Woodford Neil, Reynolds Rosy, Turton Jane, Scott Fiona, Sinclair Alistair, Williams Andrea, Livermore David
Antibiotic Resistance Monitoring and Reference Laboratory, Specialist and Reference Microbiology Division, Health Protection Agency-Colindale, London NW9 5HT UK.
J Antimicrob Chemother. 2003 Oct;52(4):711-4. doi: 10.1093/jac/dkg408. Epub 2003 Aug 13.
A strong association was observed between high-level resistance to ciprofloxacin and gentamicin for isolates of Enterococcus faecalis collected in the UK and Ireland as part of the BSAC Bacteraemia Resistance Surveillance Programme, 2001. Thus, 60 of 66 E. faecalis isolates with gentamicin MICs > or =512 mg/L were highly resistant to ciprofloxacin (MICs > or =32 mg/L), compared with only three of 83 E. faecalis isolates with normal gentamicin susceptibility (MICs < or =128 mg/L) (P<0.0001). Pulsed-field gel electrophoresis of SmaI-digested genomic DNA was used to investigate 38 representative E. faecalis isolates with the double resistance from 18 hospitals. Based on the criterion of > or =80% banding pattern similarity, two large clusters were observed: cluster 1 included 14 isolates, from seven hospitals, that were related at 84.8% similarity; cluster 2 included 10 isolates, from six hospitals, that were related at 83.3% similarity. Sporadic isolates and small clusters with the double resistance were also observed, but were not closely related to those in clusters 1 and 2. Further work is needed to characterize these two 'epidemic' E. faecalis strains and to investigate the presence of virulence genes.
作为2001年英国抗菌化疗协会（BSAC）菌血症耐药性监测计划的一部分，对在英国和爱尔兰收集的粪肠球菌分离株进行检测，结果发现对环丙沙星和庆大霉素的高水平耐药性之间存在密切关联。因此，66株庆大霉素MIC≥512mg/L的粪肠球菌分离株中，有60株对环丙沙星高度耐药（MIC≥32mg/L），而83株庆大霉素敏感性正常（MIC≤128mg/L）的粪肠球菌分离株中只有3株对环丙沙星高度耐药（P<0.0001）。采用脉冲场凝胶电泳技术对来自18家医院的38株具有双重耐药性的代表性粪肠球菌分离株进行了研究。根据条带模式相似度≥80%的标准，观察到两个大的聚类：聚类1包括来自7家医院的14株分离株，相似度为84.8%；聚类2包括来自6家医院的10株分离株，相似度为83.3%。也观察到了具有双重耐药性的散在分离株和小聚类，但它们与聚类1和聚类2中的分离株没有密切关系。需要进一步开展工作来鉴定这两种“流行”的粪肠球菌菌株，并调查毒力基因的存在情况。
