Zhanel G G, Karlowsky J A, Davidson R J, Hoban D J
Department of Medical Microbiology, University of Manitoba Health Sciences Centre, Winnipeg, Canada.
Chemotherapy. 1991;37(3):218-23. doi: 10.1159/000238857.
The purpose of this investigation was to study the effects of human urine on the minimum inhibitory concentration (MIC) and the postantibiotic effect (PAE) of ciprofloxacin against Escherichia coli. MICs and the PAE were performed in Mueller-Hinton broth (MHB; pH 7.3 and 5.5) and in human urine (pH 5.5 and 7.3). In urine, pH 5.5, MICs increased 64-fold (from 0.016 to 1.024 micrograms/ml) and the PAE was abolished (from 101.6 to 3.7 min), when compared to MHB, pH 7.3. An acidic pH demonstrated the greatest effect on reduced susceptibility and PAE. Using ciprofloxacin concentrations adjusted for a higher MIC obtained in pH-adjusted urine and MHB, PAE values were similar for urine and MHB (approximately 280 min at 40 x MIC). This study demonstrated that the MIC and PAE of ciprofloxacin against E. coli are influenced by human urine and in particular its pH.
本研究的目的是探讨人尿液对环丙沙星对大肠杆菌的最低抑菌浓度（MIC）和抗生素后效应（PAE）的影响。在 Mueller-Hinton 肉汤（MHB；pH 7.3 和 5.5）和人尿液（pH 5.5 和 7.3）中测定 MIC 和 PAE。在尿液中，pH 5.5 时，与 pH 7.3 的 MHB 相比，MIC 增加了 64 倍（从 0.016 微克/毫升增至 1.024 微克/毫升），且 PAE 消失（从 101.6 分钟降至 3.7 分钟）。酸性 pH 对敏感性降低和 PAE 的影响最大。使用根据在 pH 调整的尿液和 MHB 中获得的较高 MIC 进行调整的环丙沙星浓度时，尿液和 MHB 的 PAE 值相似（在 40 倍 MIC 时约为 280 分钟）。本研究表明，环丙沙星对大肠杆菌的 MIC 和 PAE 受人尿液尤其是其 pH 的影响。
