Antibiotic susceptibility and high prevalence of extended spectrum beta-lactamase producing Escherichia coli in iranian broilers

Extended-spectrum β-lactamase (ESBL) producing Escherichia coli have rapidly spread worldwide and cause serious threats for public health. The study was conducted to determine the antibiotic resistance and characterization of ESBL producing E. coli strains isolated from broilers in Northern Iran. Antibiotic susceptibility test was done for a total of 100 isolates of E. coli, recovered from 240 broiler fecal samples at the slaughterhouse stage. ESBL production was screened using double-disc synergy test (DDST) and presence of four ESBL genes including blaPER, blaVEB, blaTEM and blaCTX-M was tested using PCR. Among 100 strains isolated from broilers, 53 were identified as ESBL-producing E. coli. All (100) ESBL positive isolates were typed according to the presence of one or two ESBL-associated genes. The most prevalent gene among ESBLs was CTX-M (60.3) and the PER gene was not present among isolates. All isolates in this study were resistant to colistin and nalidixic acid but were 100 sensitive to cefalexin and furazolidone. The results demonstrated the high prevalence of antibiotic resistant and ESBL producing E. coli among broilers which representing the risk of increasing these strains in human infections associated with food animals

Assessing the occurrence and transfer dynamics of ESBL/pAmpC-producing Escherichia coli across the broiler production pyramid

Extended-spectrum \u3b2-lactamase (ESBL)- and plasmid mediated AmpC-type cephalosporinase (pAmpC)-producing Escherichia coli (ESBL/pAmpC E. coli) in food-producing animals is a major public health concern. This study aimed at quantifying ESBL/pAmpC-E. coli occurrence and transfer in Italy's broiler production pyramid. Three production chains of an integrated broiler company were investigated. Cloacal swabs were taken from parent stock chickens and offspring broiler flocks in four fattening farms per chain. Carcasses from sampled broiler flocks were collected at slaughterhouse. Samples were processed on selective media, and E. coli colonies were screened for ESBL/pAmpC production. ESBL/pAmpC genes and E. coli phylogroups were determined by PCR and sequencing. Average pairwise overlap of ESBL/pAmpC E. coli gene and phylogroup occurrences between subsequent production stages was estimated using the proportional similarity index, modelling uncertainty in a Monte Carlo simulation setting. In total, 820 samples were processed, from which 513 ESBL/pAmpC E. coli isolates were obtained. We found a high prevalence (92.5%, 95%CI 72.1-98.3%) in day-old parent stock chicks, in which blaCMY-2 predominated; prevalence then dropped to 20% (12.9-29.6%) at laying phase. In fattening broilers, prevalence was 69.2% (53.6-81.3%) at the start of production, 54.2% (38.9-68.6%) at slaughter time, and 61.3% (48.1-72.9%) in carcasses. Significantly decreasing and increasing trends for respectively blaCMY-2 and blaCTX-M-1 gene occurrences were found across subsequent production stages. ESBL/pAmpC E. coli genetic background appeared complex and bla-gene/phylogroup associations indicated clonal and horizontal transmission. Modelling revealed that the average transfer of ESBL/pAmpC E. coli genes between subsequent production stages was 47.7% (42.3-53.4%). We concluded that ESBL/pAmpC E. coli in the broiler production pyramid is prevalent, with substantial transfer between subsequent production levels

Preliminary Analysis of the Anti-biofilm Efficacy of Manuka Honey on Extended Spectrum Β-lactamase Producing Escherichia Coli Tem-3 and Klebsiella Pneumoniae Shv18, Associated with Urinary Tract Infections

