Objectives Fast and adequate detection of extended-spectrum b-lactamases (ESBLs) is crucial for infection control measures and the choice of antimicrobial therapy. The aim of this study was to ...develop and evaluate a novel ESBL assay using ligation-mediated amplification combined with microarray analysis to detect the most prevalent ESBLs in Enterobacteriaceae: TEM, SHV and CTX-M. Methods Analysis of the Lahey database revealed that the vast majority of TEM and SHV ESBLs differ from non-ESBL variants in three amino acid positions. TEM ESBLs have at least one of the following amino acid substitutions: R164S/H/C, G238D/N/S and E104K. In SHV ESBLs, one or more of the following substitutions is observed: D179A/N/G, G238S/A and E240K. Oligonucleotide probes were designed to detect these substitutions, covering 95% of ESBL TEM variants and 77% of ESBL SHV variants. In addition, probes were designed to distinguish between CTX-M groups 1, 2, 9 and 8/25. For evaluation of the assay, 212 Enterobacteriaceae isolates with various b-lactamases were included (n=106 ESBL positive). Results The sensitivity of the microarray was 101/106 (95%; 95% CI 89%-98%), and the specificity 100% (95% CI 97%-100%) using molecular characterization of ESBLs by PCR and sequencing as reference. Assay performance time was 8 h for 36 isolates. Conclusions This novel commercially available DNA microarray system may offer an attractive option for rapid and accurate detection of CTX-M, TEM and SHV ESBL genes in Enterobacteriaceae in the clinical laboratory.
Foodstuffs are a well-documented source of multidrug-resistant bacteria, and hospitalized patients are usually susceptible to hospital infections owing to their immune status. Therefore, this study ...aimed to investigate the presence of beta-lactamase-producing Enterobacterales in ready-to-eat foods consumed by hospitalized patients. For this purpose, 51 vegetable and meat samples were collected over 2 months and analyzed. Enterobacterales isolates were identified and subjected to antimicrobial susceptibility testing, followed by beta-lactamase gene screening, pH tolerance assays, and whole-genome sequencing (WGS). Isolates harboring genes encoding extended-spectrum beta-lactamases, cephalosporinases, or carbapenemases were detected, and all isolates tolerated pH levels similar to those in the human gastrointestinal tract. The blaKPC-2 carriers were characterized by WGS and lineages closely related to those causing human infections were identified. These results showed that dietary intake is an alternative route for the transmission of antimicrobial-resistant bacteria, which must be considered when designing effective strategies for infection control.
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•Multidrug-resistant Enterobacterales were isolated from food served to patients.•Isolates tolerate the pH conditions of the human gastrointestinal tract.•A Klebsiella michiganensis isolate ST451 presented blaKPC-2 in an IncN2 plasmid.•KPC-2-producing Enterobacter hormaechei isolates ST114 and ST269 were also detected.•Carbapenemase producing isolates were identified as potential pathogens.
•Cefepime/enmetazobactam (FEN), a new ß-lactam/ß-lactamase inhibitor was evaluated.•97.9% of Enterobacterales isolates from Europe were susceptible to FEN (FEN-S).•Most third-generation ...cephalosporin-resistant isolates were ESBL-pos and FEN-S.•Most meropenem-non-susceptible isolates carrying OXA-48 (9/12) were FEN-S.•FEN could be used as a carbapenem sparing agent to replace piperacillin/tazobactam.
This study was performed to investigate the activity of the novel ß-lactam/ß-lactamase inhibitor combination cefepime/enmetazobactam, against recently circulating Enterobacterales isolates from Europe from 2019 to 2021.
A total of 2627 isolates were collected, and antimicrobial susceptibility was determined according to the European Committee on Antimicrobial Susceptibility Testing guidelines. Isolates with phenotypic resistance to ceftriaxone and ceftazidime (but susceptible to meropenem) and isolates nonsusceptible to meropenem were screened for the presence of ß-lactamases.
Overall, susceptibility to third-generation cephalosporins was 77%, and 97.3% were susceptible to meropenem. Cefepime/enmetazobactam susceptibility was 97.9% (72% of these isolates were Klebsiella pneumoniae from Italy), compared with 80.0% susceptibility to piperacillin/tazobactam and 99.4% to ceftazidime/avibactam. A total of 320 isolates (12.2%) were resistant to third-generation cephalosporins but susceptible to meropenem, and virtually all (96.3%) carried an extended-spectrum ß-lactamase with or without an AmpC and these were all susceptible to cefepime/enmetazobactam. Most meropenem-nonsusceptible isolates carried a KPC (68%), which were not inhibited by cefepime/enmetazobactam but were inhibited by ceftazidime/avibactam. Additionally, most meropenem-nonsusceptible isolates carrying OXA-48 (9/12 isolates) were susceptible to cefepime/enmetazobactam.
