To evaluate the efficacy of an acellular Flowable matrix in comparison with a wet dressing for the treatment of patients with diabetic foot ulcers: a randomized clinical trial

Bioengineered Skin for Diabetic Foot Ulcers: A Scoping Review

Diabetic foot ulcers (DFUs) pose a significant threat to individuals with diabetes mellitus (DM), such as lower limb amputation and severe morbidity. Bioengineered skin substitutes (BSS) are alternatives to traditional interventions for treating DFUs, but their efficacy compared to standard wound care (SWC) or other treatment types, such as allografts, remains unknown. A scoping review of human studies was conducted to identify current approaches in the treatment of DFUs using BSS as compared with other treatment options. Systematic searches in PubMed, Cochrane Library, and Web of Science were conducted to identify comparative studies that enrolled 10 or more patients and evaluated wound healing outcomes (closure, time-to-healing, and area reduction). Database searches isolated articles published from 1 December 2012 to 1 December 2022 and were conducted in accordance with PRISMA-ScR guidelines. The literature search yielded 1312 articles, 24 of which were included for the qualitative analysis. Findings in these studies demonstrated that BSS outperformed SWC in all measured outcomes, suggesting that BSS may be a superior treatment for DFUs. Of the 24 articles, 8 articles compared human amniotic membrane allografts (hAMA) to BSS. Conflicting evidence was observed when comparing BSS and hAMA treatments, highlighting the need for future research.

Effectiveness and safety of dermal matrix used for diabetic foot ulcer: a systematic review and meta-analysis of randomized controlled trials

BACKGROUND

Diabetic foot ulcers (DFUs) have become a global health concern, which can lead to diabetic foot infection (DFI), lower leg amputation, and even mortality. Though the standard of care (SOC) practices have been recognized as the "gold standard" for DFU care, SOC alone may not be adequate to heal all DFUs and prevent their recurrence. The use of dermal matrix has emerged as an adjuvant treatment to enhance DFU healing. The current study aimed to evaluate the effectiveness and safety of dermal matrix application as an adjuvant treatment to the SOC.

METHODS

The databases of PubMed, Embase and CENTRAL were independently searched by two authors, with the following key terms: "diabetic foot ulcer", "acellular dermal matrix", "wound healing", and so on. Randomized controlled trials (RCTs) evaluated the efficacy and safety of dermal matrix in the treatment of DFUs were eligible for inclusion. The primary outcomes analyzed included time to complete healing and complete healing rate at the final follow-up, while secondary outcomes included wound area, ulcer recurrence rate, amputation risk and complication risk. Meta-analyses were performed using random-effect or fixed-effect models, based on the heterogeneity test.

RESULTS

This study included a total of 15 RCTs with a total of 1524 subjects. Of these, 689 patients were treated with SOC alone, while 835 patients received SOC plus dermal matrix. Compared to the SOC group, significantly shorter time (MD = 2.84, 95%CI: 1.37 ~ 4.32, p < 0.001***) was required to achieve complete healing in dermal matrix group. Significantly higher complete healing rate (OR = 0.40, 95%CI: 0.33 ~ 0.49, p < 0.001***) and lower overall (RR = 1.83, 95%CI: 1.15 ~ 2.93, p = 0.011*) and major (RR = 2.64, 95%CI: 1.30 ~ 5.36, p = 0.007**) amputation risks were achieved in dermal matrix group compared to SOC group. No significant difference was found in the wound area, ulcer recurrence rate, and complication risk between the two groups.

CONCLUSIONS

The application of dermal matrix as an adjuvant therapy in conjunction with SOC effectively improved the healing process of DFUs and reduced the amputation risk when compared to SOC alone. Furthermore, dermal matrix application was well tolerated by the subjects with no added complication risk.

