Limitations to the use of bromelain-based enzymatic debridement (NexoBrid®) for treating diabetic foot burns: a case series of disappointing results

The emerging role of nanoscaffolds in chronic diabetic wound healing: a new horizon for advanced therapeutics

Non-healing or chronic wounds in extremities that lead to amputations in patients with Type II diabetes (hyperglycemia) are among the most serious and common health problems in the modern world. Over the past decade, more efficient solutions for diabetic ulcers have been developed. Nanofibers and/or composite materials capable of drug delivery, moisture control, and antibacterial effectiveness are increasingly utilized in the formulation of wound dressings, with a particular focus on the biofunctionalization of polymeric and hydrogel materials. Natural products, including plant extracts, honey, antibacterial agents, nanozymes, and metal nanoparticles, are now commonly and effectively implemented to enhance the functionality of wound dressings. Due to the complicated and dysfunctional physiological structure of the chronic wound sites in the extremities of diabetic patients, formulated nanoscaffold or hydrogel components are becoming more intricate and versatile. This study aimed to investigate the development of wound dressing materials over the years while demonstrating their progressively enhanced complexity in effectively targeting, treating, and managing chronic wounds. The mechanisms of action and bio-functionality of wound dressing technologies were elucidated based on findings from 290 studies conducted over the last decade. A notable observation that emerged from these studies is the evolution of wound dressing development technology, which has led to significant advancements in the operational range of smart systems. These include, but are not limited to, self-healing, self-oxygenation, and adaptable mimicry of human tissue.

Foot Burns and Diabetes: A Systematic Review of Current Clinical Studies and Proposal of a New Treatment Algorithm

This study aims to systematically identify studies that evaluate lower extremity burn injury in the diabetic population, evaluate their clinical course and patient outcomes, and present a treatment algorithm tailored to diabetic burn patients. Our systematic review of the PubMed and Web of Science databases yielded 429 unique articles. After exclusion and inclusion criteria were applied, 59 articles were selected for evaluation. In diabetic patients, the thermal injury was largely a result of decreased awareness and education regarding heat therapies in the context of peripheral neuropathy. All noncase studies found that metrics such as hospital length of stay, ICU admission rates, rates of comorbidity, complication rates, scald injuries, infection rates, and cost of treatment were significantly increased in the diabetic burn population as compared to their nondiabetic counterparts. Where infection was present, microorganisms colonizing diabetic burn wounds were different than those found in the burn wounds of immunocompetent individuals. Operative intervention including split-skin graft, amputation, and debridement were more often utilized in diabetic burn patients. Foot burns in diabetic patients pose unique clinical risks to patients, and as such need to be an alternate treatment protocol to reflect their pathology. Education and training programs are crucial in the prevention of diabetic foot burns to avoid complications, protracted healing, and adverse outcomes. A unique algorithm can guide the unique treatment of this clinical entity.

Beneficial Properties of Bromelain

Bromelain is a major sulfhydryl proteolytic enzyme found in pineapple plants, having multiple activities in many areas of medicine. Due to its low toxicity, high efficiency, high availability, and relative simplicity of acquisition, it is the object of inexhaustible interest of scientists. This review summarizes scientific reports concerning the possible application of bromelain in treating cardiovascular diseases, blood coagulation and fibrinolysis disorders, infectious diseases, inflammation-associated diseases, and many types of cancer. However, for the proper application of such multi-action activities of bromelain, further exploration of the mechanism of its action is needed. It is supposed that the anti-viral, anti-inflammatory, cardioprotective and anti-coagulatory activity of bromelain may become a complementary therapy for COVID-19 and post-COVID-19 patients. During the irrepressible spread of novel variants of the SARS-CoV-2 virus, such beneficial properties of this biomolecule might help prevent escalation and the progression of the COVID-19 disease.

