Prevalence of Biofilm-forming and Carbapenemase-producing Gram-negative Bacilli Colonizing Indwelling Urinary Catheters of Patients

The increasing prevalence of biofilm-forming and carbapenemase-producing Gram-negative Bacilli (GNB) in catheterized patients is linked to significant clinical challenges, including persistent infections, prolonged hospital stays, and higher colonization rates. To address these issues, establishing localized antimicrobial resistance (AMR) surveillance data is critical for guiding effective patient management and implementing robust infection prevention and control strategies. This study analyzed 200 indwelling urinary catheters (IUCs) from hospitalized patients using standard microbiological techniques, with isolates characterized using the VITEK 2 system. Phenotypic screening for biofilm production and carbapenem resistance was conducted using the Congo Red Assay and the Carba NP Test, respectively. Carbapenemase genes were identified via Polymerase Chain Reaction (PCR) with specific primers. Of the 200 samples, 164 (82.0%) were positive for GNB, with 87 (43.5%) identified as biofilm producers. Carbapenem resistance was confirmed in 89 (44.5%) isolates using CRE agar and the Carba NP Test. The distribution of carbapenemase genes among GNB isolates was as follows: blaKPC (29.5%), blaNDM (100%), blaVIM (13.5%), blaOXA (100%), and blaIMP (20.0%). Antibiogram analysis revealed high resistance rates (54.5%-100%) to amoxicillin-clavulanic acid, trimethoprim-sulfamethoxazole, ceftriaxone, meropenem, and ertapenem. However, susceptibility was observed to nitrofurantoin, ciprofloxacin, and Gentamicin, suggesting their potential as empiric treatments for GNB infections in catheterized patients. The study highlights the importance of adhering rigorously to structured catheter care protocols, including daily assessment of catheter necessity and strict adherence to aseptic techniques during insertion and maintenance. Regular training for healthcare staff on best practices for catheter management is essential to reduce colonization rates and improve clinical outcomes for patients at risk of carbapenem-resistant GNB (CR-GNB) infections. These findings highlight the urgent need for localized AMR surveillance and targeted infection control measures to mitigate the growing threat of multidrug-resistant GNB in healthcare settings.