Related Experiment Videos
Post-antibiotic effect and killing activity of ciprofloxacin against Staphylococcus aureus
Abstract:
The effect of ciprofloxacin on eight strains of Staphylococcus aureus were examined. A post-antibiotic effect was observed in all strains, varying between 1.65 and 2.75 hours, with concentration of ciprofloxacin at 5 times the Minimum Inhibitory Concentration (MIC) exposed for 1 hour. Killing-kinetic studies at 5 times the MIC showed a decrease in the numbers of organisms by approximately 2.1 log10 after 6 hours, independent of the growth phase. A significantly increased susceptibility of S. aureus to the bactericidal activity of ciprofloxacin during recovery from the PAE-phase was demonstrated.
Insights
Ciprofloxacin demonstrated a post-antibiotic effect (PAE) on Staphylococcus aureus strains, lasting up to 2.75 hours. Increased susceptibility to ciprofloxacin
Area of Science:
- Microbiology
- Pharmacology
- Infectious Diseases
Background:
- Staphylococcus aureus is a significant human pathogen.
- Understanding antibiotic effects on S. aureus is crucial for treatment strategies.
Purpose of the Study:
- To investigate the post-antibiotic effect (PAE) and bactericidal activity of ciprofloxacin against Staphylococcus aureus.
- To determine the impact of ciprofloxacin exposure on bacterial susceptibility.
Main Methods:
- Examined the effect of ciprofloxacin on eight S. aureus strains.
- Determined PAE by exposing bacteria to 5x MIC for 1 hour.
- Conducted killing-kinetic studies at 5x MIC.
- Assessed bacterial susceptibility during recovery from PAE.
Main Results:
- A PAE was observed in all strains, ranging from 1.65 to 2.75 hours.
- Killing-kinetic studies showed a ~2.1 log10 decrease in bacterial numbers after 6 hours.
- S. aureus showed significantly increased susceptibility to ciprofloxacin during PAE recovery.
Conclusions:
- Ciprofloxacin exhibits a notable PAE and bactericidal effect against S. aureus.
- Bacterial susceptibility to ciprofloxacin is enhanced following the PAE phase.
- These findings have implications for optimizing ciprofloxacin dosing regimens.