2006年1月～2007年12月败血症患者520例病原菌分布及其耐药性分析

目的 了解败血症病原菌分布及其耐药性的变化,指导临床合理用药.方法 应用全自动血培养仪对520例疑似败血症患者外周血标本进行培养,使用Vitek AMS系统对培养阳性者进行病原菌鉴定,采用K-B法进行体外药敏试验,并采用体外扩散确证法进行ESBLs检测.结果 520例外周血标本中检出107株(20.6%)病原菌,从中分离出革兰阴性菌56株(52.3%),革兰阳性菌40株(37.4%),真菌11株(10.3%).引起败血症的主要病原菌依次为大肠埃希菌(28株,26.2%)、葡萄球菌(25株,23.4%)、克雷伯菌(11株,10.3%);28株大肠埃希菌和11株克雷伯菌中分别确证ESBLs阳性菌13株和3株,检出率分别为46.4%和27.3%.ESBLs阳性菌株对多种抗生素耐药,其耐药率明显高于ESBLs阴性菌株.结论 革兰氏阴性菌是败血症的主要致病菌,大肠埃希菌是最常见的病原菌.导致败血症的病原菌常存在多重耐药性,产ESBLs是大肠埃希菌耐药的重要原因.应加强对病原菌ESBLs的监测,预防和控制耐药菌株的传播流行.

Spectra and drug resistance of pathogenic bacteria in 520 septicemia patients from Jan.2006 to Dec.2007

Objective To investigate the spectra and their drug resistance of pathogenic bacteria in septicemia patients.Methods The blood samples of inpatients were cultured by blood culture apparatus.The isolated bacteria were identified by VITEK AMS,and their drug resistance tests were conducted by K-B,and ESBLs was detected by disc diffusion confirmatory test.Results Of the 520 samples,107(20.6 %) strains of pathogens were isolated,among which 56(52.3%) were Gram-negative bacteria,40(37.4%) were Gram-positive and 11(10.3%) were fungi.The most common pathogens were Escherichia coli(28,26.2%),Staphylococcus(25,23.4%) and Klebsiella(11,10.3%).Of 28 strains of Escherichia coli,ESBLs were detected in 13 strains(46.4%);and of 11 strains of Klebsiella,the positive rate of ESBLs was 27.3%(3/11).The ESBLs positive pathogens had a higher resistance rate than ESBLs negative pathogens.Conclusions The Gram-negative bacteria were the predominant pathogen of septicemia,and the Escherichia coli were the most common one.The spectra and their drug resistance characteristics of pathogenic bacteria in septicemia should be emphasized,it is important to detect enzyme producing pathogens regularly for reference of reasonable antibiotic use.