Molecular implications of glycosaminoglycans in diabetes pharmacotherapy

Diabetes mellitus causes a wide range of metabolic derangements with multiple organ damage. The microvascular and macrovascular complications of diabetes result partly from the damage to the glycosaminoglycans (GAG) in the basement membrane. GAGs are negatively charged polysaccharides with repeating disaccharide units. They play a significant role in cellular proliferation and signal transduction. Destruction of extracellular matrix results in diseases in various organs including myocardial fibrosis, retinal damage and nephropathy. To substitute the natural GAGs pharmacotherapeutically, they have been synthesized by using basic disaccharide units. Among the four classes of GAGs, heparin is the most widely studied. Recent studies have revealed multiple significant GAG-protein interactions suggesting their use for the management of diabetic complications. Moreover, they can act as biomarkers for assessing the disease progression. A number of GAG-based therapeutic agents are being evaluated for managing diabetic complications. The current review provides an outline of the role of GAGs in diabetes while covering their interaction with different molecular players that can serve as targets for the diagnosis, management and prevention of diabetes and its complications. The medicinal chemistry and clinical pharmacotherapeutics aspects have are covered to aid in the establishment of GAG-based therapies as a possible avenue for diabetes.

The clinical efficacy of collagen dressing on chronic wounds: A meta-analysis of 11 randomized controlled trials

Objective

This study aims to evaluate the clinical efficacy of collagen dressing for patients with chronic wounds.

Materials and methods

Relevant randomized controlled trials were searched from the databases such as PubMed, EMBASE, and the Cochrane library as of January 2022. For dichotomous outcomes and continuous outcomes, risk ratio and mean difference were calculated, respectively. Subgroup analysis was performed according to the type of chronic ulcer and follow-up. In addition, trial sequential analysis (TSA) was performed to further verify the results. Jadad score was used to assess the quality of trials. The Grading of Recommendations Assessment, Development, and Evaluation (GRADE) was utilized to assess the level of evidence for outcomes.

Results

In 11 studies, a total of 961 patients of whom 485 were in the collagen group. Compared with standard of care (SOC) alone, the group that added an extra collagen dressing achieved a higher wound healing rate (Risk Ratio = 1.53; 95% CI, 1.33–1.77). The collagen group also showed a higher healing velocity than the SOC group (Mean Difference, 2.69; 95% CI, 0.87–4.51). In addition, the adverse events related to dressing between the two groups were similar (Risk Ratio = 0.67; 95% CI, 0.44–1.01).

Conclusion

Collagen dressing increases the wound healing rate and may be an effective and safe treatment for chronic wound management. However, more extensive research shall be conducted to substantiate these results.

Systematic review registration

https://www.crd.york.ac.uk/PROSPERO/display_record.php?RecordID=245728, identifier: CRD42021245728.

Use of a flowable wound matrix to treat lower limb vascular ulcers

OBJECTIVES

This study is aimed at assessing the safety and effectiveness of an advanced flowable wound matrix (FWM) in the treatment of hard-to-heal vascular leg ulcers that often involve deep structures, are irregular and/or tunnelled or excavated.

METHODS

Records of patients seen at our Vascular Surgery Unit, at the University of Campania 'Luigi Vanvitelli', for hard-to-heal vascular leg ulcers between January 2018 and January 2020 were retrospectively reviewed. For each wound aetiology, area and complications were recorded and evaluated. Every patient received one or more applications of FWM and was followed up.

RESULTS

A total of 22 patients (18 female/four male), mean age 63±8.5 years, were treated. The initial wound area ranged from 4-58cm². After wound bed preparation, FWM was applied. Treatment was well tolerated and effective-rate of complications was low, graft take was very satisfactory, and no graft loss, rejection or superimposed infections were observed. Healing time was short: 85% of ulcers healed after 12 weeks. Most importantly, there was a decrease in the rate and level of amputations as compared with standard wound care.

CONCLUSIONS

The data presented indicate that FWM is an option for the treatment of hard-to-heal vascular leg ulcers, particularly for those with an irregular cavity.

DECLARATION OF INTEREST

The authors have no conflicts of interest.

