Biofilm Management in Wound Care

Learning Objectives: After studying this article, the participant should be able to: 1. Understand the basics of biofilm infection and be able to distinguish between planktonic and biofilm modes of growth. 2. Have a working knowledge of conventional and emerging antibiofilm therapies and their modes of action as they pertain to wound care. 3. Understand the challenges associated with testing and marketing antibiofilm strategies and the context within which these strategies may have effective value. Summary: The Centers for Disease Control and Prevention estimate for human infectious diseases caused by bacteria with a biofilm phenotype is 65 percent and the National Institutes of Health estimate is closer to 80 percent. Biofilms are hostile microbial aggregates because, within their polymeric matrix cocoons, they are protected from antimicrobial therapy and attack from host defenses. Biofilm-infected wounds, even when closed, show functional deficits such as deficient extracellular matrix and impaired barrier function, which are likely to cause wound recidivism. The management of invasive wound infection often includes systemic antimicrobial therapy in combination with debridement of wounds to a healthy tissue bed as determined by the surgeon who has no way of visualizing the biofilm. The exceedingly high incidence of false-negative cultures for bacteria in a biofilm state leads to missed diagnoses of wound infection. The use of topical and parenteral antimicrobial therapy without wound debridement have had limited impact on decreasing biofilm infection, which remains a major problem in wound care. Current claims to manage wound biofilm infection rest on limited early-stage data. In most cases, such data originate from limited experimental systems that lack host immune defense. In making decisions on the choice of commercial products to manage wound biofilm infection, it is important to critically appreciate the mechanism of action and significance of the relevant experimental system. In this work, the authors critically review different categories of antibiofilm products, with emphasis on their strengths and limitations as evident from the published literature.