Beta-lactamase Production Research Articles

Optogenetic patterning generates multi-strain biofilms with spatially distributed antibiotic resistance

Spatial organization of microbes in biofilms enables crucial community function such as division of labor. However, quantitative understanding of such emergent community properties remains limited due to a scarcity of tools for patterning heterogeneous biofilms. Here we develop a synthetic optogenetic toolkit ‘Multipattern Biofilm Lithography’ for rational engineering and orthogonal patterning of multi-strain biofilms, inspired by successive adhesion and phenotypic differentiation in natural biofilms. We apply this toolkit to profile the growth dynamics of heterogeneous biofilm communities, and observe the emergence of spatially modulated commensal relationships due to shared antibiotic protection against the beta-lactam ampicillin. Supported by biophysical modeling, these results yield in-vivo measurements of key parameters, e.g., molecular beta-lactamase production per cell and length scale of antibiotic zone of protection. Our toolbox and associated findings provide quantitative insights into the spatial organization and distributed antibiotic protection within biofilms, with direct implications for future biofilm research and engineering.

Current antibiotic resistance of Enterobacteriaceae isolated at Avicenna military hospital of Marrakesh

Enterobacteriaceae are bacteria found in the digestive system, known for causing infections and displaying antibiotic resistance. The World Health Organization (WHO) identifies strains resistant to third-generation cephalosporins and carbapenems as priority pathogens. This study, conducted at Avicenne Military Hospital of Marrakech, aimed to assess the epidemiological and antibiotic resistance profiles of Enterobacteriaceae over a two-year period (May 2020 - April 2022) to inform updated antibiotic use recommendations. This retrospective study analyzed 1,626 positive bacterial isolates from various hospital departments, including medical, surgical, intensive care, emergency units, and external samples. Of these, 1,163 (71.5%) were Enterobacteriaceae, predominantly Escherichia coli, Klebsiella pneumoniae, and Enterobacter cloacae, primarily isolated from urine, pus, and blood cultures. Antibiotic resistance was assessed, revealing that 614 (52.8%) of Enterobacteriaceae were extended-spectrum beta-lactamase producers (ESBL-E), and 115 (9.9%) were carbapenemase-producing Enterobacteriaceae (CPE). The study’s findings align with existing literature, showing a higher prevalence of Enterobacteriaceae in males and frequent isolation of Escherichia coli. The rise in multidrug-resistant Enterobacteriaceae, particularly ESBL-E and CPE, poses risks such as therapeutic failure, increased morbidity and mortality, and significant economic impacts. To address this, the study emphasizes the importance of early detection, infection control measures, responsible antibiotic prescribing, and collaborative efforts across hospital departments to reduce the spread of resistant strains.

A Descriptive Study on the Phenotypic Variability of Pseudomonas aeruginosa Identified by MALDI-TOF

This descriptive study investigates the phenotypic variability of 50 Pseudomonas aeruginosa colonies isolated from wastewater, identified using MALDI-TOF mass spectrometry. The contamination of wastewater by opportunistic pathogens like P. aeruginosa poses significant public health risks due to their potential to cause severe infections and contribute to the spread of antimicrobial resistance. Pseudomonas aeruginosa is particularly concerning because of its remarkable adaptability, resilience, and intrinsic and acquired antibiotic resistance mechanisms, including the production of beta-lactamases, efflux pumps, and target site mutations. Our study highlights the phenotypic diversity and antibiotic resistance profiles of P. aeruginosa strains isolated from urban and hospital environments. Using MALDI-TOF MS, we rapidly and accurately characterized these strains, providing species-level identification within minutes. This technology surpasses traditional biochemical methods in speed and accuracy, revolutionizing microbial diagnostics by offering a high-throughput, cost-effective, and reliable tool. By analyzing the phenotypic traits and resistance mechanisms of these strains, we aim to provide critical insights into their ecology and inform strategies to mitigate the risks associated with their presence in the environment. The antibiotic resistance profiles revealed varied susceptibility among the strains, with notable resistance to drugs such as erythromycin, cefoxitin, and tetracycline. The study's findings underscore the importance of integrating advanced diagnostic technologies like MALDI-TOF MS into routine environmental monitoring and public health strategies to address the challenges posed by P. aeruginosa in wastewater. Ultimately, this research contributes to understanding the dynamics of contamination and resistance in urban environments. By detailing the methodology used for the identification and characterization of the strains, as well as the results obtained, this publication aims to provide a valuable database for researchers and practitioners engaged in combating nosocomial infections and environmental pollution by P. aeruginosa. This study highlights the need for effective management measures to control the dissemination of this pathogen in aquatic systems, promoting public health and environmental safety.

