产超广谱β-内酰胺酶AmpC细菌感染及耐药特性

Produing extended-spectrum β-lactamases and AmpCβ-lactamases strains: detection infection and resistance

关键词:  AmpC  ESBLs  G-菌  耐药性

Key words:  AmpCβ-lactamases  ESBLs  Gram-negative bacteria  drug resistance

摘要:

［目的］了解医院内产超广谱β-内酰胺酶（ESBLs）和高产AmpC细菌感染和耐药特性。 ［方法］ 三维试验检测高产AmpC细菌、双纸片协同试验检测产ESBLs菌。Kirby-Bauer法测定药物敏感试验，回顾患者临床资料及使用抗生素 情况。［结果］ 高产AmpC细菌在阴沟肠杆菌、肺炎克雷伯菌和大肠埃希菌分别为12.8%（11/89）4.1%（7/170）和2.6% （5/190）；产ESBLs 菌分别为42.7%(38/89)，肺炎克雷伯菌31.7%(54/170)，大肠埃希菌27.3%(52/190)，其中同时产两种酶为6株。高产AmpC和产ESBLs菌对三代头孢菌素，氨曲南的耐药性明显高于非产酶菌，对泰能均敏感。前者对四代头孢敏感但对酶抑制剂耐药。高产AmpC和产ESBLs菌感染与使用三代头孢有关。［结论］ 高产AmpC和产ESBLs是临床G-菌耐药的重要机制，其产生与使用三代头孢有关。

Abstract:

［Objective］ To investigate the infecting cause and antibiotic resistanceof producing extended-spectrum β-lactamases (ESBLs)and AmpCβ-lactamases bacteria in hospital. ［Methods］Producing ESBLs bacteria and AmpCβ-lactamases bacteria were detected by double-disk synergy and three-dimensional tests respectively. The antibiotic Susceptibility test was assayed by Kirby-Bauer. ［Results］ The incidence of AmpC- lactamases in E. Colacae. K.pneumoniae and E.coli was 12.8%(11/89),4.1 %(7/170) and 2.6%(5/190)respectively. The incidence of ESBLs in of E. Colacae. K.pneumoniae and E.coli was 42.7%(38/89),31.7 %(54/170) and 27.3%(52/190) respectively.AmpCβ-lactamases combined with ESBLs producing strains were found in 6 strains. Most producing ESBLs bacteria came from the patients treated with the third-generation cephalosporins. The resistance for cephalosporins and Aztreonarn in producing ESBLs and AmpCβ-lactamases strains was significantly higher than that of no producing ESBLs. The infection caused by producing ESBLs bacteria was sturbborn and ready to relapse.［Conclusion］ The production of ESBLs,AmpCβ-lactamases strains were related with using the third-generation cephalosporins. And they lay the sasis of critical mechanism of Gram -negative bacteria，s drug -resistance.