Isolation and Antimicrobial Susceptibility of Imipenem-susceptible Pseudomonas aeruginosa

Objective To study the isolation and antimicrobial susceptibility of imipenem-susceptible Pseudomonas aeruginosa in the Second Xiangya Hospital of Central South University.Methods The cultured bacteria were identified with routine methods or MicroScan WalkAway 96 system.The susceptibilities of the bacteria were detected by disk diffusion method and the results were confirmed with the rules of NCCLS/CLSI.The inducible enzymes were tested with imipenem-inducible assay.Results Among the 200 strains of imipenem-susceptible Pseudomonas aeruginosa,70.5% came from sputum or throat swabs,and 22.5% came from pus or secretion.The proportion of these strains from respiratory department was 19.5%,from geriatric department 19.0% and from orthopaedics department only 13.5%.The susceptibility rates of strains for meropenem,ceftazidime,amikacin,and piperacillin/tazobactam were 94.0%,87.5%,86.5%,and 80.5%,respectively.The intermediate rate for cefoperazone/sulbactam and aztreonam was 20.0% and 17.0%.The rate of strains producing inducible enzymes was 27.5%.Conclusions The strains of imipenem-susceptible Pseudomonas aeruginosa mainly come from respiratory tract infections and wound infections,and the susceptibility for most antibiotics is high.As a kind of strong derivant,imipenem can make Pseudomonas aeruginosa induce resistance.