Diabetic foot infections: current concept review

Development and validation of a new questionnaire for the assessment of patients with diabetic foot disease: The Diabetic Foot Questionnaire (DiaFootQ)

BACKGROUND

The epidemiology data and global burden of diabetic foot disease underscores the need for effective prevention strategies, which requires an early diagnosis. Patient-reported outcome measures are instruments based on a simple format, which favours their application. Currently, there is an absence of instruments with a broad enough scope to capture the diverse aspects involved in diabetic foot disease.

OBJECTIVES

To develop a questionnaire for the assessment of patients with diabetic foot disease and carry out an analysis of its validity and reliability.

METHODS

The study was developed in two stages. Stage 1: the Delphi Panel was composed of 22 experts. The questionnaire is made up of 25 questions selected, after three rounds, from an initial sample of 68 questions. Stage 2: A validation study was performed. With a sample of 273 subjects, an exploratory factor analysis and an analysis of internal consistency, items response, and validity were carried out using the Diabetes Quality of Life, SF-12v2, Foot Function Index and EuroQol EQ5D questionnaires. Measurements of error and sensitivity to change were also analyzed.

RESULTS

A 25-item questionnaire (DiaFootQ) was developed. It comprised two dimensions: 1) lifestyle and function; and 2) footwear and foot self-care. Sample (n=273) mean age was 69.77 years (±11.08). The internal consistency of DiafootQ was α=0.916, and item response values were ICC=0.862-0.998. External validity correlation levels ranged from r=0.386 to r=0.888.

CONCLUSION

DiaFootQ was developed. Integrating the main aspects involved in diabetic foot disease could help to detect more accurately the risk or severity of these patients. DiaFootQ is a well-structured, valid, and reliable tool whose use should be promoted in clinical and research settings.

Nanozymes for the Therapeutic Treatment of Diabetic Foot Ulcers

Diabetic foot ulcers (DFU) are chronic, refractory wounds caused by diabetic neuropathy, vascular disease, and bacterial infection, and have become one of the most serious and persistent complications of diabetes mellitus because of their high incidence and difficulty in healing. Its malignancy results from a complex microenvironment that includes a series of unfriendly physiological states secondary to hyperglycemia, such as recurrent infections, excessive oxidative stress, persistent inflammation, and ischemia and hypoxia. However, current common clinical treatments, such as antibiotic therapy, insulin therapy, surgical debridement, and conventional wound dressings all have drawbacks, and suboptimal outcomes exacerbate the financial and physical burdens of diabetic patients. Therefore, development of new, effective and affordable treatments for DFU represents a top priority to improve the quality of life of diabetic patients. In recent years, nanozymes-based diabetic wound therapy systems have been attracting extensive interest by integrating the unique advantages of nanomaterials and natural enzymes. Compared with natural enzymes, nanozymes possess more stable catalytic activity, lower production cost and greater maneuverability. Remarkably, many nanozymes possess multienzyme activities that can cascade multiple enzyme-catalyzed reactions simultaneously throughout the recovery process of DFU. Additionally, their favorable photothermal-acoustic properties can be exploited for further enhancement of the therapeutic effects. In this review we first describe the characteristic pathological microenvironment of DFU, then discuss the therapeutic mechanisms and applications of nanozymes in DFU healing, and finally, highlight the challenges and perspectives of nanozyme development for DFU treatment.

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.

Update of biomarkers to diagnose diabetic foot osteomyelitis: A meta-analysis and systematic review