open access articleUrinary Tract Infections (UTIs) are one of the most common infections in the UK and many other parts of the world. The prevalence of the Extended Spectrum β-Lactamases (ESBLs) producing UTIs, combined with their ability to form a bio film, has significantly risen and is limiting therapeutic options. This study investigated the anti-bio film activity of Manuka honey on two ESBL producing pathogens, Escherichia coli TEM-3 and Klebsiella pneumonia SHV18, commonly found in UTIs. The ESBL production was confirmed by the double disk synergy method used to confirm the ESBL production. The antibacterial activity of Manuka honey was determined using the agar well diffusion method. The Minimum Inhibitory Concentration (MIC) was established using serially diluted honey ranging from 50% to 1.56%. The effect of Manuka honey on the pathogen bio films was analysed using the Tissue Culture Plate method, with an established MIC and under 24h incubation with the honey. The results indicated that K. pneumonia SHV18 is a stronger bio film producer than E. coli TEM 3. 50% (w/v) MIC Manuka honey appears to fully prevent the plank tonic growth of both strains. A significant reduction of 81% of the E. coli TEM3 (p < 0.001) and 52% of the K. pneumonia SHV18 (p = 0.001) bio film biomass was observed. The E. coli bio films were found to be more sensitive to the 50% (w/v) honey dilution than those produced by K. pneumonia. The study indicated the anti-bio film potency of Manuka honey and its potential to become an alternative treatment for the ESBL producing pathogens associated with UTIs

The Distribution of ESBL-Producing Enterobacteriaceae: Leicestershire UK Compared to Worldwide

open access articl

Detection of extended spectrum B-lactamases in urinary isolates of Klebsiella pneumoniae in relation to Bla SHV, Bla TEM and Bla CTX-M gene carriage

Background: Resistance to contemporary broad-spectrum β-lactam antibiotics mediated by extended-spectrum β-lactamases (ESBLs) is increasing worldwide. Klebsiella pneumoniae, an important cause of nosocomial and community acquired urinary tract infections has rapidly become the most common ESBL producing organism. We examined ESBL production in urinary isolates of K. pneumoniae in relation to the presence of bla SHV, bla TEM and bla CTX-M genes. Methods: Antibiotic resistance of 51 clinical isolates of K. pneumoniae was determined to amoxicillin, amikacin, ceftazidime, cefotaxime, cefteriaxon, ceftizoxime, gentamicin, ciprofloxacin and nitrofurantoin by disc diffusion. Minimum inhibitory concentrations were also measured for ceftazidime, cefotaxime, cefteriaxon, ceftizoxime and ciprofloxacin. ESBL production was detected by the double disc synergy test and finally, presence of the bla SHV, bla TEM and bla CTX-M genes were shown using specific primers and PCR. Results: Disc diffusion results showed that 96.08 % of the isolates were resistant to amoxicillin followed by 78.43 % resistance to nitrofurantoin, 49.02 % to amikacin and ceftazidime, 41.17 % to ceftriaxone, 37.25% resistance to cefotaxime and ceftizoxime, and 29.42 % to gentamicin and ciprofloxacin. Both resistant and intermediately resistant organisms were resistant in MIC determinations. Twenty two isolates (43.14%) carried bla SHV, 18 (35.29%) had bla TEM and 16 (31.37%) harbored bla CTX-M genes. ESBL production was present in 14 isolates (27.45 %) of which, 3 did not harbor any of the 3 genes. Among the non- ESBL producers, 9 lacked all 3 genes and 2 carried them all. Conclusion: No relation was found between gene presence and ESBL expression

Impact of short-term storage on the quantity of extended-spectrum beta-lactamase–producing Escherichia coli in broiler litter under practical conditions

Applying broiler litter containing extended-spectrum beta-lactamase (ESBL)–producing Escherichia coli (E. coli) to arable land poses a potential risk for humans to get colonized by contact with contaminated soil or vegetables. Therefore, an inactivation of these bacteria before land application of litter is crucial. We performed 2 short-term litter storage trials (one in summer and winter, respectively), each covering a time span of 5 D to investigate the effectiveness of this method for inactivation of ESBL-producing E. coli in chicken litter. Surface and deep litter samples were taken from a stacked, ESBL-positive chicken litter heap in triplicates in close sampling intervals at the beginning and daily for the last 3 D of the experiments. Samples were analyzed quantitatively and qualitatively for ESBL-producing E. coli, total E. coli, and enterococci. Selected isolates were further characterized by whole-genome sequencing (WGS). In the depth of the heap ESBL-producing E. coli were detected quantitatively until 72 h and qualitatively until the end of the trial in winter. In summer detection was possible quantitatively up to 36 h and qualitatively until 72 h. For surface litter samples a qualitative detection of ESBL-producing E. coli was possible in all samples taken in both trials. In the deep samples a significant decrease in the bacterial counts of over 2 Log10 was observed for total E. coli in the winter and for total E. coli and enterococci in the summer. Genetic differences of the isolates analyzed by WGS did not correlate with survival advantage. In conclusion, short-term storage of chicken litter stacked in heaps is a useful tool for the reduction of bacterial counts including ESBL-producing E. coli. However, incomplete inactivation was observed at the surface of the heap and at low ambient temperatures. Therefore, an extension of the storage period in winter as well as turning of the heap to provide aerobic composting conditions should be considered if working and storage capacities are available on the farms

