Shamina O V, Kryzhanovskaya O A, Lazareva A V, Polikarpova S V, Karaseva O V, Chebotar I V, Mayanskiy N A
Federal State Autonomous Institution «National Medical Research Center for Children's Health» of the Russian Federation Ministry of Health, 119991, Moscow, Russia.
State Budgetary Healthcare Institution «Municipal Clinical Hospital № 15 named O.M. Filatov» Department of Health of Moscow, 111539, Moscow, Russia.
Klin Lab Diagn. 2018;63(10):646-650. doi: 10.18821/0869-2084-2018-63-10-646-650.
In recent years, because of carbapenemase spreading in Klebsiella pneumoniae strains, the antibiotic of reserve group, colistin, is increasingly prescribed. In vitro testing of colistin susceptibility in everyday practice has a number of difficulties due to the cationic properties of molecule and weak diffusion into agar. Therefore it is recommended to use the reference Broth Microdilution Method (BMD) for determination of the Minimum Inhibitory Concentration (MIC) for colistin. The purpose of the study was to determine susceptibility to colistin in 119 carbapenem-resistant K. pneumoniae (CRKp) which were isolated from the patients at three hospitals in Moscow in 2012-2016 by the broth microdilution method (BMD) and to compare these data with the ones obtained by epsilometer test (E-test) and VITEK 2 Compact. The proportion of resistant isolates (MIC>2 mg/L) was 52%, 39%, 35% respectively. Both commercial methods demonstrated a high level of the very major error (VME) that was 26% for the E-test method and 34% for the VITEK 2 Compact. The values of categorical agreement and essential agreement (CA, EA) were less than 90%. A single major error (ME) was detected for the VITEK 2 Compact. In conclusion, results of both commercial tests for determination of MIC for colistin showed differences with the results of the reference BMD. It is necessary for clinical laboratories to be aware about this discrepancy and to use E-tests and VITEK 2 Compact with caution to determine colistin susceptibility.
近年来，由于碳青霉烯酶在肺炎克雷伯菌菌株中传播，作为储备组抗生素的黏菌素的使用越来越普遍。在日常实践中，由于黏菌素分子的阳离子特性以及其在琼脂中的扩散性较弱，对其进行体外药敏试验存在诸多困难。因此，推荐使用参考肉汤微量稀释法（BMD）来测定黏菌素的最低抑菌浓度（MIC）。本研究的目的是通过肉汤微量稀释法（BMD）测定2012 - 2016年从莫斯科三家医院的患者中分离出的119株耐碳青霉烯肺炎克雷伯菌（CRKp）对黏菌素的敏感性，并将这些数据与通过纸片扩散法（E-test）和VITEK 2 Compact获得的数据进行比较。耐药菌株（MIC>2 mg/L）的比例分别为52%、39%、35%。两种商业方法均显示出较高水平的重大错误（VME），E-test方法为26%，VITEK 2 Compact为34%。分类一致性和基本一致性（CA，EA）值均低于90%。VITEK 2 Compact检测到一个单一重大错误（ME）。总之，两种用于测定黏菌素MIC的商业测试结果与参考BMD结果存在差异。临床实验室有必要意识到这种差异，并谨慎使用E-test和VITEK 2 Compact来确定黏菌素的敏感性。
