While virulence factors and the biofilm-forming capabilities of microbes are the key regulators of the wound healing process, the host immune response may also contribute in the events following wound closure or exacerbation of non-closure. We examined samples from diabetic and non-diabetic foot ulcers/wounds for microbial association and tested the microbes for their antibiotic susceptibility and ability to produce biofilms. A total of 1074 bacterial strains were obtained with staphylococci, Pseudomonas, Citrobacter and enterococci as major colonizers in diabetic samples. Though non-diabetic samples had a similar assemblage, the frequency of occurrence of different groups of bacteria was different. Gram-negative bacteria were found to be more prevalent in the diabetic wound environment while Gram-positive bacteria were predominant in non-diabetic ulcers. A higher frequency of monomicrobial infection was observed in samples from non-diabetic individuals when compared to samples from diabetic patients. The prevalence of different groups of bacteria varied when the samples were stratified according to age and sex of the individuals. Several multidrug-resistant strains were observed among the samples tested and most of these strains produced moderate to high levels of biofilms. The weakened immune response in diabetic individuals and synergism among pathogenic micro-organisms may be the critical factors that determine the delicate balance of the wound healing process.
BradyR. A., LeidJ. G., CalhounJ. H., CostertonJ. W., ShirtliffM. E.2008; Osteomyelitis and the role of biofilms in chronic infection. FEMS Immunol Med Microbiol 52:13–22 [View Article][PubMed]
CarsonL., GormanS. P., GilmoreB. F.2010; The use of lytic bacteriophages in the prevention and eradication of biofilms of Proteus mirabilis and Escherichia coli. FEMS Immunol Med Microbiol 59:447–455[PubMed]
CitronD. M., GoldsteinE. J. C., MerriamC. V., LipskyB. A., AbramsonM. A.2007; Bacteriology of moderate-to-severe diabetic foot infections and in vitro activity of antimicrobial agents. J Clin Microbiol 45:2819–2828 [View Article][PubMed]
DinhT., TecilazichF., KafanasA., DoupisJ., GnardellisC., LealE., TellecheaA., PradhanL., LyonsT. E.& other authors (2012; Mechanisms involved in the development and healing of diabetic foot ulceration. Diabetes 61:2937–2947 [View Article][PubMed]
GadepalliR., DhawanB., SreenivasV., KapilA., AmminiA. C., ChaudhryR.2006; A clinico-microbiological study of diabetic foot ulcers in an Indian tertiary care hospital. Diabetes Care 29:1727–1732 [View Article][PubMed]
Howell-JonesR. S., WilsonM. J., HillK. E., HowardA. J., PriceP. E., ThomasD. W.2005; A review of the microbiology, antibiotic usage and resistance in chronic skin wounds. J Antimicrob Chemother 55:143–149 [View Article][PubMed]
MartinJ. M., ZenilmanJ. M., LazarusG. S.2010; Molecular microbiology: new dimensions for cutaneous biology and wound healing. J Invest Dermatol 130:38–48 [View Article][PubMed]
MathurT., SinghalS., KhanS., UpadhyayD. J., FatmaT., RattanA.2006; Detection of biofilm formation among the clinical isolates of staphylococci: an evaluation of three different screening methods. Indian J Med Microbiol 24:25–29 [View Article][PubMed]
PatersonD. L., RossiF., BaqueroF., HsuehP.-R., WoodsG. L., SatishchandranV., SnyderT. A., HarveyC. M., TepplerH.& other authors (2005; In vitro susceptibilities of aerobic and facultative Gram-negative bacilli isolated from patients with intra-abdominal infections worldwide: the 2003 Study for Monitoring Antimicrobial Resistance Trends (SMART). J Antimicrob Chemother 55:965–973 [View Article][PubMed]
RamakantP., VermaA. K., MisraR., PrasadK. N., ChandG., MishraA., AgarwalG., AgarwalA., MishraS. K.2011; Changing microbiological profile of pathogenic bacteria in diabetic foot infections: time for a rethink on which empirical therapy to choose?. Diabetologia 54:58–64 [View Article][PubMed]
SrivastavaD., HarrisR. C., WatersC. M.2011; Integration of cyclic di-GMP and quorum sensing in the control of vpsT and aphA in Vibrio cholerae. J Bacteriol 193:6331–6341 [View Article][PubMed]
WangS.-H., SunZ.-L., GuoY.-J., YangB.-Q., YuanY., WeiQ., YeK.-P.2010; Meticillin-resistant Staphylococcus aureus isolated from foot ulcers in diabetic patients in a Chinese care hospital: risk factors for infection and prevalence. J Med Microbiol 59:1219–1224 [View Article][PubMed]
ZubairM., MalikA., AhmadJ.2011; Clinico-microbiological study and antimicrobial drug resistance profile of diabetic foot infections in North India. Foot (Edinb) 21:6–14 [View Article][PubMed]