Diabetic Wound-Healing Science

Diabetes mellitus is an increasingly prevalent chronic metabolic disease characterized by prolonged hyperglycemia that leads to long-term health consequences. It is estimated that impaired healing of diabetic wounds affects approximately 25% of all patients with diabetes mellitus, often resulting in lower limb amputation, with subsequent high economic and psychosocial costs. The hyperglycemic environment promotes the formation of biofilms and makes diabetic wounds difficult to treat. In this review, we present updates regarding recent advances in our understanding of the pathophysiology of diabetic wounds focusing on impaired angiogenesis, neuropathy, sub-optimal chronic inflammatory response, barrier disruption, and subsequent polymicrobial infection, followed by current and future treatment strategies designed to tackle the various pathologies associated with diabetic wounds. Given the alarming increase in the prevalence of diabetes, and subsequently diabetic wounds, it is imperative that future treatment strategies target multiple causes of impaired healing in diabetic wounds.

Hard-to-heal wound treated with Integra Flowable Wound Matrix: analysis and clinical observations

Skin healing defects severely impair the quality of life of millions of people and burden healthcare systems globally. The therapeutic approach to these pathologies still represents a challenge. Novel scaffolds, used as dermal substitutes, possibly represent a promising strategy in complex wound management. Integra Flowable Wound Matrix (IFWM) is composed of a lyophilised, micronised form of collagen/chondroitin sulphate matrix, already used in regenerative medicine and endorsed in the therapy of diabetic foot lesions. In this paper, IFWM was applied to a tunnelling hard-to-heal skin lesion in order to restore tissue integrity. Although the different phases of skin wound healing are well established, the molecular mechanism underpinning IFWM-induced tissue repair are almost unknown. Here, we report, for the first time, the comparative analysis of molecular, histological and clinical observations of the healing process of a hard-to-heal tunnelling skin wound. The therapeutic success of this clinical case allowed us to recommend the use of IFWM as a tissue substitute in this rare type of hard-to-heal wound in which the high inflammatory status hampered the natural healing process.

Expanded negative pressure wound therapy in healing diabetic foot ulcers: a prospective randomised study

OBJECTIVE

This study aims to evaluate the benefits of treating diabetic foot ulcers (DFU) through a revised procedure using the mechanisms underlying negative pressure wound therapy (NPWT) in such a way as to achieve reduced and more evenly distributed lateral tension lines across the wound.

METHOD

Patients with type 2 diabetes were assessed for elegibility. Included patients were divided randomly into two groups: the NPWT control group and the NPWT+ group. Patients in the NPWT control group were treated in the traditional manner: wounds were covered with foams shaped to fit the wound precisely. In the NPWT+ group, foams were shaped to fit the wound precisely, and an additional foam was then wrapped around the foot.

RESULTS

Some 85 patients were assessed for eligibility; 59 were randomised into two groups: 29 patients in the NPWT+ group and 30 patients in the NPWT group. The primary objective was median healing time (NPWT+ 19 days, interquartile ratio (IQR) 7.5; NPWT 33 days, IQR 16; p<0.00001), and complete wound healing at three weeks (NPWT+ 55.20% NPWT 26.70% p=0.02). Secondary endpoints included number of major amputations (none in either group) and number of infections (NPWT+ 3.44% of patients, NPWT 6.66% of patients; p=0.57).

CONCLUSION

Our initial findings show that this treatment significantly reduced wound closure times and accelerated healing in DFUs. It also demonstrated promising improvements in healing rates, with no significant increase in wound complications.

Acellular Dermal Matrix Used in Diabetic Foot Ulcers: Clinical Outcomes Supported by Biochemical and Histological Analyses

Diabetic foot ulcer (DFU) is a diabetes complication which greatly impacts the patient's quality of life, often leading to amputation of the affected limb unless there is a timely and adequate management of the patient. DFUs have a high economic impact for the national health system. Data have indeed shown that DFUs are a major cause of hospitalization for patients with diabetes. Based on that, DFUs represent a very important challenge for the national health system. Especially in developed countries diabetic patients are increasing at a very high rate and as expected, also the incidence of DFUs is increasing due to longevity of diabetic patients in the western population. Herein, the surgical approach focused on the targeted use of the acellular dermal matrix has been integrated with biochemical and morphological/histological analyses to obtain evidence-based information on the mechanisms underlying tissue regeneration. In this research report, the clinical results indicated decreased postoperative wound infection levels and a short healing time, with a sound regeneration of tissues. Here we demonstrate that the key biomarkers of wound healing process are activated at gene expression level and also synthesis of collagen I, collagen III and elastin is prompted and modulated within the 28-day period of observation. These analyses were run on five patients treated with Integra® sheet and five treated with the injectable matrix Integra® Flowable, for cavitary lesions. In fact, clinical evaluation of improved healing was, for the first time, supported by biochemical and histological analyses. For these reasons, the present work opens a new scenario in DFUs treatment and follow-up, laying the foundation for a tailored protocol towards complete healing in severe pathological conditions.

