Study on the resistant mechanism of Acinetobacter Baumannii related with integrons

Objective: To investigate the resistant mechanism of Acinetobacter baumannii and the distribution of integrons in Acinetobacter baumannii.Methods: Non-repetitive 54 clinical strains of A.baumannii were collected from the specimens of inpatient of the First Affiliated Hospital.The antimicirobial susceptibility was determined with K-B method and the integrons gene was amplified with PCR,the positive PCR products were sequenced to confirm the cassettes type and arrangement.Results: The susceptibility test demonstrated that the rate of resistance to monobactam,cephalosporins,aminoglycosides and fluoroquinolone were varied from 85% to 99%,nitrofurans had the lowest resistant rate,17%.The PCR results showed that 40 clinical strains had integron genome,the length of the products mainly were 2 200 bp.The sequencing results indicated that most of the type I integrons carried the aminoglycoside acetyltransferase genome and the aminoglycoside adenyltransferase genome,the insert sequence and the metal-β-lactamase genome were also detected in parts of these strains.Conclusions: Most of the prevalent strains of A.baumannii carry the type I integrons,the new evolutional mode of resistant mechanism developes in these strains.