Detecting and Reporting Extended Spectrum Beta-Lactamases Producers: Evaluation of Three Approaches and the Clinical Impact

Abstract Introduction/Objective Since the COVID-19 pandemic, bacteria producing extended spectrum beta-lactamases (ESBLs) have increased >30%. Laboratories can perform phenotypic microbroth dilution or molecular approaches to identify ESBL producers. However, the gold standard is a laborious double disc synergy test. We evaluated the concordance among the three approaches, the clinical impact, and justification of reporting ESBL producers. Methods/Case Report Seventy-eight ESBL producers identified by microbroth dilution (MicroScan WalkAway, Beckman Coulter, Brea, California, USA) or detection of blaCTX-M gene from blood cultures (BCID2 Panel, BioFire, Biomerieux, Salt Lake City, Utah, USA) were tested using double disc synergy test retrospectively. Concordance among the methods evaluated. Discordant cases were reviewed with subsequent patient chart review. Results (if a Case Study enter NA) Tested isolates included E. coli (n=44, 57%), K. pneumoniae (n=19, 24%), K. oxytoca (n=7, 9%), and P. mirabilis (n=8, 10%). Concordance between microbroth dilution and disk diffusion was 86% (67/78). For isolates with genotypic testing (n=16), concordance with microbroth dilution and disk diffusion was 93% and 88%, respectively. Overall concordance was 88%. There were 12 isolates (E. coli:8, P. mirabilis: 2, and K. pneumoniae:2) with discordant results from one method. The susceptibility profile of discordant isolates revealed resistance to ceftriaxone or ceftazidime (11/12), penicillin (11/12), and aztreonam (6/12); 10/12 isolates were resistant to at least 2 groups of these antibiotics, a phenotype of ESBL producers. Clinical teams acknowledged presence of ESBLs in 83% (10/12) of cases and 58% (7/12) warranted treatment with meropenem or combinational therapy. Infection prevention implemented contact isolate procedures in all cases. Conclusion Our current in-house methods (e.g., microbroth dilution and genotypic testing) are still justified for ESBL testing to optimize patient care in a timely fashion. In the minor cases with discordant results, clinical care was unaffected. Laboratory workflow changes need to take laboratory efficiency, patient outcomes, and actionable clinical changes into consideration.

Antimicrobial Resistance of Uropathogenic Escherichia coli in Outpatient Cases at Baeza Basic Hospital, Ecuador

Introduction: Bacterial resistance to antibiotics is one of the current major public health issues, as these compounds constitute a primary tool for controlling and treating bacterial infections. Objective: To determine the bacterial resistance of uropathogenic Escherichia coli in outpatient individuals attending the Microbiology Laboratory of Baeza Basic Hospital (BBH) during the period January-December 2023. Methodology: An observational, descriptive, and cross-sectional study was conducted to describe the antimicrobial resistance characteristics of uropathogenic Escherichia coli during the period January-December 2023. Results: We analyzed 169 positive urine culture results from outpatient individuals of both sexes, varying ages, with a diagnosis of urinary tract infection. The most frequently isolated microorganisms were Escherichia coli (80.1%), followed by Enterococcus faecalis (3.8%) and Proteus mirabilis (3.3%). Regarding antimicrobial resistance profiles expressed as a percentage for E. coli, they were as follows: ampicillin (70.8%), nalidixic acid (53.7%), amoxicillin + clavulanic acid (48.8%), trimethoprim + sulfamethoxazole (44.0%), and ciprofloxacin (34.3%). 12.4% of E. coli were extended-spectrum beta-lactamase (ESBL) producers. The sensitivity of E. coli to nitrofurantoin was 92.1%, ampicillin-sulbactam 90.4%, and fosfomycin 87.1%. Conclusions: The recommended empirical first-line treatment is nitrofurantoin, fosfomycin, and as second-line options, cephalexin and cefuroxime for uncomplicated urinary tract infections. Based on this information, it is proposed to develop a Clinical Guide for the treatment of uncomplicated urinary tract infections in the study areaarea.