Cefepime/enmetazobactam was highly active against Enterobacterales isolates, especially those resistant to third-generation cephalosporins. These data suggest that cefepime/enmetazobactam could be used as a carbapenem-sparing agent to replace piperacillin/tazobactam.
Abstract Objective The objective of this study was to determine the proportion of extended spectrum β-lactamase producing gram-negative bacteria (ESBL-GNB) colonizing patients admitted at Mazimbu ...hospital and Morogoro Regional hospital, in Morogoro, Tanzania. Rectal colonization with ESBL-GNB increases the risks of developing bacterial infections by extra-intestinal pathogenic ESBL-GNB. Results Of the 285 patients investigated, 123 (43.2%) carried ESBL-GNB in their intestines. Five of the 123 ESBL positive patients were colonized with two different bacteria, making a total of 128 ESBL producing isolates. Escherichia coli (n = 95, 74.2%) formed the majority of ESBL isolates. The proportion of CTX-M-1 group genes among ESBL isolates tested was 94.9% (93/98). History of antibiotic use (OR: 1.83, 95% CI: 1.1–3.2, P = 0.03), being on antibiotic treatment (OR: 2.61, 95% CI: 1.5–4.53, P = 0.001), duration of hospital stay (OR: 1.2, 95% CI: 1.1–1.3, P < 0.001) and history of previous admission (OR: 2.24, 95% CI: 1.2–4.1, P = 0.009) independently predicted ESBL-GNB carriage.
A prospective cohort study was performed among travelers from the Netherlands to investigate the acquisition of carbapenemase-producing
Enterobacteriaceae
(CP-E) and extended-spectrum ...β-lactamase–producing
Enterobacteriaceae
(ESBL-E) and associated risk factors. Questionnaires were administered and rectal swab samples were collected and tested before and after traveler return. Of 370 travelers, 32 (8.6%) were colonized with ESBL-E before trave,; 113 (30.5%) acquired an ESBL-E during travel, and 26 were still colonized 6 months after return. No CP-E were found. Independent risk factors for ESBL-E acquisition were travel to South and East Asia. Multilocus sequence typing showed extensive genetic diversity among
Escherichia coli
. Predominant ESBLs were CTX-M enzymes. The acquisition rate, 30.5%, of ESBL-E in travelers from the Netherlands to all destinations studied was high. Active surveillance for ESBL-E and CP-E and contact isolation precautions may be recommended at admission to medical facilities for patients who traveled to Asia during the previous 6 months.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, ODKLJ, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The increasing incidence of intestinal colonization with extended-spectrum β-lactamase (ESBL)-producing Enterobacteriaceae and Gram negative organisms that has been observed in food animals such as ...poultry, cattle and pigs, are suggestive that animals, food and environment are potential sources of ESBL-producing bacteria. Hence, the aim of this study was to characterized commensal E. coli obtained from healthy broiler and turkey flocks at slaughter for the presence of penicillinases-, ESBL-, extended-spectrum AmpC (ESAC)-, plasmid-mediated quinolone resistance- and MCR-encoding genes. Study of clonal relatedness showed genetic diversity among CTX-M-type, SHV-12 and TEM-52 producing isolates with human isolates of the same type, was also assessed. We detected that eleven (5.4%, 11/202) and forty-five (2.2%, 45/185) E. coli isolates from broilers and turkeys, respectively, carried blaESBL or blaESAC genes and two isolates from turkeys carried mcr-1 gene. A new variant blaCTX-M-166 was reported in a multidrug resistant isolate from a broiler flock. Overall, we detected a diversity of resistance mechanisms among E. coli from food-producing animals, all of them with high importance at a public health level.
•Detection of blaESBL, blaESAC and the recently described mcr-1 gene.•New variant blaCTX-M-166 reported in a MDR isolate from a broiler flock.•WGS approach revealed a CTX-M-166-harboring O6:H16 ST48-fimH34 E. coli.•ESBL-producing E. coli in the poultry population was not due to one specific clone.
Enterobacter cloacae complex (ECC) members are rapidly emerging as successful nosocomial pathogens, especially, with the emergence of carbapenem-resistant clones. In this study, we performed a ...comprehensive molecular characterization of a carbapenem-resistant E. hormaechei ssp. xiangfangensis LAU_ENC1. hsp60 and average nucleotide identity (ANI) were used for its identification. The repertoire of resistance genes and phage content were analyzed. Plasmid sequences were extracted and compared to closest references. The isolate LAU_ENC1 was identified as an E. hormaechei ssp. xiangfangensis and belonged to ST-114A sub-cluster. blaNDM-1, blaCTX-M-15, blaOXA-1, and blaACT-16 genes were detected as β-lactam resistance determinants. A chromosomal hybrid intact phage, Enterobacter phage LAU1, with blaCTX-M-15 integrated in its direct vicinity within an ISEcp1 - blaCTX-M-15 - wbuC - ∆Tn2 rare cassette was detected. blaNDM-1 was integrated within a novel IncFII conjugative plasmid, pLAU_ENC1, through an IS3000- ΔISAba125-blaNDM-1-bleMBL−//−Tn5403 cassette. To our knowledge, this is the first report of a multi-drug resistant (MDR) E. hormaechei ssp. xiangfangensis carrying a blaCTX-M-15 integrated within the proximity of a provirus chromosomal region. Treatment options for MDR ECC members are becoming scarce, thus warranting an increased monitoring of the dissemination of these pathogens in clinical settings.
