Pfaller M A, Beach M L, Gordon K A, Jones R N
University of Iowa College of Medicine, Iowa City, USA.
J Chemother. 2002 Feb;14(1):13-8.
The study was initiated to determine the in vitro activity and MIC/disk test comparisons of BMS284756, a new des-fluoro(6)-quinolone, against isolates of staphylococci and enterococci from the SENTRY Antimicrobial Surveillance Program, 2000. Isolates were tested by reference broth microdilution and standardized disk diffusion methods. Against 3,789 strains of gram-positive cocci from the SENTRY Program (2000), the BMS284756 MIC90 and percentage susceptible at < or = 2 and < or = 4 microg/ml were: Staphylococcus aureus (4 microg/ml; 89.3 and 97.1%), coagulase-negative staphylococci (CoNS; 4 microg/ml; 86.1 and 96.0%) and enterococci (> 4 microg/ml; 62.0 and 76.2%). Also tested were selected staphylococci (300 strains) and enterococci (102 strains) by two standardized methods. The activity of BMS284756 was highly correlated with oxacillin resistance among staphylococci. Oxacillin-susceptible staphylococci were all inhibited by BMS284756 at < or = 0.5 microg/ml, whereas oxacillin-resistant strains required inhibitory concentrations of > or = 1 microg/ml. Excellent correlation was observed between the MIC and 5-microg disk zone diameter for staphylococci and enterococci (r=0.91 to 0.93). Among vancomycin-susceptible enterococci, 67% of Enterococcus faecalis, 25% of E. faecium, and 76% of other Enterococcus spp. isolates were inhibited by BMS284756 at < or = 2 microg/ml. All vancomycin-resistant enterococci (VRE; 11 E. faecalis and 15 E. faecium) were inhibited by > or = 2 microg/ml of BMS284756. Among the non-VRE, non-faecium enterococcal isolates (n=64), 62% were inhibited by < or = 0.5 microg/ml. BMS284756 showed excellent activity against oxacillin-susceptible staphylococci and moderate activity against enterococci other than VRE and E. faecium. Acceptable correlations were observed between MIC and disk test results for both tested genus groups.
开展该研究是为了确定新型去氟（6）-喹诺酮类药物BMS284756对2000年哨兵抗菌监测计划中葡萄球菌和肠球菌分离株的体外活性以及MIC/纸片试验比较。采用参考肉汤微量稀释法和标准化纸片扩散法对分离株进行检测。针对哨兵计划（2000年）中的3789株革兰氏阳性球菌，BMS284756的MIC90以及在≤2μg/ml和≤4μg/ml时的敏感百分比分别为：金黄色葡萄球菌（4μg/ml；89.3%和97.1%）、凝固酶阴性葡萄球菌（CoNS；4μg/ml；86.1%和96.0%）和肠球菌（＞4μg/ml；62.0%和76.2%）。还通过两种标准化方法对选定的葡萄球菌（300株）和肠球菌（102株）进行了检测。BMS284756的活性与葡萄球菌中的苯唑西林耐药性高度相关。苯唑西林敏感的葡萄球菌在≤0.5μg/ml时均被BMS284756抑制，而苯唑西林耐药菌株则需要≥1μg/ml的抑菌浓度。观察到葡萄球菌和肠球菌的MIC与5μg纸片抑菌圈直径之间具有良好的相关性（r=0.91至0.93）。在对万古霉素敏感的肠球菌中，67%的粪肠球菌、25%的屎肠球菌以及76%的其他肠球菌属分离株在≤2μg/ml时被BMS284756抑制。所有万古霉素耐药肠球菌（VRE；11株粪肠球菌和15株屎肠球菌）在≥2μg/ml的BMS284756作用下被抑制。在非VRE、非屎肠球菌的肠球菌分离株（n=64）中，62%在≤0.