Wild birds as carriers of antimicrobial-resistant and ESBL-producing Enterobacteriaceae

open6noopenDotto, G.; Menandro, M.L.; Mondin, A.; Martini, M.; Tonellato, F.R.; Pasotto, D.Dotto, Giorgia; Menandro, MARIA LUISA; Mondin, Alessandra; Martini, Marco; Tonellato, F. R.; Pasotto, Daniel

Characterization of extended-spectrum β-lactamases produced by Escherichia coli isolated from hospitalized and nonhospitalized patients : emergence of CTX-M-15-producing strains causing urinary tract infections

Extended-spectrum β-lactamase-producing Escherichia coli isolates were obtained from hospitalised and non-hospitalised patients in Belgium between August 2006 and November 2007. The antimicrobial susceptibility of these isolates was determined and their ESBL genes were characterized. Clonal relationships between the CTX-M-producing E. coli isolates causing urinary tract infections were also studied. A total of 90 hospital- and 45 community-acquired cephalosporin-resistant E. coli isolates were obtained. Tetracycline, enrofloxacine, gentamicin and trimethoprim-sulfamethaxozole resistance rates were significantly different between the community-onset and hospital-acquired isolates. A high diversity of different ESBLs was observed among the hospital-acquired E. coli isolates whereas CTX-M-15 was dominating among the community-acquired E. coli isolates (n=28). Thirtheen different PFGE profiles were observed in the community-acquired CTX-M-15-producing E. coli indicating that multiple clones have acquired the blaCTX-M-15 gene. All community-acquired CTX-M-15-producing E. coli isolates of phylogroups B2 and D were assigned to the sequence type ST131. The hospital-acquired CTX-M-15-producing E. coli isolates of phylogroups B2, B1, A and D corresponded to ST131, ST617, ST48 and ST405, respectively. In conclusion, CTX-M-type ESBLs have emerged as the predominant class of ESBLs produced by E. coli isolates in the hospital and community in Belgium. Of particular concern is the predominant presence of the CTX-M-15 enzyme in ST131 community-acquired E. coli

Broad-spectrum β-lactamases among Enterobacteriaceae of animal origin: molecular aspects, mobility and impact on public health

Broad-spectrum β-lactamase genes (coding for extended-spectrum β-lactamases (ESBLs) and AmpC β-lactamases) have been frequently demonstrated in the microbiota of food-producing animals. This may pose a human health hazard since these genes may be present in zoonotic bacteria, which would cause a direct problem. They can also be present in commensals, which may act as a reservoir of resistance genes for pathogens causing disease both in humans and animals. Broad-spectrum β-lactamase genes are frequently located on mobile genetic elements, such as plasmids, transposons and integrons, which often also carry additional resistance genes. This could limit treatment options for infections caused by broad-spectrum β-lactam-resistant microorganisms. This review addresses the growing burden of broad-spectrum β-lactam resistance among Enterobacteriaceae isolated from food, companion and wild animals worldwide. To explore the human health hazard, the diversity of broad-spectrum β-lactamases among Enterobacteriaceae derived from animals is compared with respect to their presence in human bacteria. Furthermore, the possibilities of the exchange of genes encoding broad-spectrum β-lactamases – including the exchange of the transposons and plasmids that serve as vehicles for these genes – between different ecosystems (human and animal) are discussed