Resistance and ?-Lactamases of Acinetobacter baumannii / 中华医院感染学杂志

ABSTRACT

OBJECTIVE To investigate the relationship of resistance and ?-lactamases of Acinetobacter baumannii.METHODS The bacteria cultured were identified with API 20NE system.The susceptibilities of the bacteria were detected by disk diffusion method.The ?-lactamases produced by these strains were characterized by three-dimensional test and 2-mercaptopropionic acid inhibition assays.RESULTS In 150 strains,the resistant rates of strains were 4.0% to cefoperazone/sulbactam.The resistant rates to imipenem,meropenem,piperacillin/tazobactam,ampicillin/sulbactam and levofloxacin were between 20.0% and 55.0%.The resistant rates to ceftazidime,cefepime,aztreonam and amikacin were above 60.0%.Three-dimensional test showed that 37 strains(24.7%) produced extended spectrum ?-lactamases(ESBLs),66 strains(44.0%)produced AmpC enzymes and 16 strains(10.7%)produced carbapenemases,in which 12 strains(8.0%) produced metallo-?-lactamases.CONCLUSIONS The resistant rates of A.baumannii to routine antibiotics are high except cefoperazone/sulbactam and carbapenem.It is the most important reason for multi-drug resistance that the strains of A.baumannii produce ESBLs,AmpC enzymes and metallo-?-lactamases.