Comparative in vitro activity of vancomycin and levofloxacin in combination with rifampin against planktonic versus sessile cells of Staphylococcus epidermidis
Abstract
STUDY OBJECTIVE: To evaluate the activity of vancomycin and levofloxacin alone and combined with rifampin against planktonic and sessile cells.
INTERVENTION: Minimum inhibitory concentrations (MICs) and minimum bactericidal concentrations (MBCs) of the three drugs were determined against a clinical isolate of methicillin-resistant Staphylococcus epidermidis (MRSE 23) and a reference strain of MRSE (ATCC 35984).
MEASUREMENTS AND MAIN RESULTS: The MICs/MBCs of vancomycin, levofloxacin, and rifampin against MRSE 23 were 0.78/0.78 microg/ml, 0.19/0.19 microg/ml or below, and 0.19/0.19 microg/ml or below, and against ATCC 35984 were 0.78/1.56 microg/ml, 0.19/0.19 microg/ml or below, and 0.19/0.19 microg/ml or below, respectively. A 99.9% killing activity was achieved with vancomycin, levofloxacin, and vancomycin-levofloxacin against planktonic cells of MRSE 23 (18.9, 21.3, and 17.5 hrs, respectively) and only with levofloxacin against ATCC 35984 (21.5 hrs). No regimen achieved 99.9% killing activity against sessile cells.
CONCLUSION: Adding rifampin was antagonistic against planktonic cells and had an additive effect against sessile cells. Activity typically reported using nutrient-rich, planktonic cells may not be applicable to sessile cells under environmental and growth restrictions.
Read the paper
Related studies
- Ferulic acid regulates the AKT/GSK-3β/CRMP-2 signaling pathway in a middle cerebral artery occlusion animal model
- Novel Pharmacokinetic/Pharmacodynamic Parameters Quantify the Exposure–Effect Relationship of Levofloxacin against Fluoroquinolone-Resistant Escherichia coli
- Photochemical behavior of levofloxacin
- Correlation Between Dissolution Profiles of Salt-Form Drugs in Biorelevant Bicarbonate Buffer and Oral Drug Absorption: Importance of Dose/ Fluid Volume Ratio
- Evaluation of the synergistic potential and mechanisms of action for de novo designed cationic antimicrobial peptides
- Synthesis of [11C]levofloxacin
Go deeper in Evidence Hub
Evidence Hub adds a study data sheet (design, sample size, evidence level, key numbers), an AI summary and a chat grounded in the paper's text.