Diabetic foot ulcers: Part I. Pathophysiology and prevention

Changes in Foot Skin Microbiome of Patients with Diabetes Mellitus Using High-Throughput 16S rRNA Gene Sequencing: A Case Control Study from a Single Center

Background

Worldwide, the treatment of complications associated with type 2 diabetes mellitus, including diabetic foot ulcer (DFU), results in an economic burden for patients and healthcare systems. This study aimed to use high-throughput 16S rRNA gene sequencing to investigate the changes in foot skin microbiome of patients with diabetes mellitus from a single center in China.

Material/Methods

Fifty-two participants were divided into 4 study groups: healthy controls (n=13); patients with short-term diabetes (<2 years; n=13); patients with intermediate-term diabetes (5–8 years; n=13); and patients with long-term diabetes (>10 years; n=13). Swabs were analyzed from the intact skin of the foot arch using high-throughput 16S ribosomal RNA sequencing.

Results

Microbiome phylogenic diversity varied significantly between the study groups (whole tree, P<0.01; Chao1, P<0.01), but were similar within the same group. The findings were supported by non-parametric multidimensional scaling (stress=0.12) and principal component analysis (principal component 1, 8.38%; principal component 2, 5.28%). In patients with diabetes mellitus, the dominant skin microbial phyla were Firmicutes, Proteobacteria, Actinobacteria, and Bacteroidetes.

Conclusions

High-throughput 16S rRNA gene sequencing showed dynamic changes in the skin microbiome from the foot during the progression of diabetes mellitus. These findings support the importance of understanding the role of the skin microbiota in the pathogenesis of DFU.

Compromised angiogenesis and vascular Integrity in impaired diabetic wound healing

Vascular deficits are a fundamental contributing factor of diabetes-associated diseases. Although previous studies have demonstrated that the pro-angiogenic phase of wound healing is blunted in diabetes, a comprehensive understanding of the mechanisms that regulate skin revascularization and capillary stabilization in diabetic wounds is lacking. Using a mouse model of diabetic wound healing, we performed microCT analysis of the 3-dimensional architecture of the capillary bed. As compared to wild type, vessel surface area, branch junction number, total vessel length, and total branch number were significantly decreased in wounds of diabetic mice as compared to WT mice. Diabetic mouse wounds also had significantly increased capillary permeability and decreased pericyte coverage of capillaries. Diabetic wounds exhibited significant perturbations in the expression of factors that affect vascular regrowth, maturation and stability. Specifically, the expression of VEGF-A, Sprouty2, PEDF, LRP6, Thrombospondin 1, CXCL10, CXCR3, PDGFR-β, HB-EGF, EGFR, TGF-β1, Semaphorin3a, Neuropilin 1, angiopoietin 2, NG2, and RGS5 were down-regulated in diabetic wounds. Together, these studies provide novel information about the complexity of the perturbation of angiogenesis in diabetic wounds. Targeting factors responsible for wound resolution and vascular pruning, as well those that affect pericyte recruitment, maturation, and stability may have the potential to improve diabetic skin wound healing.

Operative Intervention Does Not Change Pain Perception in Patients With Diabetic Foot Ulcers

Researchers investigated pain perception in patients with diabetic foot ulcers (DFUs) by analyzing pre- and postoperative physical function (PF), pain interference (PI), and depression domains of the Patient-Reported Outcome Measurement Information System (PROMIS). They hypothesized that 1) because of painful diabetic peripheral neuropathy (DPN), a majority of patients with DFUs would have high PROMIS PI scores unchanged by operative intervention, and 2) the initially assessed PI, PF, and depression levels would be correlated with final outcomes. Seventy-five percent of patients with DFUs reported pain, most likely because of painful DPN. Those who reported high PI and low PF were likely to report depression. PF, PI, and depression levels were unchanged after operative intervention or healing of DFUs.

Evaluation of Factors Affecting the Severity of Diabetic Foot Ulcer in Patients with Diabetes Referred to a Diabetes Centre in Kermanshah

INTRODUCTION

Diabetes mellitus is a metabolic disease characterized by high blood sugar (BS) levels and the change in the metabolism of lipids, carbohydrates, and insulin resistance, and is one of the main causes of disability and mortality worldwide. Among the different types of complications, which have many negative effects on personal and social life, diabetic foot ulcer (DFU) is very important. This study aims to investigate the factors affecting the severity of DFU among patients with diabetes.

METHODS

The study participants included 190 diabetic patients with a diagnosis of DFU. Data were collected using a two-part questionnaire for self-care awareness and functions in diabetic patients and Wagner's scale. The questionnaire was answered in cooperation with patients and the Wagner's score was estimated by a wound supervisor in the diabetes center.

RESULTS

There was 109 women (57.4%). Twenty-six patients had other diabetic complications as well as DFU. The average score of awareness in patients was 6.99±2.76 and the function was 62.22±9.92. The results found a direct relation between the age and the duration of illness with the score of the patient's awareness (P=0.008, P=0.000). There was also a direct relation between the level of education with score of awareness and the score of function in self-care (P=0.000, P=0.000), but the statistical results did not find any relation between awareness and the function in self-care of patients with the severity of DFU (P>0.05).

DISCUSSION

There was no relation between the self-care awareness and function with severity of DFU (P>0.05) that can be due to the more relation between DFU severity with hygiene and physical factors after the disease and the effect of awareness and function would be only in the incidence of the DFU.

CONCLUSION

Awareness and function of patients in self-care is less than average. Increasing awareness of patients and empowering them through appropriate training can be effective in preventing diabetic foot ulcers.

SIRT3 deficiency delays diabetic skin wound healing via oxidative stress and necroptosis enhancement

Sirtuin 3 (SIRT3) plays a vital role in several dermatological diseases. However, the role and detailed mechanism of SIRT3 in diabetic wound healing are unknown well yet. To explore possible involvement of SIRT3 and necroptosis in diabetic skin wound healing, SIRT3 knockout (KO) mice and 129S1/SvImJ wild‐type (WT) mice were injected with streptozotocin (STZ), and mice skin fibroblasts were exposed to high glucose (HG). It was found that SIRT3 expression decreased in the skin of diabetic patients. SIRT3 deficiency delayed healing rate, reduced blood supply and vascular endothelial growth factor expression, promoted superoxide production, increased malondialdehyde (MDA) levels, decreased total antioxidant capacity (T‐AOC), reduced superoxide dismutase (SOD) activity and aggravated ultrastructure disorder in skin wound of diabetic mice. SIRT3 deficiency inhibited mice skin fibroblasts migration with HG stimulation, which was restored by SIRT3 overexpression. SIRT3 deficiency also suppressed α‐smooth muscle actin (α‐SMA) expression, enhanced superoxide production but decreased mitochondrial membrane potential with HG stimulation after scratch. SIRT3 deficiency further elevated receptor‐interacting protein kinase 3 (RIPK3), RIPK1 and caspase 3 expression both in vitro and in vivo. Collectively, SIRT3 deficiency delayed skin wound healing in diabetes, the mechanism might be related to impaired mitochondria function, enhanced oxidative stress and increased necroptosis. This may provide a novel therapeutic target to accelerate diabetic skin wound healing.

c-Jun Overexpression Accelerates Wound Healing in Diabetic Rats by Human Umbilical Cord-Derived Mesenchymal Stem Cells

Objective

Mesenchymal stem cells (MSCs) are considered a promising therapy for wound healing. Here, we explored the role of c-Jun in diabetic wound healing using human umbilical cord-derived MSCs (hUC-MSCs).

