International Journal of Multidisciplinary Health Sciences and Research

Category: Original Article,      DOI: Recived: 02/02/2024, Accepted: 18/03/2024, Published online: 29/03/2024

Assessment of Biofilm Formation in Clinical Isolates of Pseudomonas aeruginosa and Its Impact on Antibiotic Susceptibility

Simmi Singh1 , Priya Yadav2 , Naveen Kumar Prajapati3 , Suneet Yadav* 4

Abstract:

Background: Pseudomonas aeruginosa biofilms pose significant challenges in clinical settings due to their association with antibiotic resistance. This study aimed to assess biofilm formation in clinical isolates of P. aeruginosa and investigate its impact on antibiotic susceptibility. Methods: Two hundred non-duplicate P. aeruginosa clinical isolates were evaluated for biofilm formation using the microtiter plate method. Antibiotic susceptibility was determined by disk diffusion and broth microdilution methods. PCR detected biofilm-associated genes. Confocal laser scanning microscopy visualized biofilm architecture. Minimum biofilm eradication concentrations (MBEC) were compared to planktonic minimum inhibitory concentrations (MIC). Efflux pump involvement was assessed using inhibitors. Results: Biofilm formation was observed in 85% of isolates, with 20% classified as strong producers. Strong biofilm formation was significantly associated with increased resistance to carbapenems (OR 3.5, p<0.001) and ceftazidime (OR 3.2, p<0.001). The algD gene was most prevalent (90%) among biofilm-associated genes. MBEC values were consistently 64-fold higher than MIC values for all tested antibiotics. Efflux pump inhibition resulted in a ≥4-fold MIC reduction in 70% of isolates for ciprofloxacin. Conclusion: Biofilm formation in P. aeruginosa clinical isolates significantly impacts antibiotic susceptibility, emphasizing the need for biofilm-specific therapeutic strategies and susceptibility testing methods in clinical practice.