Detection of The Psla And Pela Genes in Multidrug-Resistant Pseudomonas Aeruginosa Isolated from Respiratory Infections

Abstract

Background: Pseudomonas aeruginosa is a leading opportunistic pathogen that have the ability to produce biofilms using secreted extracellular polymeric substances are typically controlled by the pslA and pelA genes. The current study was undertaken to determine the prevalence of pslA and pelA genes in MDR P. aeruginosa isolated from respiratory infections, and to assess its correlation with antibiotic resistance profile.

Methods: Cross-sectional study carried in Hilla Teaching Hospital, Babylon Province-Iraq during the period from July 2024 to January 2025. Methods: 87 patients who presented with clinically suspected respiratory tract infections. Antimicrobial susceptibility tests were conducted using the Kirby–Bauer disk diffusion method according to CLSI guidelines as follows: ceftazidime, imipenem, meropenem, ciprofloxacin, levofloxacin, gentamicin and amikacin. Molecular Detection of pslA and pelA GenesMultidrug-resistant isolates were selected to be used for the molecular detectionof the pslA genes by conventional PCR.

Results: Ciprofloxacin (85.0%) and levofloxacin (82.5%) had the highest resistance rates, followed by ceftazidime (77.5%), meropenem (75.0%), and imipenem (70.0%); however, amikacin had the lowest resistance rate at 45%. In molecular analysis, the pslA gene was identified in 95.0% of MDR isolates and pelA gene was found in 87.5%. The presence of pslA and pelA genes is significantly associated with resistance to β-lactams, carbapenems and fluoroquinolones (p < 0.05; however, aminoglycosides showed no significant correlation.

Conclusion: The Pseudomonas aeruginosa Respiratory Isolates of Multidrug Resistant Bacteria (MDR) exhibited high frequency of pslA and pelA genes which imply that biofilm formation took a major part in bacterial persistence and MDR. The major correlation with biofilm-associated genes and antimicrobial resistance indicates the emergence of pathogenic clones which are well adapted and higher virulent.

Keywords:

pslA, pelA, Pseudomonas aeruginosa, Respiratory Infections

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