Asian Journal of Microbiology, Biotechnology & Environmental Sciences Paper

BIOFILM PRODUCTION AND CARBAPENEM RESISTANCE IN CLINICAL ISOLATES OF ACINETOBACTER BAUMANNII IN A TERTIARY HEALTH CARE FACILITY AT KOLAR

PURNACHANDRA RAO UGGIRALA AND P.M. BEENA

Abstract

Acinetobacter baumannii is an important pathogen in health care associated infections. It occupies second position after Pseudomonas aeruginosa in causing infections in health care facilities. Ability to produce biofilm in A. baumannii has been associated with resistance to a wide range of drugs. Incidence of carbapenem resistance in A. baumannii infections is increasing day by day. So the present study was undertaken to find out association between biofilm production and carbapenem resistance in clinical isolates of A.baumannii and to evaluate the Tube method by comparing with Tissue culture method for the detection of biofilm formation. A total of 190 isolates of A. baumannii were collected from various clinical samples. Detection of biofilm production was done by Tube method and Tissue culture plate method. Detection of carbapenem resistance in biofilm producing and non-biofilm producing isolates were done by disc diffusion method. Among 190 isolates of A. baumannii 158 (83.15%) were able to form biofilms, out of them 113 (71.51%) were resistant to carbapenems. 32 (16.84%) isolates were non-biofilm producing strains, out of these 14 (43.75%) were carbapenem resistant strains. Carbapenem resistance was more in biofilm producing strains compared to non-biofilm producing strains and there was a significant association between carbapenem resistance and biofilm production (P = 0.02). Out of 190 isolates 158 (83.15%) were positive for biofilm production by Tissue culture plate method and 138 (72.6%) were positive for biofilm production by Tube method. Our study demonstrates that there is an association between biofilm production and carbapenem resistance in clinical isolates of A. baumannii and tube method is not a reliable method for the detection of biofilm producing organisms as compared to tissue culture plate method.