Causes, prevention, and management of diabetes-related foot ulcers.

In this Review, we aim to complement the 2023 update of the guidelines of the International Working Group on the Diabetic Foot. We highlight the complexity of the pathological processes that underlie diabetes-related foot ulceration (DFU) and draw attention to the potential implications for clinical management and outcome. Variation observed in the incidence and outcome of DFUs in different communities might result from differences in study populations and the accessibility of care. Comparing differences in incidence, management, and outcome of DFUs in different communities is an essential component of the quality of disease care. Additionally, these comparisons can also highlight the relationship between DFU incidence, management, and outcome and the structure of local clinical services and the availability of staff with the necessary skills. The clinical outcome is, however, also dependent on the availability of multidisciplinary care and the ability of people with DFUs to gain access to that care.

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

BACKGROUND: It is critical that interventions used to enhance the healing of chronic foot ulcers in diabetes are backed by high-quality evidence and cost-effectiveness. In previous years, the systematic review accompanying guidelines published by the International Working Group of the Diabetic Foot performed 4-yearly updates of previous searches, including trials of prospective, cross-sectional and case-control design. AIMS: Due to a need to re-evaluate older studies against newer standards of reporting and assessment of risk of bias, we performed a whole new search from conception, but limiting studies to randomised control trials only. MATERIALS AND METHODS: For this systematic review, we searched PubMed, Scopus and Web of Science databases for published studies on randomised control trials of interventions to enhance healing of diabetes-related foot ulcers. We only included trials comparing interventions to standard of care. Two independent reviewers selected articles for inclusion and assessed relevant outcomes as well as methodological quality. RESULTS: The literature search identified 22,250 articles, of which 262 were selected for full text review across 10 categories of interventions. Overall, the certainty of evidence for a majority of wound healing interventions was low or very low, with moderate evidence existing for two interventions (sucrose-octasulfate and leucocyte, platelet and fibrin patch) and low quality evidence for a further four (hyperbaric oxygen, topical oxygen, placental derived products and negative pressure wound therapy). The majority of interventions had insufficient evidence. CONCLUSION: Overall, the evidence to support any other intervention to enhance wound healing is lacking and further high-quality randomised control trials are encouraged.

Guidelines on the classification of foot ulcers in people with diabetes (IWGDF 2023 update).

BACKGROUND: This publication represents a scheduled update of the 2019 guidelines of the International Working Group of the Diabetic Foot (IWGDF) addressing the use of systems to classify foot ulcers in people with diabetes in routine clinical practice. The guidelines are based on a systematic review of the available literature that identified 28 classifications addressed in 149 articles and, subsequently, expert opinion using the GRADE methodology. METHODS: First, we have developed a list of classification systems considered as being potentially adequate for use in a clinical setting, through the summary of judgements for diagnostic tests, focussing on the usability, accuracy and reliability of each system to predict ulcer-related complications as well as use of resources. Second, we have determined, following group debate and consensus, which of them should be used in specific clinical scenarios. Following this process, in a person with diabetes and a foot ulcer we recommend: (a) for communication among healthcare professionals: to use the SINBAD (Site, Ischaemia, Bacterial infection, Area and Depth) system (first option) or consider using WIfI (Wound, Ischaemia, foot Infection) system (alternative option, when the required equipment and level of expertise is available and it is considered feasible) and in each case the individual variables that compose the systems should be described rather than a total score; (b) for predicting the outcome of an ulcer in a specific individual: no existing system could be recommended; (c) for characterising a person with an infected ulcer: the use of the IDSA/IWGDF classification (first option) or consider using the WIfI system (alternative option, when the required equipment and level of expertise is available and it is considered as feasible); (d) for characterising a person with peripheral artery disease: consider using the WIfI system as a means to stratify healing likelihood and amputation risk; (e) for the audit of outcome(s) of populations: the use of the SINBAD score. CONCLUSIONS: For all recommendations made using GRADE, the certainty of evidence was judged, at best, as being low. Nevertheless, based on the rational application of current data this approach allowed the proposal of recommendations, which are likely to have clinical utility.

