106株铜绿假单胞菌耐药性分析及金属β-内酰胺酶检测

Drug resistance analysis of 106 strains of Pseudomonas aeruginosa and detection of metallo-β-lactamases

目的分析医院铜绿假单胞菌的分布、耐药性及产金属β-内酰胺酶的现状,为临床治疗铜绿假单胞菌感染提供合理用药的实验依据。方法将VITEK-2全自动鉴定仪鉴定出的106株铜绿假单胞菌,采用琼脂纸片扩散(K-B)法进行体外耐药性监测及统计耐药率,同时用双纸片协同试验检测金属β-内酰胺酶的百分率。结果 106株铜绿假单胞菌产金属β-内酰胺酶的22株,占20.8%。金属β-内酰胺酶阳性与阴性的铜绿假单胞菌耐药率相比较,对头孢他啶、头孢吡肟、亚胺培南、头孢哌酮/舒巴坦、哌拉西林、哌拉西林/他唑巴坦、头孢曲松、头孢哌酮的耐药率差异有统计学意义(P<0.05);而对氨曲南、阿米卡星、左氧氟沙星、庆大霉素呈现的耐药率二者差异无统计学意义(P>0.05)。结论产金属β-内酰胺是铜绿假单胞菌对β-内酰胺类抗菌药物耐药的主要机制之一,临床应根据药敏结果及产酶情况综合考虑合理用药,以减少耐药菌株的产生。

Objective To analyze distribution,drug resistance and situation of producing metallo-β-lactamase of hospital Pseudomonas aeruginosa for providing the experimental basis of the rational use of drugs for clinical treatment of Pseudomonas aeruginosa infection.Methods 106 stains of P.aeruginosa were identified by VITEK-2 automatic identification system,and,in vitro drug resistance and statistical resistance rates were tested by K-BETA disk diffusion method,while the double disk synergy assay was used to test the percentage of metallo-β-lactamase.Results In 106 stains of Pseudomonas aeruginosa,22（20.8%）of them produced metallo-β-lactamase.Metallo-β-lactamase positive strains of Pseudomonas aeruginosa had significantly higher drug resistance rates to ceftazidime（CAZ）,cefepime（FEP）,imipenem（IPN）,cefoperazone/Sulbactam（SCF）,piperacillin（PIP）,piperacillin/tazobactam（the PIT）,ceftriaxone（CRO）,cefoperazone（CFP） and than negative strains（P0.05）.There wa no significant difference of drug resistance rates of them to Aztreonam（AZT）,levofloxacin（LVF）,gentamicin（GM）（P0.05）.Conclusion Producing metallo-β-lactamase of Pseudomonas aeruginosa is one of the main mechanism of drug resistance to the enzyme β-lactam antimicrobial agents,it should be rationally use medicines in order to reduce resistance strains generating.