Larvae have played an important part in clinical wound debridement for almost a century now. These resilient little creatures are able to debride a chronic wound bed in a matter of days, but how? This is what we are going to delve into, in today’s post.
Skins Extra Cellular Matrix (ECM) ensures a continuous turnover of cells, degraded and re-synthesized by proteolytic enzymes, also known as proteases. In turn, these proteases are managed by protease inhibitors, that keep everything balanced. Allowing for the body’s natural healing process to take place when an acute wound is inflicted.
The concern for clinicians encountering a chronic wound, is that these wounds do not follow the normal pattern of healing that we would expect to see. The ECM of chronic wounds is not healthy, and cells do not turnover as they should. Instead, chronic wounds are often stunted in their healing process, becoming trapped in the inflammatory stage. Making them very hard to heal.
Our aim as clinicians is to restore a healthy ECM within chronic injuries, aiding the wounds progression to proliferation. When a wound remains stagnant in the inflammatory stage, barriers arise in the form of slough, necrosis, eschar, and biofilm. These bacterial colonies provide a haven for infection, causing wounds to become increasingly uncomfortable for patients and difficult to manage for clinicians. Therefore the best option is usually to debride a chronic wound, removing devitalized tissue and the barriers to healing. With our focus primarily on Larval Therapy, let us explore exactly how larvae can debride a wound.
As we discussed, chronic wounds can be challenging. The unhealthy ECM is caused by an imbalance of proteases and proteases inhibitors. The great thing to know about larvae, is that they are powered by the same proteolytic enzymes that degrade skin naturally. Making larvae a fantastic match for debriding devitalized tissue.
Larvae debride a wound by secreting enzymes, allowing them to liquify necrotic tissue and ingest it. Often patients and clinicians can conjure up images of larvae chomping through a wound bed, but we assure you that larvae are completely toothless and use much more pleasant means of cleaning a wound, which we like to call microsurgery. As larvae ingest devitalized tissue, they can grow slightly, and in doing so scour away gently at the wound bed using exfoliating parts of their bodies, loosening any stubborn tissue as they travel. This is known as macrosurgery.
Through micro and macro surgery, larvae and their enzymes can rid a chronic wound of devitalized tissue in just a few days. Selective characteristics ensure larvae will only ever be interested in consuming unhealthy tissue; rest assured any surrounding skin is safe. Not forgetting to mention, debridement is not all that larvae are capable of. Larval secretions exhibit antimicrobial properties, meaning larvae are excellent destroyers of biofilms. Antibacterial properties allow them to effectively remove persistent infection from a wound. Pretty incredible, for such small creatures.