临床分离大肠埃希菌耐药性监测

目的了解临床分离大肠埃希菌的耐药性,为临床合理应用抗菌药物提供实验室依据. 方法采用微量稀释法对1 414例临床分离大肠埃希菌进行药物敏感性测定;超广谱β-内酰胺酶(extended spectrum beta-lactamases, ESBLs)检测用微量稀释法初筛,纸片法做确证试验. 结果大肠埃希菌对18种抗菌药物的药敏结果中,耐药率＞30%的抗菌药物多达10种;其中以氨苄西林、氨苄西林/舒巴坦、头孢噻吩、哌拉西林、环丙沙星、复方新诺明、庆大霉素、妥布霉素的耐药率高达＞50%.亚胺培南耐药率最低(2.1%),其次为哌拉西林/他唑巴坦(5.2%).头孢菌素类耐药率有一定的上升趋势;产ESBLs菌株的发生率为25.5%～39.8%,平均为32.7%;产ESBLs菌株对多种抗菌药物的耐药率显著高于非产ESBLs菌株(P<0.05). 结论临床分离大肠埃希菌对多种抗菌药物的耐药率较高,尤其是产ESBLs菌株的高耐药率及多重耐药性更为明显,临床应加强对大肠埃希菌耐药性的监测并防治耐药菌株的传播流行.

Surveillance of Antimicrobial Resistance in Clinical Isolates of Escherichia coli

OBJECTIVE To investigate the resistance in clinical isolates of Escherichia coli and offer experimental data for reasonable antimicrobial agents. METHODS The microbial sensitivity tests of 1 414 clinical isolates of E. coli were tested by micro dilution method. Extended spectrum beta lactamases(ESBLs) were screened by micro dilution method and confirmed by CAZ+CD2 and CTX+CD3. RESULTS Resistant rates over 30% added up to 10 among the 18 tested antimicrobial agents. Resistant rates of E. coli against ampicillin, ampicillin/sulbactam, cephalothin, piperacillin, ciprofloxacin, trimethoprim sulfamethoxazole, gentamicin, tobramycin, respectively, accounted for more than 50%. The lowest of resistant rates was imipenem(2 1%) and the second was piperacillin/tazobactam (5 2%). Resistant rates of E.coli against cephalosporins tended to increasing. Incidences of ESBLs producing strains were from 25 5% to 39 8%. The average was 32 7%. Resistant rates of ESBLs producing strains were much higher than ESBLs nonproducing strains (P<0 05). CONCLUSIONS Resistant rates of clinical isolates of E. coli were rather high and multidrug resistance, especially in ESBLs producing strains. We should give more attention to the surveillance of antimicrobial resistance of E. coli in clinics and prevent transmission and epidemia of their resistant strains.