Medical Technology School of Xuzhou Medical University, Xuzhou 221004, China.
Medical Technology School of Xuzhou Medical University, Xuzhou 221004, China; Department of Laboratory Medicine, The Affiliated Hospital of Xuzhou Medical University, Xuzhou 221002, China.
J Glob Antimicrob Resist. 2018 Jun;13:11-19. doi: 10.1016/j.jgar.2017.10.018. Epub 2017 Oct 31.
Enterococcus is a significant pathogen in numerous infections, particularly in nosocomial infections, and is thus a great challenge to clinicians. Linezolid (LNZ), an oxazolidinone antibiotic, is an important therapeutic option for infections caused by Gram-positive bacterial pathogens, especially vancomycin-resistant enterococci. A systematic review was performed of the available literature on LNZ-resistant enterococci (LRE) to characterise these infections with respect to epidemiological, microbiological and clinical features. The results validated the potency of LNZ against enterococcal infections, with a sustained susceptibility rate of 99.8% in ZAAPS and 99.2% in LEADER surveillance programmes. Patients with LRE had been predominantly exposed to LNZ prior to isolation of LRE, with a mean treatment duration of 29.8±48.8days for Enterococcus faecalis and 23.1±21.4days for Enterococcus faecium. Paradoxically, LRE could also develop in patients without prior LNZ exposure. LNZ resistance was attributed to 23S rRNA (G2576T) mutations (51.2% of E. faecalis and 80.5% of E. faecium) as well as presence of the cfr gene (4.7% and 4.8%, respectively), which could transfer horizontally among the strains. In addition to the cfr gene, 32 cases of optrA-positive LRE were identified. Further study is required to determine the prevalence of novel resistance genes. The emergence of LRE thus hampers the treatment of such infections, which warrants worldwide surveillance.
肠球菌是许多感染，尤其是医院获得性感染的重要病原体，因此对临床医生构成了巨大挑战。利奈唑胺（LNZ）是一种恶唑烷酮类抗生素，是治疗革兰阳性细菌病原体感染，特别是耐万古霉素肠球菌感染的重要治疗选择。对 LNZ 耐药肠球菌（LRE）的现有文献进行了系统评价，以描述这些感染的流行病学、微生物学和临床特征。结果证实了 LNZ 对肠球菌感染的有效性，在 ZAAPS 和 LEADER 监测计划中，对屎肠球菌的持续敏感性率分别为 99.8%和 99.2%。在分离出 LRE 之前，LRE 患者主要接触过 LNZ，屎肠球菌的平均治疗持续时间为 29.8±48.8 天，粪肠球菌为 23.1±21.4 天。矛盾的是，没有 LNZ 暴露史的患者也可能产生 LRE。LRE 的产生归因于 23S rRNA（G2576T）突变（51.2%的屎肠球菌和 80.5%的粪肠球菌）以及 cfr 基因的存在（分别为 4.7%和 4.8%），该基因可在菌株之间水平转移。除了 cfr 基因外，还发现了 32 例 optrA 阳性的 LRE。需要进一步研究来确定新型耐药基因的流行情况。LRE 的出现因此阻碍了这些感染的治疗，这需要全球范围内的监测。