Antimicrobial Resistance of Uropathogenic Escherichia coli in Outpatient Cases at Baeza Basic Hospital, Ecuador

Introduction: Bacterial resistance to antibiotics is one of the current major public health issues, as these compounds constitute a primary tool for controlling and treating bacterial infections. Objective: To determine the bacterial resistance of uropathogenic Escherichia coli in outpatient individuals attending the Microbiology Laboratory of Baeza Basic Hospital (BBH) during the period January-December 2023. Methodology: An observational, descriptive, and cross-sectional study was conducted to describe the antimicrobial resistance characteristics of uropathogenic Escherichia coli during the period January-December 2023. Results: We analyzed 169 positive urine culture results from outpatient individuals of both sexes, varying ages, with a diagnosis of urinary tract infection. The most frequently isolated microorganisms were Escherichia coli (80.1%), followed by Enterococcus faecalis (3.8%) and Proteus mirabilis (3.3%). Regarding antimicrobial resistance profiles expressed as a percentage for E. coli, they were as follows: ampicillin (70.8%), nalidixic acid (53.7%), amoxicillin + clavulanic acid (48.8%), trimethoprim + sulfamethoxazole (44.0%), and ciprofloxacin (34.3%). 12.4% of E. coli were extended-spectrum beta-lactamase (ESBL) producers. The sensitivity of E. coli to nitrofurantoin was 92.1%, ampicillin-sulbactam 90.4%, and fosfomycin 87.1%. Conclusions: The recommended empirical first-line treatment is nitrofurantoin, fosfomycin, and as second-line options, cephalexin and cefuroxime for uncomplicated urinary tract infections. Based on this information, it is proposed to develop a Clinical Guide for the treatment of uncomplicated urinary tract infections in the study areaarea.

Isolation and molecular characterization of multi-drug resistant uropathogenic Escherichia coli from urine samples: Insights into urinary tract infection management

Urinary tract infections (UTIs) caused by uropathogenic Escherichia coli (UPEC) present a significant global health burden. With UPEC responsible for approximately 90 % of UTIs, understanding its mechanisms of virulence and antibiotic resistance is paramount for effective treatment strategies. This study aimed to investigate the prevalence of multi-drug resistant (MDR) E. coli strains in urinary tract infections and to elucidate the molecular mechanisms underlying their resistance. A total of 150 E. coli isolates were obtained from urinary tract infection specimens collected patients at Doctor’s Diagnostic Centre in Kalyan Nagar, Bangalore over four months November 2022 to February 2023. Isolation and screening of pathogenic E. coli were conducted using Eosin Methylene Blue Agar and Nutrient Agar, followed by identification through gram staining and biochemical characterization tests. Antibiotic susceptibility testing was performed using Mueller-Hinton agar and various antibiotic discs. Phenotypic and molecular identification of extended-spectrum beta-lactamase (ESBL) producers were conducted, along with the screening for specific antibiotic resistance genes using polymerase chain reaction (PCR). Of the 150 E. coli isolates, 57.3 % were found to be multi-drug resistant, with all 35 isolates from hospitalized patients exhibiting MDR characteristics. Phenotypic and molecular analyses revealed the presence of ESBL-producing isolates, with the blaCTX-M, blaTEM, and blaSHV genes detected in PCR assays. Plasmid extraction and PCR assays further identified the presence of plasmid-encoded carbapenemase genes (blaOXA-48, blaNDM-1, blaKPC-2), as well as other antibiotic resistance genes including those conferring resistance to fluoroquinolones. The results underscore the alarming prevalence of MDR E. coli strains in urinary tract infections, particularly in hospitalized patients. Molecular characterization revealed the diverse genetic mechanisms contributing to antibiotic resistance, including the presence of ESBLs and plasmid-encoded resistance genes. These findings emphasize the urgent need for surveillance and infection control measures to mitigate the spread of MDR pathogens and the development of alternative therapeutic strategies to combat antibiotic resistance in UTIs.

A-253 Antimicrobial Susceptibility Pattern in Escherichia coli Isolated From Community-Acquired Urinary Tract Infections in the era Post-Covid-19

