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Postantibiotic effect of ceftaroline against gram-positive organisms
1Department of Pathology, Hershey Medical Center, Hershey, PA 17033, USA.
Antimicrobial Agents and Chemotherapy
|September 23, 2009
Summary
Ceftaroline demonstrated significant postantibiotic effects (PAEs) against gram-positive bacteria. Sub-inhibitory concentrations of ceftaroline extended these effects, suggesting enhanced antimicrobial activity.
Area of Science:
- Microbiology
- Pharmacology
- Infectious Diseases
Background:
- Ceftaroline is a novel cephalosporin with broad-spectrum activity against Gram-positive pathogens.
- Understanding the postantibiotic effects (PAEs) and sub-MIC effects (SMEs) is crucial for optimizing antibiotic dosing and efficacy.
Purpose of the Study:
- To determine the postantibiotic effects (PAEs), postantibiotic sub-MIC effects (PA-SMEs), and sub-MIC effects (SMEs) of ceftaroline.
- To evaluate the impact of sub-inhibitory concentrations on ceftaroline's antimicrobial activity against Gram-positive organisms.
Main Methods:
- Ceftaroline's PAEs, PA-SMEs, and SMEs were assessed against 15 Gram-positive organisms.
- Organisms included strains of Streptococcus pneumoniae, Staphylococcus spp., and Enterococcus spp.
Main Results:
- Ceftaroline exhibited PAEs ranging from 0.8 to 1.8 h for pneumococci, 0.7 to 2.2 h for staphylococci, and 0.2 to 1.1 h for enterococci.
- PA-SMEs were notably longer than PAEs, with values ranging from 2.5 to 6.7 h, 2.9 to >0.0 h, and 7.9 to >10.3 h, respectively.
- Sub-MIC levels of ceftaroline significantly prolonged the observed postantibiotic effects.
Conclusions:
- Sub-inhibitory concentrations of ceftaroline extend its postantibiotic effect against Gram-positive cocci.
- These findings suggest that ceftaroline maintains significant antimicrobial activity even at concentrations below the minimum inhibitory concentration (MIC).
- Further research may elucidate the clinical implications of these extended effects for treatment strategies.
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