Identification of biofilm-producing microorganism’s and drug susceptibility pattern from diabetic foot ulcer patients at Puducherry

Abstract

Diabetes mellitus is a significant health problem worldwide that affects approximately 171 million people; severe complications lead to the development of diabetic foot ulcers. Diabetic ulcer infections are mainly polymicrobial in nature and multidrug-resistant (MDR), which is capable of forming a biofilm, which is the important virulence factor results in treatment failure. The main objectives of this study to investigate the etiologic agents of diabetic foot infections, their antimicrobial resistance and biofilm formation. A total of 200 patient samples were taken from diabetic foot ulcer patients between September 2015 and February 2016. Isolation and identification of microorganism were made according to standard microbiological procedures. Antibiotic Susceptibility testing performed by Kirby Bauer disc diffusion method and the biofilm production was performed by the tube method and Congo Red Method. Out of 200 samples processed, 110 (55%) were polymicrobial, 50 (25%) monomicrobial and 40(20 %)culture Sterile. The most common organism isolated were 82(39%) Pseudomonas aeruginosa,45(21%) Staphylococcus aureus, 48(23%) Candida sp followed by others. Biofilm production was seen in 112 (53%) of the isolates. Antimicrobial drug resistance was higher among 92(82%) biofilm producers than non-biofilm 20(18%) producing microorganisms. Organisms isolated from chronic diabetic foot ulcers cases were multidrug-resistant and biofilm producers. Our study shows the importance of biofilm screening with the usual antibiogram, as a routine technique in diabetic foot ulcers patients for effective treatment.