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Updated: Jun 5, 2026
08:06
The Use of a β-lactamase-based Conductimetric Biosensor Assay to Detect Biomolecular Interactions
Published on: February 1, 2018
[Research regarding extended-spectrum beta-lactamases produced by enterobacteria strains]
Brînduşa Copăcianu1, Cristina Tuchiluş, Antonia Poiata
1Doctorand al Universităţii de Medicină şi Farmacie Gr. T. Popa Iaşi.
Summary
Extended spectrum beta-lactamase (ESBL) producing Escherichia coli and Klebsiella pneumoniae show high resistance to common antibiotics. Carbapenems, including ertapenem, imipenem, and meropenem, remain highly effective against these resistant strains.
Area of Science:
- Medical Microbiology
- Infectious Diseases
- Antimicrobial Resistance
Background:
- Extended spectrum beta-lactamase (ESBL) production is a significant mechanism of antimicrobial resistance in Gram-negative bacteria.
- Escherichia coli and Klebsiella pneumoniae are common causes of hospital-acquired and community-acquired infections.
Purpose of the Study:
- To determine the susceptibility patterns of ESBL-producing Escherichia coli and Klebsiella pneumoniae.
- To evaluate antimicrobial resistance in clinical isolates from hospital and community settings.
Main Methods:
- Phenotypic confirmation of ESBL production using double disk test and replacement disk method.
- Minimum inhibitory concentrations (MICs) determined by agar dilution for various antimicrobial agents.
- Resistance rates assessed using Clinical Laboratory Standard Institute (CLSI) breakpoints.
Main Results:
- Very high resistance rates observed for ceftazidime, cefotaxime, ceftriaxone, and aztreonam in both E. coli and K. pneumoniae.
- High MIC90 values (> 256 mg/L) for tested cephalosporins and aztreonam.
- All isolates demonstrated susceptibility to carbapenems: ertapenem, imipenem, and meropenem.
Conclusions:
- High rates of resistance to third-generation cephalosporins and aztreonam were confirmed.
- Carbapenems exhibit potent activity against ESBL-producing E. coli and K. pneumoniae, representing a crucial treatment option.
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