Study on in vitro resistance of cefoperazone/sulbactam against Acinetobacter baumannii

OBJECTIVE To investigate the drug resistance of Acinetobacter baumannii and to evaluate the characteristic of resistance against cefoperazone/sulbactam.METHODS Retrospective survey was used to study the distribution of A.baumannii in our hospital from Jan.2007 to May.2011;VITEK-60 AMS was used to detect the susceptibility of A.baumannii against ciprofloxacin,ceftriaxone,ceftazidime,gentamicin,tobramycin,SMZ-TMP,ampicillin/sulbactam,piperacillin/tazobactam and imipenem.Agar dilution method was used to detect the minimum inhibitory concentration(MIC) of cefoperazone/sulbactam.RESULTS A total of 603 strains of A.baumannii were isolated from respiratory tract,accounting for 90.4% and the most risky area was intensive care unit(70.3%).The resistance rate of A.baumannii exceeded 60.0% against clinical frequently used antibiotics except for cefoperazone/sulbactam.The ratio of intermediate exceed 50.0% in cefoperazone/sulbactam un-resistant strains.CONCLUSION A.baumannii tends to distribute in some common sites and comes from the same sources,The drug resistance of A.baumannii is high.The MIC is increasing of strains un-resistant to cefoperazone/sulbactam.