SUSCEPTIBILITY OF E COLI TO AMOXICILLIN/CLAVULANATE AND AMPICILLIN/SULBACTAM

该项目的主要重点一直是研究体外培养的 氨苄西林耐药大肠埃希菌对抗生素敏感性的研究 阿莫西林/克拉维酸和氨苄西林/舒巴坦。这两个 抗生素-β-内酰胺酶抑制剂组合已被声明为 在临床疗效上具有可比性，因此应该 它们的体外药敏结果具有可比性。缺乏 两者常规药敏试验结果的相关性 临床分离的耐氨苄西林E。 来自美国国立卫生研究院患者的大肠杆菌。这个 结果的重现性通过重复 对分离株进行了药敏试验程序，其有效性是 通过执行敏感度测试进行进一步调查 方法：研究方法。182株氨苄西林耐药菌株药敏结果分析 显示阿莫西林/克拉维酸和氨苄西林/舒巴坦对 初始微量稀释的相关性程度较低 药敏试验程序。这种差异得到了以下方面的证实 重新测试有代表性的菌株，以及 另一种药敏试验程序证实了这一差异。 在分离的菌株中，75.3%对阿莫西林/克拉维酸敏感 氨苄西林/舒巴坦中间或耐药。质粒 进行指纹分析表明，大肠杆菌 分离株代表不同的菌株；因此，差异 结果并不局限于一种或几种不寻常的大肠杆菌分离株。 考虑到临床试验的结果表明体内 两个代理的等效性，似乎有可能差异 观察到的结果是建立了不适当的断点 由国家临床实验室标准委员会提供。这个 对所有耐氨苯西林的大肠埃希菌进行1-2小时检测 年度期间正在进行中。

This project's principal focus has been to investigate the in vitro susceptibility of ampicillin-resistant Escherichia coli to amoxicillin/clavulanate and ampicillin/sulbactam. These two antibiotic-beta lactamase inhibitor combinations have been stated to be comparable in their clinical efficacy and therefore should be comparable in their in vitro susceptibility results. A lack of correlation of routine susceptibility test results between these two agents was noted in clinical isolates of ampicillin-resistant E. coli from National Institutes of Health patients. The reproducibility of the results was assessed by repeating the sensitivity test procedure on the isolates and the validity was further investigated by performing susceptibility testing by other methods. Susceptibility results of 182 ampicillin-resistant isolates revealed that amoxicillin/ clavulanate and ampicillin/sulbactam had a low degree of correlation by the initial microdilution susceptibility testing procedure. This discrepancy was confirmed by retesting representative isolates, and the validity of the discrepancy was confirmed by another susceptibility test procedure. Of the isolates, 75.3 percent were amoxicillin/clavulanate sensitive and ampicillin/sulbactam intermediate or resistant. Plasmid fingerprinting was performed to demonstrate that the E. coli isolates represented different strains; therefore, the discrepant results were not limited to one or a few unusual E. coli isolates. Given the results of clinical trials that suggest the in vivo equivalence of both agents, it seems probable that the discrepancies observed are a consequence of inappropriate break points established by the National Committee for Clinical Laboratory Standards. The assessment of all ampicillin-resistant E. coli isolated during a 1- year period is in progress.