Abstract Background Urinary tract infections (UTI) are one of the most common infectious diseases diagnosed in the community as well as in hospitals. Community-acquired urinary tract infections caused by Escherichia coli represent the largest proportion of infectious diseases affecting women and a significant amount of oral antibiotics are prescribed daily to treat UTI in community outpatient clinics. Having knowledge of regional susceptibility data regarding E. coli is very important for selecting an appropriate empirical antibiotic. This study aimed to report the frequency and antimicrobial susceptibility of E. coli isolated from community-acquired urinary tract infections post-Covid-19 pandemic. Methods This study was a retrospective analysis from January to December 2023 based on the analysis of 24,019 uropathogens isolated from 182 outpatient health centers located in several regions of São Paulo city, Brazil. The urine samples were cultivated onto ChromID™CPS® agar plates by semi-quantitative technique using 1µL disposable loop, incubated at 35-37°C and the colony counting were read after 24h and 48h of incubation. The bacteria identification was performed by MALDI-TOF mass spectrometry (Vitek-MS), and the minimal inhibitory concentrations of antibiotics were determined using the Vitek®2 system, according to the manufacture’s recommendations. Only positive results with one bacterial species and a colony count ≥105 CFU/mL was considered for descriptive analysis. Results Of the 24,019 urine samples tested, 71.44% (17,159/24,019) were identified as Escherichia coli. The major frequency of E. coli infection occurred among women (90.48%) and the main age range was over 60 years (38.57%), while 21-30 comprised 16.5% of cases. The antimicrobial resistance profile for E. coli isolates showed 39.9% (6852/17158) of resistance to ciprofloxacin (MIC, >0.5 mg/L), 34.7% (5,921/17,075) to trimethoprim/sulfamethoxazole (MIC, >0.5 mg/L), 37.5% (6,371/17,002) to Amoxicillin/clavulanate (MIC, >8 mg/L), 8.75% (1,501/17,592) to ceftriaxone (MIC, >1 mg/L), 4.88% (837/17,138) to cefepime (MIC, >4 mg/L), 3.64% (616/16,901) to piperacillin/tazobactam (MIC, >8 mg/L), 11.07% (1,900/17,156) of gentamicin (MIC, >2 mg/L), 0.43% (74/17,158) of amikacin (MIC, >8 mg/L) and 2.23% (377/16,909) of fosfomycin (MIC, >16 mg/L). High-level of susceptibility was detected to carbapenems with 99.94% (10/17159) to ertapenem (MIC, ≤0.5 mg/L) and 99.8% (4/17,159) to meropenem (MIC, ≤2 mg/L). The rate of Extended-spectrum beta-lactamase production was 8.1% (1391/17159). Conclusions This data could be used locally with other related samples, to properly interpret significant resistance patterns and choose the most appropriate antimicrobial for empirical treatment of patients with community-acquired urinary tract infections.

Genotypic Characterisation of Carbapenemases in Clinical Isolates of Acinetobacter baumannii in a Tertiary Care Teaching Hospital of Kerala

Background: The multidrug-resistant and carbapenem-resistant Acinetobacter baumannii strains are an increasing global concern. The primary cause of carbapenem resistance in A. baumannii is production of various beta-lactamases with versatile hydrolytic capacities. The present study investigates the prevalence of different carbapenemases among clinical isolates of carbapenem-resistant A. baumannii from a tertiary care teaching hospital in Kerala, India. Methods: Non-duplicate isolates from sputum, endotracheal aspirate, pus, urine, and blood samples were included in the study. Isolate identification and antibiotic susceptibility testing of the isolates were done using vitek 2 system. A conventional polymerase chain reaction was used to detect the carbapenemase-encoding genes in the isolates. Results: A total of the 126 isolates studied, among these 105 (83.3%) isolates were from intensive care unit patients and 21(16.6%) were from non-ICU inpatients. Most of the isolates were obtained from respiratory specimens-78(61.9%) followed by pus-33(26.2%), urine-12(9.5%) and blood- 3(2.4%). The prevalence of carbapenemase genes were as follows:blaOXA-51(n=126, 100%) blaOXA-23 (n=98, 77.7%), blaOXA-58 (n=7, 5.6%), blaNDM (n=66, 52.4%), blaIMP (n=26, 20.6%), and blaVIM (n=20, 15.9%). Among the total isolates 78 (61.9%) isolates harbored metallo-beta-lactamase genes, 47(37.3%) isolates harboured a single carbapenemase gene, while 69(54.8%) isolates harbored two or more genes. Conclusion: This study reveals a higher prevalence of metallo-beta lactamases and the co-occurrence of multiple carbapenemase genes in Carbapenem resistant A. baumannii isolates.

Microbiological Profile and Antimicrobial Susceptibility Pattern of Uropathogens Isolated From Pregnant Women Attending a Tertiary Care Hospital in Central India.

