Marwa Mohammed Talib, Mansour Salem Attia, Ahmed Amrajaa Abdulrraziq
Pseudomonas aeruginosa is responsible for a high rate of burn wound infection. Biofilm formation enhances this pathogen's resistance to antibiotics. Quorum-sensing (QS) genes regulate biofilm production. Carbapenem resistance, particularly to imipenem (IMP), is a major challenge for physicians. The study aims to investigate the relationships among IMP resistance, lasR/rhlR QS genes, biofilm formation, and adhesion of P. aeruginosa to human oral mucosal epithelial cells (OMECs). Eleven P. aeruginosa isolates were obtained from burn wound infections; 45.5% were IMP-resistant. All IMP-resistant isolates were strong biofilm producers. A significant negative correlation was observed between IMP susceptibility, measured as the diameter of the inhibition zone (r = - 0.84, P < 0.005), and biofilm formation, measured as optical density at 590 nm. This finding indicates that biofilm formation in P. aeruginosa decreases IMP susceptibility. The current study also revealed that strong biofilm producers showed high adhesion to human OMECs. Polymerase chain reaction (PCR) screening detected lasR in 72.7% of P. aeruginosa isolates and rhIR in 81.8%, with both genes co-occurring in 72.7% and absent in 18.2%. The study revealed that one isolate had a lasR-negative/rhIR-positive profile. The study concluded that there is a strong relationship among QS gene carriage, biofilm production, adhesion to epithelial cells, and IMP resistance in P. aeruginosa.