The aim of this study was to evaluate the diagnostic characteristics of biomarker for diabetic foot osteomyelitis (DFO). We searched PubMed, Scopus, Embase and Medline for studies who report serological markers and DFO before December 2022. Studies must include at least one of the following diagnostic parameters for biomarkers: area under the curve, sensitivities, specificities, positive predictive value, negative predictive value. Two authors evaluated quality using the Quality Assessment of Diagnostic Accuracy Studies tool. We included 19 papers. In this systematic review, there were 2854 subjects with 2134 (74.8%) of those patients being included in the meta-analysis. The most common biomarkers were erythrocyte sedimentation rate (ESR), C-reactive protein (CRP) and procalcitonin (PCT). A meta-analysis was then performed where data were evaluated with Forrest plots and receiver operating characteristic curves. The pooled sensitivity and specificity were 0.72 and 0.75 for PCT, 0.72 and 0.76 for CRP and 0.70 and 0.77 for ESR. Pooled area under the curves for ESR, CRP and PCT were 0.83, 0.77 and 0.71, respectfully. Average diagnostic odds ratios were 16.1 (range 3.6-55.4), 14.3 (range 2.7-48.7) and 6.7 (range 3.6-10.4) for ESR, CRP and PCT, respectfully. None of the biomarkers we evaluated could be rated as 'outstanding' to diagnose osteomyelitis. Based on the areas under the curve, ESR is an 'excellent' biomarker to detect osteomyelitis, and CRP and PCT are 'acceptable' biomarkers to diagnose osteomyelitis. Diagnostic odds ratios indicate that ESR, CRP and PCT are 'good' or 'very good' tools to identify osteomyelitis.

Assessment between antiseptic and normal saline for negative pressure wound therapy with instillation and dwell time in diabetic foot infections

Negative pressure wound therapy with instillation and dwell time (NPWTi-d) is increasingly used for a diverse range of wounds. Meanwhile, the topical wound irrigation solution consisting of polyhexamethylene biguanide and betaine (PHMB-B) has shown efficacy in managing wound infections. However, the effectiveness of this solution as a topical instillation solution for NPWTi-d in patients with diabetic foot infections (DFIs) has not been thoroughly studied. The objective of this retrospective study was to evaluate the impact of using PHMB-B as the instillation solution during NPWTi-d on reducing bioburden and improving clinical outcomes in patients with DFIs. Between January 2017 and December 2022, a series of patients with DFIs received treatment with NPWTi-d, using either PHMB-B or normal saline as the instillation solution. Data collected retrospectively included demographic information, baseline wound characteristics, and treatment outcomes. The study included 61 patients in the PHMB-B group and 73 patients in the normal saline group, all diagnosed with DFIs. In comparison to patients treated with normal saline, patients with PHMB-B exhibited no significant differences in terms of wound bed preparation time (P = 0.5034), length of hospital stay (P = 0.6783), NPWTi-d application times (P = 0.1458), duration of systematic antimicrobial administration (P = 0.3567), or overall cost of hospitalization (P = 0.6713). The findings of the study suggest that the use of either PHMB-B or normal saline as an instillation solution in NPWTi-d for DFIs shows promise and effectiveness, yet no clinical distinction was observed between the two solutions.

Triglyceride-glucose index is strongly associated with all-cause mortality in elderly females with diabetic foot ulcers: A 9-year follow-up study

This study aims to explore the association between the triglyceride-glucose (TyG) index and all-cause mortality in patients with diabetic foot ulcers (DFUs) through an ambispective cohort study. A total of 555 inpatients with DFUs were qualified to participate in the trial study from 2013 to 2022. Throughout a median 63-month period, all subjects were followed up every 6 months. According to the three quantiles of the TyG index, participants were divided into three groups: low-level (≤8.75, n = 185), moderate-level (8.76-9.33, n = 185) and high-level (≥9.34, n = 185). The association between the TyG index and all-cause mortality in patients with DFUs was then assessed. During the follow-up period, out of 555 patients with DFUs, 116 died (20.9%). After adjusting for confounding factors, the TyG index was positively associated with all-cause mortality in patients with DFUs (HR = 1.733; 95% CI = 1.341-2.241; p < 0.001). Compared with the low-level TyG index, the moderate-level TyG index (HR = 1.685; 95% CI = 1.011-2.810; p = 0.045) and the high-level TyG index (HR = 2.769; 95% CI = 1.678-4.568; p < 0.001) were positively correlated with all-cause mortality in patients with DFUs. Additionally, in subgroup analysis, both females (HR = 1.905; 95% CI = 1.250-2.904; p = 0.003), males (HR = 1.729; 95% CI = 1.240-2.409; p = 0.001), younger (<65 years old) (HR = 1.467; 95% CI = 1.008-2.135; p = 0.046) and elderly (≥ 65) (HR = 1.933; 95% CI = 1.339-2.791; p < 0.001) showed a positive correlation between TyG index and all-cause mortality rate in patients with DFUs. Furthermore, in the high-level TyG index group compared, males (HR = 2.699; 95% CI = 1.457-4.998) and participants aged <65 years (HR = 2.031; 95% CI = 0.972-4.242), with the TyG index level increase by 1.0, the risk for all-cause mortality increased 3.277-fold in females (HR = 4.277; 95% CI = 1.645-11.124) and 1.909-fold in elderly aged ≥65 years (HR = 2.909; 95% CI = 1.486-5.695), respectively. Kaplan-Meier survival curve analysis showed that the higher the TyG index level, the higher risk of all-cause mortality in patients with DFUs (log-rank, all p < 0.001). Briefly, this study implies a strong positive correlation between the TyG index and all-cause mortality in patients with DFUs, especially in older women. Therefore, special attention should be paid to elderly females with DFUs because they have a higher TyG index level and risk of all-cause mortality than other populations in daily clinical practice.

