常见医院感染病原菌对喹诺酮类药物的耐药性

目的了解某院近几年常见医院感染病原菌分离趋势，探讨其对喹诺酮类药物的耐药变迁和耐药机制，指导临床合理用药。方法采用Vitek 32全自动微生物分析仪进行细菌鉴定，药敏试验采用琼脂扩散法(K B法)，药敏结果判读按照美国临床实验室标准化研究所(CLSI)制定的标准判读。结果2006年1月-2010年12月，该院医院感染送检标本共检出病原菌10 606株，居前5位的分别是：大肠埃希菌、金黄色葡萄球菌、铜绿假单胞菌、肺炎克雷伯菌、鲍曼不动杆菌，各年度的病原菌分布总体相差不大。药敏结果显示，此5种病原菌对喹诺酮类药物的耐药性逐年上升，其中大肠埃希菌和肺炎克雷伯菌耐药率增长较快，对环丙沙星的耐药率，分别由2006年的48.72%和48.33%上升至2010年的89.06%和81.53%（P<0.005）；对左氧氟沙星的耐药率分别由2006年的48.84%和39.77%上升至2010年的80.14%和80.64%（P<0.005）。铜绿假单胞菌对环丙沙星、左氧氟沙星和培氟沙星的耐药率也逐年上升（P<0.005）。革兰阳性球菌对喹诺酮类药物的耐药率呈缓慢上升。结论近年，医院感染常见病原菌对喹诺酮类药物的耐药性不断上升，应加强细菌耐药性的监测；临床应根据药敏试验结果合理用药。

Quinolone resistance in common pathogenic bacteria causing healthcare associated infection

ObjectiveTo investigate the isolation trends of common pathogenic bacteria in healthcare associated infection（HAI） in a hospital,evaluate the changes in antimicrobial resistance to quinolones and antimicrobial resistance mechanisms, and guide rational antimicrobial use.MethodsBacterial identification and antimicrobial susceptibility test were performed by Vitek 32 system and Kirby Bauer method respectively, and antimicrobial susceptibility test results were evaluated based on standard of US Clinical and Laboratory Standards Institute （CLSI）.ResultsFrom January 2006 to December 2010, a total of 10 606 pathogenic bacteria isolates were detected, the top 5 pathogens were Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, Klebsiella pneumoniae, and Acinetobacter baumannii, distribution of pathogens of each year varied little. Antimicrobial susceptibility test results showed that antimicrobial resistance of these 5 pathogens to quinolones increased year by year, Escherichia coli and Klebsiella pneumoniae increased most rapidly,the resistant rate to ciprofloxacin increased from 48.72% and 48.33% in 2006 to 89.06% and 81.53% in 2010 respectively （P〈0.005）, the resistance to levofloxacin increased from 48.84% and 39.77% in 2006 to 80.14% and 80.64% in 2010 respectively （P〈0.005）; the resistant rate of Pseudomonas aeruginosa to ciprofloxacin, levofloxacin, and pefloxacin also increased year by year （P〈0.005）. Antimicrobial resistant rate of gram positive cocci to quinolones increased slowly.ConclusionIn the past five years, resistance of common pathogens in HAI to quinolones were increasing, monitoring on bacterial resistance should be strengthened; clinical antimicrobial use should be based on antimicrobial susceptibility test result.