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High Throughput, Real-time, Dual-readout Testing of Intracellular Antimicrobial Activity and Eukaryotic Cell Cytotoxicity
Published on: November 16, 2016
Comparative in vitro activities of selected antimicrobial agents against Edwardsiella tarda
Abstract:
MICs of 14 antimicrobial agents for 29 strains of Edwardsiella tarda were determined by an agar dilution method. Of the agents tested, ciprofloxacin, enoxacin, and norfloxacin were the most active on a weight basis. All strains were also susceptible to clinically achievable concentrations of ampicillin, chloramphenicol, tetracycline, trimethoprim, sulfamethoxazole, trimethoprim plus sulfamethoxazole, cefotaxime, and gentamicin. Ninety percent of the strains demonstrated high-level resistance to polymyxin B and colistin.
Insights
This study determined antimicrobial susceptibility for Edwardsiella tarda. Ciprofloxacin, enoxacin, and norfloxacin showed high activity, while most strains were resistant to polymyxin B and colistin.
Area of Science:
- Microbiology
- Antimicrobial Resistance
Background:
- Edwardsiella tarda is an opportunistic pathogen.
- Understanding its antimicrobial susceptibility is crucial for effective treatment.
Purpose of the Study:
- To determine the minimum inhibitory concentrations (MICs) of various antimicrobial agents against Edwardsiella tarda strains.
- To identify effective and ineffective antimicrobial agents for treating Edwardsiella tarda infections.
Main Methods:
- Agar dilution method was used to test 14 antimicrobial agents.
- 29 strains of Edwardsiella tarda were analyzed.
Main Results:
- Ciprofloxacin, enoxacin, and norfloxacin were the most potent agents on a weight basis.
- All strains were susceptible to ampicillin, chloramphenicol, tetracycline, trimethoprim, sulfamethoxazole, trimethoprim/sulfamethoxazole, cefotaxime, and gentamicin at clinically achievable concentrations.
- High-level resistance (90% of strains) was observed against polymyxin B and colistin.
Conclusions:
- Fluoroquinolones (ciprofloxacin, enoxacin, norfloxacin) are effective against Edwardsiella tarda.
- Several other antibiotics, including ampicillin, chloramphenicol, tetracycline, and gentamicin, remain viable treatment options.
- Polymyxin B and colistin are not recommended for treating Edwardsiella tarda infections due to widespread resistance.