Lipidomics Characterization of the Microbiome in People with Diabetic Foot Infection Using MALDI-TOF MS

Lipidomic profiling has emerged as a powerful tool for the comprehensive characterization of bacterial species, particularly in the context of clinical diagnostics. Utilizing matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS), this study aims to elucidate the lipidomic landscapes of bacterial strains isolated from diabetic foot infections (DFI). Our analysis successfully identified a diverse array of lipids in the cellular membranes of both Gram-positive and Gram-negative bacteria, revealing a total of 108 unique fatty acid combinations. Specifically, we identified 26 LPG, 33 LPE, 43 PE, 114 PG, 89 TAG, and 120 CLP in Gram-positive bacteria and 10 LPG, 14 LPE, 124 PE, 37 PG, 13 TAG, and 22 CLP in Gram-negative strains. Key fatty acids, such as palmitic acid, palmitoleic acid, stearic acid, and oleic acid, were prominently featured. Univariate analysis further highlighted distinct lipidomic signatures among the bacterial strains, revealing elevated levels of phosphatidylethanolamine (PE) and phosphatidylglycerol (PG) in Gram-negative bacteria associated with DFI. In contrast, Gram-positive strains demonstrated increased or uniquely fluctuating levels of triglyceride (TAG) and cardiolipin (CLP). These findings not only underscore the utility of MALDI-TOF MS in bacterial lipidomics but also provide valuable insights into the lipidomic adaptations of bacteria in diabetic foot infections, thereby laying the groundwork for future studies aimed at constructing microbial lipid libraries for enhanced bacterial identification.

Nasal MRSA carriage is a risk factor for development of antibiotic resistance in diabetic foot ulcers and is significantly higher than diabetic and non-diabetic individuals without foot ulcer

BACKGROUND

Diabetic foot ulcer (DFU) is a major complication of diabetes often impacted by polymicrobial infection in the wound site. Diabetic patients are immunocompromised in nature and hence vulnerable to infection once the skin barrier is breached. Microbiological culture-based methods show that Staphylococcus aureus (SA) is the most frequently isolated bacteria from the DFU wounds. SA and its most clinically important antibiotic resistant variant methicillin-resistant S. aureus (MRSA) are commonly found in the nasal vestibule and colonization of SA as well as MRSA in any wound site can aggravate the condition. We hypothesize that the presence of nasal MRSA carriage can serve as a potential risk factor contributing to the emergence of antibiotic resistance in diabetic foot ulcer wounds.

METHODS

In the present study, we have compared the carriage of SA and MRSA in nasal cavity and foot skin among DFU patients (D+F+, n = 50), diabetic patients without any ulcer (D+F-, n = 50), and healthy controls (D-F-, n = 40) by using bacterial culture and PCR based methods. The D+F+, D+F- and D-F-individuals were further categorized based on the presence or absence of MRSA and clinical parameters were compared between MRSA+ ve and MRSA-ve individuals in each of the three groups mentioned above.

RESULTS

Our results show that, (a) nasal MRSA carriage is significantly higher (p < 0.05) in D+F+ group than the D+F- and D-F- and significantly associated with wound MRSA carriage in D+ F+ individuals (O.R. = 4.09; 95% C.I. = 1.12-15.05) and (b) the HbA1C level is significantly higher (p < 0.02) in wound MRSA positive, compared to MRSA negative D+F+ patients. Interestingly more than half of the MRSA (64%) isolated from DFU wound were identified to be multidrug resistant.

