Impact of pH on Activity of Trimethoprim, Fosfomycin, Amikacin, Colistin and Ertapenem in Human Urine
Impact of pH on Activity of Trimethoprim, Fosfomycin, Amikacin, Colistin and Ertapenem in Human Urine
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DOI：
10.1159/000342423
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发表时间：
2012-01-01
期刊：
影响因子：
3.1
通讯作者：
Zeitlinger, M.
中科院分区：
文献类型：
--
作者：
Burian, A.;Erdogan, Z.;Zeitlinger, M.
目的：尽管已报告氟喹诺酮类药物在较低pH值下的活性严重受损，但酸化是预防和治疗无并发症尿路感染（UTI）的广泛推荐做法。到目前为止，几乎没有证据表明pH值对尿液中其他抗微生物类的活性有影响。研究方法：在Mueller-Hinton肉汤和pH为5.0 - 8.0的合并人尿液中绘制金黄色葡萄球菌（ATCC 29213）、产酸克雷伯菌（ATCC 700324）、奇异变形杆菌（ATCC 14153）、大肠杆菌（ATCC 25922）和粪肠球菌（ATCC 29212）的细菌生长曲线。在等于MIC的浓度下连续测定甲氧苄啶、磷霉素、阿米卡星、粘菌素和厄他培南对5种菌株（适当时）的细菌杀灭作用。结果：大肠杆菌和大肠埃希菌的生长情况无明显差异。coli、S. aureus、P. mirabilis和K.在不同pH值条件下观察催产素对E.酸化至pH 5损害了所有研究的抗生素的抗微生物活性，即细菌生长和杀灭的净效应导致实验结束时菌落形成单位/ml增加。结论：目前的体外研究结果表明，在治疗尿路感染的尿液酸化应仔细考虑。虽然一种菌株的生长曲线支持UTI期间治疗性或预防性酸化的概念，但最常见的病原体E。大肠杆菌，不受低pH值的影响。独立的调查菌株或抗生素，pH值低于6导致抗菌活性降低。版权所有（C）2012 S. Karger AG，巴塞尔
Objective: Although major impairment of activity at lower pH values has been reported for fluoroquinolones, acidification is a widely recommended practice for the prophylaxis and treatment of uncomplicated urinary tract infections (UTIs). Until now, there is little evidence for the influence of pH on the activity on other antimicrobial classes in urine. Methods: Bacterial growth curves of Staphylococcus aureus (ATCC 29213), Klebsiella oxytoca (ATCC 700324), Proteus mirabilis (ATCC 14153), Escherichia coli (ATCC 25922) and Enterococcus faecalis (ATCC 29212) were performed in Mueller-Hinton broth and in pooled human urine with a pH of between 5.0 and 8.0. Bacterial killing of trimethoprim, fosfomycin, amikacin, colistin and ertapenem against the five strains (where appropriate) was determined consecutively at concentrations equal to the MIC. Results: While no difference in the bacterial growth of E. coli, S. aureus, P. mirabilis and K. oxytoca was observed at different pH values, bacterial growth of E. faecalis was significantly reduced at low pH. Acidification to pH 5 impaired the antimicrobial activity of all investigated antibiotics, i.e. the net effect of bacterial growth and killing resulted in increased colony-forming units/ml at the end of the experiment. Conclusion: The present in vitro findings indicate that acidification of urine during the treatment of UTIs should be carefully considered. While growth curves of one strain supports the concept of therapeutic or prophylactic acidification during UTIs, the most common pathogen, E. coli, was not affected by low pH. Independent of the investigated strain or antibiotic, pH values below 6 lead to a reduction of antimicrobial activity. Copyright (C) 2012 S. Karger AG, Basel