头孢菌素折点变化对大肠埃希菌和肺炎克雷伯菌药物敏感性及产超广谱β内酰胺酶菌株分布的影响  

Influence of change of cephalosporin breakpoints on susceptibility interpretation on Escherichia coli,Klebsiella pneumonia and distribution of ESBLs-producing bacteria

作　　者：黄秋兰 侯惠丽 范德平 

机构地区：[1]上海市嘉定区南翔医院检验科,上海201802

出　　处：《诊断学理论与实践》2013年第2期221-223,共3页Journal of Diagnostics Concepts & Practice

基　　金：上海市嘉定区卫生局科研基金项目(KYXM 2009-12-8)

摘　　要：目的:评估美国临床与实验室标准化协会(CLSI)M100-S20(S20)文件中,有关头孢噻肟(CTX)、头孢曲松(CRO)、头孢他啶(CAZ)和头孢唑肟(ZOX)折点变化,对本地区大肠埃希菌、肺炎克雷伯菌体外药物敏感性及产超广谱β内酰胺酶(ESBLs)菌株分布的影响。方法:采用纸片扩散法,对2010年至2011年间分离到的306株大肠埃希菌、肺炎克雷伯菌,进行CTX、CRO、CAZ和ZOX的体外药物敏感性试验,用WHONET 5.4软件根据CLSI这2种折点标准(S19、S20)进行判读,CLSI表型确证试验确认产ESBLs菌株。结果:在S19下,大肠埃希菌、肺炎克雷伯菌对CTX的耐药率分别是66.3%、43.8%;在S20下,大肠埃希菌、肺炎克雷伯菌对CTX的耐药率分别是68.1%、45.5%,CRO与CTX相似。但在S19下,大肠埃希菌、肺炎克雷伯菌对CAZ的耐药率分别为31.4%、22.3%;而在S20下,大肠埃希菌、肺炎克雷伯菌对CAZ的耐药率分别上升至43.2%、34.7%,ZOX与CAZ相似。大肠埃希菌、肺炎克雷伯菌中,产ESBLs菌的阳性率分别是62.7%和40.5%。产ESBLs的大肠埃希菌、肺炎克雷伯菌对CTX的耐药率分别由S19折点下的93.1%、91.8%上升为新折点下的98.3%、98.0%,敏感率则由S19折点下4.3%、4.1%下降至新折点下的0.0%、0.0%。CRO的结果和CTX近似,新折点与ESBLs表型分布具有良好的对应关系,而CAZ的耐药率分别由S19折点下的33.6%、40.8%上升为新折点下的44.0%、57.1%,敏感率则由S19折点下56.0%、42.9%下降至新折点下的41.4%、26.5%,ZOX结果与CAZ相似,新旧折点标准下药敏结果分布率的差异有统计学意义(P<0.01)。结论:应用新折点,CTX和CRO药敏结果与ESBLs表型检测结果具有高度一致性,临床医师可根据药敏结果选择用药;对于ZOX和CAZ,虽然新折点提高了大肠埃希菌、肺炎克雷伯菌的耐药表型与产ESBLs检出率的一致性,但与临床治疗结局的相关性还有待进一步评估。Objective To evaluate the influence of change of cephalosporin breakpoints in CLSI M100-S20 on susceptibility interpretation and distribution of ESBLs-producing bacteria of Escherichia coli, Klebsiella pneumonia to cefotaxime, ceftriaxone, ccftazidime and Ceftizoxime. Methods A total of 306 clinical isolates were collected from patients in Jiading Nanxiang Hospital from 2010 to 2011. Antimicrobial susceptibility was detected by disk diffusion method. WHONET 5.4 software was used to analyze the data according to S19 and S20, respectively. ESBLs production was confirmed by the CLSI phenotypic confirmatory test. Results As to Escherichia coli and Klebsiella pneumonia, the resistant rates of cefotaxime increased from 66.3%, 43.8% under S19 to 68.1%, 44.5% under S20. Ceftriaxone had the same trend as cefotaxime. As to Escherichia coli and Klebsiella pneumonia, the resistant rates of ceftazidime increased from 31.4%, 22.3% under S19 to 43.2%, 34.7% under S20. Ceftizoxime had the same trend as ceftazidime. ESBLs producers were detected in 62.7% of Escherichia coli and 40.5% of Klebsiella pneumonia. As to the ESBL positive Escherichia coll and Klebsiellapneumonia, the resistant rates of cefotaxime increased from 93.1%, 91.8% under S19 to 98.3%, 98.0% under S20. The susceptibility rates decreased from 4.3%, 4.1% to 0.0%, 0.0%. Ceftriaxone had the same trend as cefotaxime. New breakpoints had a good correspondence with the ESBLs phenotype, but the resistant rates of ceftazidime increased from 33.6%, 40.8% under S19 to 44.0%, 57.1% under S20. The susceptibility rates decreased from 56.0%, 42.9% to 41.4%,26.5%. Ceftizoxime had the same trend as cefotaxime. There was a significant difference between the S19 and S20 in distribution of ESBLs producers （P〈0.01）. Conclutions Application of new cefotaxime, ceftriaxone S20 breakpoints would increase the concordance of bacterial susceptibility results and ESBLs phenotype for selecting the proper antibiotics according to the results of bacterial susceptibility. As to ceftazidim

关 键 词：大肠埃希菌 克雷伯菌 头孢菌素类 Β内酰胺酶类 药物敏感性 折点 

分 类 号：R446.5[医药卫生—诊断学]