background: in order to select a better antibiotic choice for treatment of pseudomonas aeruginosa infections, this study was conducted to determine the frequency of resistance to some antipseudomonal β-lactams in p. aeruginosa isolates from patients in tehran, iran. in addition, the relation between presence of genes known to be responsible for resistance to β-lactams (ampc, mexc1,2,and mexc3,4...

Introduction: This study is aimed to compare phenotypic test methods and determine antibiotic susceptibility pattern of AmpC beta-lactamase producing uropathogenic Escherichia coli and Klebsiella pneumoniae in clinical isolates. Method: E. coli and K. pneumoniae were identified by standard microbiological procedures. Screening of AmpC beta-lactamase production was done by using cefoxitin disc (...

conclusions a high prevalence of multiple β-lactamase production was observed among the ampc producers (60%), of which the majority co-produced ampc and mbl. the current study results showed correlation between β-lactamase production and the presence of antibiotic resistance genes in the isolates. results all isolates were multidrug resistant. ampc, esbl and mbl production were observed in 35 (...

Current study was conducted to determine prevalence and antimicrobial susceptibility patterns, ESBL, AmpC and carbapenemase- producers among clinical isolates of Enterobacteriaceae. Three hundred and seven non-duplicative clinical isolates were collected from hospitalized patients in five medical centers in Azerbaijan, Iran. Initial screening for β-lactamase production was performed using disc ...

Antimicrobial resistance of Escherichia coli to modern beta-lactam antibiotics due to the production of extended-spectrum beta-lactamases (ESBL) and/or plasmid-mediated AmpC beta-lactamases (AmpC) represents an emerging and increasing resistance problem that dramatically limits therapeutic options in both human and veterinary medicine. The presence of ESBL/AmpC genes in commensal E. coli from f...

Two-hundred consecutive, single patient isolates of Enterobacter spp., Serratia spp., Citrobacter spp., and Pseudomonas aeruginosa were evaluated for AmpC production using a variety of inducer-substrate antibiotic combinations in a disk approximation format. The combinations examined included cefoxitin-piperacillin, imipenem-cefotaxime, imipenem-ceftazidime, imipenem-piperacillin-tazobactam, an...

Results: Overgrowth occurred on agar with low MIC multiples of ceftaroline+avibactam, but frequencies for single-step mutants were ,10. Most mutants were unstable, with only three remaining resistant on subculture. For one, from an CTX-M-15-positive Escherichia coli, the ceftaroline+avibactam MIC was raised, but the organism had reduced resistance to ceftaroline and lost resistance to other oxy...

A major reason for resistance of Enterobacteriaceae to beta-lactam antibiotics is production of ESBLs and AmpC beta-lactamases. As their more detailed description in poultry is unavailable in the Czech Republic, the presented study aimed at assessing their occurrence and molecular characteristics. A total of 154 composite samples from broilers and 150 cloacal swabs from turkeys were examined. P...

DHA-1 is an inducible plasmid-mediated AmpC b-lactamase whose emergence raises concerns because the mortality of patients infected with organisms that produce DHA-1 has been shown to be higher than that of patients infected with organisms that produce CMY-1. In conclusion, we have demonstrated that plasmid-mediated AmpC b-lactamases have emerged in Switzerland. The prevalence of 0.16% is still ...

conclusions biofilm formation (both strong and weak) strongly correlated with psla gene carriage. biofilm formation also correlated with mbl and ampc β-lactamase production. more importantly, multiple-β-lactamase phenotype was associated with formation of strong biofilms. results biofilm formation was observed in 43.5% of the isolates, of which 66.7% produced strong and 33.3% formed weak biofil...