The value of loss of protective pain sensation in predicting a first ulceration of the foot in people with diabetes.

AIM: To determine both the risk of first ever ulcer (FEU) and its time to onset in a population which had loss of protective sensation (LOPS) in the foot either with or without loss of protective pain (LOPP). METHODS: People with diabetes and LOPS without history of FEU presenting in a specialist clinic were included. LOPP was diagnosed by reduced vibration perception and pain perception by using a pinprick simulator. Participants were followed by routine foot checks, phone interview or by letter until the occurrence of a FEU, death or the end of observation period. Survival functions in LOPP strata were compared by log rank test. The hazard ratio (HR) of an FEU in people with compared to people without LOPP was estimated using Cox regression. Time to first ulcer was estimated using the framework of an accelerated failure time (AFT) model. RESULTS: One hundred and thirty participants were followed up for a median of 48.3 months. Pain perception was lost in 55.4%. Eighteen people with LOPP developed a FEU (25.0%) as opposed to six (10.3%) of those with no LOPP (p = 0.02). Age-sex-adjusted HR for FEU was 3.0 (p = 0.02) for people with compared to people without LOPP. Age-sex-adjusted time to FEU for people with LOPP was approximately half (p = 0.03) than people without LOPP. CONCLUSIONS: It is suggested that estimation of LOPP is included in routine practice because of its high predictive value for a FEU.

Classification of foot ulcers in people with diabetes: A systematic review.

BACKGROUND: Classification and scoring systems can help both clinical management and audit the outcomes of routine care. AIM: This study aimed to assess published systems used to characterise ulcers in people with diabetes to determine which should be recommended to (a) aid communication between health professionals, (b) predict clinical outcome of individual ulcers, (c) characterise people with infection and/or peripheral arterial disease, and (d) audit to compare outcomes in different populations. This systematic review is part of the process of developing the 2023 guidelines to classify foot ulcers from the International Working Group on Diabetic Foot. METHODS: We searched PubMed, Scopus and Web of Science for articles published up to December 2021 which evaluated the association, accuracy or reliability of systems used to classify ulcers in people with diabetes. Published classifications had to have been validated in populations of >80% of people with diabetes and a foot ulcer. RESULTS: We found 28 systems addressed in 149 studies. Overall, the certainty of the evidence for each classification was low or very low, with 19 (68%) of the classifications being assessed by ≤ 3 studies. The most frequently validated system was the one from Meggitt-Wagner, but the articles validating this system focused mainly on the association between the different grades and amputation. Clinical outcomes were not standardized but included ulcer-free survival, ulcer healing, hospitalisation, limb amputation, mortality, and cost. CONCLUSION: Despite the limitations, this systematic review provided sufficient evidence to support recommendations on the use of six particular systems in specific clinical scenarios.

Guidelines on interventions to enhance healing of foot ulcers in people with diabetes (IWGDF 2023 update).

AIMS: Principles of wound management, including debridement, wound bed preparation, and newer technologies involving alternation of wound physiology to facilitate healing, are of utmost importance when attempting to heal a chronic diabetes-related foot ulcer. However, the rising incidence and costs of diabetes-related foot ulcer management necessitate that interventions to enhance wound healing of chronic diabetes-related foot ulcers are supported by high-quality evidence of efficacy and cost effectiveness when used in conjunction with established aspects of gold-standard multidisciplinary care. This is the 2023 International Working Group on the Diabetic Foot (IWGDF) evidence-based guideline on wound healing interventions to promote healing of foot ulcers in persons with diabetes. It serves as an update of the 2019 IWGDF guideline. MATERIALS AND METHODS: We followed the GRADE approach by devising clinical questions and important outcomes in the Patient-Intervention-Control-Outcome (PICO) format, undertaking a systematic review, developing summary of judgements tables, and writing recommendations and rationale for each question. Each recommendation is based on the evidence found in the systematic review and, using the GRADE summary of judgement items, including desirable and undesirable effects, certainty of evidence, patient values, resources required, cost effectiveness, equity, feasibility, and acceptability, we formulated recommendations that were agreed by the authors and reviewed by independent experts and stakeholders. RESULTS: From the results of the systematic review and evidence-to-decision making process, we were able to make 29 separate recommendations. We made a number of conditional supportive recommendations for the use of interventions to improve healing of foot ulcers in people with diabetes. These include the use of sucrose octasulfate dressings, the use of negative pressure wound therapies for post-operative wounds, the use of placental-derived products, the use of the autologous leucocyte/platelet/fibrin patch, the use of topical oxygen therapy, and the use of hyperbaric oxygen. Although in all cases it was stressed that these should be used where best standard of care was not able to heal the wound alone and where resources were available for the interventions. CONCLUSIONS: These wound healing recommendations should support improved outcomes for people with diabetes and ulcers of the foot, and we hope that widescale implementation will follow. However, although the certainty of much of the evidence on which to base the recommendations is improving, it remains poor overall. We encourage not more, but better quality trials including those with a health economic analysis, into this area.