Methods

Freshly isolated hUC-MSCs were subjected to extensive in vitro subcultivation. The cell proliferative and migratory capacities were assessed by the Cell Counting Kit-8 and scratch assays, respectively. c-Jun expression was evaluated by RT-PCR and western blot analysis. The function of c-Jun was investigated with lentivirus transduction-based gene silencing and overexpression. Diabetes mellitus was induced in SD rats on a high-glucose/fat diet by streptozocin administration. Wounds were created on the dorsal skin. The effects of c-Jun silencing and overexpression on wound closure by hUC-MSCs were examined. Reepithelialization and angiogenesis were assessed by histological and immunohistochemical analysis, respectively. Platelet-derived growth factor A (PDGFA), hepatocyte growth factor (HGF), and vascular endothelial growth factor (VEGF) levels were determined by western blot analysis.

Results

hUC-MSCs showed gradually decreased cell proliferation, migration, and c-Jun expression during subcultivation. c-Jun silencing inhibited cell proliferation and migration, while c-Jun overexpression enhanced proliferation but not migration. Compared with untransduced hUC-MSCs, local subcutaneous injection of c-Jun-overexpressing hUC-MSCs accelerated wound closure, enhanced angiogenesis and reepithelialization at the wound bed, and increased PDGFA and HGF levels in wound tissues.

Conclusion

c-Jun overexpression promoted hUC-MSC proliferation and migration in vitro and accelerated diabetic wound closure, reepithelization, and angiogenesis by hUC-MSCs in vivo. These beneficial effects of c-Jun overexpression in diabetic wound healing by hUC-MSCs were at least partially mediated by increased PDGFA and HGF levels in wound tissues.

Preclinical Models and Methodologies for Monitoring Staphylococcus aureus Infections Using Noninvasive Optical Imaging

In vivo whole-animal optical (bioluminescence and fluorescence) imaging of Staphylococcus aureus infections has provided the opportunity to noninvasively and longitudinally monitor the dynamics of the bacterial burden and ensuing host immune responses in live anesthetized animals. Herein, we describe several different mouse models of S. aureus skin infection, skin inflammation, incisional/excisional wound infections, as well as mouse and rabbit models of orthopedic implant infection, which utilized this imaging technology. These animal models and imaging methodologies provide insights into the pathogenesis of these infections and innate and adaptive immune responses, as well as the preclinical evaluation of diagnostic and treatment modalities. Noninvasive approaches to investigate host-pathogen interactions are extremely important as virulent community-acquired methicillin-resistant S. aureus strains (CA-MRSA) are spreading through the normal human population, becoming more antibiotic resistant and creating a serious threat to public health.

Factors Related to Severity of Diabetic Foot Ulcer: A Systematic Review

BACKGROUND

Diabetic foot ulcer (DFU) is one of the diabetes complications. DFU can be the cause of a high rate of amputation, health-care costs and even death, and this condition occurs in the severity status of DFU. Severity of DFU is the cause of expensive complication incidence. Understanding the factors affecting it can help preventive functions. Adequate evidence for this problem is necessary. The aim of this systematic review is to summarize evidence on severity of diabetic foot ulcer.

METHODS

A literature search was undertaken in Scopus, PubMed, Elsevier, MEDLINE, Embase, UpToDate and Google Scholar. Observational studies that assessed severity of DFU were included. The data extraction and assessment are on the basis of PRISMA.

RESULTS

Seven studies were assessed and 25 factors that affect severity of DFU are reported in the studies. The most used score for an estimate of severity was the Wagner scale (n=5). The majority of patients were in G1 and G2 stages (67.5%; basis of Wagner) or have a superficial ulcer (62.84%) on the basis of the Texas Diabetic Wound Classification System. The main factors include high BMI, smoking, lack of diabetes control, type of diabetes treatment and older age. In addition, there were other factors that affect severity of DFU such as vascular complications, bacteria isolated, marital status, gender, high levels of cholesterol and triglycerides. Also, life location, type 2 diabetes, genotype, addiction, long-time DFU and delay to refer patients were other factors.

CONCLUSION

Twenty-five factors were reported. The majority of these factors related to life-style and can be prevented by self-care functions. The effect of these factors needs further study and the further studies must be better in quality.

miRNA-221-3p in Endothelial Progenitor Cell-Derived Exosomes Accelerates Skin Wound Healing in Diabetic Mice

BACKGROUND

Patients with diabetic cutaneous ulcers experience financial burden and a lower quality of life and life expectancy. Endothelial progenitor cell (EPC)-derived exosomes facilitate skin wound healing by positively modulating vascular endothelial cell function. Exosomes play their important regulatory role through microRNA (miRNA). We explored the potential role and molecular mechanisms of miRNA in EPC-derived exosome healing of diabetic skin wounds.

METHODS

Exosomes were isolated from the media of EPCs derived from mice bone marrow. High-throughput sequencing was used to detect the expression of exosome miRNA, and miRNA target genes were predicted using online databases. A diabetic mouse skin wound model was established, and wounds were treated with exosomes, miRNA-221-3p, or phosphate-buffered saline.

RESULTS

Exosomes from EPCs accelerated skin wound healing in both control and diabetic mice. High-throughput sequencing showed that miRNA-221-3p was highly expressed in EPC-derived exosomes. Skin wound healing in control and diabetic mice was significantly enhanced by EPC-derived exosomes and miRNA-221-3p administration. Immunohistochemical analyses showed that EPC-derived exosomes and miRNA-221-3p increased protein expression levels of the angiogenesis-related factors VEGF, CD31 and cell proliferation marker Ki67. Bioinformatics analyses indicated that miRNA-221-3p may be involved in the AGE-RAGE signaling pathway in diabetic complications, cell cycle, and the p53 signaling pathway.

CONCLUSION

We concluded that miRNA-221-3p is one of the high-expressed miRNAs in EPC-derived exosomes and promoted skin wound healing in diabetic mice. The finding uncovers the molecular mechanism of EPC-derived exosomes and provides a potential novel approach to the clinical treatment of diabetic skin wounds.

Mevastatin promotes healing by targeting caveolin-1 to restore EGFR signaling

Diabetic foot ulcers (DFUs) are a life-threatening disease that often results in lower limb amputations and a shortened life span. Current treatment options are limited and often not efficacious, raising the need for new therapies. To investigate the therapeutic potential of topical statins to restore healing in patients with DFUs, we performed next-generation sequencing on mevastatin-treated primary human keratinocytes. We found that mevastatin activated and modulated the EGF signaling to trigger an antiproliferative and promigratory phenotype, suggesting that statins may shift DFUs from a hyperproliferative phenotype to a promigratory phenotype in order to stimulate healing. Furthermore, mevastatin induced a migratory phenotype in primary human keratinocytes through EGF-mediated activation of Rac1, resulting in actin cytoskeletal reorganization and lamellipodia formation. Interestingly, the EGF receptor is downregulated in tissue biopsies from patients with DFUs. Mevastatin restored EGF signaling in DFUs through disruption of caveolae to promote keratinocyte migration, which was confirmed by caveolin-1 (Cav1) overexpression studies. We conclude that topical statins may have considerable therapeutic potential as a treatment option for patients with DFUs and offer an effective treatment for chronic wounds that can be rapidly translated to clinical use.

