Samar A Ahmed, Vy T Luu, Teresa C Oyono Nsuga, Steven E Burgos, Eugene Kreys, Jered Arquiette, Justin R Lenhard
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引用次数: 0
Abstract
Background/Objectives: The optimal therapy for polymicrobial wound infections is poorly defined. We sought to characterize the ability of linezolid to combat mixed cultures of Staphylococcus aureus and Pseudomonas aeruginosa. Methods: The antistaphylococcal activity of linezolid was assessed in 24-h time-killing experiments that used S. aureus and P. aeruginosa isolated from polymicrobial wound infections. Clindamycin was also evaluated as a comparator. A Hill-type mathematical model was used to assess the maximum killing of S. aureus (Emax). The ability of linezolid to potentiate the activity of host defense peptides against P. aeruginosa was evaluated using LL-37. Results: In the presence of P. aeruginosa, the Emax of linezolid decreased in 5/9 co-culture experiments and increased in 4/9 co-culture experiments in comparison to linezolid against S. aureus alone. The potency of linezolid was not significantly impacted by the presence of P. aeruginosa. In comparison, the maximal S. aureus killing achieved by clindamycin decreased in eight out of nine experiments, and somewhat paradoxically, the potency increased in nine out of nine experiments. In the host defense peptide assay, the supratherapeutic linezolid concentration of 64 mg/L did not significantly enhance the killing of the LL-37 peptides (p ≥ 0.121), but the concentration of linezolid was significantly associated with the killing of one of three P. aeruginosa isolates (p = 0.005). Conclusions: P. aeruginosa had a minimal impact on the antistaphylococcal activity of linezolid in comparison to clindamycin. Linezolid did not exert a consistent ability to enhance the antipseudomonal activity of host defense peptides. These data may help inform antimicrobial selection during polymicrobial wound infections.
Antibiotics-BaselPharmacology, Toxicology and Pharmaceutics-General Pharmacology, Toxicology and Pharmaceutics
CiteScore
7.30
自引率
14.60%
发文量
1547
审稿时长
11 weeks
期刊介绍:
Antibiotics (ISSN 2079-6382) is an open access, peer reviewed journal on all aspects of antibiotics. Antibiotics is a multi-disciplinary journal encompassing the general fields of biochemistry, chemistry, genetics, microbiology and pharmacology. Our aim is to encourage scientists to publish their experimental and theoretical results in as much detail as possible. Therefore, there is no restriction on the length of papers.