Biofilm Production and Antimicrobial Susceptibility Pattern of Pseudomonasaeruginosa Isolates from Post-Surgical Wound Infections

Objectives: The purpose of the study was to determine the prevalence of biofilm production and resistance to several antibiotics in P. aeruginosa isolated from post-surgical wound infections at a tertiary hospital. It also investigated the relationship between biofilm formation and drug resistance.Methods: The research was a cross-sectional study carried out between November 2024 and October 2025 on 116 non-duplicate P. aeruginosa isolates in patients with clinically diagnosed PSWIs. Standard microbiological techniques were used to identify isolates. The Kirby-Bauer disk diffusion technique was used to test antimicrobial susceptibility according to CLSI 2024 standards. The Tissue Culture Plate (microtiter plate) method was used to quantitatively measure biofilm production. Thestatistical analysis was conducted with SPSS 26.0, and the p-value was considered significant below 0.05.Results: Polymyxins (colistin and polymyxin B) exhibited the highest susceptibility rates (96.6% and 94.8%, respectively), while the lowest susceptibility was observed against ciprofloxacin (44.0%). Overall, 52 (44.8%; 95% CI: 35.9–53.9%) isolates were MDR, and 18 (15.5%; 95% CI: 9.5–23.5%) were XDR. Biofilm production was detected in 93 (80.2%) isolates, with 24 (20.7%) classified as strong producers. Using the Chi-square test for trend, we found a statistically significant relationship between biofilm formation and MDR (p < 0.001), with strong biofilm producers exhibiting markedly higher resistance to multiple antibiotics, including ciprofloxacin (87.5%) and meropenem (62.5%).Conclusion: The study shows high biofilm production and resistance to antimicrobials (MDR and XDR) of P. aeruginosa in post-surgical wound infections (PSWIs). This observation reveals a therapeutic dilemma, which suggests screening for biofilm and judicious use of antibiotics, along with adjunct therapies, such as biofilm-disrupting agents, to treat PSWIs.