The role of soluble urokinase plasminogen activator receptor (suPAR) in the diagnostics of diabetic foot infection

Background: To investigate the role of soluble urokinase plasminogen activator receptor (suPAR) in the diagnosis of diabetic foot infection and to determine whether it is superior to other infection markers like leukocyte, neutrophil, erythrocyte sedimentation rate, c-reactive protein and procalcitonin.Methods: The present prospective study consisted of four groups: Group 1, healthy volunteers (n = 38); Group 2, patients without diabetic foot ulcers (n = 40); Group 3, diabetic patients with uninfected foot ulcers (n = 33); and Group 4, patients who had diabetic foot infection (n = 48). In each group, the leukocyte, neutrophil, erythrocyte sedimentation rate, c-reactive protein and procalcitonin and suPAR levels were examined. The results were then statistically compared. In addition, the patients in Group 4 were further divided according to the presence of mild, moderate, and severe infection. Also osteomyelitis were evaluated in Group 4 and statistically compared.Results: All infection markers were significantly higher in group 4 patients than those in the other three groups (p < .05). Similarly, all infection markers in the severe diabetic foot infection group were statistically higher than mild diabetic foot infection group (p < .05); however, only suPAR and erythrocyte sedimentation rate were significantly high in cases with osteomyelitis (p < .05). In the receiver operating characteristic analysis, the optimal cut-off value for suPAR was determined to be 2.8 ng/ml, and the sensitivity and specificity above this value were 95.8% and 82.8%, respectively.Conclusions: The current study demonstrated that suPAR might be used as a supportive diagnostic method for the diagnosis of diabetic foot infections.

In vitro human cord blood platelet lysate characterisation with potential application in wound healing

Platelets contain abundant growth factors and cytokines that have a positive influence on the migration and proliferation of different cell types by modulating its physiopathological processes. As it is known that human umbilical cord blood platelet lysate (UCB-PL) contains a supraphysiological concentration of growth factors, in the present study, we investigated its effectiveness in wound-healing processes. Human UCB-PL was obtained by the freeze/thaw of platelet concentrate (1.1 × 10⁹ platelets/L), and its effect was evaluated on human or mouse endothelial cells, monocytes, fibroblasts, and keratinocytes in different concentrations. Human UCB-PL was observed to have high levels of pro-angiogenic growth factor than peripheral blood platelet-rich plasma. Among the cell lines, different concentrations of human UCB-PL were necessary to influence their viability and proliferation. For L929 cells, 5% of total volume was necessary, while for human umbilical vein endothelial cell, it was 10%. Cell migration on monocytes was increased with respect to the positive control, and scratch closure on keratinocytes was increased with respect to serum-free medium with only 10% of human UCB-PL. We concluded that the human UCB-PL may be useful to produce a large amount of standard platelet concentrates sufficient for several clinical-scale expansions avoiding inter-individual variability, which can also be used as a functional tool for clinical regenerative application for wound healing.

Current Therapeutic Strategies in Diabetic Foot Ulcers

Diabetic foot ulcers (DFUs) are the fastest growing chronic complication of diabetes mellitus, with more than 400 million people diagnosed globally, and the condition is responsible for lower extremity amputation in 85% of people affected, leading to high-cost hospital care and increased mortality risk. Neuropathy and peripheral arterial disease trigger deformities or trauma, and aggravating factors such as infection and edema are the etiological factors for the development of DFUs. DFUs require identifying the etiology and assessing the co-morbidities to provide the correct therapeutic approach, essential to reducing lower-extremity amputation risk. This review focuses on the current treatment strategies for DFUs with a special emphasis on tissue engineering techniques and regenerative medicine that collectively target all components of chronic wound pathology.

Diabetic Foot Ulcers: Current Advances in Antimicrobial Therapies and Emerging Treatments

Diabetic foot ulcers (DFUs) are very important diabetes-related lesions that can lead to serious physical consequences like amputations of limbs and equally severe social, psychological, and economic outcomes. It is reported that up to 25% of patients with diabetes develop a DFU in their lifetime, and more than half of them become infected. Therefore, it is essential to manage infection and ulcer recovery to prevent negatives outcomes. The available information plays a significant role in keeping both physicians and patients aware of the emerging therapies against DFUs. The purpose of this review is to compile the currently available approaches in the managing and treatment of DFUs, including molecular and regenerative medicine, antimicrobial and energy-based therapies, and the use of plant extracts, antimicrobial peptides, growth factors, ozone, devices, and nano-medicine, to offer an overview of the assessment of this condition.

Feasibility of a Low-Intensity, Technology-Based Intervention for Increasing Physical Activity in Adults at Risk for a Diabetic Foot Ulcer: A Mixed-Methods Study

BACKGROUND

Among adults with diabetes, 19-34% will develop a diabetic foot ulcer (DFU), which increases amputation risk and health care costs, and worsens quality of life. Regular physical activity, when increased gradually, may help prevent DFUs. In this mixed-methods study, we examined the feasibility of a low-intensity, technology-based behavioral intervention to increase activity in adults at risk for DFUs.

METHOD

Participants at risk for a DFU (n = 12; 66% female; mean age = 59.9 years) received four in-person exercise and behavioral counseling sessions over 2-3 weeks, supplemented with use of an activity monitor (to track steps) and text messages (to reinforce behavioral strategies) for an added 8 weeks. Pre- and postintervention assessments of accelerometer measured activity, daily mobility, and glycemic control (A1C) were completed. Treatment acceptability was assessed by questionnaire and via key informant interview.

RESULTS

The program appears feasible since all but one participant attended all four sessions, all used the activity monitor and all responded to text messages. Treatment acceptability (scale: 1 = very dissatisfied, 5 = extremely satisfied) was high; average item ratings were 4.79 (SD = 0.24). Participants increased their steps by an average of 881.89 steps/day (d = 0.66). A1C decreased on average by 0.33% (d = 0.23). Daily mobility did not change. Interview results suggest that participants perceived benefits from the intervention. Participant recommended improvements included providing more physical activity information, addressing pain, and intervention delivery in a podiatry clinic.

CONCLUSION

Individuals at risk for a DFU might benefit from a minimally intensive, technology-based intervention to increase their physical activity. Future research comparing the intervention to usual care is warranted.

Hyperglycemia-Induced Aberrant Cell Proliferation; A Metabolic Challenge Mediated by Protein O-GlcNAc Modification

Chronic hyperglycemia has been associated with an increased prevalence of pathological conditions including cardiovascular disease, cancer, or various disorders of the immune system. In some cases, these associations may be traced back to a common underlying cause, but more often, hyperglycemia and the disturbance in metabolic balance directly facilitate pathological changes in the regular cellular functions. One such cellular function crucial for every living organism is cell cycle regulation/mitotic activity. Although metabolic challenges have long been recognized to influence cell proliferation, the direct impact of diabetes on cell cycle regulatory elements is a relatively uncharted territory. Among other "nutrient sensing" mechanisms, protein O-linked β-N-acetylglucosamine (O-GlcNAc) modification emerged in recent years as a major contributor to the deleterious effects of hyperglycemia. An increasing amount of evidence suggest that O-GlcNAc may significantly influence the cell cycle and cellular proliferation. In our present review, we summarize the current data available on the direct impact of metabolic changes caused by hyperglycemia in pathological conditions associated with cell cycle disorders. We also review published experimental evidence supporting the hypothesis that O-GlcNAc modification may be one of the missing links between metabolic regulation and cellular proliferation.