CONCLUSION

These findings strongly suggest that nasal MRSA carriage can act as a risk factor for development of antibiotic resistance in diabetic foot ulcers and it is therefore important to screen nasal and wound sites of these patients regularly. We have also developed a rapid multiplex PCR assay to detect MRSA from clinical isolates or microbial DNA isolated from clinical samples in the hospital settings.

Complementary Gene Therapy after Revascularization with the Saphenous Vein in Diabetic Foot Syndrome

Diabetic foot syndrome (DFS) is one of the most serious macroangiopathic complications of diabetes. The primary treatment option is revascularization, but complementary therapies are still being sought. The study group consisted of 18 patients diagnosed with ischemic ulcerative and necrotic lesions in DFS. Patients underwent revascularization procedures and, due to unsatisfactory healing of the lesions, were randomly allocated to two groups: a group in which bicistronic VEGF165/HGF plasmid was administered and a control group in which saline placebo was administered. Before gene therapy administration and after 7, 30, 90, and 180 days, color duplex ultrasonography (CDU) was performed, the ankle-brachial index (ABI) and transcutaneous oxygen pressure (TcPO2) were measured, and DFS changes were described and documented photographically. In the gene therapy group, four out of eight patients (50%) healed their DFS lesions before 12 weeks. During this time, the ABI increased by an average of 0.25 and TcPO2 by 30.4 mmHg. In the control group, healing of the lesions by week 12 occurred in six out of nine patients (66.67%), and the ABI increased by an average of 0.14 and TcPO2 by 27.1 mmHg. One major amputation occurred in each group. Gene therapy may be an attractive option for complementary treatment in DFS.

Quantitative Imaging of the Action of vCPP2319, an Antimicrobial Peptide from a Viral Scaffold, against Staphylococcus aureus Biofilms of a Clinical Isolate

The formation of biofilms is a common virulence factor that makes bacterial infections difficult to treat and a major human health problem. Biofilms are bacterial communities embedded in a self-produced matrix of extracellular polymeric substances (EPS). In this work, we show that vCPP2319, a polycationic peptide derived from the capsid protein of Torque teno douroucouli virus, is active against preformed Staphylococcus aureus biofilms produced by both a reference strain and a clinical strain isolated from a diabetic foot infection, mainly by the killing of biofilm-embedded bacteria. The direct effect of vCPP2319 on bacterial cells was imaged using atomic force and confocal laser scanning microscopy, showing that the peptide induces morphological changes in bacterial cells and membrane disruption. Importantly, vCPP2319 exhibits low toxicity toward human cells and high stability in human serum. Since vCPP2319 has a limited effect on the biofilm EPS matrix itself, we explored a combined effect with α-amylase (EC 3.2.1.1), an EPS matrix-degrading enzyme. In fact, α-amylase decreases the density of S. aureus biofilms by 2.5-fold. Nonetheless, quantitative analysis of bioimaging data shows that vCPP2319 partially restores biofilm compactness after digestion of the polysaccharides, probably due to electrostatic cross-bridging of the matrix nucleic acids, which explains why α-amylase fails to improve the antibacterial action of the peptide.

The bacteriology of diabetic foot ulcers and infections and incidence of Staphylococcus aureus Small Colony Variants

Introduction. Uninfected diabetes-related foot ulcer (DFU) progression to diabetes-related foot infection (DFI) is a prevalent complication for patients with diabetes. DFI often progresses to osteomyelitis (DFI-OM). Active (growing) Staphylococcus aureus is the most common pathogen in these infections. There is relapse in 40-60 % of cases even when the initial treatment at the DFI stage apparently clears infection.Hypothesis. S. aureus adopts the quasi-dormant Small Colony Variant (SCV) state during DFU and consequently infection, and when present in DFI cases also permits survival in non-diseased tissues as a reservoir to cause relapse.Aim. The aim of this study was to investigate the bacterial factors that facilitate persistent infections.Methodology. People with diabetes were recruited from two tertiary hospitals. Clinical and bacterial data was taken from 153 patients with diabetes (51 from a control group with no ulcer or infection) and samples taken from 102 patients with foot complications to identify bacterial species and their variant colony types, and then compare the bacterial composition in those with uninfected DFU, DFI and those with DFI-OM, of whom samples were taken both from wounds (DFI-OM/W) and bone (DFI-OM/B). Intracellular, extracellular and proximal 'healthy' bone were examined.Results. S. aureus was identified as the most prevalent pathogen in diabetes-related foot pathologies (25 % of all samples). For patients where disease progressed from DFU to DFI-OM, S. aureus was isolated as a diversity of colony types, with increasing numbers of SCVs present. Intracellular (bone) SCVs were found, and even within uninfected bone SCVs were present. Wounds of 24 % of patients with uninfected DFU contained active S. aureus. All patients with a DFI with a wound but not bone infection had previously had S. aureus isolated from an infection (including amputation), representing a relapse.Conclusion. The presence of S. aureus SCVs in recalcitrant pathologies highlights their importance in persistent infections through the colonization of reservoirs, such as bone. The survival of these cells in intracellular bone is an important clinical finding supporting in vitro data. Also, there seems to be a link between the genetics of S. aureus found in deeper infections compared to those only found in DFU.

