鲍氏不动杆菌产AmpC酶的检测与耐药性分析

Detection and Resistance of AmpC β-Lactamases Producing Acinetobacter baumannii

目的探讨鲍氏不动杆菌AmpC酶初筛及确证检测意义,了解医院鲍氏不动杆菌产AmpC酶的情况。方法对分离出的细菌采用BD Phoenix100全自动细菌鉴定系统进行鉴定,分别用头孢西丁三相试验进行产AmpC酶初筛试验,三维试验进行产AmpC酶确证试验,并对两者进行比较,药敏试验采用K-B法。结果在62株作AmpC酶检测鲍氏不动杆菌中,头孢西丁三相试验和三维试验两种方法检出率为38.7%和25.8%;与三维试验比较,头孢西丁三相试验敏感度为87.5%,准确度为80.6%,特异度为78.3%,AmpC酶阳性株均呈多药耐药,其对多种抗菌药物的耐药率明显高于AmpC酶阴性株。结论临床实验室对鲍氏不动杆菌建立AmpC酶检测初筛制度,对控制鲍氏不动杆菌多耐药株出现具有积极意义。

OBJECTIVE To study the screening method and significance of detecting AmpC β-lactamases produced by Acinetobacter baumannii and understand the prevalence in hospital.METHODS The isolated bacteria were identified by BD phoenix 100 automatic system.Cefoxitin three-dimension was used for screening AmpC β-lactamases from A.baumannii and three-dimensional test was applied to affirm them respectively.Then a comparison was made between them.K-B method was adopted in the drug-sensitivity test.RESULTS Among 62 strains of A.baumannii,the detection rates by cefoxitin three-dimension and three-dimensional test were 38.7% and 25.8%,respectively.Comparing with three-dimensional test,the sensitivity of cefoxitin three-dimension was 87.5%,with accuracy rate 80.6% and specificity 78.3%.The positive strains of AmpC β-lactamases were multi-resistant.Their resistance rate to several antibiotics was apparently higher than the negative strains of AmpC β-lactamases.CONCLUSION The system of detecting and screening AmpC β-lactamases established by the clinical laboratory is significant to control the appearance of multi-antibiotic resistant strains in A.baumannii.