粪肠球菌对泰利霉素药物敏感性与 耐药基因erm的分布

目的了解粪肠球菌对泰利霉素和其他常用抗菌药物的耐药性,以及泰利霉素耐药与红霉素耐药相关基因ermA、ermB、ermC之间的关系。方法对本院2010-2016年从各种临床标本收集鉴定的320株粪肠球菌,用微量肉汤稀释法测定这些菌株对泰利霉素及8种临床常用抗菌药物的最小抑菌浓度,并用PCR法检测耐药基因ermA、ermB、ermC的分布。结果320株粪肠球菌对泰利霉素中介耐药26株,耐药138株,耐药率达51.3%;对红霉素耐药率达95.6%,泰利霉素抗粪肠球菌效果优于红霉素。对利奈唑胺、万古霉素、呋喃妥因和氨苄西林耐药率分别为15.6%、0.6%、2.2%和0.6%。共10株(3.1%)携带ermA基因,207株(64.7%)携带ermB基因,对泰利霉素中介组中有23株ermB基因阳性,耐药组有131株ermB基因阳性,仅1株(0.3%)ermC基因阳性,该菌同时携带ermB基因。结论粪肠球菌对泰利霉素已有较高耐药率。粪肠球菌对泰利霉素MIC值改变与ermB基因密切相关,与ermA、ermC基因无明显相关性。

Antibiotic susceptibility of Enterococcus faecalis to Telithromycin and distribution of resistance relevant gene erm

Abstract: Objectives To determine the resistance rates of Enterococcus faecalis to commonly used antibiotics including Telithromycin, and explore the relationships between the resistance of E.faecalis to Telithromycin and the distribution of Erythromycin-resistance relevant genes ermA, ermB and ermC. Methods 320 strains of E.faecalis were isolated from different clinical specimens during 2010 - 2016, and micro-broth dilution method was used to detect the MICs of Telithromycin and other 8 antibiotics. PCR was performed to detect the distribution of resistance genes ermA, ermB and ermC. Results 26 strains of E. faecalis were intermediate-resistant while 138 strains resistant to Telithromycin, at a resistant rate up to 51.3%. 95.6% of the E. faecalis strains were resistant to Erythromycin. Telithromycin was superior to Erythromycin in term of anti-E. faecalis effect. The resistance rates of E. faecalis to Linezolid, Vancomycin, Nitrofurantoin and Ampicillin were 15.6%, 0.6%, 2.2% and 0.6% respectively. 10 (3.1%) strains carried ermA and 207 (64.7%) strains carried ermB. There were 23 ermB positive strains in the intermediate-resistance group, and 131 ermB positive ones in the resistance group. There was only 1 (0.3%) ermC positive strain which carried ermB too. Conclusion E. faecalis has a high resistance rate to Telithromycin. The changing MIC of Telithromycin to E. faecalis is closely related to ermB gene.