摘要
目的 对耐头孢西丁肠杆菌科细菌AmpC酶和超广谱β-内酰胺酶（ESBLs）进行检测及其耐药性分析，提示其主要耐药机理，指导临床合理用药。方法：采用氯唑西林增效试验测定AmpC酶，采用双纸片确诊试验测定ES-BLs，并采用最小抑菌浓度法（MIC法）检测12种常用抗生素对这些菌株的体外抗菌活性。结果：320株受检菌中共检出高产AmpC酶菌145株，产ESBLs菌160株，阳性率分别为45．3％、50％。单产AmpC酶菌对氨曲南、头孢曲松、哌拉西林、哌拉西林／三唑巴坦均存在不同程度的耐药（45．2％-68．5％），其耐药率明显高于非产酶菌，两者相比有统计学意义（P〈0．05）。而单产AmpC酶菌和非产酶菌对氨苄西林、氨苄西林／舒巴坦、环丙沙星、头孢唑啉的耐药率均较高（57．7％-94．2％）；对阿米卡星、头孢吡肟、亚胺培南、头孢哌酮／舒巴坦的耐药率均较低（0％-34．6％），两者相比无统计学意义（P〉0．05）。结论：耐头孢西丁肠杆菌科细菌中高产AmpC酶的检出率较高，高产PunpC酶细菌多呈多重耐药。临床可采用碳青霉烯类抗生素或4代头孢菌素作为高产AmpC酶菌感染的经验治疗，也可根据药敏试验选用头孢哌酮／舒巴坦或阿米卡星等抗生素治疗。
Objective： To detect AmpCβ-lactamases and production of ESBLs in cefoxitin-resistant gram-negative bacilli, and to analyse their resistances. And to reveal the mechanism of it, which will help us medicating reasonably in clinic. Methods： Cloxacillin-potentiated disk diffusion test was use to detect AmpCβ-1actamases, two disk confirming test was used to detect ESBLs, and their antibacterial activities in vitro of 12 antibiotics were analyzed by the minimal inhibitory concentration method. Results： There were 145 strains out of 320 strains isolated producing AmpCβ-1actamases, 160 strains out of 320 strains of isolates produced ESBLs. The positive rate was 45.3% and 50% respectively. The resistant rates of AmpC-positve strains to aztreonam, ceftriaxone, piperacillin and piperacillin/tazobactam were 45.2% - 68.5%, but the resistant rates of enzyme-negative strains were all lower. There was significant difference between the two groups （ P 〈 0.05 ）. The resistant rates of AmpC-positve strains and enzyme-negative strains to ampicillin, ampicillin/sulbactam, ciprofloxacin,cefazolin were all higher（57.7% - 94.2% ）,but the resistant rates to amikacin,cefepime,imipenem and cefoperazone/sulbactam were all lower（0% - 34.6% ） . There was no significant difference between the two groups （ P 〉 0.05）. Conclusion： The incidence of AmpC-producing strains in cefoxitin-resistant gram-negative bacilli was comparatively high, most of AmpC-positve strains had multi-drug resistances. We could choose imipenem or cefepime as clinical experiential treatment to infections caused by AmpC-positve strains. We could also choose cefoperazone/sulbactam or amikacin according to drug susceptibility testing.
出处
《江苏大学学报（医学版）》
CAS
2007年第1期76-78,共3页
Journal of Jiangsu University：Medicine Edition
关键词
AMPC酶
氯唑西林增效试验
耐药性分析
AmpC β-1actamases
cloxacillin-potentiated disk diffusion test
drug resistance analysis
