Biofilms in chronic wounds

Abstract

Chronic wounds including diabetic foot ulcers, pressure ulcers, and venous leg ulcers are a worldwide health problem. It has been speculated that bacteria colonizing chronic wounds exist as highly persistent biofilm communities. This research examined chronic and acute wounds for biofilms and characterized microorganisms inhabiting these wounds. Chronic wound specimens were obtained from 77 subjects and acute wound specimens were obtained from 16 subjects. Culture data were collected using standard clinical techniques. Light and scanning electron microscopy techniques were used to analyze 50 of the chronic wound specimens and the 16 acute wound specimens. Molecular analyses were performed on the remaining 27 chronic wound specimens using denaturing gradient gel electrophoresis and sequence analysis. Of the 50 chronic wound specimens evaluated by microscopy, 30 were characterized as containing biofilm (60%), whereas only one of the 16 acute wound specimens was characterized as containing biofilm (6%). This was a statistically significant difference (p<0.001). Molecular analyses of chronic wound specimens revealed diverse polymicrobial communities and the presence of bacteria, including strictly anaerobic bacteria, not revealed by culture. Bacterial biofilm prevalence in specimens from chronic wounds relative to acute wounds observed in this study provides evidence that biofilms may be abundant in chronic wounds.

Garlic ointment inhibits biofilm formation by bacterial pathogens from burn wounds

“…Previous studies have documented the production of bacterial biofilms at a range of infection sites and on a variety of different medical devices (Donlan & Costerton, 2002;Donlan, 2011;Macleod & Stickler, 2007). James et al (2008) reported the formation of polymicrobial biofilms within chronic wounds such as foot ulcers, venous leg ulcers and pressure ulcers. Additionally, using the murine model of thermal injury, Schaber et al (2007) described the formation of a P. aeruginosa biofilm within injured/infected tissues.…”

“…Within an infected wound, bacterial pathogens frequently exist within protective structures termed biofilms (Bjarnsholt et al, 2008;James et al, 2008). Biofilms are embedded in a glycocalyx, which is a combination of bacterial secreted extracellular polysaccharides that form a protective matrix adhering to the host's surrounding tissues (Stoodley et al, 2002;Sutherland, 2001).…”

Diabetic foot ulcers and biofilm formation- The culprits

“…This was unusual, as compared to prior studies in which it ranged from 73%-77.1%. [10] Such a deviation from the norm could be due to effective debridement procedures or shorter duration of ulcer in the patients. Therefore, liberal debridement in combination with appropriate antibiotics will help surgeons to effectively manage the situation and hereby decrease the incidence of emergence of multi drug resistant organisms thereby reducing mortality and the morbidity in patients.…”

“…(1,31) A study by James et al recorded a rate of 60% in chronic wounds, and 6% in acute wounds. [10] Such a deviation from the norm could be due to effective debridement procedures [31] or shorter duration of ulcer in the patients.…”

“…[9] Stepanovic et al described the tissue culture plate method in plastic microtitre plates. [10] On a sterile 96 well flat bottomed polystyrene microtitre plate, 230μl of Trypticase Soya Broth (TSB) was added. 20 μl of overnight bacterial culture was added to the corresponding well (each strain in three sucessive wells).The negative control wells contained broth only.…”