Drug-Resistance of Multi-resistant Pseudomonas aeruginosa

OBJECTIVE To study the mechanism of drug-resistance of multi-resistant Pseudomonas aeruginosa,and provide the guideline for treatment and control of P.aeruginosa infection in hospital.METHODS Fifty strains of multi-resistant P.aeruginosa were selected with K-B susceptibility method.The three-dimensional method was taken to differentiate the various beta-lactamases.The relative drug-resistance gene was detected by polymerase chain reaction(PCR).RESULTS Among 50 strains of multi-resistant P.aeruginosa,there were 2 strains(4%)producing ESBLs,20 strains(40%)producing AmpC beta-lactamases,and 11 strains(22%) producing ESBLs and AmpC beta-lactamases at the same time.There were 8 positive genes in the detected drug-resistance gene,the most common sources of gene were CTX(56%),OprD(60%) and aac(6′)-Ⅱ(60%),respectively.CONCLUSIONS The main beta-lactamases are AmpC beta-lactamases and the main genotype is CTX in the multi-resistant P.aeruginosa cultured in our area.The main course of imipenem-resistance was deletion of outer membrane proteins,and the aminoglycoside modifying enzyme gene and disinfectant-resistance gene in multi-resistant P.aeruginosa are acquired.In order to reduce the drug-resistance strains and control the infection of P.aeruginosa,antibiotics should be used reasonably according to drug susceptibility testing clinically.