Ultrasonic debridement management of lower extremity wounds: retrospective analysis of clinical outcomes and cost

Objective:

The aim of this study was to assess wound healing outcomes following direct, low-frequency, high-intensity, ultrasonic debridement as a surgical adjunct for non-healing lower extremity wounds.

Methods:

A retrospective review was conducted for patients undergoing lower extremity wound treatment with direct, low-frequency (22.5 kHz), high-intensity (~60 W/cm2) ultrasonic debridement between January 2010 and January 2016. Clinical outcomes were assessed up to 180-days post-ultrasonic debridement. Descriptive statistics, cost and univariate analysis were performed.

Results:

Overall, 82 wounds in 51 patients were included. Mean age was 57.0 years (range: 32–69), and average body mass index (BMI) was 30.8 kg/m². Patient comorbidities consisted of smoking (47%; n=24), hypertension (75%; n=38), diabetes (45%; n=23), and peripheral vascular disease (51%, n=26). Average wound age at initial presentation was 1013 days (range: 2–5475 days) with an average wound size of 9.0cm x 7.4cm. At 180-days post-debridement, 60% (n=49) of wounds had completely healed. Readmission (47%; n=24) and reoperation (45%; n=23) rates were characterised by the reason for readmission and reoperation respectively. Readmission for wound healing (70%, n=39) was primarily for further debridements (41%; n=16). Wound infection (30%; n=7) was the most common readmission for wound complications (30%; n=17). Reoperations primarily consisted of treatments for further wound healing 96% (n=51). Cost analysis showed a lower total treatment cost for patients with improved healing ($78,698), compared with non-improved wounds ($137,707).

Conclusion:

In a complex, heterogeneous cohort of chronic extremity wounds, the use of direct, low-frequency, high-intensity, ultrasonic debridement is a safe and reliable adjunctive therapy for the management of these wounds.

Mechanistic insight into diabetic wounds: Pathogenesis, molecular targets and treatment strategies to pace wound healing

Wound management in diabetic patient is of an extreme clinical and social concern. The delayed and impaired healing makes it more critical for research focus. The research on impaired healing process is proceeding hastily evident by new therapeutic approaches other than conventional such as single growth factor, dual growth factor, skin substitutes, cytokine stimulators, cytokine inhibitors, matrix metalloproteinase inhibitors, gene and stem cell therapy, extracellular matrix and angiogenesis stimulators. Although numerous studies are available that support delayed wound healing in diabetes but detailed mechanistic insight including factors involved and their role still needs to be revealed. This review mainly focuses on the molecular cascades of cytokines (with growth factors) and erstwhile factors responsible for delayed wound healing, molecular targets and recent advancements in complete healing and its cure. Present article briefed recent pioneering information on possible molecular targets and treatment strategies including clinical trials to clinicians and researchers working in similar area.

Lower limb wounds in diabetic and non-diabetic patients: survival analysis

OBJECTIVE

To evaluate the survival of wounds in lower limbs of diabetic and non-diabetic patients.

METHOD

Retrospective cohort study of patients with lower limb ulcers treated at a specialized center between 2011 and 2013. Outcome: healing of lower limb injuries in days. The survival function of lower limb wounds and the differences between diabetic and non-diabetic were analyzed. The Log-rank test was used to compare the survival curves between the study groups.

RESULTS

In up to 600 days, 23% of the diabetic patients presented wound healing, while 63% of the non-diabetic patients had their wounds healed, with a statistically significant difference in survival curves in comparison between the groups. The Hazard Ratios (RH) of healing were lower for diabetic patients (HR = 0.13, 95% CI = 0.02-0.97).

CONCLUSION

The results show that there is a delay in wound healing in diabetic patients.

Artificial neural networks in the selection of shoe lasts for people with mild diabetes

This research addressed the selection of shoe lasts for footwear design to help relieve the pain associated with diabetic neuropathy and foot ulcers. A reverse engineering (RE) technique was used to convert point clouds corresponding to scanned shoe lasts and diabetic foot data into stereo lithograph (STL) meshes. A slicing algorithm was developed and was used to find relevant girth features of diabetic foot and the shoe lasts. An artificial neural network, termed self-organizing map (SOM), classified 60 sets of shoe lasts into similar groups. Foot shapes of three mild diabetic patients were entered into the SOM feature categories to match with suitable shoe lasts. By conducting expert questionnaire analysis of the characteristic girths featured data with analytic hierarchy process (AHP), the weights of the girths were obtained. Grey relational analysis (GRA) was then used to calculate the correlation between foot girth and the corresponding range of shoe lasts. The most suitable shoe last for each patient with a mild diabetic foot can be determined by calculating the relative fitness function for each patient. By correlating diabetic foot with suitable shoe lasts, this study demonstrated an effective strategy for designing shoes for patients with mild diabetes, which can then be manufactured to meet customized requirements.

Necrotizing Soft Tissue Infections in the Vasculopathic Patient: Review of Literature

Background:

Necrotizing soft tissue infection is a surgical emergency associated with high mortality. Its presence in patients with risk factors for peripheral arterial disease such as diabetes mellitus is consistently associated with significantly poorer outcomes. Though it has been over a century since it was initially described in the literature, mortality rates remain high and treatment regimens are not standardized.

Materials and methods:

PubMed and Cochrane databases were searched for articles pertaining to necrotizing soft tissue infections. Articles were screened for relevance with the intent to compare outcomes in prospective studies of patients with diabetes mellitus or peripheral arterial disease. Patient demographics, clinical findings, mortality, rates of amputation, and morbidity were intended to be compared.

Results:

857 articles were identified, 165 duplicates were removed, and 6 prospective trials were identified for inclusion. Due to significant paucity of data, patient heterogeneity, and lack of standardization for surgical management, a descriptive review of the literature in relation to necrotizing soft tissue infections was pursued, with a focus on high-risk patients with peripheral arterial disease or diabetes mellitus.

Conclusions:

Early aggressive surgical intervention or major amputation may reduce mortality at the cost of increased disability and poorer quality of life in the long term, and may be appropriate in vasculopaths with poorly controlled diabetes and rapidly progressive fulminant infection. However, there is a deficiency in high-level evidence supporting surgical decision-making in this setting, with no standardized protocols for amputation. Future research will be needed to clarify the patient population who would benefit from radical amputation versus intention for limb salvage.

