Sanchez M L, Barrett M S, Jones R N
Anti-Infectives Research Centre, Department of Pathology, University of Iowa, College of Medicine, Iowa City 52242.
J Clin Microbiol. 1992 Nov;30(11):3030-2. doi: 10.1128/jcm.30.11.3030-3032.1992.
The E test and the reference agar dilution methods were compared for detecting high-level aminoglycoside resistance (HLAR) among 71 selected clinical isolates, including 62 Enterococcus faecalis and 9 Enterococcus faecium isolates. High-level gentamicin resistance alone was found in 11% (5 E. faecalis and 3 E. faecium strains) and high-level streptomycin resistance was found in 42% (28 E. faecalis, 2 E. faecium strains) of the strains tested, and 31% of the strains demonstrated high-level resistance to both antimicrobial agents (21 E. faecalis and 1 E. faecium strains). The E test detected all HLAR populations, but the streptomycin strip may require recalibration to achieve absolute MIC comparisons with the reference value (twofold less) or the use of an alternative interpretive resistance breakpoint, e.g., > 1,000 micrograms/ml. By the E test, MIC results indicate that ampicillin, imipenem, penicillin, piperacillin, and vancomycin remain active against the HLAR E. faecalis isolates; however, these tested drugs were less effective on the HLAR E. faecium isolates (< 50%).
对71株选定的临床分离株（包括62株粪肠球菌和9株屎肠球菌分离株）进行E试验和参考琼脂稀释法比较，以检测高水平氨基糖苷类耐药性（HLAR）。在所测试的菌株中，仅发现11%（5株粪肠球菌和3株屎肠球菌菌株）对高水平庆大霉素耐药，42%（28株粪肠球菌、2株屎肠球菌菌株）对高水平链霉素耐药，31%的菌株对两种抗菌药物均表现出高水平耐药（21株粪肠球菌和1株屎肠球菌菌株）。E试验检测到了所有HLAR菌群体，但链霉素试纸条可能需要重新校准，以实现与参考值（低两倍）的绝对MIC比较，或使用替代的耐药性解释断点，例如>1000微克/毫升。通过E试验，MIC结果表明氨苄西林、亚胺培南、青霉素、哌拉西林和万古霉素对HLAR粪肠球菌分离株仍有活性；然而，这些受试药物对HLAR屎肠球菌分离株的效果较差（<50%）。