Impact of case-mix adjustment on observed variation in the healing of diabetic foot ulcers at 12 weeks using data from the National Diabetes Foot Care Audit of England and Wales: A cohort study.

AIM: This cohort study investigates the extent to which variation in ulcer healing between services can be explained by demographic and clinical characteristics. METHODS: The National Diabetes Foot Care Audit collated data on people with diabetic foot ulcers presenting to specialist services in England and Wales between July 2014 and March 2018. Logistic regression models were created to describe associations between risk factors and a person being alive and ulcer-free 12 weeks from presentation, and to investigate whether variation between 120 participating services persisted after risk factor adjustment. RESULTS: Of 27,030 people with valid outcome data, 12,925 (47.8%) were alive and ulcer-free at 12 weeks, 13,745 (50.9%) had an unhealed ulcer and 360 had died (1.3%). Factors associated with worse outcome were male sex, more severe ulcers, history of cardiac or renal disease and a longer time between first presentation to a non-specialist healthcare professional and first expert assessment. After adjustment for these factors, four services (3.3%) were more than 3SD above and seven services (5.8%) were more than 3SD below the national mean for proportions that were alive and ulcer-free at follow-up. CONCLUSIONS/INTERPRETATIONS: Variation in the healing of diabetic foot ulcers between specialist services in England and Wales persisted after adjusting for demographic characteristics, ulcer severity, smoking, body mass index and co-morbidities. We conclude that other factors contribute to variation in healing of diabetic foot ulcers and include the time to specialist assessment.

The Charcot Foot Reflects a Response to Injury That Is Critically Distorted by Preexisting Nerve Damage: An Imperfect Storm.

It has been recognized since comprehensive descriptions by Jean-Martin Charcot in 1868 and 1883 that development of what is usually known as neuropathic osteoarthropathy (or the Charcot foot) requires the coincidence of neuropathy and inflammation. Despite this, detailed understanding of the causes has remained remarkably limited in the succeeding century and a half. The aim of this descriptive account is to draw particular attention to the processes involved in both the onset and resolution of the inflammation that is an essential component of active disease. The principal observation is that while neuropathy is common in people with diabetes, the inflammation and secondary skeletal damage that characterize neuropathic osteoarthropathy are observed in only a small minority of people with diabetes and with neuropathy. We therefore argue that the key to understanding the causes of the Charcot foot is to focus equally on those who have active disease as well as those who do not. Although neuropathy is essential for development of the disorder, neuropathy also has an adverse impact on the mechanisms involved in the onset of inflammation, and these may be critically affected in the majority of those who are susceptible. The Charcot foot is uncommon in people with diabetes (or any other cause of neuropathy) because the large majority of those with neuropathy may have also lost the capacity to mount the specific inflammatory reaction that is essential for its development.

Guidelines on the classification of diabetic foot ulcers (IWGDF 2019).

