Tritz D M, Iwen P C, Woods G L
Department of Pathology and Microbiology, University of Nebraska Medical Center, Omaha 68198.
J Clin Microbiol. 1990 Jun;28(6):1477-8. doi: 10.1128/jcm.28.6.1477-1478.1990.
Emerging drug resistance of the enterococci necessitates differentiation from group D streptococci and accurate species identification. MicroScan (Baxter Healthcare Corp., West Sacramento, Calif.) has recently developed a microdilution system for identification and antibiotic susceptibility testing of gram-positive cocci. To evaluate the ability of this system to identify Enterococcus species, 100 isolate identified as enterococci by MicroScan were tested by conventional media and 60 isolates of streptococci were tested by MicroScan. Incubation times for conventional and MicroScan methods were 96 and 18 to 24 h, respectively. For 94 strains of enterococci (77 Enterococcus faecalis, 14 Enterococcus faecium, and 3 Enterococcus durans), identification by conventional media and MicroScan agreed. Of the remaining six isolates, four were identified as E. faecalis and two were identified as E. durans by MicroScan, whereas by conventional media the four E. faecalis isolates were identified as Enterococcus solitarius and the two E. durans isolates were identified as Enterococcus hirae. None of the 60 streptococci were identified as enterococci. MicroScan is a reliable method for identification of the commonly encountered enterococcal species E. faecalis and E. faecium; however, modifications of the system are necessary for identification of other Enterococcus species.
肠球菌新出现的耐药性使得有必要将其与D群链球菌区分开来并进行准确的菌种鉴定。MicroScan（百特医疗保健公司，加利福尼亚州西萨克拉门托）最近开发了一种用于革兰氏阳性球菌鉴定和抗生素敏感性测试的微量稀释系统。为评估该系统鉴定肠球菌菌种的能力，对100株经MicroScan鉴定为肠球菌的菌株采用传统培养基进行测试，对60株链球菌菌株采用MicroScan进行测试。传统方法和MicroScan方法的孵育时间分别为96小时和18至24小时。对于94株肠球菌（77株粪肠球菌、14株屎肠球菌和3株耐久肠球菌），传统培养基鉴定结果与MicroScan一致。在其余6株分离株中，MicroScan将4株鉴定为粪肠球菌，2株鉴定为耐久肠球菌，而通过传统培养基，4株粪肠球菌分离株被鉴定为孤立肠球菌，2株耐久肠球菌分离株被鉴定为希拉肠球菌。60株链球菌均未被鉴定为肠球菌。MicroScan是鉴定常见肠球菌菌种粪肠球菌和屎肠球菌的可靠方法；然而，该系统需要进行改进以鉴定其他肠球菌菌种。
