Consistent rates of kill of Staphylococcus aureus by gentamicin over a 6-fold clinical concentration range in an in vitro pharmacodynamic model (IVPDM).
Consistent rates of kill of Staphylococcus aureus by gentamicin over a 6-fold clinical concentration range in an in vitro pharmacodynamic model (IVPDM).
复制标题
在体外药效模型 (IVPDM) 中，庆大霉素在 6 倍临床浓度范围内对金黄色葡萄球菌的杀灭率保持一致。
DOI：
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发表时间：
2006
影响因子：
5.2
通讯作者：
J. Rotschafer
中科院分区：
文献类型：
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作者：
Jeremy A. Schafer;L. B. Hovde;J. Rotschafer
目标
比较6倍庆大霉素浓度范围对金黄色葡萄球菌的细菌杀灭效果。
方法
使用接种10（6）cfu/mL S的体外药效学模型（IVPDM）进行了6次24 h重复实验。金黄色葡萄球菌（ATCC 29213），并使其经受0、5、10、15和20 mg/L的所需初始庆大霉素浓度。庆大霉素的半衰期为2小时。在0.5、1、1.5、2、3、4、6、9和24 h时取样，以定量cfu/mL和庆大霉素浓度。对这些样本进行连续盐水稀释，以防止抗生素残留并产生可计数的菌落。对S.金黄色。为每个实验生成一式两份24 h杀灭曲线，并评估杀灭曲线斜率和至3 log杀灭时间之间的统计学差异（双因素ANOVA）。
结果
分析至2 h时间点的杀伤曲线斜率，发现不同浓度之间无统计学差异（P > 0.05）。至3 log杀灭的时间在浓度之间无显著差异。暴露后庆大霉素MIC值在暴露前MIC值（0.25 mg/L）的一管稀释范围内。
结论
这些数据表明临床庆大霉素浓度可杀死S。金黄色葡萄球菌具有等效的有效性，使用更高剂量的氨基糖苷类可能不会提高细菌杀灭率。
OBJECTIVES
To compare the effect of a 6-fold range in gentamicin concentration on the bacterial killing of Staphylococcus aureus.
METHODS
Six 24 h duplicate experiments were performed using an in vitro pharmacodynamic model (IVPDM) which was inoculated with 10(6) cfu/mL S. aureus (ATCC 29213) and subjected to desired initial gentamicin concentrations of 0, 5, 10, 15 and 20 mg/L. A 2 h half-life was emulated for gentamicin. Samples were drawn at 0.5, 1, 1.5, 2, 3, 4, 6, 9 and 24 h to quantify cfu/mL and gentamicin concentration. These samples were subjected to serial saline dilution to prevent antibiotic carryover and to produce a countable number of colonies. Pre- and post-gentamicin MIC values were performed for S. aureus. Duplicate 24 h kill curves were generated for each experiment and assessed for statistical difference (two-way ANOVA) between the slopes of the kill curves and time to 3 log kill.
RESULTS
Kill curve slopes were analysed out to the 2 h time point and no statistical difference was found between the different concentrations (P > 0.05). Time to 3 log kill was not significantly different between the concentrations. Post-exposure gentamicin MIC values were within one tube dilution of the pre-exposure MIC value (0.25 mg/L).
CONCLUSIONS
These data demonstrate that clinical gentamicin concentrations kill S. aureus with equivalent effectiveness and that the use of higher doses of aminoglycosides would probably not improve bacterial kill rates.