The International Working Group on the Diabetic Foot (IWGDF) has been publishing evidence-based guidelines on the prevention and management of diabetic foot disease since 1999. This publication represents a new guideline addressing the use of classifications of diabetic foot ulcers in routine clinical practice and reviews those which have been published. We only consider systems of classification used for active diabetic foot ulcers and do not include those that might be used to define risk of future ulceration. The guidelines are based on a review of the available literature and on expert opinion leading to the identification of eight key factors judged to contribute most to clinical outcomes. Classifications are graded on the number of key factors included as well as on internal and external validation and the use for which a classification is intended. Key factors judged to contribute to the scoring of classifications are of three types: patient related (end-stage renal failure), limb-related (peripheral artery disease and loss of protective sensation), and ulcer-related (area, depth, site, single, or multiple and infection). Particular systems considered for each of the following five clinical situations: (a) communication among health professionals, (b) predicting the outcome of an individual ulcer, (c) as an aid to clinical decision-making for an individual case, (d) assessment of a wound, with/without infection, and peripheral artery disease (assessment of perfusion and potential benefit from revascularisation), and (d) audit of outcome in local, regional, or national populations. We recommend: (a) for communication among health professionals the use of the SINBAD system (that includes Site, Ischaemia, Neuropathy, Bacterial Infection and Depth); (b) no existing classification for predicting outcome of an individual ulcer; (c) the Infectious Diseases Society of America/IWGDF (IDSA/IWGDF) classification for assessment of infection; (d) the WIfI (Wound, Ischemia, and foot Infection) system for the assessment of perfusion and the likely benefit of revascularisation; and (e) the SINBAD classification for the audit of outcome of populations.

Diabetic foot ulcer classifications: A critical review.

Classification and scoring systems can help both clinical management and audit outcomes of routine care. The aim of this study was to assess published systems of diabetic foot ulcers (DFUs) to determine which should be recommended for a given clinical purpose. Published classifications had to have been validated in populations of > 75% people with diabetes and a foot ulcer. Each study was assessed for internal and external validity and reliability. Eight key factors associated with failure to heal were identified from large clinical series and each classification was scored on the number of these key factors included. Classifications were then arranged according to their proposed purpose into one or more of four groups: (a) aid communication between health professionals, (b) predict clinical outcome of individual ulcers, (c) aid clinical management decision making for an individual case, and (d) audit to compare outcome in different populations. Thirty-seven classification systems were identified of which 18 were excluded for not being validated in a population of >75% DFUs. The included 19 classifications had different purposes and were derived from different populations. Only six were developed in multicentre studies, just 13 were externally validated, and very few had evaluated reliability.Classifications varied in the number (4 - 30), and definition of individual items and the diagnostic tools required. Clinical outcomes were not standardized but included ulcer-free survival, ulcer healing, hospitalization, limb amputation, mortality, and cost. Despite the limitations, there was sufficient evidence to make recommendations on the use of particular classifications for the indications listed above.

Rat bite as a cause of diabetic foot ulcer in sub-Saharan Africa.

There have been relatively few reports of foot ulcers in diabetes resulting from rat bite. The findings were derived from people attending a single specialist service in Dar es Salaam for diabetic foot ulcers (DFUs) between 1 January 1999 and 31 December 2016. Details from people presenting for the first time with an ulcer judged to be caused by rat bite were compared with those with from other causes of foot ulcer. There were 426 first recorded foot ulcer episodes (in 179 people) judged to be caused by rat bite. The affected population was significantly younger (mean 55.9 vs 57.5 years, P = .037) and had a lower body mass index (26.5 vs 27.9, P = .008) than controls with other types of foot ulcer. They also presented significantly sooner (7.8 vs 18.2 days, P < .001) and were more likely to heal (85.8 vs 5.5%, P < .001), even though there was also a trend towards an increased risk of death (9.1% vs 5.3%, P = .032). Rat bite is an uncommon cause of DFU, but is not rare. Although the incidence of ulcer healing is higher than in a general foot ulcer population, the incidence of death is also higher.

Which diagnostic tests in everyday clinical practice are (not) useful in the management of diabetic foot disease?

This commentary reviews the use of a small number of tests used in the routine management of foot disease in diabetes. The aim is to consider some of the evidence underlying the use of these tests and the difficulties that can be encountered in interpretation. All tests have their limitations and it is important for these to be understood by the clinicians who request them. There are few test results which are categorically diagnostic in the field of the diabetic foot and the majority merely provide supporting evidence for a diagnosis that is either less or more strongly suspected on other grounds.