Urinary tract infections (UTIs) are more common in females than males, and during pregnancy, frequency is increased due to hormonal changes affecting the anatomy and physiology. If not treated on time, complications may develop in both the mother and fetus. This study aimed to analyze the microbiological (bacterial and yeast) profile of the isolated uropathogens and their antimicrobial susceptibility. Aseptically collected urine specimens were processed by the standard loop method. Identification of uropathogens was done by standard microbiological tests, and antimicrobial susceptibility was performed as per the Clinical and Laboratory Standards Institute (CLSI) guidelines. Out of 400 study participants, UTI was detected in 26.75% (107/400) of cases. Overall, Escherichia coli (42.99%, 46/107) was the most frequently isolated uropathogen followed by Candida species (20.56%, 22/107), whereas, among gram-positive bacteria, Enterococcus faecalis (7.47%, 8/107) was the commonest. Among Enterobacterales, extended-spectrum beta-lactamase (ESBL) and AmpC beta-lactamase (AmpC) production was observed in 19.35% (12/62, eight E. coli and four Klebsiella) and 6.45% (4/62, all E. coli) isolates, respectively. However, all the gram-negative organisms showed 100% (n=70) sensitivity to carbapenems. Among staphylococci, 50% (2/4) of isolates were methicillin-resistant, and high-level aminoglycoside resistance (HLAR) was observed in 75% (6/8) of Enterococcus faecalis isolates, but all were sensitive to vancomycin, linezolid, and nitrofurantoin. Among Candida species, non-albicans Candida (NAC) species (59%, 13/22) outweigh the number of Candida albicans (41%, 9/22), with Candida tropicalis (22.72%, 5/22) being the commonest NAC. All the Candida species were susceptible to voriconazole, whereas fluconazole resistance was observed in 31.81% (7/22) of Candida isolates, with a higher percentage in NAC species (22.72%, 5/22) than in Candida albicans (9.09%, 2/22). UTIs in pregnancy are caused by a spectrum of both gram-negative bacilli and gram-positive cocci. Moreover, there is a rise of both Candida albicans and NAC species as uropathogens, with the emergence of fluconazole resistance. There is an increased prevalence of asymptomatic bacteriuria in pregnancy, which necessitates the screening of pregnant females for UTI using culture and antimicrobial susceptibility testing.

Antimicrobial resistance profile and associated factors of hospital-acquired gram-negative bacterial pathogens among hospitalized patients in northeast Ethiopia

BackgroundAntimicrobial resistance is a major global public health issue. Infections caused by resistant species are associated with higher mortality rates, longer hospital stays, medication failure, and rising medical costs. The World Health Organisation has declared multidrug resistance-associated infections as an epidemic of public health concern.ObjectiveThis study aimed to evaluate the antimicrobial resistance profile and associated factors of hospital-acquired Gram-negative bacterial pathogens among hospitalized patients in Northeast Ethiopia.Materials and methodsA health facility-based cross-sectional study was conducted among hospitalized patients from March 2021 to February 2022. About 810 clinical specimens were collected, transported, and processed from admitted patients following the standard bacteriological procedures. The clinical samples were inoculated onto blood agar, MacConkey agar, and chocolate agar. Furthermore, the species identification was done using gram reactions, colony morphology, and color and biochemical tests. Antimicrobial susceptibility tests, extended-spectrum beta-lactamase, and carbapenemase production were performed as per the clinical laboratory standard institute guidelines. For analysis, the information was entered into Epi-data and exported to SPSS. A P value of < 0.05 with a 95% confidence interval was considered as a statistically significant association.ResultsOut of 810 clinical specimens, 285/810 (35.2%) developed bacterial infections. From the isolated bacteria, E. coli was the predominant bacteria accounting for 78/285 (27.4%) followed by K. pneumoniae, 69/285(24.42%), whereas P. vulgaris accounted for the least, 7/285 (2.5%). Overall, 132/285 (46.3%) and 99/285 (34.7%) of culture-positive patients were infected by extended-spectrum beta-lactamase and carbapenemase-producing bacteria. The overall multidrug resistance rate of the isolated bacteria was 89.4%. The highest antibiotic resistance rates were detected for doxycycline (92.9%), amoxicillin-clavulanic acid (83.9%), and ampicillin (93%). The least antibiotic resistance rate was observed for meropenem at 41.1% and amikacin at 1.7%, respectively.Conclusions and recommendationsIn the study area, significant health concerns include a range of hospital-acquired bacterial infections associated with elevated rates of multidrug resistance, Extended-spectrum beta-lactamase (ESBL), and carbapenemase-producing bacterial pathogens. Consequently, it is recommended to conduct drug-susceptibility testing of isolates and molecular detection at a national level to optimize antibiotic usage for treating prevalent bacterial infections in this area.

Beta-Lactamase production and antibiotic susceptibility screening of Staphylococus aureus isolated from ready to eat fruits sold in some parts of Offa Metropolis, Nigeria