Modulation of vascular endothelial growth factor and mitogen-activated protein kinase-related pathway involved in extracorporeal shockwave therapy accelerate diabetic wound healing

Extracorporeal shockwave therapy (ESWT) has a significant positive effect to accelerate chronic wound healing. This study investigated whether the vascular endothelial growth factor (VEGF)-related pathway has involved in ESWT enhancement of diabetic wound healing. A dorsal skin defect (area, 6 × 5 cm) in a streptozotocin-induced diabetes rodent model was used. Thirty-two male Wistar rats were divided into four groups. Group I consisted of nondiabetic control; group II, diabetic control without treatment; group III, diabetic rats received ESWT; and group IV, rats received Avastin (a VEGF monoclonal antibody) on day 0 (post-wounding immediately) to day 7 and ESWT on day 3 and day 7. The wound healing was assessed clinically. The VEGF, endothelial nitric oxide synthase (eNOS), and Ki-67 were analyzed with immunohistochemical staining. The mRNA expression of mitogen-activated protein kinase-related genes was measured by real-time quantitative real-time polymerase chain reaction. The results revealed wound size was significantly reduced in the ESWT-treated rats as compared to the diabetic control (p < 0.01). The positive effect of ESWT-increasing wound healing was significantly suppressed in pretreatment of the Avastin group. Histological findings revealed significant increase in neo-vessels in the ESWT group as compared to the control. In immunohistochemical stain, significant increases in VEGF, eNOS, and Ki-67 expressions were noted in the ESWT group as compared to that in controls. However, Avastin suppressed the shockwave effect and down-regulation of VEGF, eNOS, and Ki-67 expressions in the Avastin-ESWT group as compared to that in the ESWT alone group. We found that highly mRNA expression of Kras, Raf1, Mek1, Jnkk, Jnk, and Jun at early stage in the ESWT group, as compared to the diabetic control. These evidences indicated treatment with multiple sessions of ESWT significantly enhanced diabetic wound healing associated with increased neovascularization and tissue regeneration. The bio-mechanism of ESWT-enhanced wound healing is correlated with VEGF and mitogen-activated protein kinase-mediated pathway.

Potential bactericidal activity of S. nux-vomica-ZnO nanocomposite against multidrug-resistant bacterial pathogens and wound-healing properties

Multidrug resistance in bacterial strains has become the greatest challenge for healthcare professionals for treating non-healing ulcers such as diabetic foot infections (DFI). Plant-mediated synthesis of S. nux-vomica-ZnO nanocomposite appears as a potential new alternative therapeutic agent that might be capable of tackling antibiotic-resistant bacterial pathogens and for treating a non-healing ulcer. The aim of the study was to investigate the antibacterial potential of S. nux-vomica-ZnO nanocomposite biosynthesised from Strychnos nux-vomica against multidrug-resistant organisms (MDROs) from DFU, wound-healing properties, and cytotoxic effects. The antibacterial potential was assessed by minimum inhibitory concentration (MIC)/ minimum bactericidal concentration (MBC) assays, time-kill kinetics, protein-leakage, and flow cytometric analysis. The wound-healing properties were assessed by scratch assay on mouse L929 fibroblastic cell line to quantify cell migration towards the injured area. Cytotoxicity was assessed using 3-[4,5-dimethyl-2-thiazol-yl]-2,5-diphenyl- 2H-tetrazolium bromide (MTT) cellular viability assay on the L929 cell line and human embryonic kidney epithelial (HEK-293) cell line. Strychnos nux-vomica-ZnO nanocomposite at a size range of 10-12 nm exhibited significant bactericidal potency at a concentration of 100-200 μg/ml against MDR-Methicillin-resistant Staphylococcus aureus, MDR-Escherichia coli, MDR-Pseudomonas aeruginosa, MDR-Acinetobacter baumannii, and also against standard bacterial strains S. aureus ATCC 29213, E. coli ATCC 25922, P. aeruginosa ATCC 27853, E. faecalis ATCC 29212. S. nux-vomica-ZnO nanocomposite also exhibited wound-healing and reduced cytotoxic properties at the antimicrobially active concentrations. Our findings thus suggested remarkable bactericidal properties of S. nux-vomica-ZnO nanocomposite and can be further exploited towards for the development of an antibacterial agent against the threatening superbugs.

Traditional Chinese Medicine Injections in the Treatment of Diabetic Foot: A Systematic Review and Meta-Analysis

CONTEXT

The role of traditional Chinese medicine injections (TCMIs) in diabetic foot (DF) has not been well estimated.

OBJECTIVE

To evaluate the clinical effective rate, safety, and the financial cost of TCMIs in treating DF and ulcer wound healing.

METHODS

We searched PubMed, Embase, CENTRAL, China National Knowledge Infrastructure (CNKI), VIP database, and Wanfang database from inception to May 2018 to find all randomized control trials (RCTs) related to TCMIs in DF treatment. The search items were "Traditional Chinese Medicine Injection" AND "Diabetic foot or Diabetic foot ulcer" AND "random".

STUDY SELECTION AND SYNTHESIS

Only RCTs of TCMIs combined conventional therapies versus conventional therapies and that can be quantitatively synthesized were included. Finally, 17 studies and 1294 participants were included after extraction. Two investigators independently extracted and analyzed the data using RevMan5.3 software.

RESULTS

The overall clinical effective rate of TCMI groups is higher than that of control groups [RR=1.27, 95CI % (1.20, 1.34), P<0.00001] based on fixed effect model analysis. Regarding motor nerve conduction velocity of median nerve and peroneal nerve, TCMI group showed a significant improvement (MD=3.84[2.28, 5.41], P<0.00001; MD=2.89[0.63, 5.15], P=0.01). Regarding plasma viscosity TCMI group showed a statistically difference (MD=0.27[0.04, 0.49], P=0.02). In terms of blood viscosity at high shear rate, there was an improvement of TCMI group (MD=0.36[0.05, 0.67], P=0.02). However, sensory nerve conduction velocity of peroneal nerve and median nerve showed a contradiction to motor nerve conduction velocity, respectively (MD=2.59[-1.69, 6.87], p=0.24; MD=2.73[-0.96, 6.43], P=0.15).

CONCLUSION

The data of this study shows that TCMIs can bring benefits to patients with diabetic foot. However, due to low methodological quality of included RCTs, more rigorous designed RCTs with large sample size are recommended to provide more high-quality evidence.

Wound healing of diabetic rats treated with Moringa oleifera extract

PURPOSE

To evaluate if Moringa oleifera leaf aqueous extract (ME) influences the healing of skin wounds of diabetic rats.

METHODS

Wistar rats were used (6 rats/group). Group 1 received normal saline (NS) v.o. Group 2 received moringa extract (100mg/kg v.o) for 3 weeks. Groups 3 and 4: Streptozotocin (STZ) induced diabetes. Group 3 received NS; Group 4 received aqueous ME (100mg/kg) v.o.The wounds of groups 1 and 3 rats were topically treated with NS; wounds of groups 2 and 4 treated with 200µL of 10% ME. After anesthesia, all rats had skin square excision wounds 1.5cm2. Wound percent contractions were measured. On 10th day, blood glucose and serum cytokines were measured. Histometry of wounds was studied using ImagePro6.0 software.

RESULTS

Glycemia was significantly reduced in ME treated rats. These rats had higher percent contraction of the wounds on 2nd, 5th and 10th days, then controls (p<0.05). Diabetic rats treated with NS had TNF-α, IL-1β and IL-6 expression higher than in rats receiving ME. The histopathological score of ME treated diabetic rats (198±13.7) was significantly higher than treatment with NS (145±10.5).

CONCLUSION

ME extract positively influenced healing of wounds in diabetic rats after systemic and topical treatment.

