医院感染革兰阴性杆菌产AmpC酶状况及耐药性检测分析

Analysis on drug resistance in Gram-negative bacilli producing AmpC enzyme

目的探讨产头孢菌素酶(AmpC酶)革兰阴性杆菌医院内感染现状及对药物敏感性的影响。方法对临床标本进行分离鉴定,采用K-B法对常规药物进行耐药性检测,采用美国国家临床实验室标准化委员会(NCCLS)推荐的三维法检测AmpC酶。结果在331株革兰阴性杆菌中检出产AmpC酶109株,产酶率为18.4%,产酶菌株对第3代头孢菌素、头霉素类、环丙沙星及含酶抑制剂复合物药物敏感率下降明显,对亚胺培南、头孢吡肟、丁胺卡那耐药率较低,分别为3.28%(2/61)、44.26%(27/61)、31.1%(19/61),产酶菌株对抗菌药物的耐药率明显高于非产酶菌株。结论革兰阴性杆菌耐药与产AmpC酶有关,治疗该菌感染应选用亚胺培南、第4代头孢菌素等。

Objective To investigate the nosocomial infection status and drug resistance of Gram-negative bacilli producing cephalosporinase（AmpC enzyme）.Methods Strains producing AmpC lactamases were detected by three-dimensional extract test.Drug susceptibility was determined by K-B disk diffusions method.Results The overall incidence rate of strains positive with AmpC lactamases was 18.4%（109/331）.The susceptibility rate of AmpC enzyme positive strains to third-generation cephalosporins,cephamycins,monobactam and antibiotics combined with inhibitors decreased,and relatively lower to Impenem,Cefepime and Amikacin,with resistace rate of（2/61）,44.26%（27/61） and 31.1%（19/61） respectively.Resistance rates of AmpC enzyme positive strains were obviously greater than those of negative strains.Conclusion Drug resistance of Gram-negative bacilli might be associated with AmpC enzyme.Imipenem and forth-generation cephalosporins could be considered firstly for treatment of infection caused by AmpC enzyme positive Gram-negative bacilli.