Incidence of temonera, sulphuhydryl variables and cefotaximase genes associated with beta-lactamase producing escherichia coli in clinical isolates

A mouse model of bacteremia was used to compare the efficacies of 1.5- and 3.0-g intravenous doses of ampicillin-sulbactam. Seven strains of Escherichia coli producing various levels of TEM-1 beta-lactamase were used as the challenge isolates. These strains included six clinical isolates (MICs from 2/1 micrograms/ml [with 2 and 1 microgram/ml being the respective concentrations of ampicillin and sulbactam] to 32/16 micrograms/ml) with similar degrees of virulence in mice and a laboratory genetic transformant (E. coli AFE) which hyperproduces TEM-1 (MIC = 128/64 micrograms/ml). Human pharmacokinetics were simulated by injecting mice subcutaneously twice (1 h apart) with ampicillin-sulbactam at concentrations of 40 mg/kg of body weight (1.5 g) and 80 mg/kg (3.0 g). Against two clinical isolates for which ampicillin-sulbactam MICs were < or = 8/4 micrograms/ml, no difference was observed in either the rate or level of killing between the two doses, and both doses were 100% protective against lethal infection. Against the four clinical isolates for which ampicillin-sulbactam MICs were between 16/8 and 32/16 micrograms/ml, a slight delay in killing was noted with three of the strains. This delay was followed by a rapid 2- to 3-log drop in the level of bacteremia, and both doses of ampicillin-sulbactam were 100% protective against lethal septicemia. With strain AFE, no killing was observed with the 40-mg/kg dose compared with a 2-log killing with the 80-mg/kg dose. This difference in killing correlated with a decreased protective efficacy of the 40-mg/kg dose. These data suggest that the 1.5-g preparation of ampicillin-sulbactam is as effective as the 3.0-g dose in the treatment of experimentally induced E. coli bacteremia, as long as ampicillin-sulbactam MICs are 32/16 micrograms/ml or less.

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High prevalence of blaCMY AmpC beta-lactamase in ESBL co-producing Escherichia coli and Klebsiella spp. clinical isolates in the northeast of Iran

Journal of Global Antimicrobial Resistance ◽

10.1016/j.jgar.2020.03.011 ◽

2020 ◽

Vol 22 ◽

pp. 477-482 ◽

Cited By ~ 1

Author(s):

Kobra Salimiyan Rizi ◽

Arman Mosavat ◽

Masoud Youssefi ◽

Saeid Amel Jamehdar ◽

Kiarash Ghazvini ◽

...

Keyword(s):

Escherichia Coli ◽

Clinical Isolates ◽

Beta Lactamase ◽

High Prevalence ◽

Klebsiella Spp

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Extended-spectrum beta-lactamases producing Escherichia coli and Klebsiella pneumoniaei: A Multi-centric Study Across Karnataka

Journal of Laboratory Physicians ◽

10.4103/0974-2727.129083 ◽

2014 ◽

Vol 6 (01) ◽

pp. 007-013 ◽

Cited By ~ 13

Author(s):

Sridhar PN Rao ◽

Prasad Subba Rama ◽

Vishwanath Gurushanthappa ◽

Radhakrishna Manipura ◽

Krishna Srinivasan

Keyword(s):

Escherichia Coli ◽

Clinical Isolates ◽

Beta Lactamase ◽

Beta Lactam ◽

Esbl Production ◽

Beta Lactamases ◽

E Coli ◽

Karnataka State ◽

Extended Spectrum Beta Lactamases ◽

Esbl Producers

ABSTRACT Background: There are sporadic reports on detection of extended-spectrum beta-lactamases (ESBL) producers from Karnataka; hence, this is a first multicentric study across Karnataka state to determine the prevalence of ESBL production among clinical isolates of Escherichia coli and Klebsiella pneumoniaei. Aims and objectives: To determine the prevalence of ESBL producing clinical isolates of E. coli and K. pneumoniae from five geographically distributed centers across Karnataka, to study the susceptibility of ESBL producing isolates to other beta-lactam and beta-lactam-beta-lactamase inhibitors and to demonstrate transferability of plasmids coding for ESBL phenotype. Materials and Methods: Two hundred isolates of E. coli and K. pneumoniae each were collected from each of the five centers (Bellary, Dharwad, Davangere, Kolar and Mangalore). They were screened for resistance to screening agents (ceftazidime, cefotaxime, ceftriaxone, aztreonam) and positive isolates were confirmed for ESBL production by test described by Clinical and Laboratory Standards Institute . Co-production of ESBL and AmpC beta-lactamase was identified by using amino-phenylboronic acid disk method. Susceptibility of ESBL producers to beta-lactam antibiotics and beta-lactamase inhibitors was performed. Transferability of plasmids was performed by conjugation experiment. Results: Overall prevalence of ESBL production among E. coli and K. pneumoniae across five centers of the state was 57.5%. ESBL production was found to be 61.4% among E. coli and 46.2% among K. pneumoniae. ESBL production was significantly more among E. coli than K. pneumoniae. Significant variations in distribution of ESBL across the state was observed among E. coli isolates, but not among K. pneumoniae isolates. All ESBL producers demonstrated minimum inhibitory concentration levels ≥2 μg/ml towards cefotaxime, ceftazidime and ceftriaxone. Conclusion: Overall prevalence of ESBL production among clinical isolates of E. coli and K. pneumoniae across Karnataka state was high. The prevalence of ESBL production was significantly higher with E. coli than K. pneumoniae isolates. Higher rates of resistance to ceftriaxone and cefotaxime than to ceftazidime suggests the possibility of presence of CTX-M type ESBLs. Of all the beta-lactam/beta-lactamase inhibitor combinations tested, cefepime-tazobactam demonstrated highest in-vitro activity against ESBL producers. There was no statistical difference in the transferability of plasmids among E. coli and K. pneumoniae.