The global menace of community-acquired antibiotic resistance of Beta Lactamase-producing Staphylococcus aureus has been traced to the increased consumption of Ready-to-eat Foods/Fruits. Samples each of ready-to-eat whole and sliced fruits (sliced pawpaw, apple, sliced watermelon, garden egg, cucumber, pear, guava, sliced coconut, berry and date fruit) were collected randomly from vendors in Offa, Kwara State, in Nigeria. Isolation and characterization of Staphylococcus aureus from the samples were done. The isolates were screened for Beta-Lactamase production and susceptibility to some antibiotics using standard microbiological techniques. A total of twenty-two (Twenty coagulase-positive and two coagulase-negative) Staphylococcus aureus was isolated. The total Staphylococal count was highest in sliced pawpaw (23.30 ± 2.75 × 10⁵ cfu/g) while the least was recorded in apple (3.0 ± 0.01 × 10⁵ cfu /g). Twenty (20) of the isolates were recorded to be Beta Lactamase producers. All the Beta Lactamase producers were 100 % resistant to Aztreoname, 80 % to Amoxicillin Clavulate, 45 and 35 % to Ceftazidine and Ceftriaxone. Thirty percent of the isolates were found to be susceptible to Ceftazidine only while 25 % were susceptible to Ceftriaxone only. The study concluded that increased incidence of Community-Acquired Multidrug-Resistant Staphylococcus aureus could be traceable to the consumption of unhygienic processed Ready-to-eat Fruits. The ripple effects of which could be dangerous to human health.

Raw meat diets are a major risk factor for carriage of third-generation cephalosporin-resistant and multidrug-resistant E. coli by dogs in the UK.

Raw-meat diets (RMD) for dogs, comprising unprocessed or non-heat-treated animal material, are increasingly popular. However, RMDs have been demonstrated to be contaminated with antimicrobial resistant (AMR) bacteria, and there is concern that such diets may pose a zoonotic disease risk. Additionally, dogs fed RMD may shed more AMR- fecal bacteria compared to those fed conventional cooked diets. Data from the UK remain limited; the present study investigated the presence of AMR-Escherichia coli in the feces of RMD and non-RMD (NRMD)-fed dogs in the UK, the E. coli AMR gene complement, and the lifestyle risk factors associated with AMR- E. coli carriage. Fecal samples from UK-owned dogs (N = 193 RMD, N = 239 NRMD) and questionnaires discussing lifestyle factors, were obtained between October 2020-August 2021. Samples underwent culture and antimicrobial susceptibility testing to determine the presence of AMR-E. coli. Whole genome sequencing determined AMR gene carriage. Risk factors for the presence of AMR-E. coli were determined by multivariable modeling. RMD dogs carried significantly more fecal AMR E. coli (p < 0.001), including third-generation cephalosporin resistant, extended-spectrum beta-lactamase (ESBL) producing, and multidrug resistant isolates and multivariable modeling confirmed raw-meat diets to be a significant risk factor. The bla CTX-M-15 gene was the most frequently identified bla ESBL gene. The bla CTX-M-55 and bla SHV-66 genes were also prevalent and were only found in RMD dogs. The mobile colistin resistance gene, mcr-4 was identified in one ESBL-producing E. coli isolate from a NRMD-fed dog. This study has shown that dogs fed RMD in the UK are significantly more likely to shed E. coli which is resistant to highest priority critically important antibiotics, and multidrug resistant E. coli, than dogs fed NRMD. Additionally, AMR-E. coli isolates from RMD-fed dogs harbor multiple, diverse, and novel AMR genes. Therefore, provision of RMD to dogs could pose an important potential threat to human and animal health, especially given the close nature of the relationship many owners share with their pets. Awareness of these findings should be shared with pet owners, veterinary and medical professionals, pet food manufacturers and public health to mitigate potential risks.

Clinical and Microbiological Study of Intra-Abdominal Infections in a Tertiary Care Hospital

Intra-abdominal infections (IAIs) are one of the important contributors to sepsis in intensive care units. The emergence of antibiotic resistance and the diversification of etiological agents make it challenging to determine the optimal empirical therapy. This study attempts to know the etiological agents, their antibiotic susceptibility patterns, and the risk factors associated with IAIs in different settings. This prospective cross-sectional study was conducted in a tertiary care facility from January 2023 to June 2023. Adult and paediatric patients having primary IAI or developed infections during their hospital stay were included in this study. Specimen like peritoneal swabs or fluid from intra-abdominal drains placed for more than 24 hours were excluded. Matrix-assisted Laser Desorption/Ionization Time-Of-Flight was used to identify the etiological agents. Vitek®2 system was used to perform the antimicrobial susceptibility. Associated risk factors were documented. A total of 86 cases were analysed. The majority of the patients had complicated IAIs (95.3%), and 65.12 % acquired the infection in the community (CA-IAI). The vast number of cases presented with intra-abdominal abscesses (46.5%). Diabetes and hepatic disorders were the frequent underlying comorbid conditions associated with CA-IAIs. Prolonged hospital stay and the presence of concomitant conditions like malignancy and chronic renal failure significantly influenced the occurrence of hospital-acquired infections (HA-IAIs). E. coli was the frequently isolated Gram-negative pathogen both in the community and hospital settings. Whereas among Gram-positives, Enterococcus predominated and was commonly isolated from HA-IAIs. Enterobacterales were highly susceptible to meropenem and piperacillin-tazobactam. E. coli and Klebsiella were the frequent extended-spectrum beta-lactamase producers and showed the least susceptibility towards cephalosporins and fluoroquinolones. Multidrug-resistant organisms (MDROs) (p=.013), including carbapenem-resistant strains (p=.048), were significantly isolated from hospital-acquired IAIs. The high prevalence of IAIs with MDROs in hospital settings emphasizes the importance of developing hospital-based antibiotic policy, infection control measures, and judicious use of antibiotics.

