Correlation Between Drug Resistance And Virulence Genes Of Carbapenem Resistant Acinetobacter Baumannii

ObjectiveThe correlation was to investigate between carbapenem-resistant Acinetobacter baumannii resistance and virulence genes in 173 non-duplicated Acinetobacter baumannii strains collected from the First Affiliated Hospital of Anhui Medical University from November 2018 to November 2019.The homology characteristics of carbapenem-resistant Acinetobacter baumannii with the same ST type from blood borne infection and respiratory tract infection were collected for analysis.Method173 non repetitive strains of Acinetobacter baumannii were collected from the First Affiliated Hospital of Anhui Medical University from November 2018 to November2019.The API identification strip of bio Merieux company was used for determination.The 173 strains of Acinetobacter baumannii were selected with imipenem or meropenem,and the minimal inhibitory concentration(MIC)of Acinetobacter baumannii was greater than 8 μ g / ml.Then the remaining strains were detected by K-B method Further screening,the bacteria with imipenem inhibition diameter less than or equal to 14 mm or meropenem inhibition circle diameter less than or equal to19 mm were selected to analyze the resistance of these bacteria to carbapenems.The resistance related genes(blaoxa-23,blaoxa-51,blakpc,blaoxa-24,blaimp,blaoxa-58,blavim,blasim)and virulence genes(cuse,BAP,Abai and bfms)were detected by PCR amplification.Objective to analyze the relationship between drug resistance and virulence genes of Acinetobacter baumannii.The homology analysis of carbapenem Acinetobacter baumannii isolated from the same ST was carried out by using the method of pulsed field gel electrophoresis(PFGE).The virulence effect of Acinetobacter baumannii infected by Bauman Acinetobacter species was tested by using the pulsed field gel electrophoresis(PFGE).Results1.Among the 173 strains of Acinetobacter baumannii collected,only 84 strains met the experimental requirements.The remaining strains were labeled and stored in-80 ℃ refrigerator.2.After screening,84 carbapenem resistant Acinetobacter baumannii strains were resistant to piperacillin,imipenem,ceftazidime,meropenem,cefepime,compound sulfamethoxazole,cefotaxime,gatifloxacin,ceftriaxone,gentamicin,tigecycline,amikacin,minocycline,ciprofloxacin and levofloxacin,and the drug resistance rates were 95.23%,100.00% respectively 94.04%、100.00%、94.04%、97.61%、96.42%、79.76%、95.23%、95.23%、0.00%、84.52%、57.14%、96.42%、76.19%。3.76 strains with drug resistance gene BLAOXA-23 were detected;84 strains with drug resistance gene Blaoxa-51;There were 77 strains of CUSE with virulence gene.There were 74 strains with virulence gene BAP and 80 strains with virulence gene ABAI.There were 76 strains of BFMS with virulence gene.No genes of BLAKPC,BLAOXA-24,BLAIMP,BLAOXA-58,BLAVIM and BLAASim were detected.4.The drug resistance rate of 84 strains of Acinetobacter baumannii with virulence genes ABAI and BFMS was significantly higher,and the drug resistance of Acinetobacter baumannii with virulence genes ABAI and BFMS was significantly different from that of Acinetobacter baumannii without ABAI and BFMS(P<0.05).5.The electrophoresis patterns of the two carbapenem-resistant Acinetobacter baumannii strains with the same ST typing and derived from blood and sputum respectively were identical.6.The survival rate of larvae infected with carbapenem-resistant Acinetobacter baumannii decreased significantly.Conclusion Acinetobacter baumannii in our hospital has serious resistance to carbapenem antibiotics,mainly carrying Blaoxa-23 and Blaoxa-51 resistance genes.Drug resistance is closely related to virulence genes ABAI and BFMS.Pulsed field gel electrophoresis of two carbapenem-resistant Acinetobacter baumannii strains with the same ST typing.The survival rate of larvae infected with carbapenem-resistant Acinetobacter baumannii decreased significantly.