Ozone therapy for diabetic foot

Diabetic foot ulcers (DFU) are a burden to the diabetic community. With increasing medical bills, to unsuccessful treatment, those suffering from DFUs can use alternative therapeutics. First seen in the mid-1800s, ozone (O₃) is thought to be unstable, due to inherent molecular nature. With the help of pharmaceutical science, various O₃ treatments have flourished in the medical community to help those suffering from DFUs. Promising results are seen through numerous studies. Usually, a mixture of both O₂ and O₃ is seen in pressurized machines as administered to the foot ulcer. Foot ulcers, specifically DFUs, need to be assessed, cleaned, and treated as fast as possible for the fastest results. Results such as amputation can be seen if the foot is not attended to as soon as possible. With fast growing clinical trials in O₃ therapy and quick administration of the O₃, O₃ therapy may be on the rise to be at the forefront of treating DFUs. Compelling evidence is seen in clinical trials, but more must be done to fully understand the role of O₃ in DFUs.

A multicenter, randomized, single-blind trial comparing the efficacy of viable cryopreserved placental membrane to human fibroblast-derived dermal substitute for the treatment of chronic diabetic foot ulcers

Randomized controlled clinical trials, the gold standard to determine treatment efficacy against control, have demonstrated advantages of skin substitutes for the treatment of chronic diabetic foot ulcers in comparison to standard of care. However, randomized controlled clinical trials comparing efficacy between two or more skin substitutes are very limited. With growing numbers of new skin substitutes, such studies are essential for treatment and policy-making decisions by wound care providers and payers. In this study, we analyzed clinical outcomes and product cost between a viable cryopreserved placental membrane (vCPM) and a human fibroblast-derived dermal substitute (hFDS) for the treatment of chronic diabetic foot ulcers in a prospective, multicenter, single-blind study. The outcomes of 62 patients were analyzed: 31 patients in the vCPM treatment group and 31 patients in the hFDS treatment group. Utilizing a non-inferiority trial design and the established treatment regimen of 8 applications for hFDS, we demonstrated that vCPM was not inferior to hFDS for the proportion of patients achieving complete wound closure (9.68, 90% CI: [10.67, 28.94]). However, preliminary findings show that vCPM may have better outcomes for wounds ≤ 5 cm² : 81.3% (13/16) of wounds in the vCPM group vs. 37.5% (6/16) of wounds in the hFDS group reached complete closure at the end of treatment (p = 0.0118). A preliminary product cost analysis for wounds ≤ 5 cm² may show significant savings for patients treated with vCPM. Average per-patient costs during the course of treatment were $3,846 and $7,968 (p < 0.0001) for vCPM and hFDS patients, respectively. These results may be used as guidance to wound care providers and payers.

Quality assessment of diabetic foot ulcer clinical practice guidelines

OBJECTIVE

Nurses play an effective role in diabetic foot care and they should know the best evidence. In this way, implementations according evidence-based clinical practice guidelines have positive effects on nurses' practice and patient outcomes. The objective of this study was quality assessment of diabetic foot ulcer clinical practice guidelines.

METHODS

Evidence about nursing care in diabetic foot ulcer in last 5 years was searched and categorized based on nursing diagnosis (ND) and evidence levels and was finally designed as a guideline. Quality appraisal of guideline was evaluated with AGREEII tool by an expert panel. AGREEII consists of 23 items, grouped in six domains: scope and purpose, stakeholder involvement, rigor of development, clarity of presentation, applicability, and editorial independence. Applicability of the guideline in clinical was assessed with a checklist by the nursing group. Data analysis was carried out with SPSS v.18 (descriptive statistics and binomial test).

RESULTS

Of the 114 studies, evidence of 19 studies was selected. The guidelines had three parts: introduction, nursing recommendation, and appendix. Evidence was categorized according to 8 NDs. According to AGREEII, the guideline had the highest score in the "scope and purpose" (92.7%) and the lowest in "applicability" (76.2%) domains. Also, nurses reported the positive effect of implementation of guideline recommendations and lack of needed equipment for its implementation.

CONCLUSIONS

Guidelines received acceptable scores in all the domains of AGREEII. Based on nurses' opinion, recommendations of guidelines will play an effective role in prevention, treatment, reduction of complication among diabetic foot patients. Therefore, adaptation, implementation, and evaluation of the guidelines were recommended.

Smart Wound Dressings for Diabetic Chronic Wounds

Given their severity and non-healing nature, diabetic chronic wounds are a significant concern to the 30.3 million Americans diagnosed with diabetes mellitus (2015). Peripheral arterial diseases, neuropathy, and infection contribute to the development of these wounds, which lead to an increased incidence of lower extremity amputations. Early recognition, debridement, offloading, and controlling infection are imperative for timely treatment. However, wound characterization and treatment are highly subjective and based largely on the experience of the treating clinician. Many wound dressings have been designed to address particular clinical presentations, but a prescriptive method is lacking for identifying the particular state of chronic, non-healing wounds. The authors suggest that recent developments in wound dressings and biosensing may allow for the quantitative, real-time representation of the wound environment, including exudate levels, pathogen concentrations, and tissue regeneration. Development of such sensing capability could enable more strategic, personalized care at the onset of ulceration and limit the infection leading to amputation. This review presents an overview of the pathophysiology of diabetic chronic wounds, a brief summary of biomaterial wound dressing treatment options, and biosensor development for biomarker sensing in the wound environment.

Diabetic retinopathy in patients with diabetic foot syndrome in South India

Purpose

The purpose was to study the retinopathy status in diabetic patients with a risk of diabetic foot (DF) syndrome visiting a tertiary care hospital in South India.

Methods

In this cross sectional study all patients with diabetes mellitus (DM) with a risk of DF syndrome, visiting a tertiary care hospital during the study period, underwent an ophthalmological evaluation for documentation of their retinopathy status.

Results

One hundred and eighty-two patients diagnosed to have a risk profile for DF syndrome were included in the study. Their mean age was 59.28 years and 75.27% were males. The mean duration of Type 1 and Type 2 variants of DM was 14.9 years and 10.9 years, respectively. Of the 182 patients, 67.58% had retinopathy changes. Proliferative diabetic retinopathy (DR) constituted 17.88% of the total patients with retinopathy. An increased presence of retinopathy in patients with an increased risk grade of DF was found significant by the Chi-square test (P < 0.001).

Conclusion

Our study found an increased presence of DR in a South Indian cohort with DF syndrome. The severity of retinopathy was greater in patients with higher grades of risk for DF. The establishment of an association between DR and DF syndrome will help in developing an integrated management strategy for these two debilitating consequences of diabetes.

Easier operation and similar power of 10 g monofilament test for screening diabetic peripheral neuropathy

Objective

The 10 g Semmes–Weinstein monofilament evaluation (SWME) of 4 sites on each foot is recommended for distal symmetric polyneuropathy screening and diagnosis. A similar method has been proposed to diagnose ‘high-risk’ (for ulceration) feet, using 3 sites per foot. This study compared the effectiveness of SWME for testing 3, 4 and 10 sites per foot to identify patients with diabetic neuropathy.

Methods

We included 3497 subjects in a SWME of 10 sites; records from the 10-site SWME were used for a SWME of 3 and 4 sites. Neuropathy symptom scores and neuropathy deficit scores were evaluated to identify patients with diabetic peripheral neuropathy.

Results

The sensitivities of the 10 g SWME for 3, 4 and 10 sites were 17.8%, 19.0% and 22.4%, respectively. The Kappa coefficients for the SWME tests of 3, 4 and 10 sites were high (range: 0.78–0.93).

