耐亚胺培南铜绿假单胞菌产金属β-内酰胺酶的研究

Analysis of metallo-beta-lactamase producing of strains resistant to imipipenem in pseudomonas aeruginosa

目的检测该院2005年4～7月住院患者耐亚胺培南铜绿假单胞菌（PA）产金属β-内酰胺酶（MBL）的情况，为难治性感染治疗提供参考。方法VITEK-60鉴定细菌及测定PA对抗菌药物的耐药性；纸片法检测PA产MBL。结果共检出PA103株，耐亚胺培南PA47株，同时耐头孢他啶16株，其中产MBL的PA8株，占所分离PA的7．8％，占耐亚胺培南PA的17．0％。8株产酶菌株中除1株对左旋氧氟沙星敏感外，对羧苄青霉素、阿米卡星、替卡西林／克拉维酸、头孢哌酮、头孢他啶、头孢吡肟、奈替米星、复方增效磺胺、哌拉西林／他唑巴坦、环丙沙星等抗生素均耐药；非产酶菌株仅有2株对羧苄青霉素敏感，1株对阿米卡星敏感，对其他抗生素均耐药。结论临床感染分离的PA、产酶菌株与非产酶菌株均呈多重耐药性。产MBL是PA对头孢类及碳青酶烯类抗生素耐药的机制之一，实验室对其正确检测可帮助临床合理选用抗菌药物，并减少耐药性的扩散。

Objective To detect the situation of metallo-beta-lactamase（MBL） producing of strains resistant to imipenem in pseudomonas aeruginosa（PA） isolated from hospital patients from April to July in 2005. Methods PA strains were isolated and antimicrobial resistances were done by the VITEK auto microbic system. MBL producing strains were detected by Kirby bauer method. Results 103 strains of PA were isolated. There were 47 strains resistant to imipenem and 16 strains resistant to ceftazidime. 8 strains were found MBL producing. Accounted for 17.0% of resistance strains to imipenem. One of 8 strains was sensitive to levofloxacin,others were resistant to such antibiotics as carbenicillin, amikacin, ticarcillin/clavulanic acid, eefoperazone, ceftazidime, cefepime, netilmicin,trimethoprim/sulfamethoxazole, piperacillin/tazobactam, ciprofloxacin. Non-MBL producing strains were found resistant to almost all antibiotics, except that 2 strains were sensitive to carbenicillin and one was sensitive to amikacin. Conclusion Among the PA strains isolated from clinic, both MBL producing strains and non-MBL ones were multiple antimicrobial resistance. It was one of the antimicrobial merchanisms that MBL producing led to PA resistant to cephalosporins and carbapenems. Antimicrobial agents should be chosen reasonably under the help of laboratory detecting this type correctly so as to reduce the antimicrobial resistance.