产ESBLs的肺炎克雷伯菌耐药性及脉冲场凝胶电泳分型研究

Study on the antibiotic resistance of extended-spectrum β-lactamases (ESBLs)-producing Klebsiella pneumoniae and the pulsed-field gel electrophoresis(PFGE) typing

目的探讨产超广谱β-内酰胺酶(extended-spectrum β-lactamases,ESBLs)肺炎克雷伯菌的耐药性状况和分子流行病学特点。方法采用Kerby-Bauer纸片扩散法测定49株临床分离的产ESBLs肺炎克雷伯菌对19种抗菌药物的耐药性;并采用脉冲场凝胶电泳(PFGE)技术对其做同源性分析。结果49株产ESBLs肺炎克雷伯菌对美罗培南和亚胺培南敏感率达100%,对其他17种抗菌药物均表现不同程度耐药;PFGE图谱有6组(A￣F),以A型(27株)、B型(10株)、C型(9株)流行为主,49株产ESBLs肺炎克雷伯菌中共有19株和重症监护病房(ICU)相关,占38.8%,流行菌株在各病房之间传播。结论产ESBLs肺炎克雷伯菌呈多重耐药,其对美罗培南和亚胺培南的敏感率为100%,可作为治疗感染的首选药物,其他药物可根据药敏结果选择;浙江大学医学院附属第一医院在2006年2-8月有产ESBLs肺炎克雷伯菌流行,ICU是高发区域,普外科、呼吸内科、综合病房和干部病房中的分离率也较高,需加强检测和控制。

Objective The study was conducted to explore the antibiotic resistance and molecular epidemiological characteristics of ESBLs-producing Klebsiella pneumoniae. Methods The Kirby-Bauer disk diffusion test was conducted in 49 isolates of ESBLs-producing Klebsiella pneumoniae to determine their resistance to 19 kinds of antibacterial agents. Homology analysis was done using PFGE （Pulsed-field gel electrophoresis）. Results The sensitivity of 49 ESBLs-producing Klebsiella pneumoniae isolates to meropenem and Imipenem was 100%, whereas various degrees of resistance to other 17 kinds of antibiotics were revealed in the study. Six different PFGE types （A-F） were found among the 49 isolates, most of them being type A （27 strains） , followed by type B （10 strains） and C（9 strains）. There were 19 isolates associated with the intensive care unit （ICU）, accounting for 38.8%. The epidemic strains spread over different wards. Conclusion ESBLs-producing Klebsiella pneumoniae were multiresistant, whereas their sensitivity to meropenem and Imipenem was 100%, which made both agents the first choice to control ESBLs-producing Klebsiella pneumoniae infections. Alternative administration could be adopted based on the results of drug sensitivity test. An ESBLs-producing Klebsiella pneumoniae epidemic was reported in the First Affiliated Hospital to Zhejiang University Medical College from Feb to Aug, 2006. ICU ward is the high incident region of ESBLs-producing Klebsiella pneumoniae infection. High isolation rates were found in general surgery, respiratory, comprehensive and cadre wards. Therefore, detection and control of relevant strains and associated infections should be enhanced in future.