Examining diabetic heel ulcers through an ecological lens: microbial community dynamics associated with healing and infection.

PURPOSE: While some micro-organisms, such as Staphylococcus aureus, are clearly implicated in causing tissue damage in diabetic foot ulcers (DFUs), our knowledge of the contribution of the entire microbiome to clinical outcomes is limited. We profiled the microbiome of a longitudinal sample series of 28 people with diabetes and DFUs of the heel in an attempt to better characterize the relationship between healing, infection and the microbiome. METHODOLOGY: In total, 237 samples were analysed from 28 DFUs, collected at fortnightly intervals for 6 months or until healing. Microbiome profiles were generated by 16S rRNA gene sequence analysis, supplemented by targeted nanopore sequencing.Result/Key findings. DFUs which failed to heal during the study period (20/28, 71.4 %) were more likely to be persistently colonized with a heterogeneous community of micro-organisms including anaerobes and Enterobacteriaceae (log-likelihood ratio 9.56, P=0.008). During clinically apparent infection, a reduction in the diversity of micro-organisms in a DFU was often observed due to expansion of one or two taxa, with recovery in diversity at resolution. Modelling of the predicted species interactions in a single DFU with high diversity indicated that networks of metabolic interactions may exist that contribute to the formation of stable communities. CONCLUSION: Longitudinal profiling is an essential tool for improving our understanding of the microbiology of chronic wounds, as community dynamics associated with clinical events can only be identified by examining changes over multiple time points. The development of complex communities, particularly involving Enterobacteriaceae and strict anaerobes, may be contributing to poor outcomes in DFUs and requires further investigation.

LeucoPatch system for the management of hard-to-heal diabetic foot ulcers in the UK, Denmark, and Sweden: an observer-masked, randomised controlled trial.

BACKGROUND: The LeucoPatch device uses bedside centrifugation without additional reagents to generate a disc comprising autologous leucocytes, platelets, and fibrin, which is applied to the surface of the wound. We aimed to test the effectiveness of LeucoPatch on the healing of hard-to-heal foot ulcers in people with diabetes. METHODS: This was a multicentre, international, observer-masked, randomised controlled trial of people with diabetes and a hard-to-heal foot ulcer done in 32 specialist diabetic foot clinics in three countries (UK, Denmark, and Sweden). After a 4-week run-in period, those with a reduction in ulcer area of less than 50% were randomly allocated (1:1) by computer-generated, web-based randomisation (block sizes of two, four, and six) to either prespecified good standard care alone or care plus weekly application of LeucoPatch. The primary outcome was the proportion of ulcers that healed within 20 weeks assessed in the intention-to-treat population (all participants with post-randomisation data collected), defined as complete epithelialisation (confirmed by an observer who was masked to randomisation group), and remained healed for 4 weeks. This trial is registered with the ISRCTN registry, number 27665670, and ClinicalTrials.gov, number NCT02224742. FINDINGS: Between Aug 30, 2013, and May 3, 2017, 269 participants were randomly allocated to receive treatment (137 to receive standard care and 132 to receive LeucoPatch). The mean age was 61·9 years (SD 11·6), 217 (82%) were men, and 222 (83%) had type 2 diabetes. In the LeucoPatch group, 45 (34%) of 132 ulcers healed within 20 weeks versus 29 (22%) of 134 ulcers in the standard care group (odds ratio 1·58, 96% CI 1·04-2·40; p=0·0235) by intention-to-treat analysis. Time to healing was shorter in the LeucoPatch group (p=0·0246) than in the standard care group. No difference in adverse events was seen between the groups. The most common serious adverse event (SAE) was diabetic foot infection (24 events in the LeucoPatch group [24% of all SAEs] and 20 in the standard care group [27% of all SAEs]. There were no device-related adverse events. INTERPRETATION: The use of LeucoPatch is associated with significant enhancement of healing of hard-to-heal foot ulcers in people with diabetes. FUNDING: Reapplix ApS.

