European Journal of Biomedical and Pharmaceutical Sciences

THE ASSOCIATION OF BIOFILM FORMATION WITH ANTIMICROBIAL RESISTANCE IN ACINETOBACTER BAUMANII COMPLEX ISOLATED FROM HOSPITAL ADMITTED PATIENTS

Puja Neopane, Durga Paudel, Rojeet Shrestha, Sushna Maharjan, Hari Prasad Nepal*

ABSTRACT

Background: Acinetobacter baumanii is one of the important emerging opportunistic pathogens that lead to serious nosocomial infections. Its major virulence properties, such as the ability to adhere to surfaces, the capacity to form microbial communities, and resistance to antimicrobial agents, make it difficult to control and eliminate. Therefore, this study was conducted to detect the association of biofilm formation with antimicrobial resistance in Acinetobacter baumanii complex (ABC) isolated from hospital admitted patients. Methods: One hundred clinical isolates of ABC derived from sputum, endotracheal tube secretions, blood, urine, and pus were obtained from patients admitted to Chitwan Medical College and Teaching Hospital. The isolates were identified by standard microbiological procedures. Biofilm formation was detected by the tissue culture plate method. Antimicrobial susceptibility was tested using modified Kirby-Bauer disk diffusion method as per CLSI guidelines. Multidrug resistance, extensive drug resistance and pandrug-resistance were determined and compared them among biofilm producers and non-producers. Results: ABC was remarkably associated with biofilm formation, i.e. 80% of the isolates were biofilm producers. Interestingly, all ABC isolated from endotracheal tube secretions were biofilm producers. The biofilm producing ABC showed a significantly higher (P<0.05) incidence of antimicrobial resistance compared to the biofilm non-producers for 17 antimicrobial agents tested. Of a total of 80 biofilm positive isolates, 71.25% were multidrug resistant, 3.75% were extensively drug resistant and 2.5% were pandrug resistant isolates. Multidrug resistance in biofilm producing isolates was found to be significantly (p<0.05) higher than in biofilm non-producing isolates. Conclusion: ABC isolates that have a high propensity to form a biofilm have a significant association with multiple drug resistance, aiding their ability to promote colonization and leading to persistent nosocomial infections. Therefore, early detection of the presence of a biofilm could aid the selection and delivery of an effective antimicrobial treatment strategy.

Keywords: A. baumanii complex, biofilm, antimicrobial resistance.