Green Tea Catechin Epigallocatechin Gallate Inhibits Vegetative Cell Outgrowth and Expression of Beta-Lactamase Genes in Penicillin-Resistant Bacillus anthracis Strain PCr.

The green tea catechin epigallocatechin gallate (EGCg) has antimicrobial effects on many bacteria. In this study, we investigated the inhibitory effects of EGCg on Bacillus anthracis spores and vegetative cells. The B. anthracis spores were insensitive to EGCg, but the growth of vegetative cells derived from germinated spores was inhibited by EGCg. Moreover, EGCg decreased the minimum inhibitory concentration of penicillin and meropenem for penicillin-resistant B. anthracis. In the penicillin-resistant B. anthracis strain, the transcription levels of the beta-lactamase genes (bla1 and bla2) decreased significantly following the treatment with 50 µg/mL EGCg. These results suggest that the appropriate application of EGCg may effectively control the penicillin-resistant B. anthracis growth and beta-lactamase production.

Antibiotic Resistance & Extended-Spectrum ß-Lactamase Production in Clinical and Non-Clinical Isolates in Tabuk.

The increasing prevalence of antibiotic resistance, driven by the production of extended-spectrum beta-lactamases (ESBLs), presents a critical challenge to current medical treatments, particularly in clinical settings. Understanding the distribution and frequency of ESBL-producing bacteria is essential for developing effective control strategies. This study investigated the antibiotic resistance and extended-spectrum beta-lactamase (ESBL) production in bacterial isolates in clinical and non-clinical (food) specimens in Tabuk, KSA. A total of 57 bacterial isolates were analysed, with E. coli and Pseudomonas sp. being the most prevalent. High resistance rates were observed, particularly against third-generation cephalosporins in clinical isolates. ESBL screening revealed a significant prevalence in clinical samples (58.3%), with E. coli showing the highest positivity. Conversely, only a low percentage of food isolates were ESBL positive. Molecular analysis confirmed the presence of various ESBL genes, with blaCTX-M being the most frequent, predominantly found in clinical isolates. This study highlights the concerning levels of antibiotic resistance and ESBL production in the region, emphasising the need for effective infection control measures and prudent antibiotic use.

SHEDDING LIGHT ON GENETIC RELATIONSHIPS, PLASMID PROFILES AND ANTIBIOTIC RESISTANCE PATTERNS OF CLINICAL ESCHERICHIA COLI STRAINS: PULSED-FIELD GEL ELECTROPHORESIS PERSPECTIVE

In the present work, 47 Escherichia coli isolates collected from various clinical samples were elucidated with regard to genetic relationship, antibiotic resistance and plasmid profile. The genetic diversity of the isolates was defined by the pulsed field gel electrophoresis (PFGE) method. With a degree of similarity of 80%, the results from PFGE separated the E. coli strains into 39 different groups representing four subtypes. Antibiotic resistance patterns and extended spectrum of beta lactamase (ESBL) producing properties of the strains were determined by using a disk diffusion and double disc synergy method, respectively. According to the susceptibility test results, 36 distinct resistance profiles (resisto type) were observed among clinical strains. The strains were mostly resistant to ampicillin (100%) and this has been followed by cephalothin and ticarcillin/clavulanic acid with the ratio of 89.36%, cefuroxime with the ratio of 87.24%, tetracycline and cefotaxime with the ratio of 80.85%. It was observed that 24 of the strains (51.06%) were defined as ESBL positive. When E. coli strains were evaluated according to plasmid size, it was determined that 27 of 47 strains (57.44%) carried plasmids and the sizes of the determined plasmids were ranging between 77.1 kb and 1.6 kb. It was concluded that plasmids of E. coli strains are randomly distributed and no significant correlation was found between antibiotic resistance patterns and plasmids.