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Activityin vitro of twelve antibiotics against clinical isolates of extended-spectrum beta-lactamase producing Escherichia coli

Journal of Basic Microbiology ◽

10.1002/jobm.200710318 ◽

2007 ◽

Vol 47 (5) ◽

pp. 413-416 ◽

Cited By ~ 7

Author(s):

Antonio Sorlózano ◽

José Gutiérrez ◽

José María Romero ◽

Juan de Dios Luna ◽

Miguel Damas ◽

...

Keyword(s):

Escherichia Coli ◽

Clinical Isolates ◽

Beta Lactamase ◽

Extended Spectrum Beta Lactamase ◽

Extended Spectrum

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Evaluation of phenotypic tests for the detection of AmpC beta-lactamase in clinical isolates of Escherichia coli

Indian Journal of Pathology and Microbiology ◽

10.4103/0377-4929.118686 ◽

2013 ◽

Vol 56 (2) ◽

pp. 135 ◽

Cited By ~ 6

Author(s):

Anita Pandey ◽

Ashutosh Rawat ◽

Seemant Handa ◽

Bhaskar Thakuria ◽

Deepika Handa ◽

...

Keyword(s):

Escherichia Coli ◽

Clinical Isolates ◽

Beta Lactamase ◽

Phenotypic Tests

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1216. Presence of the Narrow-Spectrum OXA-1 Beta-lactamase Enzyme Is Associated with Elevated Piperacillin-Tazobactam MIC Values Among ESBL-producing Escherichia coli Clinical Isolates (CANWARD, 2007-2018)

Open Forum Infectious Diseases ◽

10.1093/ofid/ofab466.1408 ◽

2021 ◽

Vol 8 (Supplement_1) ◽

pp. S697-S697

Author(s):

Andrew Walkty ◽

James Karlowsky ◽

Philippe Lagace-Wiens ◽

Alyssa Golden ◽

Melanie Baxter ◽

...

Keyword(s):

Escherichia Coli ◽

Clinical Isolates ◽

Beta Lactamase ◽

Gene Detection ◽

Research Support ◽

Extended Spectrum Beta Lactamase ◽

E Coli ◽

Narrow Spectrum ◽

The Family ◽

Lactamase Gene

Abstract Background The clinical outcome of patients with bacteremia due to an extended-spectrum beta-lactamase (ESBL)-producing member of the family Enterobacteriaceae who are treated with piperacillin-tazobactam appears to depend, at least in part, on the piperacillin-tazobactam MIC. The purpose of this study was to determine whether there is any association between the MIC of piperacillin-tazobactam and presence of the narrow spectrum OXA-1 beta-lactamase enzyme among ESBL-producing Escherichia coli. Methods E. coli clinical isolates were obtained from patients evaluated at hospitals across Canada (January 2007 to December 2018) as part of an ongoing national surveillance study (CANWARD). ESBL production was confirmed using the Clinical and Laboratory Standards Institute phenotypic method. Susceptibility testing was carried out using custom broth microdilution panels, and all isolates underwent whole genome sequencing for beta-lactamase gene detection. Results In total, 671 ESBL-producing E. coli were identified as part of the CANWARD study. The majority of isolates (92.0%; 617/671) harbored a CTX-M ESBL enzyme. CTX-M-15 (62.3%; 418/671), CTX-M-27 (13.9%; 93/671), and CTX-M-14 (13.4%; 90/671) were the most common variants identified. The narrow spectrum OXA-1 beta-lactamase enzyme was present in 42.6% (286/671) of isolates. OXA-1 was detected in 66.3% (277/418) of isolates with a CTX-M-15 ESBL enzyme versus only 3.6% (9/253) of isolates with other ESBL enzyme types. The piperacillin-tazobactam MIC50 and MIC90 values were 8 µg/mL and 32 µg/mL for isolates that possessed the OXA-1 enzyme versus 2 μg/mL and 8 µg/mL for those that did not. The percentage of ESBL-producing E. coli isolates that were inhibited by a piperacillin-tazobactam MIC of ≤8 μg/mL was 68.5% for isolates that were OXA-1 positive and 93.8% for isolates that were OXA-1 negative. Conclusion The MIC50 and MIC90 values of piperacillin-tazobactam among ESBL-producing E. coli were higher for the subset of isolates that harbored a narrow spectrum OXA-1 beta-lactamase enzyme relative to the subset that did not. This association was primarily observed among ESBL-producers with the CTX-M-15 enzyme variant. OXA-1 was infrequently detected among isolates with other ESBL enzyme types. Disclosures George Zhanel, PhD, AVIR (Grant/Research Support)Iterum (Grant/Research Support)Merck (Grant/Research Support)Pfizer (Grant/Research Support)Sandoz (Grant/Research Support)Sunovion (Grant/Research Support)Venatorx (Grant/Research Support)Verity (Grant/Research Support)

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