Update of Topical Interventions for Healing Diabetic Ulcers-A Systematic Review

There are a variety of dressings for wound healing. For this reason, research can assist in the choice and proper use of the intervention. This current view of the effectiveness of dressing on diabetic foot ulcers (DFUs) in patients with type 2 diabetes mellitus. This study is a systematic review of clinical trials selected in 4 databases: PubMed, Scopus, Web of Science, and Cochrane. Studies without language restriction, published between 2009 and 2020, were included. The search resulted in the identification of 5651 articles, of which 58 met all inclusion criteria. Among these, 2 biomaterials (D-acellular dermal matrix and keratinocyte) and phenytoin were highlighted for achieving healing rates of 100% and 95.82% ± 2.22%, respectively. The literature presents several alternatives with different actions, cure rates, reduction rates, and varied cost benefits. The growth in the use of biomaterials for the treatment of DFU can be seen in this study.

Complete wound closure following a single topical application of a novel autologous homologous skin construct: first evaluation in an open-label, single-arm feasibility study in diabetic foot ulcers

Diabetic foot ulcers (DFUs) are a growing burden on patients and health care systems that often require multiple treatments of both conventional and advanced modalities to achieve complete wound closure. A novel autologous homologous skin construct (AHSC) has been developed to treat cutaneous defects with a single topical application, by leveraging the endogenous repair capabilities of the patient's healthy skin. The AHSC's ability to close DFUs with a single treatment was evaluated in an open-label, single-arm feasibility study. Eleven patients with DFUs extending up to tendon, bone, or capsule received a single topical application of AHSC. Closure was documented weekly with high-resolution digital photography and wound planimetry. All 11 DFUs demonstrated successful graft take. Ten DFUs closed within 8 weeks. The median time-to-complete closure was 25 days. The mean percent area reduction for all 11 wounds at 4 weeks was 83%. There were no adverse events related to the AHSC treatment site. This pilot study demonstrated AHSC may be a viable single application topical intervention for DFUs and warrants investigation in larger, controlled studies.

Effectiveness of interventions to enhance healing of chronic foot ulcers in diabetes: a systematic review

The management of diabetic foot ulcers (DFU) remains a challenge, and there is continuing uncertainty concerning optimal approaches to wound healing. The International Working Group of the Diabetic Foot (IWGDF) working group on wound healing has previously published systematic reviews of the evidence in 2008, 2012 and 2016 to inform protocols for routine care and to highlight areas which should be considered for further study. The working group has now updated this review by considering papers on the interventions to improve the healing of DFU's published between June 2014 and August 2018. Methodological quality of selected studies was independently assessed by a minimum of two reviewers using the recently published 21-point questionnaire as recommended by IWGDF/European Wound Management Association, as well as the previously incorporated Scottish Intercollegiate Guidelines Network criteria. Of the 2275 papers identified, 97 were finally selected for grading following full text review. Overall, there has been an improvement in study design and a significant rise in the number of published studies. While previous systematic reviews did not find any evidence to justify the use of newer therapies, except for negative pressure wound therapy in post-surgical wounds, in this review we found additional evidence to support some interventions including a sucrose-octasulfate dressing, the combined leucocyte, fibrin and platelet patch as well as topical application of some placental membrane products, all when used in addition to usual best care. Nonetheless, the assessment and comparison of published trials remains difficult with marked clinical heterogeneity between studies: in patient selection, study duration, standard of usual care provision and the timing and description of the clinical endpoints.

