Study on AmpC beta-lactamase and ESBLs in pseudomonas aeruginosa

Objective:To study the phenotype and genic type of AmpC beta-lactamase and ESBLs in pseudomonas aeruginosa.Methods:K-B disc method was used to detect ESBLs.AmpC beta-lactamase was detected on the basis that AmpC beta-lactamase could be inhibited by 3-aminophenylbooronic acid（APB）.Imipenem and multisubstrates were used to detect the inducible AmpC β-lactamase,PCR was used to detect genes of AmpC and ESBLs,and DNA sequencing was adopted to analyze genes.Results: 1 strain and 51 strains showed ESBLs and AmpC positive phenotype.Among them,the specific band of AmpC（dha,1 strain） and ESBLs（tem,1 strain） were detected.The sequence result was DHA-1.From the 51 AmpC positive strains of P.aeruginosa,33 strains produced the inducible AmpC β-lactamase.The inducible rates were aztreonam,ceftazidime-clavulanate＞piperacillin＞cefepime ＞ceftazidime＞cefotaxime＞cefotaxime-clavulanate.Conclusion: There are multidrug resistant P.aeruginosa strains in PLA general hospital.