Drug resistance of AmpC enzyme-producing acinetobacter baumannii and distribution of ampC genes in Xi′an

OBJECTIVE To investigate the status of the drug resistance and the distribution of the ampC gene,the detection of the AmpC enzyme in 146 strains of Acinetobacter baummannii.METHODS Microscan walkaway-4.0 was used to detect the susceptibility of antimicrobial agents against 146 clinical strains.AmpC gene was amplified by polymerase chain reaction(PCR).AmpC enzyme was examined by Cefoxitin in three dimensional test.RESULTS Among the 146 strains,ampC genes were found in 93 strains by PCR with the positive rate of 63.7%.65 strains had produced AmpC enzyme with the enzyme production rate of 44.5%.The sensitivity rates of 146 strains to IPM,LEV,AMK,FEP,TOB,SCF,GEN,CIP,TZP,CAZ,TIM,SXT,PI,ATM,CTX and CRO were 89.7%,75.3%,62.3%,59.6%,58.9%,48.6%,43.8%,22.6%,15.1%,15.1%,13.7%,11.6%,11.0%,3.4%,2.7% and 2.7%,respectively.CONCLUSION The drug resistance of A.baummannii is severe in Xi′an.To make clear about the highly productive AmpC enzyme strains is helpful for the clinical selection of antibiotics.