Conclusions

There were no significant differences in the effectiveness of 3-, 4- and 10-site SWME testing for diabetic peripheral neuropathy screening. SWME testing of 3 sites on each foot may be sufficient to screen for diabetic neuropathy.

Pseudomonas aeruginosa infection alters the macrophage phenotype switching process during wound healing in diabetic mice

Macrophages play critical roles in wound healing process. They switch from "classically activated" (M1) phenotype in the early inflammatory phase to "alternatively activated" (M2) phenotype in the later healing phase. However, the dynamic process of macrophage phenotype switching in diabetic wounds burdened with bacteria is unclear. In this report, Pseudomonas aeruginosa, frequently detected in diabetic foot ulcers, was inoculated into cutaneous wounds of db/db diabetic mice to mimic bacterium-infected diabetic wound healing. We observed that P. aeruginosa infection impaired diabetic wound healing and quickly promoted the expression of pro-inflammatory genes (M1 macrophage markers) tumor necrosis factor-α (tnf-α), interleukin-1β (il-1β) and il-6 in wounds. The expression of markers of M2 macrophages, including il-10, arginase-1, and ym1 were also upregulated. In addition, similar gene expression patterns were observed in macrophages isolated directly from wounds. Immunostaining showed that P. aeruginosa infection increased both the ratios of M1 and M2 macrophages in wounds compared with that in control groups, which was further confirmed by in vitro culturing macrophages with P. aeruginosa and skin fibroblast conditioned medium. However, the ratios of the expression levels of pro-inflammatory genes to anti-inflammatory gene il-10 was increased markedly in P. aeruginosa infected wounds and macrophages compared with that in control groups, and P. aeruginosa prolonged the presence of M1 macrophages in the wounds. These data demonstrated that P. aeruginosa in diabetic wounds activates a mixed M1/M2 macrophage phenotype with an excessive activation of M1 phenotype or relatively inadequate activation of M2 phenotype.

A review of genetic engineering biotechnologies for enhanced chronic wound healing

Traditional methods for addressing chronic wounds focus on correcting dysfunction by controlling extracellular elements. This review highlights technologies that take a different approach - enhancing chronic wound healing by genetic modification to wound beds. Featured cutaneous transduction/transfection methods include viral modalities (ie adenoviruses, adeno-associated viruses, retroviruses and lentiviruses) and conventional non-viral modalities (ie naked DNA injections, microseeding, liposomal reagents, particle bombardment and electroporation). Also explored are emerging technologies, focusing on the exciting capabilities of wound diagnostics such as pyrosequencing as well as site-specific nuclease editing tools such as CRISPR-Cas9 used to both transiently and permanently genetically modify resident wound bed cells. Additionally, new non-viral transfection methods (ie conjugated nanoparticles, multi-electrode arrays, and microfabricated needles and nanowires) are discussed that can potentially facilitate more efficient and safe transgene delivery to skin but also represent significant advances broadly to tissue regeneration research.

Neutralizing Alpha-Toxin Accelerates Healing of Staphylococcus aureus-Infected Wounds in Nondiabetic and Diabetic Mice

Staphylococcus aureus wound infections delay healing and result in invasive complications such as osteomyelitis, especially in the setting of diabetic foot ulcers. In preclinical animal models of S. aureus skin infection, antibody neutralization of alpha-toxin (AT), an S. aureus-secreted pore-forming cytolytic toxin, reduces disease severity by inhibiting skin necrosis and restoring effective host immune responses. However, whether therapeutic neutralization of alpha-toxin is effective against S. aureus-infected wounds is unclear. Herein, the efficacy of prophylactic treatment with a human neutralizing anti-AT monoclonal antibody (MAb) was evaluated in an S. aureus skin wound infection model in nondiabetic and diabetic mice. In both nondiabetic and diabetic mice, anti-AT MAb treatment decreased wound size and bacterial burden and enhanced reepithelialization and wound resolution compared to control MAb treatment. Anti-AT MAb had distinctive effects on the host immune response, including decreased neutrophil and increased monocyte and macrophage infiltrates in nondiabetic mice and decreased neutrophil extracellular traps (NETs) in diabetic mice. Similar therapeutic efficacy was achieved with an active vaccine targeting AT. Taken together, neutralization of AT had a therapeutic effect against S. aureus-infected wounds in both nondiabetic and diabetic mice that was associated with differential effects on the host immune response.

Development and formulation of Moringa oleifera standardised leaf extract film dressing for wound healing application

ETHNOPHARMACOLOGICAL RELEVANCE

M.oleifera is a medicinal plant traditionally used for skin sores, sore throat and eye infections. Recently, the wound healing property of the leaves of M. oleifera was has been well demonstrated experimentally in both in vivo and in vitro models. However, there is a lack of research which focuses on formulating M.oleifera into a functional wound dressing. In this study, the M.oleifera leaf standardized aqueous extract with highest potency in vitro migration was formulated into a film for wound healing application.

MATERIALS AND METHODS

Firstly, M. oleifera leaf were extracted in various solvents (aqueous, 50%, 70% and 100% ethanolic extracts) and standardized by reference standards using UHPLC technique. The extracts were then tested for cell migration and proliferation using HDF and HEK cell lines. M. oleifera leaf aqueous extract was then incorporated into alginate-pectin (SA-PC) based film dressing. The film dressings were characterized for the physicochemical properties and the bioactives release from the M. oleifera leaf extract loaded film dressing was also investigated using Franz diffusion cells.

RESULTS

All extracts were found to contain vicenin-2, chlorogenic acid, gallic acid, quercetin, kaempferol, rosmarinic acid and rutin. Among all M. oleifera extracts, aqueous standardized leaf extracts showed the highest human dermal fibroblast and human keratinocytes cells proliferation and migration properties. Among the film formulations, SA-PC (3% w/v) composite film dressing containing M. oleifera aqueous leaf extract was found to possess optimal physicochemical properties as wound dressing.

CONCLUSION

A potentially applicable wound dressing formulated as an alginate-pectin film containing aqueous extracts of M. oleifera has been developed. The dressing would be suitable for wounds with moderate exudates.

Diabetic foot ulcer management in clinical practice in the UK: costs and outcomes

The aim of this study was to estimate the patterns of care and annual levels of health care resource use attributable to managing diabetic foot ulcers (DFUs) in clinical practice by the UK's National Health Service (NHS), and the associated costs of patient management. This was a retrospective cohort analysis of the records of 130 patients with a newly diagnosed DFU in The Health Improvement Network (THIN) database. Patients' characteristics, wound-related health outcomes and health care resource use were quantified, and the total NHS cost of patient management was estimated at 2015-2016 prices. Patients were predominantly managed in the community by nurses, with minimal clinical involvement of specialist physicians. 5% of patients saw a podiatrist, and 5% received a pressure-offloading device. Additionally, 17% of patients had at least one amputation within the first 12 months from initial presentation of their DFU. 14% of DFUs were documented as being clinically infected at initial presentation, although an additional 31% of patients were prescribed an antimicrobial dressing at the time of presentation. Of all the DFUs, 35% healed within 12 months, and the mean time to healing was 4·4 months. Over the study period, 48% of all patients received at least one prescription for a compression system, but significantly more patients healed if they never received compression (67% versus 16%; P < 0·001). The mean NHS cost of wound care over 12 months was an estimated £7800 per DFU (of which 13% was attributable to amputations), ranging from £2140 to £8800 per healed and unhealed DFU, respectively, and £16 900 per amputated wound. Consolidated medical records from a primary care held database provided 'real-world evidence' highlighting the consequences of inefficient and inadequate management of DFUs in clinical practice in the UK. Clinical and economic benefits to both patients and the NHS could accrue from strategies that focus on (i) wound prevention, (ii) improving wound-healing rates and (iii) reducing infection and amputation rates.

