肺结核并发粘质沙雷菌肺部感染的耐药性分析及产ESBLs、AmpC酶和碳青霉烯酶的检测

Drug resistance of pulmonary tuberculosis complicated with lung infection by Serratia marcescens and detection of ESBLs,AmpC enzyme and carbapenemases

目的探讨肺结核患者并发粘质沙雷菌肺部感染的耐药现状及ESBLs、AmpC酶、碳青霉烯酶的检测率,指导临床合理使用抗菌药物。方法收集2011年1月至2015年6月从缙云县人民医院肺结核并发粘质沙雷菌肺部感染患者的痰液标本中分离的74株粘质沙雷菌,K-B纸片法进行药敏试验,采用双纸片确证试验进行ESBLs检测、头孢西丁三维试验法检测AmpC酶、改良Hodge试验筛选碳青霉烯酶,利用WHONET 5.6软件分析药敏试验数据。结果药敏试验表明粘质沙雷菌对氨苄西林、头孢唑林、头孢呋辛、氨曲南的耐药率较高,耐药率均大于60.0%,对妥布霉素、亚胺培南、美罗培南、阿米卡星、丁胺卡那霉素的耐药率较低,耐药率均小于10.0%;在74株粘质沙雷菌中,共有21株产ESBLs,检出率为28.4%;产AmpC酶15株,检出率为20.3%,同时产ESBLs和AmpC酶细菌6株,占8.1%;对美罗培南耐药的菌株5株,改良Hodge试验阳性株4株,阳性率为5.4%。结论从肺结核患者分离出的粘质沙雷菌多重耐药率高,耐药机制复杂,耐药性的产生与产ESBLs、AmpC酶、碳青霉烯酶有关,临床应根据药敏试验结果合理用药。

Objective To study the drug resistance of tuberculosis complicated with pulmonary infection by Serratia marcescens and the detection rates of ESBLs,AmpC enzyme and carbapenemases,in order to provide evidences for clinical rational use of antibacterial drugs.Methods 74 strains of Serratia marcescens isolated from the sputum specimens of pulmonary tuberculosis patients with Serratia marcescens infection from January 2011 to June 2015 were collected;their drug sensitivity were tested by using K-B method.ESBLs were detected by using double disk test.AmpC enzyme was detected with cefoxitin three-dimensional test.carbapenemases were screened with modified Hodge test.The data of drug sensitivity test were analyzed by using WHONET 5.6software.Results The resistance rates of Serratia marcescens to ampicillin,cefazolin,cefuroxime and aztreonam were over 60.0%,while those to tobramycin,imipenem,meropenem and amikacin were less than 10.0%.21 strains were ESBLs producers（28.4%）,15 were AmpC enzyme producers（20.3%）,while 6strains were producers of both ESBLs and AmpC enzymes（8.1%）.5strains were resistant to meropenem.4strains were positive to modified Hodge test（5.4%）.Conclusion The multi drug resistance rate of Serratia marcescens isolated from patients with pulmonary tuberculosis were high and the mechanism of the resistance was complicated.The drug resistance is related to ESBLs、AmpC enzyme and carbapenemases.antibacterial drugs should be used reasonably based on the results of drug sensitivity test.