Richter Sandra S, Karichu James, Otiso Joshua, Van Heule Hillary, Keller George, Cober Eric, Rojas Laura J, Hujer Andrea M, Hujer Kristine M, Marshall Steve, Perez Frederico, Rudin Susan D, Domitrovic T Nicholas, Kaye Keith S, Salata Robert, van Duin David, Bonomo Robert A
Cleveland Clinic, Cleveland, OH,.
Cleveland Clinic, Cleveland, OH.
Diagn Microbiol Infect Dis. 2018 May;91(1):89-92. doi: 10.1016/j.diagmicrobio.2018.01.005. Epub 2018 Jan 9.
Colistin and polymyxin B MICs were determined for 106 carbapenem-resistant Klebsiella pneumoniae (CR-Kp) isolates using Sensititre Research Use Only GNX2F plates (Thermo Fisher) and compared to CLSI broth macrodilution (BMD) as the reference method. For colistin, EUCAST breakpoints were applied and testing of isolates with very major (VM) errors was repeated in duplicate by both methods to determine a majority result. Essential agreement (MIC ± one dilution) of GNX2F with the reference method was 97.1% for polymyxin B and 92.5% for colistin (7 VM errors, 22.6%). After discrepancy testing, there were 28 colistin resistant isolates by BMD and essential agreement was 94.3% with 4 VM errors (14.3%). Colistin and polymyxin B GNX2F results showed acceptable essential agreement with BMD for MICS without interpretation. Colistin VM errors with EUCAST breakpoints were due to MIC variability in the 2 to 4 μg/mL range that could be addressed by establishing an intermediate category.
使用Sensititre仅用于研究的GNX2F平板（赛默飞世尔公司）对106株耐碳青霉烯类肺炎克雷伯菌（CR-Kp）分离株测定了黏菌素和多黏菌素B的最低抑菌浓度（MIC），并与作为参考方法的美国临床和实验室标准协会（CLSI）肉汤稀释法（BMD）进行比较。对于黏菌素，采用欧洲抗菌药物敏感性试验委员会（EUCAST）的断点标准，对出现极重大（VM）错误的分离株，两种方法均重复检测两次以确定多数结果。GNX2F平板法与参考方法的基本一致率（MIC±一个稀释度），多黏菌素B为97.1%，黏菌素为92.5%（7个VM错误，占22.6%）。经过差异检测，BMD法检测出28株黏菌素耐药分离株，基本一致率为94.3%，有4个VM错误（占14.3%）。黏菌素和多黏菌素B的GNX2F平板法结果显示，对于未进行判读的MIC，与BMD法有可接受的基本一致率。黏菌素在EUCAST断点标准下出现VM错误是由于在2至4μg/mL范围内的MIC变异性，可通过设立一个中间类别来解决。