Risk factors for amputation in patients with diabetic foot infection: a prospective study

There is a variety of diagnostic and therapeutic algorithms for diabetic foot infections (DFIs). Some of them are too difficult to be applied in routine clinical approach. In the routine clinical approach, it is necessary to find new risk factors and end up with a quick and easy assessment of DFIs. In this study, we aimed to evaluate the independent risk factors for osteomyelitis, amputation and major amputation in patients with DFI using standard scoring procedures. We prospectively studied 379 patients with DFI. The variables were analysed using logistic analysis. A total of 126 cases (33·2%) underwent amputation. The odds ratios in the amputation model were 3·09 for osteomyelitis (P < 0·001), 4·90 for arterial stenosis (AS) (P < 0·001), 3·67 for the history of DFI (P = 0·001), 2·47 for ulcer duration >60 days (P = 0·001), 3·10 for ulcer depth > 15 mm (P < 0·001) and 10·28 for fungal DFI (P = 0·015). In this study, the unusual result of well-known literature was fungal DFI as an independent risk factor for amputation in patients with DFI.

Preliminary Evaluation of a Cycling Cleat Designed for Diabetic Foot Ulcers

BACKGROUND

Offloading devices for diabetic foot ulcers (DFU) generally restrict exercise. In addition to traditional health benefits, exercise could benefit DFU by increasing blood flow and acting as thermotherapy. This study functionally evaluated a cycling cleat designed for forefoot DFU.

METHODS

Fifteen individuals at risk of developing a DFU used a recumbent stationary bicycle to complete one 5-minute cycling bout with the DFU cleat on their study foot and one 5-minute bout without it. Foot stress was evaluated by plantar pressure insoles during cycling. Laser Doppler perfusion monitored blood flow to the hallux. Infrared photographs measured foot temperature before and after each cycling bout.

RESULTS

The specialized cleat significantly reduced forefoot plantar pressure (9.9 kPa versus 62.6 kPa, P < .05) and pressure time integral (15.4 versus 76.4 kPa*sec, P < .05). Irrespective of footwear condition, perfusion to the hallux increased (3.97 ± 1.2 versus 6.9 ± 1.4 tissue perfusion units, P < .05) after exercise. Infrared images revealed no changes in foot temperature.

CONCLUSIONS

The specialized cleat allowed participants to exercise with minimal forefoot stress. The observed increase in perfusion suggests that healing might improve if patients with active DFU were to use the cleat. Potential thermotherapy for DFU was not supported by this study. Evaluation of the device among individuals with active DFU is now warranted.

pH and Glucose Dual-Responsive Injectable Hydrogels with Insulin and Fibroblasts as Bioactive Dressings for Diabetic Wound Healing

pH and glucose dual-responsive injectable hydrogels were prepared through the cross-linking of Schiff's base and phenylboronate ester using phenylboronic-modified chitosan, poly(vinyl alcohol) and benzaldehyde-capped poly(ethylene glycol). Protein drugs and live cells could be incorporated into the hydrogels during the in situ cross-linking, displaying sustained and pH/glucose-triggered drug release from the hydrogels and cell viability and proliferation in the three-dimensional hydrogel matrix as well. Hence, the hydrogels with insulin and fibroblasts were considered as bioactive dressings for diabetic wound healing. A streptozotocin-induced diabetic rat model was used to evaluate the efficacy of hydrogel dressings in wound repair. The results revealed that the incorporation of insulin and L929 in the hydrogels could promote neovascularization and collagen deposition and enhance the wound-healing process of diabetic wounds. Thus, the drug- and cell-loaded hydrogels have promising potential in wound healing as a medicated system for various therapeutic proteins and live cells.

Relationship between hyperbaric oxygen therapy and quality of life in participants with chronic diabetic foot ulcers: data from a randomized controlled trial

AIMS

To investigate the effect of hyperbaric oxygen therapy on health-related quality of life (HRQoL) in participants with diabetes and chronic foot ulcers.

METHODS

Using data from a randomized controlled trial, we included 103 participants (49 in hyperbaric oxygen therapy group and 54 in sham group) for analyses. The primary outcome was HRQoL as measured by the EQ-5D-3L instrument, while secondary outcomes included quality of life evaluated by the Short Form 36 (SF-36) and Diabetic Foot Ulcers Scale-Short Form (DFS-SF). We used the analysis of covariance to assess whether the EQ-5D index values in hyperbaric oxygen therapy group differed from the sham group. Logistic regression was used to assess the relationship between hyperbaric oxygen therapy and the responses of 'problems' for the EQ-5D health states.

RESULTS

No significant differences in EQ-5D index values were found between the hyperbaric oxygen therapy and sham groups: 0.01 (95% CI -0.25, 0.28; p = 0.93) at week 12; 0.07 (95% CI -0.21, 0.34; p = 0.64) at week 6. Hyperbaric oxygen therapy was found to be associated with fewer participants reporting 'problems' in mobility (OR 0.24, 95% CI 0.07, 0.85 at week 12) and pain or discomfort (OR 0.20, 95% CI 0.07, 0.61 at week 6; OR 0.32, 95% CI 0.11, 0.97 at week 12), compared with the sham group. No significant differences in SF-36 or DFS-SF were observed.

CONCLUSIONS

No significant effect of hyperbaric oxygen therapy on HRQoL measured by EQ-5D index value was found in this study. Due to the potential insufficient power to assess statistical difference, more large-scale research is needed to further evaluate the effect of hyperbaric oxygen therapy on HRQoL in participants with chronic diabetic foot ulcers.

Monitoring Location-Specific Physical Activity via Integration of Accelerometry and Geotechnology Within Patients With or At Risk of Diabetic Foot Ulcers: A Technological Report

OBJECTIVE

Physical activity variability is a risk factor for diabetic foot ulcers (DFU). Geographic context may influence variability. This study developed initial methods for monitoring location-specific physical activity in this population. Secondarily, preliminary comparisons in location-specific physical activity were made between patients at risk versus patients with active DFU.

METHODS

Five at-risk and 5 actively ulcerated patients were monitored continuously for 72 hours with physical activity and GPS monitors. A custom algorithm time synchronized the 2 devices' data.

RESULTS

On average for all 10 subjects, 1.5 ± 2.1% of activity lacked a corresponding GPS location. 80 ± 11% of self-reported activity events per subject had a GPS identified location. The GPS identified locations were in agreement with the self-reported locations 98 ± 6% of the time. DFU participants' weight-bearing activity was 188% higher at home than away from home. At-risk participants showed similar weight-bearing activity at home as active DFU participants, however, at-risk participants had 132% more weight-bearing activity away-from-home.

CONCLUSIONS

Objectively monitoring location-specific physical activity proved feasible. Future studies using such methodology may enhance understanding of pathomechanics and treatment of DFU.