Jorgensen J H, McElmeel M L, Crawford S A
Department of Pathology, The University of Texas Health Science Center, San Antonio 78284-7750, USA.
J Clin Microbiol. 1998 Mar;36(3):788-91. doi: 10.1128/JCM.36.3.788-791.1998.
The MicroScan MICroSTREP panel is a recently marketed frozen broth microdilution panel for susceptibility testing of various streptococci, including Streptococcus pneumoniae. The panel contains 10 antimicrobial agents in cation-adjusted Mueller-Hinton broth supplemented with 3% lysed horse blood, similar in concept to the National Committee for Clinical Laboratory Standards (NCCLS) reference broth microdilution method for testing streptococci. A group of 210 isolates of S. pneumoniae were selected to include isolates with previously documented resistance to agents incorporated in the MICroSTREP panel, as well as recent invasive clinical isolates. All isolates were tested simultaneously with the MICroSTREP panel and an NCCLS reference panel whose drug concentrations were prepared to coincide with those of the MICroSTREP panel. Of the 210 isolates, 5 failed to grow in the MICroSTREP panel; 3 of those also did not grow in the reference panel. Essential agreement of MICs determined by the two methods (test MIC +/- one dilution of the reference MIC) was 99.6% overall and ranged from 98.0% with chloramphenicol to 100% with penicillin, ceftriaxone, erythromycin, tetracycline, and vancomycin. There were no very major or major interpretive category errors resulting from the MICroSTREP panel tests. Minor interpretive category errors ranged from 12.2% with cefotaxime and 9.8% with ceftriaxone (due mainly to clustering of MICs for the selected strains near the breakpoints) to 0% with chloramphenicol and vancomycin. These results indicate that the MicroScan MICroSTREP frozen panels provide susceptibility results with pneumococci that are essentially equivalent to results derived by the NCCLS reference broth microdilution procedure.
MicroScan MICroSTREP药敏板是一种最近上市的用于多种链球菌（包括肺炎链球菌）药敏试验的冷冻肉汤微量稀释药敏板。该药敏板在阳离子调整的Mueller-Hinton肉汤中含有10种抗菌药物，并添加了3%的裂解马血，其概念与美国国家临床实验室标准委员会（NCCLS）检测链球菌的参考肉汤微量稀释法相似。选择了一组210株肺炎链球菌分离株，包括之前记录对MICroSTREP药敏板中所含药物耐药的分离株以及近期侵袭性临床分离株。所有分离株同时使用MICroSTREP药敏板和NCCLS参考药敏板进行检测，后者的药物浓度与MICroSTREP药敏板的药物浓度一致。在这210株分离株中，有5株在MICroSTREP药敏板中未生长；其中3株在参考药敏板中也未生长。两种方法测定的最低抑菌浓度（试验最低抑菌浓度±参考最低抑菌浓度的一个稀释度）的基本一致性总体为99.6%，范围从氯霉素的98.0%到青霉素、头孢曲松、红霉素、四环素和万古霉素的100%。MICroSTREP药敏板试验未产生极重大或重大解释类别错误。轻微解释类别错误范围从头孢噻肟的12.2%和头孢曲松的9.8%（主要由于所选菌株的最低抑菌浓度在断点附近聚集）到氯霉素和万古霉素的0%。这些结果表明，MicroScan MICroSTREP冷冻药敏板提供的肺炎链球菌药敏结果与NCCLS参考肉汤微量稀释程序得出的结果基本相当。