Extended spectrum and metalo beta lactamase producing gram negative bacterial pathogens from cockroaches collected at hospital, Southern Ethiopia

BackgroundCockroaches can pose a significant health risk in hospital environments because they may serve as reservoirs and vectors for nosocomial pathogens. Cockroaches harbor epidemiologically significant extended spectrum and metalo beta lactamase producing Gram negative bacterial pathogens, which complicate nosocomial infections.ObjectivesThe main aim of this study is to determine aetiology and phenotypic extended spectrum and metalo beta lactamase producing Gram negative bacteria pathogens from cockroaches collected in hospitals.MethodsA cross-sectional study was employed from February to May 2022 to determine the antibiotic resistance producing bacterial isolates from cockroaches by giving special emphasis to metalo beta lactamase and extended spectrum beta lactamase production from different wards of WSUCSH. Cockroaches were collected with hands wearing sterile gloves. External homogenate was prepared and incubated microbiologically by using different culture media and differentiated biochemically. Antimicrobial susceptibility testing was performed by disk diffusion method. ESBL production was conducted using double disc synergy method and double disk method was used to detect MBL enzyme detection. Descriptive statistics was used to determine prevalence and percentage.ResultOut of 245 cockroaches, 108 Gram negative bacteria were isolated. K. pneumoniae 29(26.9%) was the most predominant bacteria and Enetrobacter spp. 8(7.4%), was the least. All, K. pneumoniae, P. mirabilis, and Enterobacter isolates were pan-resistant to Ampicillin. P.aeruginosa and P.mirabilis antibiotics showed ≥ 80% resistant for amoxicillin/clavulanic acid antibiotics. Cefotaxime, ceftazidime, ceftriaxone and imipenem showed relative efficacy compared with other antibiotics. Out of 78 amoxicillin-clavulanic acid resistant isolates, 42(34.7%) were ESBL producers. ESBL production is more depicted by P. aeruginosa, A. baumannii, K. pneumoniae and E. coli. The overall prevalence of MBL production is 29(23.1%). K. pneumoniae P. aeruginosa, E.coli, A. baumannii, Enterobacter spp and K.oxytoca revealed MBL production.ConclusionThe overall prevalence of ESBL and MBL producing nosocomial agents from hospital cockroaches was 34.7% and 23.1% respectively. P.aeruginosa, A.baumannii, K.pneumoniae and E.coli showed pronounced ESBL production. All bacterial isolates except P. mirabilis and C. freundii showed MBL production. The needed to evaluate our antibiotic stewardship program and antibiotic resistance detection for treatment is mandatory. The impact of cockroach as a source of AMR should be sought.

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.

Extended-spectrum beta-lactamase (ESBL) production and virulence genes profile of avian pathogenic Escherichia coli (APEC) isolated from broiler chickens in eastern Thailand

Avian pathogenic Escherichia coli (APEC) causes colibacillosis, resulting in extensive economic losses for the broiler industry. To date, there is little information in Thailand about virulence-associated genes and antibiotic resistance of APEC strains. Here, this study aimed to investigate the virulence genes and extended-spectrum beta-lactamase (ESBL) characteristics of APEC isolated from broilers. This study used multiplex polymerase chain reaction (PCR) to determine the presence of virulence genes and resistance genes in APEC. Furthermore, the disc diffusion method examined ESBL phenotypes of APEC and antibiotic resistance profiles against 17 antimicrobials. In this study, E. coli was isolated 11 (6.32%) of 174 broiler visceral organs. All E. coli isolates were tested for five APEC-virulence-associated genes (iroN, ompT, hlyF, iutA, and iss). Eight E. coli isolates from broilers with colibacillosis-associated lesions carried two (iroN and ompT) of the APEC virulence genes. One APEC virulence gene (hlyF) was found in E. coli isolates from broilers without lesions. Possibly no individual virulence gene was specific to the APEC strain. Interestingly, the papC, previously detected in humans with uropathogenic E. coli, was found in an APEC isolate. All APEC isolates were ESBL-producing E. coli, and then they were tested for four beta-lactamase-encoding genes (blaTEM, blaCTX-M, blaOXA, and blaSHV). The blaTEM and blaCTX-M were identified in 81.81% (9/11) of the isolates, whereas blaOXA or blaSHV were not detected in any isolate. All APEC showed multi-drug resistance (MDR) phenotypes, especially chloramphenicol, erythromycin, and sulfamethoxazole-trimethoprim. Although antibiotics were not recently used, MDR might be encouraged by horizontally transferring antibiotic-resistance genes. In addition, fluoroquinolone resistances were found in APEC isolates which could transfer resistance genes to humans via the food chain. This study indicates that APEC isolates contain several virulence and bla genes and should be surveillance to prevent the transmission of those genes to humans.