Phenotypic and molecular detection of AmpC-beta-lactamase in Acintobacter baumannii strains isolated of clinical specimens

Subject Areas : microbiology

Masoumeh  Ali Barari ¹ (Department of Microbiology, Biological Science College, Varamin-pishva branch, Islamic Azad University,Varamin-Pishva,Iran)
Fatemeh  Noorbakhsh ² (Department of Microbiology, Biological Science College, Varamin-pishva branch,Islamic Azad University,Varamin-Pishva,Iran)
Sahar  Honarmand Jahromi ³ (Department of Microbiology, Biological Science College, Varamin-pishva branch, Islamic Azad University,Varamin-Pishva,Iran)

Received: 2021-11-10 Accepted : 2021-12-29 Published : 2021-08-23

Keywords: "Acinetobacter baumannii", "AmpC Betalactamase", "Combined Disk test",

Abstract :

Background and aim: Acinetobacter baumannii is an opportunistic pathogen that remains persistent in the environment for a long time. The eradication of this bacteria is difficult, since it has the ability to acquire antibiotic resistance. The aims of this study were to identify the ampC Betalactamas genes and antibiotic sensitivity of Acinetobacter baumannii strains.Materials and methods: Sixty three strains of Acinetobacter baumannii isolates from wound, blood, and respiratory secretions were isolated and identified by biochemical tests. Antimicrobial susceptibility testing against five antibiotics was performed by disc diffusion method for all isolates. Phenotypic methods combined disc test (CDT), was performed for idenfication AmpC Betalactamase activity in bacteria. The presence of AmpC Betalactamase and ISAba-1 and ISAba-2 genes were evaluated by PCR. Results: Disk difiusion result showed that all of samples were resistance to 5 antibiotics ceftriaxone, cefoxitin, ceftazidime, cefotaxime and cefepime. Combined Disk test result showed that (63%) of samples were strong (30%) weak and (6%) of negative. AmpC betalactamase gene in 90.5% were positive and in 9.5% were negative. All of sampls had ISAba-1 gene (69.2%) had ISAba-2. Conclusion: Current study showed a high percentage of AmpC Betalactamas genes and also high prevalence of antibiotic resistance in Acinetobacter baumannii