Historical Perspectives on the Development of Current Standards of Care for Enzymatic Debridement

Background and Objective: The use of plant-based products for burn treatment dates back to 1600 BC. Enzymatic debridement, which can be achieved as non-surgical or conservative debridement, has recently gained increasing attention. Several reviews have been published thus far. However, there has been no historical article including the achievements of the last 20 years, and this is the first review to present the achievements made in the field of enzymatic debridement in the last 20 years. This study aimed to present a historical overview of the development of enzymatic debridement until the present day. Methods: Enzymes from bacteria and plants were initially used for full-thickness burn treatment; however, they did not gain attention. Papain-derived products were the first plant-based products used for enzymatic debridement. Sutilains gained broad use in the 70s and 80s but came off market in the 1990s. Bromelain has been used for burn treatment owing to its strong debriding properties. NexoBrid^™ is used as a minimally invasive approach for enzymatic debridement of deep dermal burns. However, its use has been limited due to commercially available bromelain and the presence of four distinct cysteine proteinases. NexoBrid^™ involves faster eschar removal together with reduced blood loss, leading to improved long-term outcomes. However, research on nonoperative enzymatic debridement of burns has taken decades and is still ongoing. Results: Overall, the results of our study indicate that necrectomy, which has been used for a long time, remains the standard of care for burns. However, enzymatic debridement has several advantages, such as faster eschar removal, reduced blood loss, and reduced need for skin grafting, especially in cases of facial and hand burns. Enzymatic debridement cannot replace surgical intervention, as the enzyme only works on the surface of the eschar. Enzymatic debridement is not recommended in the early phase of scald burns. Conclusions: Enzymatic debridement has become an integral part of burn therapy and the standard of care in specific burn centers.

Effective enzymatic debridement of burn wounds depends on the denaturation status of collagen

The treatment of burn wounds by enzymatic debridement using bromelain has shown promising results in our burn center. However, inadequate debridement occurred in a few cases in which the etiology of the burn was attributed to relatively low temperature burns. We hypothesized that bromelain is ineffective in burns in which collagen denaturation, which occurs approximately at 65°C, has not taken place. Our objective was to assess whether there is a relationship between the denaturation of collagen and the ability of bromelain to debride acute scald burn wounds of different temperatures. Ex vivo human skin from four different donors was cut into 1x1 cm samples, and scald burns were produced by immersion in water at temperatures of 40°C, 50°C, 60°C, 70°C, and 100°C for 20 minutes. Denaturation of collagen was assessed with histology, using hematoxylin and eosin (H&E) staining and a fluorescently labeled collagen hybridizing peptide (CHP), and with second harmonic generation (SHG) microscopy. Burned samples and one control sample (room temperature) were weighed before and after application of enzymatic debridement to assess the efficacy of enzymatic debridement. After enzymatic debridement, a weight reduction of 80% was seen in the samples heated to 70°C and 100°C, whereas the other samples showed a reduction of 20%. Unfolding of collagen, loss of basket-weave arrangement, and necrosis was seen in samples heated to 60°C or higher. Evident CHP fluorescence, indicative of collagen denaturation, was seen in samples of 60°C, 70°C and 100°C. SHG intensity, signifying intact collagen, was significantly lower in the 70°C and 100°C group (P <.05) compared to the lower temperatures. In conclusion, denaturation of collagen in skin samples occurred between 60°C and 70°C and strongly correlated with the efficacy of enzymatic debridement. Therefore, enzymatic debridement with the use of bromelain is ineffective in scald burns lower than 60°C.

Limitations to the use of bromelain-based enzymatic debridement (NexoBrid®) for treating diabetic foot burns: a case series of disappointing results

BACKGROUND

Bromelain-based enzymatic debridement with Nexobrid® (Mediwound) is an alternative to traditional surgical tangential excision of deep dermal and full thickness burns. Early literature suggests that Nexobrid debridement could reduce the number of operations, infection rates, inpatient stay and the necessity for skin grafting to wounds by preserving viable tissue. To our knowledge there are no previous studies reporting the use of NexoBrid for treating burns in patients with established diabetic foot disease.

CASE PRESENTATION

We conducted a retrospective case series and identified four patients with diabetic foot burns that were treated with Nexobrid® debridement. All of these patients developed further eschar and deepening of their wounds a few days after NexoBrid was applied, requiring further surgery and skin grafting.

CONCLUSIONS

We would recommend judicious use of this new product in patients with diabetic foot wounds.