Infectious Diseases Laboratory, 4th Department of Internal Medicine, National and Kapodistrian University of Athens, Athens, Greece.
Infectious Diseases Laboratory, 4th Department of Internal Medicine, National and Kapodistrian University of Athens, Athens, Greece.
J Glob Antimicrob Resist. 2018 Dec;15:123-126. doi: 10.1016/j.jgar.2018.07.006. Epub 2018 Jul 20.
Colistin is often the last option to treat infections caused by multidrug-resistant micro-organisms such as carbapenem-resistant Klebsiella pneumoniae. Antimicrobial susceptibility testing of colistin has been fraught with difficulties, which resulted in the need for updated recommendations from the CLSI and EUCAST. Both committees proposed that the ISO 20776-1-2016 standard broth microdilution (BMD) method must be the preferred method for colistin minimum inhibitory concentration (MIC) testing. The objective of this study was to evaluate the commercial ComASP™ Colistin (Liofilchem srl), a compact panel containing the antibiotic in seven two-fold dilutions (0.25-16mg/L), using frozen BMD plates (according to CLSI) as reference.
Colistin susceptibility testing was performed on a nationwide collection of 392 carbapenem-resistant K. pneumoniae isolates using BMD according to the CLSI and by ComASP™ Colistin according to the manufacturer's recommendations. Susceptibility test results were interpreted according to EUCAST v.7.1 breakpoints (2017). Colistin was active in vitro against 251 K. pneumoniae isolates (64.0%) with an MIC range of 0.5mg/L to >64mg/L and MIC values of 1/64mg/L. Essential and categorical agreements were calculated according to ISO20776-2.
ComASP™ Colistin showed high levels of overall/evaluable essential agreement (94.9%/93.6%) and categorical agreement (97.2%), with very major errors in 0.7% (1/141 colistin-resistant), and met the current acceptance criteria proposed by the CLSI. Ten major errors were observed [4.0% (10/251) colistin-susceptible], three of which were within essential agreement.
ComASP™ Colistin is a commercial BMD method that reliably determined colistin MICs in a large collection of carbapenem-resistant K. pneumoniae isolates.
多药耐药微生物引起的感染，例如碳青霉烯类耐药肺炎克雷伯菌，常常最后才使用黏菌素进行治疗。黏菌素的药敏试验一直存在困难，这导致 CLSI 和 EUCAST 需要更新推荐意见。两个委员会都提出，ISO 20776-1-2016 标准肉汤微量稀释（BMD）法必须是黏菌素最低抑菌浓度（MIC）检测的首选方法。本研究的目的是评估商业 ComASP™黏菌素（Liofilchem srl），这是一个包含七种两倍稀释度（0.25-16mg/L）抗生素的紧凑试剂盒，使用冷冻 BMD 板（根据 CLSI）作为参考。
使用 BMD 根据 CLSI 和根据制造商建议使用 ComASP™黏菌素对来自全国范围内的 392 株碳青霉烯类耐药肺炎克雷伯菌分离株进行黏菌素药敏试验。根据 EUCAST v.7.1 折点（2017 年）解释药敏试验结果。黏菌素对 251 株肺炎克雷伯菌（64.0%）具有体外活性，MIC 范围为 0.5mg/L 至＞64mg/L，MIC 值为 1/64mg/L。根据 ISO20776-2 计算了基本和分类一致率。
ComASP™黏菌素显示出较高的总体/可评估基本一致率（94.9%/93.6%）和分类一致率（97.2%），仅有 0.7%（1/141 株黏菌素耐药）出现非常大的错误，符合 CLSI 提出的当前接受标准。观察到 10 个主要错误[4.0%（10/251 株黏菌素敏感）]，其中 3 个在基本一致范围内。
ComASP™黏菌素是一种商业 BMD 方法，可在大量碳青霉烯类耐药肺炎克雷伯菌分离株中可靠地确定黏菌素 MIC。
