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A Protocol to Characterize the Morphological Changes of Clostridium difficile in Response to Antibiotic Treatment
Published on: May 25, 2017
RP 59500 postantibiotic effect defined by bacterial ultrastructure
V Lorian1, L Amaral, F Fernandes
1Department of Epidemiology and Infection Control, Bronx Lebanon Hospital Center, New York 10457, USA.
Drugs Under Experimental and Clinical Research
|January 1, 1995
Summary
This study investigated the postantibiotic effect (PAE) of streptogramin RP 59500 on Staphylococcus aureus. RP 59500 demonstrated a significant PAE, lasting up to eight hours.
Area of Science:
- Microbiology
- Pharmacology
- Bacterial Pathogenesis
Background:
- Staphylococcus aureus is a significant human pathogen.
- Understanding postantibiotic effects (PAE) is crucial for optimizing antimicrobial therapy.
- Streptogramins are a class of antibiotics with potential against resistant bacteria.
Purpose of the Study:
- To determine the postantibiotic effect (PAE) of the streptogramin RP 59500 against Staphylococcus aureus.
- To evaluate the duration of PAE using different methodologies.
Main Methods:
- Exposure of Staphylococcus aureus to RP 59500 at 0.75 times the minimum inhibitory concentration (MIC) for six hours.
- Washing and resuspension in fresh medium for a ten-hour incubation period.
- Determination of PAE through growth kinetics (colony-forming units) and bacterial ultrastructure (cell diameter).
Main Results:
- A significant postantibiotic effect was observed.
- PAE duration varied depending on the measurement method: eight hours by cell diameter changes and three hours by colony-forming unit counts.
- Bacterial ultrastructure changes indicated a prolonged effect.
Conclusions:
- RP 59500 exhibits a notable postantibiotic effect on Staphylococcus aureus.
- The method used for PAE determination influences the measured duration.
- Further research into streptogramin PAE may inform treatment strategies against S. aureus infections.
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