Sosa A, Tally F P, Jacobus N V, Gorbach S L
Antimicrob Agents Chemother. 1982 Nov;22(5):771-4. doi: 10.1128/AAC.22.5.771.
Clindamycin resistance in Bacteroides fragilis was examined in 507 strains isolated from 1973 to 1981. Three groups were recognized: highly susceptible (minimum inhibitory concentration [MIC] less than or equal to 0.125 microgram/ml), intermediately susceptible (MIC = 0.25 to 4 micrograms/ml), and highly resistant to (MIC greater than or equal to 8 microgram/ml). The incidence of high-level resistance (1.8%) had not changed during this period. Only 8 of 17 isolates reputed to be highly clindamycin resistant that were referred to our laboratory proved to be highly resistant (MICs greater than or equal to 32 microgram/ml), whereas the other 9 were intermediately susceptible. Analysis of 2- and 10-microgram clindamycin disks for determining the susceptibility of B. fragilis revealed a high false-resistance rate with the 2-microgram disk, most errors occurring with the intermediate group. There was no false resistance with the 10-microgram disk. When disk diffusion susceptibility of B. fragilis is employed, we recommend the 10-microgram disk to predict accurately the susceptibility of B. fragilis to clindamycin.
对1973年至1981年间分离出的507株脆弱拟杆菌进行了克林霉素耐药性检测。分为三组：高度敏感（最低抑菌浓度[MIC]小于或等于0.125微克/毫升）、中度敏感（MIC = 0.25至4微克/毫升）和高度耐药（MIC大于或等于8微克/毫升）。在此期间，高水平耐药的发生率（1.8%）没有变化。送至我们实验室的17株据称对克林霉素高度耐药的分离株中，只有8株被证明高度耐药（MIC大于或等于32微克/毫升），而其他9株为中度敏感。分析用于检测脆弱拟杆菌敏感性的2微克和10微克克林霉素纸片发现，2微克纸片的假耐药率很高，大多数错误发生在中度敏感组。10微克纸片没有假耐药情况。当采用纸片扩散法检测脆弱拟杆菌的敏感性时，我们建议使用10微克纸片来准确预测脆弱拟杆菌对克林霉素的敏感性。