Consensus-based recommendations on physical activity and exercise in patients with diabetes at risk of foot ulcerations: a Delphi study

BACKGROUND

Patients with diabetes mellitus are exposed to important complications. Currently little evidence exist on the guidelines that these patients, at some risk of foot ulceration, should follow for physical exercise.

OBJECTIVES

To reach a consensus among multidisciplinary and international experts on physical activity/exercise recommendations for patients with diabetes, according to foot ulcer risk.

METHODS

Using a three-round Delphi method, a panel composed of 28 multidisciplinary experts in the management of diabetic foot assessed 109 recommendations on physical activity/exercise for patients with diabetes mellitus, according to their risk of foot ulcer. Consensus was assumed when 80% of responses matched the same category (agreement/disagreement).

RESULTS

Twenty-nine experts participated in the first and second rounds of consultation, and twenty-eight did so in the third, reaching final agreement on 86 of the 109 recommendations considered (78.9%). The study, thus, generated a consensus set of recommendations concerning different aspects of diabetic footcare before, during, and after exercise (e.g. when to examine the foot, how to assess it, what type of sock and insole to use, what types of exercise to perform, and when it is advisable to return to activity after an ulceration).

CONCLUSION

This Delphi study generated recommendations based on the consensus of international experts on physical activity and exercise by patient with diabetes at risk of ulceration. Recommendations considered the state of the foot and the patient's history and status before physical activity and included information on intensity, duration, frequency, and progressions of physical activity/exercise, and the use of custom-made plantar orthoses, shoe prescription, and the convenience of returning to physical activity after an ulceration.

Distribution of Causative Microorganisms in Diabetic Foot Infections: A Ten-Year Retrospective Study in a Tertiary Care Hospital in Central Malaysia

Diabetes mellitus is a global pandemic, especially in Southeast Asia. Diabetic foot infection (DFI) is a common complication of this condition and causes significant morbidity and mortality in those affected. There is a lack of locally published data on the types of microorganisms and empirical antibiotics being prescribed. This paper highlights the importance of local microorganism culture and antibiotic prescription trends among diabetic foot patients in a tertiary care hospital in central Malaysia. This is a retrospective, cross-sectional study of data taken from January 2010 to December 2019 among 434 patients admitted with diabetic foot infections (DFIs) using the Wagner classification. Patients between the ages of 58 and 68 years old had the highest rate of infection. Pseudomonas Aeruginosa, Proteus spp., and Proteus mirabilis appeared to be the most isolated Gram-negative microorganisms, and Staphylococcus aureus, Streptococcus agalactiae, and MRSA appeared to be the most common Gram-positive microorganisms. The most common empirical antibiotics prescribed were ampicillin/sulbactam, followed by ciprofloxacin and ceftazidime, and the most common therapeutic antibiotics prescribed were ampicillin/sulbactam, ciprofloxacin, and cefuroxime. This study could be immensely pertinent in facilitating future empirical therapy guidelines for treating diabetic foot infections.

Effect of Vancomycin Applied to the Surgical Site on Fracture Healing in a Diabetic Rat Model

BACKGROUND

Prophylactic vancomycin treatment decreases the prevalence of surgical site and deep infections by >70% in diabetic patients undergoing reconstructive foot and ankle surgery. Thus, determining whether clinically relevant local vancomycin doses affect diabetic fracture healing is of medical interest. We hypothesized that application of vancomycin powder to the fracture site during surgery would not affect healing outcomes, but continuous exposure of vancomycin would inhibit differentiation of osteoblast precursor cells and their osteogenic activity in vitro.

