痰标本中质粒介导喹诺酮耐药基因qnr在肺炎克雷伯菌中的分布特征及耐药分析

目的:了解从痰标本中分离出的肺炎克雷伯菌对16种抗菌药物的耐药性,以及研究由质粒介导的喹诺酮类耐药基因qnr在肺炎克雷伯菌中的存在情况。方法:用PCR及直接测序的方法对135株肺炎克雷伯菌进行qnr基因检测,并用K-B纸片法检测其对16种抗菌药物的体外抗菌活性。另外,用琼脂平皿二倍稀释法检测阳性菌株对左氧氟沙星的MIC值。结果:135株肺炎克雷伯菌中,9株(6.6%)检出qnr基因。阳性菌株均对亚胺培南敏感且对多种抗生素耐药,其中2株qnr阳性菌株对左氧氟沙星敏感。结论:肺炎克雷伯菌中存在质粒介导喹诺酮类耐药基因qnr基因,qnr阳性菌株呈现多重耐药。临床工作中,应加强对耐药基因的监测,降低细菌耐药的发生。

Distribution characteristics and drug resistant analysis of plasmid-mediated quinolone drug resistant gene qnr of Klebsiella pneumoniae isolates separated from sputum samples in our hospital

OBJECTIVE To explore the drug resistant characteristics to 16 kinds of antibiotics and the distribution of plasmid-mediated quinolone drug resistant gene qnr of Klebsiella pneumoniae isolates separated from sputum samples.METHODS By using PCR and direct sequencing method,the gene qnr of Klebsiella pneumoniae was detected.Then,the antibacterial activities of 16 kinds of antibiotics on Klebsiella pneumoniae isolates in vitro were studied.Finally,was detected the MIC value of levofloxacin on gene qnr positive Klebsiella pneumoniae isolates with agar plate two-fold dilution method.RESULTS Among all 135 Klebsiella pneumoniae isolates,9 Klebsiella pneumoniae isolates was determined with gene qnr.These isolates were all sensitive to imipenem and resistant to the other kinds of antibiotics.There were also 2 Klebsiella pneumoniae isolates sensitive to levofloxacin.CONCLUSION There are plasmid-mediated quinolone drug resistant gene qnr in our hospital.Qnr positive isolates were multi-drug resistant.In clinic,we should pay attention to monitor on drug resistant genes and decrease the frequencies of drug resistant.