摘要
目的分析杭州市肺炎链球菌临床菌株parC/parE和gyrA/gyrB喹诺酮耐药决定区(QRDR)突变,及与喹诺酮类药物敏感性下降的相关性。方法采用琼脂稀释法检测37株临床菌株对8种抗生素的最小抑菌浓度(MIC),PCR法扩增目的基因并测序。结果对左氧氟沙星、莫西沙星和万古霉素全部敏感,其余抗生素耐药率都〉60%,对左氧氟沙星MIC≤1 mg/L和MIC=2 mg/L分别有21株和16株。所有菌株gyrA/gyrB的均无突变,其中3株parC/parE也未见突变;34株临床菌株parE有突变,其中10株同时存在parC基因突变,parE基因分别有33株和8株发生I460V和D435N突变,parC基因有8株发生S79F突变。MIC=2 mg/L的菌株中parC/parE基因同时突变、S79F和/或D435N突变明显高于MIC≤1 mg/L菌株(χ2=4.2~6.2,P〈0.05)。结论本地区未发现左氧氟沙星耐药肺炎链球菌株,parC/parE同时突变、S79F和/或D435N突变使左氧氟沙星MIC提高。监测临床菌株parC/parE和gyrA/gyrB突变情况,防止药物诱导耐药株的产生。
Objective To analyze the correlation between the mutations in the quinolone - resistance - determining - region (QRDR) within genes ofparC/parE and gyrA/gyrB in streptococcus pneumoniae clinical isolates andthe decline of thelevofloxacin' s susceptivity in Hangzhou. Methods MICs of 8 antimierobials were determined by agar dilution method, PCR and DNA sequencing were conducted to analyze QRDR associated genes ofparC/parE and gyrA/gyrB in 37 isolates. Results All the isolates were susceptible to levofloxacin, moxifloxacin and vancomycin. The rest of antibiotic resistance rate were greater than 60% MIC ~〈 1 mg/L and MIC = 2 mg/L to levofloxacin were 21 and 16 isolates, respectively. All the isolates were no mutation of gyrA/gyrB genes, three of them were no mutation ofparC/parE genes. 34 isolates had mutations in pare gene, 10 of them had mutations in parC gene. 33 and 8 isolates had I460V and D435N mutations in parE gene, respectively. 8 isolates had S79F mutations in parC gene. Mutations in parC/parE genes at the same time,mutation of S79F and/or D435N in MIC =2 mg/L isolates were significantly higher than that MIC〈1 mg/L of isolates0(2 =4.2-6.2,P〈0.05). Conclusion No isolate was found resistant to quinolones, The MIC of levofloxacin were improved wfien mutations in parC and parE, $79F and/or D435N occurred. Monitoring parC/parE said and gyrA/gyrB mutations of isolates situation in order to prevent the formation of resistant isolates led by the medicine.
出处
《中国卫生检验杂志》
北大核心
2014年第17期2566-2569,共4页
Chinese Journal of Health Laboratory Technology
基金
国家自然科学基金项目(81271893)
浙江省自然科学基金项目(LY12H19002)
浙江省医药卫生科技计划项目(2011KYA005)
关键词
肺炎链球菌
基因突变
喹诺酮类
耐药
最小抑菌浓度
Streptococcus pneumoniae
Gene Mutation
Quinolones/resistance
Minimal inhibitory concentration(MIC)