Piddock L J, Diver J M, Wise R
Eur J Clin Microbiol. 1986 Aug;5(4):411-5. doi: 10.1007/BF02075696.
One hundred urine isolates Enterobacteriaceae screened for resistance to 30 micrograms nalidixic acid by disc diffusion test were examined by MIC determination for in vitro susceptibility to nalidixic acid, ciprofloxacin, enoxacin, gentamicin, nitrofurantoin, trimethoprim, cephalexin and ceftazidime. Those resistant to nalidixic acid and also gentamicin or a cephalosporin were further examined to determine the mechanism of resistance. Compared to the total urine isolates of Enterobacteriaceae from the same time period, this population as a whole was less susceptible to all antimicrobials tested except gentamicin. Strains that exhibited multiple resistance had the conventional mechanisms of resistance to those antimicrobials. No multiply resistant strains had a permeability barrier due to outer membrane protein alterations causing cross-resistance to chemically unrelated classes of antimicrobials.
通过纸片扩散法筛选出100株对30微克萘啶酸耐药的尿源肠杆菌科细菌，通过最低抑菌浓度（MIC）测定来检测其对萘啶酸、环丙沙星、依诺沙星、庆大霉素、呋喃妥因、甲氧苄啶、头孢氨苄和头孢他啶的体外敏感性。对萘啶酸以及庆大霉素或头孢菌素耐药的菌株进一步检测以确定耐药机制。与同一时期的全部尿源肠杆菌科细菌分离株相比，总体而言，该群体除对庆大霉素外，对所有测试抗菌药物的敏感性均较低。表现出多重耐药的菌株具有对这些抗菌药物的传统耐药机制。没有多重耐药菌株因外膜蛋白改变导致对化学结构不相关的抗菌药物类别产生交叉耐药而具有通透性屏障。
