INHIBITION OF BIOFILM PRODUCING GRAM NEGATIVE CLINICAL ISOLATES AND
THEIR ANTIBIOGRAM PATTERN
Abstract
Background: Bacterial biofilm is a major virulence factor that posses a
threat to patients leading to chronic infections. Therefore, it is
crucial to identify biofilm production as well as their inhibition and
reduction. This study was an attempt to investigate biofilm production
among gram-negative isolates and assessment of inhibitory and reduction
potential of EDTA and DMSO towards them and also observe the
antimicrobial resistance pattern among biofilm producers and biofilm
non-producer. Methods: Isolation and identification of bacterial
isolates were performed by standard microbiological methodology. The
antibiotic susceptibility pattern was determined by the Kirby Bauer disk
diffusion method and β-lactamases by the combination disk method.
Biofilm formation was detected through Tissue Culture Plate(TCP) method,
and different concentrations of EDTA and DMSO were used to determine
their inhibitory and reduction property against biofilm. Both inhibition
and reduction by the various concentration of EDTA and DMSO were
analyzed using paired t-test. Results: Among the 110 clinical isolates
61.8% were found to be Multidrug resistance(MDR) with the 33 (30%)
produced Extended-spectrum β-lactamases(ESBL), 16
(14.5%)Metalloβ-lactamases(MBL) and 9 (8%)Klebsiella pneumonia
carbapenemase(KPC). Biofilm formation was detected in 35.4% of
isolates. Biofilm producing organisms showed antibiotics resistance to
Cephalosporins, Chloramphenicol, Gentamycin, and Carbapenem. The
inhibition and reduction of biofilm were significantly lower
(p<0.05) for 1mM of EDTA and 2% of DMSO. Conclusions: EDTA
and DMSO were found to possess potential activity against biofilm.
Hence, EDTA and DMSO might be used invitro as an effective antibiofilm
agent to control the biofilm-associated infection and for a possible
therapeutic approach.