Amputation-free survival in 17,353 people at high risk for foot ulceration in diabetes: a national observational study.

AIMS/HYPOTHESIS: Our aim was to investigate amputation-free survival in people at high risk for foot ulceration in diabetes ('high-risk foot'), and to compare different subcategories of high-risk foot. METHODS: Overall, 17,353 people with diabetes and high-risk foot from January 2008 to December 2011 were identified from the Scotland-wide diabetes register (Scottish Care Information-Diabetes: N = 247,278). Participants were followed-up for up to 2 years from baseline and were categorised into three groups: (1) those with no previous ulcer, (2) those with an active ulcer or (3) those with a healed previous ulcer. Participants with prior minor or major amputation were excluded. Accelerated failure time models were used to compare amputation-free survival up to 2 years between the three exposure groups. RESULTS: The 2 year amputation-free survival rate in all people with diabetes with high-risk foot was 84.5%. In this study group, 270 people (10.0%) had an amputation and 2424 (90.0%) died during the 2 year follow-up period. People who had active and healed previous ulcers at baseline had significantly lower 2 year amputation-free survival compared with those who had no previous ulcer (both p < 0.0001). The percentage of people who died within 2 years for those with healed ulcer, active ulcer or no baseline ulcer was 22.8%, 16% and 12.1%, respectively. CONCLUSIONS/INTERPRETATION: In people judged to be at high risk of foot ulceration, the risk of death was up to nine times the risk of amputation. Death rates were higher for people with diabetes who had healed ulcers than for those with active ulcers. However, people with active ulcers had the highest risk of amputation.

Current Challenges and Opportunities in the Prevention and Management of Diabetic Foot Ulcers.

Diabetic foot ulcers remain a major health care problem. They are common, result in considerable suffering, frequently recur, and are associated with high mortality, as well as considerable health care costs. While national and international guidance exists, the evidence base for much of routine clinical care is thin. It follows that many aspects of the structure and delivery of care are susceptible to the beliefs and opinion of individuals. It is probable that this contributes to the geographic variation in outcome that has been documented in a number of countries. This article considers these issues in depth and emphasizes the urgent need to improve the design and conduct of clinical trials in this field, as well as to undertake systematic comparison of the results of routine care in different health economies. There is strong suggestive evidence to indicate that appropriate changes in the relevant care pathways can result in a prompt improvement in clinical outcomes.

The LeucoPatch® system in the management of hard-to-heal diabetic foot ulcers: study protocol for a randomised controlled trial.

BACKGROUND: Diabetic foot ulcers are a common and severe complication of diabetes mellitus. Standard treatment includes debridement, offloading, management of infection and revascularisation where appropriate, although healing times may be long. The LeucoPatch® device is used to generate an autologous platelet-rich fibrin and leucocyte wound dressing produced from the patient's own venous blood by centrifugation, but without the addition of any reagents. The final product comprises a thin, circular patch composed predominantly of fibrin together with living platelets and leucocytes. Promising results have been obtained in non-controlled studies this system, but this now needs to be tested in a randomised controlled trial (RCT). If confirmed, the LeucoPatch® may become an important new tool in the armamentarium in the management of diabetic foot ulcers which are hard-to-heal. METHODS: People with diabetes and hard-to-heal ulcers of the foot will receive either pre-specified good standard care or good standard care supplemented by the application of the LeucoPatch® device. The primary outcome will be the percentage of ulcers healed within 20 weeks. Healing will be defined as complete epithelialisation without discharge that is maintained for 4 weeks and is confirmed by an observer blind to randomisation group. DISCUSSION: Ulcers of the foot are a major source of morbidity to patients with diabetes and costs to health care economies. The study population is designed to be as inclusive as possible with the aim of maximising the external validity of any findings. The primary outcome measure is healing within 20 weeks of randomisation and the trial also includes a number of secondary outcome measures. Among these are rate of change in ulcer area as a predictor of the likelihood of eventual healing, minor and major amputation of the target limb, the incidence of infection and quality of life. TRIAL REGISTRATION: International Standard Randomised Controlled Trial, ISRCTN27665670 . Registered on 5 July 2013.