Study On12β-lactamase Genes And Molecular Epidemiology In38Strains Of Multidrug-resistant Acinetobacter Baumannii

ObjectiveTo investigate the existence of β-lactamase genes and characteristics ofMolecular epidemiology in38strains of multidrug-resistant Acinetobacterbaumannii.MethodsThe antibiotics susceptibility test was performed according to the AmericanCLSI2007standard, and the β-lactamase genes were detected by using PCRassay. And ERIC-PCR typing was used to investigate the epidemiologicalcharacteristics of isolates.Product of positive strain was performed onsequencing.ResultsIt was found that existence of multidrug resistance of Acinetobacterbaumannii was serious under this condition, because in these38strainsisolated were resistant to14different antimicrobial drugs. To the12β-lactamase genes tested, the positive strains to blaTEM, blaADC, blaOXA-23,blaPER-1and blaSHV were33(86.84%),31(81.58%),25(65.79%),5(13.16%),1(2.63%) respectively. Among these strains,5strains were positivefor all these5genetypes,24strains positive for blaTEM,blaADC andblaOXA-23,5strains were positive for both blaTEM and blaADC,1strain positive for both blaTEM and blaSHV,1strain positive for both blaADC andblaOXA-23.38strains of Acinetobacter baumannii were derived from12identical clonal strains,60.53%was A-type, which is highest detected.23strains of Acinetobacter baumannii were A-types,24,25and26wereB-type,30,31and32were C-type, the others had no close relevance.ConclusionsThere are not only various β-lactamase genes, but also higher percentageof β-lactamase gene, such as blaTEM, blaADC and blaOXA-23in Acinetobac-ter baumannii isolated in The First Affiliated of Liaoning Medical University.Plasmid DNA profile of ERIC-PCR show that38Acinetobacter baumanniiisolates have genotype polymorphism as revealed by molecular epidemiologyand there was cloning spread probably in the hospital.