Guidelines on use of interventions to enhance healing of chronic foot ulcers in diabetes (IWGDF 2019 update)

The International Working Group on the Diabetic Foot (IWGDF) has published evidence-based guidelines on the prevention and management of diabetic foot disease since 1999. In conjunction with advice from internal and external reviewers and expert consultants in the field, this update is based on a systematic review of the literature centred on the following: the Population (P), Intervention (I), Comparator (C) and Outcomes (O) framework; the use of the SIGN guideline/Cochrane review system; and the 21 point scoring system advocated by IWGDF/EWMA. This has resulted in 13 recommendations. The recommendation on sharp debridement and the selection of dressings remain unchanged from the last recommendations published in 2016. The recommendation to consider negative pressure wound therapy in post-surgical wounds and the judicious use of hyperbaric oxygen therapy in certain non-healing ischaemic ulcers also remains unchanged. Recommendations against the use of growth factors, autologous platelet gels, bioengineered skin products, ozone, topical carbon dioxide, nitric oxide or interventions reporting improvement of ulcer healing through an alteration of the physical environment or through other systemic medical or nutritional means also remain. New recommendations include consideration of the use of sucrose-octasulfate impregnated dressings in difficult to heal neuro-ischaemic ulcers and consideration of the use of autologous combined leucocyte, platelet and fibrin patch in ulcers that are difficult to heal, in both cases when used in addition to best standard of care. A further new recommendation is the consideration of topical placental derived products when used in addition to best standard of care.

The Efficacy and Safety of Acellular Matrix Therapy for Diabetic Foot Ulcers: A Meta-Analysis of Randomized Clinical Trials

BACKGROUND

Acellular matrix (AM) therapy has shown promise in the treatment of diabetic foot ulcers (DFUs) in several studies. The clinical effects of AM therapy were not well established. Therefore, we conducted a meta-analysis of randomized clinical trials (RCTs) to examine the efficacy and safety of AM therapy for patients with DFUs.

METHODS

A literature search of 5 databases was performed to identify RCTs comparing AM therapy to standard therapy (ST) in patients with DFUs. The primary outcome was the complete healing rate and the secondary outcomes mainly included time to complete healing and adverse events.

RESULTS

Nine RCTs involving 897 patients were included. Compared with ST group, patients allocated to AM group had a higher complete healing rate both at 12 weeks (risk ratio (RR) = 1.73, 95% confidence interval (CI): 1.31 to 2.30) and 16 weeks (RR = 1.56, 95% CI: 1.28 to 1.91), a shorter time to complete healing (mean difference (MD) = -2.41; 95% CI: -3.49 to -1.32), and fewer adverse events (RR = 0.64, 95% CI: 0.44 to 0.93).

CONCLUSION

The present study suggests that AM therapy as an adjuvant treatment could further promote the healing of full-thickness, noninfected, and nonischemia DFUs. AM therapy also has a safety profile. More large well-designed randomized clinical trials with long follow-up duration are needed to further explore the efficacy and safety of AM therapy for DFUs.

Flowable Polyethylene Glycol Hydrogels Support the in Vitro Survival and Proliferation of Dermal Progenitor Cells in a Mechanically Dependent Manner

Cell-based therapies have garnered considerable interest largely because of their potential utility for tissue regeneration in a variety of organs, including skin. Designing vehicles that enable optimal delivery and purposeful integration of donor cells within tissues will be critical for their success. Here, we investigate the utility of an injectable, self-polymerizing, fully synthetic hydrogel in supporting the survival, proliferation, and function of cultured adult dermal progenitor cells (DPCs) which may serve as a source of renewable cells to repair severe skin injuries or restore hair growth. We show that modifying the stiffness of these transglutaminase cross-linked poly(ethylene glycol) (TG-PEG) hydrogels significantly alters DPC behavior and phenotype; increasing stiffness promotes their differentiation and migration whereas softer gels maintained them in a proliferative state. We found that 2-3% TG-PEG was optimal to promote cell expansion and survival. Unexpectedly, DPCs grown in all conditions maintained their inductive function and thus generated de novo hair follicles. Our data suggests that TG-PEG hydrogels may be a versatile platform for stem and progenitor cell transplantation and fate specification while maintaining functional competence.

