Multidrug resistance and abaI- biofilm related gene in clinical isolates of Acinetobacter baumannii

Subject Areas : microbiology

Samer Jaafer Naser ¹ , Bita Behboodian ² , Samaneh Dolat Abadi ³

1 - Ms of Biology, Faculty of Convergent Sciences and Technologies, Research Sciences Branch, Tehran, Iran
2 - Assistant Prof , Department of Biology, Faculty of Basic Sciences, Mashhad Branch, Islamic Azad University of Mashhad, Iran
3 - Associate Prof. Department of Microbiology, Ne.C., Islamic Azad University, Neyshabur, Iran

Received: 2025-03-23 Accepted : 2025-05-03 Published : 2025-06-01

Keywords: Acinetobacter baumannii, Biofilm, abaI, Multidrug resistance, Clinical isolates,

Abstract :

Introduction: Acinetobacter baumannii is one of the main strains with high frequency in hospital infections. The increasing antibiotic resistance is one of the main challenges in dealing with this strain in hospital infections. In this study, multidrug resistance, abaI gene expression, and biofilm formation ability were investigated.

Materials and Methods: 141 clinical samples were collected from a selected hospital in Khorasan Razavi Province, and Acinetobacter baumannii strains were subjected to specific biochemical tests and antibiotic susceptibility testing using the disk diffusion method. The presence of the abaI gene in resistant strains was investigated using the Polymerase Chain Reaction (PCR) method.

Results : The frequency of samples infected with Acinetobacter baumannii was 29.5%, with the highest frequency (26.5%) related to sputum and respiratory secretions. In the evaluation of antibiotic resistance, the strains were 87%, 76%, and 64% sensitive to Levofloxacin, Imipenem, and Cefepim, respectively. The results of the biofilm formation test showed that 70% of the isolates could form biofilm. Also, the presence of the abaI gene in isolates with biofilm was reported to be 17%.

Conclusion: The results of the present study show that female patients account for a greater share of hospital infections. The results of antibiotic resistance showed resistance of over 80% for all antibiotics. The highest resistance rate was observed to cefazolin, cefotaxime, and ceftizoxime, respectively, and the lowest to levofloxacin. These results indicate a very high and worrying level of resistance in these isolates

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