•Genome characterization of MDR Enterobacter hormaechei ssp. Xiangfangensis (LAU_ENC1)•LAU_ENC1 belongs to ST-1144 sub-cluster co-harbouring blaNDM-1 and a Chromosomally encoded phage-linked blaCTX-M-15 genes.•blaCTX-M-15 was integrated within an ISEcp1- blaCTX-M-15-wbuC- ∆Tn2 rare cassette.•blaCTX-M-15 was integrated in the vicinity of Enterobacter intact phage LAU1.•blaNDM-1 was integrated within a novel IncFII conjugative plasmid.
In the current study, the genotypic characteristics such as antimicrobial resistance and virulence genes, and plasmid replicons and phenotypic characteristics such as biofilm formation and ...antimicrobial resistance of 87 extended-spectrum beta-lactamase (ESBL)-producing E. coli (ESBL-Ec) isolated from 7 water bodies in northern Greece were investigated. Our data show a high prevalence (60.0 %) of ESBL-Ec in surface waters that exhibit high genetic diversity, suggesting multiple sources of their transmission into the aquatic environment. When evaluating the antimicrobial resistance of isolates, wide variation in their resistance profiles has been detected, with all isolates being multi-drug resistant (MDR). Regarding biofilm formation capacity and phylogenetic groups, the majority (54.0 %, 47/87) of ESBL-Ec were classified as no biofilm producers mainly assigned to phylogroup A (35.6 %; 31/87), followed by B2 (26.5 %; 23/87). PCR screening showed that a high proportion of the isolates tested positive for the blaCTX-M-1 group genes (69 %, 60/87), followed by blaTEM (55.2 %, 48/87), blaOXA (25.3 %, 22/87) and blaCTX-M-9 (17.2 %, 15/87). A subset of 28 ESBL-Ec strains was further investigated by applying whole genome sequencing (WGS), and among them, certain clinically significant sequence types were identified, such as ST131 and ST10. The corresponding in silico analysis predicted all these isolates as human pathogens, while a significant proportion of WGS-ESBL-Ec were assigned to extraintestinal pathogenic E. coli (ExPEC; 32.1 %), and urinary pathogenic E. coli (UPEC; 28.6 %) pathotypes. Comparative phylogenetic analysis, showed that the genomes of the ST131-O25:H4-H30 isolates are genetically linked to the human clinical strains. Here, we report for the first time the detection of a plasmid-mediated mobile colistin resistance gene in ESBL-Ec in Greece isolated from an environmental source. Overall, this study underlines the role of surface waters as a reservoir for antibiotic resistance genes and for presumptive pathogenic ESBL-Ec.
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•ESBL-Escherichia coli detected in 60.0 % of surface waters in Greece rivers.•All ESBL-Escherichia coli were characterized as multi-drug resistant.•blaCTX-M-1 group is predominant in the examined river waters.•ESBL-Escherichia coli from river waters are related to human clinical strains.
BACKGROUNDUrinary tract infection is one of the commonest infectious diseases worldwide. This study was carried out to determine the antimicrobial susceptibility pattern of bacteria causing urinary ...tract infection visiting Kathmandu University Hospital. METHODSA total of 3,500 urine samples were processed and antibiotic resistance pattern was determined following Clinical Laboratory Standard Institute guidelines. Patients' information was obtained after informed consent. RESULTSTotal number of samples with positive growth was 434 (12.40%). 331 (76.27%) of the isolates were Escherichia coli followed by Klebsiella pneumoniae, Enterococcus spp., Pseudomonas aeruginosa, Staphylococcus saprophyticus, Proteus mirabilis, Enterobacter species, Klebsiella oxytoca, Citrobacter freundii, Proteus vulgaris, Staphylococcus aureus and Acinetobacter species. Over all 224 (51.61%) were multidrug resistant strains. All strains were sensitive to colistin, vancomycin and linezolid. Over all ampicillin and cefazolin had least sensitivity. Multidrug resistant strains were detected more among elderly patients with complicated urinary tract infection and diabetes which was 25 (83.33%) compared to elderly patients with uncomplicated urinary tract infection and having no diabetes or any other comorbid illnesses which was only 11(22.22%) (p-value<0.05). 21 (70.00%) of the pregnant females had multidrug resistant isolates and only 18 (36.73%) of pediatric age group patients had multidrug resistant isolates (p-value<0.05) Conclusion: Drug-resistant bacteria were observed in urine samples. Effective treatment and prevention of urinary tract infection need detailed microbiological diagnosis and drug susceptibility testing.
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