The pus samples of diabetic foot infection from 50 patients were collected and processed by standard microbiological techniques. Staphylococcus aureus was the predominant isolate recovered from 31 (67.4%) cases and the other organisms included Staphylococcus saprophyticus, Staphylococcus epidermidis, Streptococcus pneumoniae, Pseudomonas aeruginosa and Escherichia coli. Among the gram positive strains, the four strains of Staphylococcus aureus exhibited strong biofilm production by tube adherence method. Two of Pseudomonas aeruginosa strains were ESBL producer showing strong biofilm production by tube adherence and liquid interface cover slip method. Tube adherence (71.7%) and liquid interface cover slip assay (48%) were found to be the best conventional method for the detection of biofilm in this study. The results of this study suggest that the biofilm formation of the clinical isolates is an important virulence factor that complicates the treatment process resulting in progression of the infection leading to amputation. Hence proper screenings of the strains are very essential not only in the management of diabetic foot infections but also devising certain strategies in the prevention of biofilm by these isolates thereby preventing the development of drug resistant organism.