METHODS

The vancomycin dose used to treat the diabetic rats was a modest increase to routine surgical site vancomycin application of 1 to 2 g for a 70-kg adult (21 mg/kg). After femur fracture in BB-Wistar type 1 diabetic rats, powdered vancomycin (25 mg/kg) was administered to the fracture site. Bone marrow and periosteal cells isolated from diabetic bones were cultured and treated with increasing levels of vancomycin (0, 5, 50, 500, or 5000 µg/mL).

RESULTS

Radiographic scoring, micro-computed tomography (µCT) analysis, and torsion mechanical testing failed to identify any statistical difference between the vancomycin-treated and the untreated fractured femurs 6 weeks postfracture. Low to moderate levels of vancomycin treatment (5 and 50 µg/mL) did not impair cell viability, osteoblast differentiation, or calcium deposition in either the periosteum or bone marrow-derived cell cultures. In contrast, high doses of vancomycin (5000 µg/mL) did impair viability, differentiation, and calcium deposition.

CLINICAL RELEVANCE

In this diabetic rodent fracture model, vancomycin powder application at clinically relevant doses did not affect fracture healing or osteogenesis.

Antibacterial, Adhesive, and Conductive Hydrogel for Diabetic Wound Healing

Diabetic mellitus is one of the leading causes of chronic wounds and remains a challenging issue to be resolved. Herein, a hydrogel with conformal tissue adhesivity, skin-like conductivity, robust mechanical characteristics, as well as active antibacterial function is developed. In this hydrogel, silver nanoparticles decorated polypyrrole nanotubes (AgPPy) and cobalt ions (Co²⁺ ) are introduced into an in situ polymerized poly(acrylic acid) (PAA) and branched poly(ethylenimine) (PEI) network (PPCA hydrogel). The PPCA hydrogel provides active antibacterial function through synergic effects from protonated PEI and AgPPy nanotubes, with a tissue-like mechanical property (≈16.8 ± 4.5 kPa) and skin-like electrical conductivity (≈0.048 S m^-1 ). The tensile and shear adhesive strength (≈15.88 and ≈12.76 kPa, respectively) of the PPCA hydrogel is about two- to threefold better than that of fibrin glue. In vitro studies show the PPCA hydrogel is highly effective against both gram-positive and gram-negative bacteria. In vivo results demonstrate that the PPCA hydrogel promotes diabetic wounds with accelerated healing, with notable inflammatory reduction and prominent angiogenesis regeneration. These results suggest the PPCA hydrogel provide a promising approach to promote diabetic wound healing.

Cost-effectiveness of Novel Macrophage-Regulating Treatment for Wound Healing in Patients With Diabetic Foot Ulcers From the Taiwan Health Care Sector Perspective

IMPORTANCE

Diabetic foot ulcers (DFUs) and subsequent amputation incur enormous health and economic burdens to patients, health care systems, and societies. As a novel macrophage-regulating drug, ON101 is a breakthrough treatment for DFUs, which demonstrated significant complete wound healing effects in a phase 3 randomized clinical trial, but its economic value remains unknown.

OBJECTIVE

To assess the cost-effectiveness of an ON101 cream added on to general wound care (GWC; ie, conventional treatments for DFUs, which comprised initial and regular foot examinations, ulcer management, comorbidity control, patient education, and multidisciplinary care) vs GWC alone for DFUs from the Taiwan health care sector perspective.

DESIGN, SETTING, AND PARTICIPANTS

This economic evaluation used a hypothetical cohort of patients with diabetes, with characteristics mirroring those of the participants in the ON101 trial. A Markov state-transition simulation model was constructed to estimate costs and health outcomes associated with the ON101 with GWC and GWC alone strategies over a 5-year time horizon, discounting costs and effectiveness at 3% annually. Costs were in 2021 US dollars. Data were sourced from the ON101 trial and supplemented from published literature. Deterministic and probabilistic sensitivity analyses were performed to assess the uncertainty of input parameters and study generalizability. The analysis was designed and conducted from September 1, 2020, to January 31, 2022.

EXPOSURES

ON101 with GWC vs GWC alone.

