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Published on: June 5, 2012
In-vitro susceptibility of oral streptococci to pristinamycin
Abstract:
The inhibitory activity of pristinamycin against oral streptococci was compared with that of amoxycillin, erythromycin and vancomycin. Minimum inhibitory concentrations (MICs) of pristinamycin ranged from 0.03-1 mg/l (mode 0.25 mg/l), similar to those for amoxycillin. Erythromycin had a mode MIC of 0.06 mg/l and vancomycin, the least active, 1 mg/l. However, in killing curve experiments to compare the bactericidal activities of pristinamycin and erythromycin against several strains of oral streptococci, pristinamycin was substantially more active, consistently producing a rapid decrease in viable count during the first few hours of incubation. Pristinamycin may prove to be of value for the prophylaxis of post-dental extraction bacteraemia.
Insights
Pristinamycin exhibits potent inhibitory and bactericidal activity against oral streptococci, comparable to amoxycillin and superior to erythromycin. This antibiotic shows promise for preventing bacteremia after dental procedures.
Area of Science:
- Microbiology
- Pharmacology
- Infectious Diseases
Background:
- Oral streptococci are common inhabitants of the oral cavity and can cause infections.
- Antibiotic resistance is a growing concern in managing bacterial infections.
- Pristinamycin is a streptogramin antibiotic with known activity against Gram-positive bacteria.
Purpose of the Study:
- To compare the in vitro inhibitory and bactericidal activities of pristinamycin against oral streptococci with other common antibiotics.
- To evaluate the potential of pristinamycin for prophylaxis of post-dental extraction bacteremia.
Main Methods:
- Minimum Inhibitory Concentration (MIC) assays were performed to determine the inhibitory activity of pristinamycin, amoxycillin, erythromycin, and vancomycin.
- Killing curve experiments were conducted to assess the bactericidal activity of pristinamycin and erythromycin against oral streptococci strains.
Main Results:
- Pristinamycin demonstrated minimum inhibitory concentrations (MICs) ranging from 0.03-1 mg/l (mode 0.25 mg/l), similar to amoxycillin.
- Erythromycin had a mode MIC of 0.06 mg/l, while vancomycin showed the least activity with a mode MIC of 1 mg/l.
- Pristinamycin exhibited significantly greater bactericidal activity than erythromycin in killing curve experiments, rapidly reducing viable bacterial counts.
Conclusions:
- Pristinamycin possesses potent inhibitory and bactericidal properties against oral streptococci.
- Its efficacy suggests potential utility in preventing bacteremia following dental extractions.
- Further clinical investigations are warranted to confirm pristinamycin's role in prophylaxis.
