Biofilm-Associated Genes and Antibiotic Susceptibility in Burn-Isolated Pseudomonas aeruginosa

ORIGINAL ARTICLE
Fatimah A. Abdul Jabbar, Mustafa S. Al-Salmani, Hadeer R. Kamel, Hasan A. Aal Owaif

 
For citation: Jabbar FAA, Al-Salmani MS, Kamel HR, Aal Owaif HA. Biofilm-Associated Genes and Antibiotic Susceptibility in Burn-Isolated Pseudomonas aeruginosa. International Journal of Biomedicine. 2025;15(4):727-730. doi:10.21103/Article15(4)_OA13
 
Originally published December 5, 2025

Abstract: 

Background: Burn injuries reduce skin protection and immune responses, making them a global health issue. Among the most prevalent opportunistic bacteria in burn wounds is Pseudomonas aeruginosa, which is drug-resistant and produces biofilms. This study investigated biofilm-associated virulence genes, antibiotic susceptibility, and the link between gene expression, biofilm production, and antibiotic resistance.
Methods and Results: Burn patients hospitalized in Baghdad between June and August 2024 provided 120 burn swabs.  P. aeruginosa isolates were identified using biochemical tests and the VITEK-2 system. Susceptibility to antibiotics was determined using the Kirby-Bauer disk diffusion technique and interpreted in accordance with the 2024 CLSI criteria. A microtiter plate test was used to quantify the production of biofilm at an optical density (OD) of 570 nm. The algD, pelA, and pslA genes were detected by PCR.
P. aeruginosa has been verified in 57 (47.5%) of the isolates. Of them, 91.2% were resistant to ceftazidime, 87.7% to imipenem, 73.7% to gentamicin, and 61.4% to ciprofloxacin. MDR was detected in 63.1% of isolates. In 49.1%, 35%, and 15.9% of the isolates, biofilm development was strong, moderate, and weak, respectively. The algD, pelA, and pslA genes were detected in 86.0%, 68.4%, and 59.6% of the isolates, respectively. A clear relationship was observed between these genes and biofilm production and resistance patterns.
Conclusion: The results in our study support a robust link between biofilm production, antibiotic resistance, and genes related to biofilm production by P. aeruginosa isolated from burn sites. Implementing gene-targeted techniques and optimal combination treatment may greatly enhance infection management and patient outcomes in burn care facilities.

Keywords: 
Pseudomonas aeruginosa • burn infections • antibiotic susceptibility • biofilm production • virulence genes
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Received September 23, 2025.
Accepted November 13, 2025.
©2025 International Medical Research and Development Corporation.