole. Conversely, the highest susceptibility, in addition to carbapenems, was observed for fosfomycin, amikacin, cefoxitin, and nitrofurantoin. We identified hypertension as a potential risk factor for infection with ESBL-producing UPEC strains. Our results revealed a significant rate of drug resistance among UPEC isolates obtained from UTIs in our region. This underscores the importance of monitoring the empirical use of antibiotics and identifying specific risk factors in our geographical area to guide the selection of appropriate empirical treatment for UTIs.

Prevalence of Antibiotic Resistance and Virulence Genes in Escherichia coli Carried by Migratory Birds on the Inner Mongolia Plateau of Northern China from 2018 to 2023.

(1) Background: Antibiotic resistance in bacteria is an urgent global threat to public health. Migratory birds can acquire antibiotic-resistant and pathogenic bacteria from the environment or through contact with each other and spread them over long distances. The objectives of this study were to explore the relationship between migratory birds and the transmission of drug-resistant pathogenic Escherichia coli. (2) Methods: Faeces and swab samples from migratory birds were collected for isolating E. coli on the Inner Mongolia Plateau of northern China from 2018 to 2023. The resistant phenotypes and spectra of isolates were determined using a BD Phoenix 100 System. Conjugation assays were performed on extended-spectrum β-lactamase (ESBL)-producing strains, and the genomes of multidrug-resistant (MDR) and ESBL-producing isolates were sequenced and analysed. (3) Results: Overall, 179 isolates were antibiotic-resistant, with 49.7% MDR and 14.0% ESBL. Plasmids were successfully transferred from 32% of ESBL-producing strains. Genome sequencing analysis of 91 MDR E. coli strains identified 57 acquired resistance genes of 13 classes, and extraintestinal pathogenic E. coli and avian pathogenic E. coli accounted for 26.4% and 9.9%, respectively. There were 52 serotypes and 54 sequence types (STs), including ST48 (4.4%), ST69 (4.4%), ST131 (2.2%) and ST10 (2.2%). The international high-risk clonal strains ST131 and ST10 primarily carried blaCTX-M-27 and blaTEM-176. (4) Conclusions: There is a high prevalence of multidrug-resistant virulent E. coli in migratory birds on the Inner Mongolian Plateau. This indicates a risk of intercontinental transmission from migratory birds to livestock and humans.

A Concurrent Extended Spectrum Beta-lactamase Production and Multidrug Resistance among Proteus Species isolated from Clinical samples of patients attending selected Hospitals in North Eastern Nigeria.

Proteus species are rod-shaped, Gram-negative bacteria that cause opportunistic infections in the urinary tract and occasionally in the gastrointestinal tract. They are implicated in infections like cystitis and pyelonephritis, particularly in immunocompromised individuals, and are frequently present in cases of asymptomatic bacteriuria. Herein, we aimed to investigate the co-occurrence of extended-spectrum beta-lactamase (ESBL) enzyme production and multidrug resistance (MDR) among Proteus spp. Isolated from patients attending selected hospitals in Northeastern Nigeria. A total of 1,500 clinical samples from consenting patients across six states in the Northeastern region of Nigeria were collected. The samples were cultured on Blood agar, and growth resembling that of Proteus species were again subcultured onto MacConkey agar to obtain discrete colonies, further confirmed using biochemical tests. Antibiotics susceptibility test was carried out for all isolates using the Kirby-Bauer disc diffusion method, coupled with a screening of the production of extended-spectrum beta-lactamase using the Combined Disc Diffusion Method. Of the 1500 samples collected, 144 yielded positive growth for Proteus spp., resulting in a prevalence rate of 9.60%. Among these Proteus isolates, three species were identified, with Proteus mirabilis (90.97%) being the most abundant, followed by Proteus vulgaris (8.33%) and Proteus penneri (0.70%). The Proteus isolates displayed significant resistance to β-lactam antibiotics, with a Mean ± SD of 96.64 ± 22.73. A substantial portion of the Proteus spp. Isolated exhibited multidrug resistance (87.89%), with Proteus mirabilis (82.27%) being the most prevalent MDR species. Moreover, about 71.0% of the Proteus spp were ESBL producers, with Proteus mirabilis (64.54%) being the most predominant. Furthermore, 67.38% of all isolates exhibited MDR and ESBL production, and Proteus mirabilis (62.41%) was the most significant among the three Proteus species. These findings highlight the occurrence of multidrug resistance and ESBL production among Proteus spp. in Northeastern Nigeria, with Proteus mirabilis particularly noteworthy. This information is crucial for guiding clinical decision-making, especially in managing infections caused by multidrug-resistant and ESBL-producing Proteus strains.