Microbial production and metabolic engineering of chondroitin and chondroitin sulfate

Several commercial uses and potential novel applications have recently been described for chondroitin sulfate (CS). However, the currently applied animal extractive procedure has a high environmental impact, which may become more profound especially in relation to the forecasted expansion of the CS market for applications as a food supplement, pharmaceutical ingredient, and biopolymer in materials for regenerative medicine. This issue, together with religious and consumer concerns, has prompted the good manufacturing practice (GMP) of chondroitin and CS. This is achievable by combining the design of metabolically engineered microorganisms and tailor-made fermentation processes with semi-synthetic or enzyme-based approaches. The final target is to obtain molecules with specific sulfation patterns that resemble those occurring in natural products and improve the sulfation motif or introduce specific substitutions, such as fucosylation, to tune the biological function. The frontier that is currently triggering attention is related to evaluating the bioactivity of unsulfated chondroitin. Due to recent advancements in the field, a brief survey of the most recent patent and research literature is discussed here.

The Proteolytic Fraction from Latex of Vasconcellea cundinamarcensis (P1G10) Enhances Wound Healing of Diabetic Foot Ulcers: A Double-Blind Randomized Pilot Study

INTRODUCTION

The aim of the study was to investigate the role of the proteolytic fraction from Vasconcellea cundinamarcensis, designated as P1G10, on the healing of chronic foot ulcers in neuropathic patients with diabetes 2.

METHODS

Fifty patients were enrolled in a prospective, randomized, double-blind trial, to verify the efficacy and safety of a topical dressing formulated with 0.1% P1G10, intended for wound healing, versus a hydrogel (control) protocol. Upon completion of the intervention, the outcome evaluated the number of patients attaining full epithelization (100%), or at least 80% healing. Statistical analysis compared the data on each group for the significance of the differences.

RESULTS

Collection of data was finished in week 16, and the results were analyzed by intention to treat. The results showed that, in the control group, 5 patients attained 100% ulcer healing, 3 patients ≥ 80% healing and 11 experienced ulcer changes ≤ 80%, and the remainder showed no changes or their wounds became worse. Meanwhile, in the P1G10 group, 11 patients experienced full healing, 4 had healing ≥ 80% and 5 had ulcer changes ≤ lower than 80%, and the remainder showed no changes or their wounds became worse. The healing incidence for the first endpoint (100% healing) showed that the P1G10 group was 2.95-fold more efficacious than the control group (CI 95%) and 2.52-fold (CI, 95%) higher than its control for the second endpoint (80% healing).

CONCLUSIONS

These data support the hypothesis that topical application of the proteolytic fraction identified as P1G10 significantly enhances foot ulcer healing compared to hydrogel treatment.

Update on management of diabetic foot ulcers

Diabetic foot ulcers (DFUs) are a serious complication of diabetes that results in significant morbidity and mortality. Mortality rates associated with the development of a DFU are estimated to be 5% in the first 12 months, and 5-year morality rates have been estimated at 42%. The standard practices in DFU management include surgical debridement, dressings to facilitate a moist wound environment and exudate control, wound off-loading, vascular assessment, and infection and glycemic control. These practices are best coordinated by a multidisciplinary diabetic foot wound clinic. Even with this comprehensive approach, there is still room for improvement in DFU outcomes. Several adjuvant therapies have been studied to reduce DFU healing times and amputation rates. We reviewed the rationale and guidelines for current standard of care practices and reviewed the evidence for the efficacy of adjuvant agents. The adjuvant therapies reviewed include the following categories: nonsurgical debridement agents, dressings and topical agents, oxygen therapies, negative pressure wound therapy, acellular bioproducts, human growth factors, energy-based therapies, and systemic therapies. Many of these agents have been found to be beneficial in improving wound healing rates, although a large proportion of the data are small, randomized controlled trials with high risks of bias.