by the WoundSource Editors
Identifying and managing biofilms have become two of the most important aspects of wound care. Biofilms can have a significant impact...
by the WoundSource Editors
Advancements in molecular microbiology, microscopy technology, and techniques for study of bacteria have increased the ability to identify the existence of biofilms, but there still remains the unknown, such as differentiating between planktonic bacteria and biofilm.1 Chronic non-healing wounds harbor bacteria across the wound etiology classification.2–4 Malone et al. determined that the prevalence of biofilms in chronic wounds was 78.2% (confidence interval, 61.6–89, P < 0.002).2 The development of biofilms moves through a common pattern: attachment, microcolony formation, maturation, and dispersion. The initial attachment is reversible, but the attachment becomes stronger as cells multiply and change their gene expressions. This cell communication process is referred to as quorum sensing, allowing cells to survive.
Clinicians evaluating wounds should be thorough and detailed, including the clinical history, any signs and symptoms, and microscopic culture and tissue examination to help identify causative microorganisms.5 Conventional culturing methods lack sensitivity, and studies have proved the consistent failure of identifying types of organisms present within biofilm. DNA-based technology and molecular methods are better suited that conventional culturing methods for identifying biofilm colonies.6–10 Using a multidisciplinary approach, with good wound cleansing and established principles of wound care, will provide better healing outcomes. Research shows that microorganisms rarely invade healthy tissue unless the wound bed is compromised by drying out.11
Many strategies and therapies are most effective in suppressing biofilm activity in a wound. The goal is to target only the biofilm and not the defense and healing mechanisms of the body. Aggressive debridement, topical antiseptics, systemic antibiotics, DNA identification of microorganisms, and management of host factors (offloading, compression, diabetes, nutrition) are all components of a biofilm-based wound care approach.
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Debridement methods used to aid in biofilm eradication are utilized to prepare the wound bed to move toward healing. Keeping the wound bed clear of devitalized tissue and biofilm is imperative in enhancing wound healing progress. If biofilm colonies contaminate the wound bed, the transition to wound closure becomes complex.12,13 Combining debridement methods has been found to be an advantage in managing complex wounds and different pathological tissues since 2006.4 Developed biofilms harbor physical and metabolic defenses. These defenses enable the biofilm to resist antimicrobials that usually alienate planktonic cells and include resistance to host defenses, biocides, antibiotics, and ultraviolet light. Sequential sharp debridement of wounds disrupts biofilm growth and inhibitory factors and can promote faster healing. It is difficult to predict the outcome because we still do not know the depth needed to remove the entire biofilm colony.14
Finding the pieces of the puzzle to biofilms is an ongoing process. However, we know more now than a decade ago. Biofilms are known for their considerable defense protection from host immunities and utmost tolerance to antimicrobial agents. There are no normal standard signs and symptoms or precise methods to identify biofilms. Key essentials to preventing, disrupting, and suppressing biofilm regrowth are aggressive debridement, topical antibiofilm strategies, and host factor management strategies.
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2. Malone M, Bjarnsholt T, McBain AJ, et al. The prevalence of biofilms in chronic wounds: a systematic review and metaanalysis of published data. J Wound Care. 2017;26(1):20–5.
3. Seth AK, Geringer MR, Hong SJ, Leung KP, Mustoe TA, Galiano RD. In vivo modeling of biofilm-infected wounds: a review. J Surg Res. 2012;178(1):330–8.
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The views and opinions expressed in this blog are solely those of the author, and do not represent the views of WoundSource, Kestrel Health Information, Inc., its affiliates, or subsidiary companies.