MAIN OUTCOMES AND MEASURES

DFU-related complications, costs, quality-adjusted life-years (QALYs), and incremental cost-effectiveness ratio.

RESULTS

Patients in the hypothetical cohort had a mean age of 57 years and an uninfected DFU of 1 to 25 cm2 that was present for 4 or more weeks with a Wagner grade of 1 or 2. Over 5 years, the ON101 with GWC group vs the GWC alone group experienced more healing events, stayed for a longer time in the healing state, and had fewer infected DFUs, gangrene, and amputations (eg, 2787 additional healing events and 2766 fewer infected DFU, 72 fewer amputation, and 7 fewer gangrene events in the ON101 with GWC group vs GWC alone group). The ON101 with GWC strategy vs GWC alone yielded an additional 0.038 QALYs at an incremental cost of $571, resulting in $14 922/QALY gained. Economic results were most sensitive to healing efficacy, drug cost, and health utility of the healing state. Cost-saving results were observed in patient subgroups with poor glycemic control, larger ulcer sizes, longer ulcer durations, and current smoking. The ON101 with GWC strategy was considered cost-effective in 60% to 82% of model iterations against willingness-to-pay thresholds of $32 787/QALY gained to $98 361/QALY gained.

CONCLUSIONS AND RELEVANCE

In this economic evaluation study using a simulated patient cohort, the ON101 with GWC strategy represented good value compared with GWC alone for patients with DFUs from the Taiwan health care sector perspective and may be prioritized for those with high risks for disease progression of DFUs.

Microenvironment-Based Diabetic Foot Ulcer Nanomedicine

Diabetic foot ulcers (DFU), one of the most serious complications of diabetes, are essentially chronic, nonhealing wounds caused by diabetic neuropathy, vascular disease, and bacterial infection. Given its pathogenesis, the DFU microenvironment is rather complicated and characterized by hyperglycemia, ischemia, hypoxia, hyperinflammation, and persistent infection. However, the current clinical therapies for DFU are dissatisfactory, which drives researchers to turn attention to advanced nanotechnology to address DFU therapeutic bottlenecks. In the last decade, a large number of multifunctional nanosystems based on the microenvironment of DFU have been developed with positive effects in DFU therapy, forming a novel concept of "DFU nanomedicine". However, a systematic overview of DFU nanomedicine is still unavailable in the literature. This review summarizes the microenvironmental characteristics of DFU, presents the main progress of wound healing, and summaries the state-of-the-art therapeutic strategies for DFU. Furthermore, the main challenges and future perspectives in this field are discussed and prospected, aiming to fuel and foster the development of DFU nanomedicines successfully.

The association between micronutrient levels and diabetic foot ulcer: A systematic review with meta-analysis

BACKGROUND

Diabetic foot ulcers (DFU) are a major complication of diabetes mellitus (DM). Nutrient deficiencies are among the major risk factors in DFU development and healing. In this context, we aimed to investigate the possible association between micronutrient status and risk of DFU.

METHODS

A systematic review (Prospero registration: CRD42021259817) of articles, published in PubMed, Web of Science, Scopus, CINAHL Complete, and Embase, that measured the status of micronutrients in DFU patients was performed.

RESULTS

Thirty-seven studies were considered, of which thirty were included for meta-analysis. These studies reported levels of 11 micronutrients: vitamins B9, B12, C, D, E, calcium, magnesium, iron, selenium, copper, and zinc. DFU, compared to healthy controls (HC) had significantly lower vitamin D (MD: -10.82 14 ng/ml, 95% CI: -20.47, -1.16), magnesium (MD: -0.45 mg/dL, 95% CI: -0.78, -0.12) and selenium (MD: -0.33 µmol/L, 95% CI: -0.34, -0.32) levels. DFU, compared to DM patients without DFU, had significantly lower vitamin D (MD: -5.41 ng/ml, 95% CI: -8.06, -2.76), and magnesium (MD: -0.20 mg/dL, 95% CI: -0.25, -0.15) levels. The overall analysis showed lower levels of vitamin D [15.55ng/ml (95% CI:13.44, 17.65)], vitamin C [4.99µmol/L (95% CI:3.16, 6.83)], magnesium [1.53mg/dL (95% CI:1.28, 1.78)] and selenium [0.54µmol/L (95% CI:0.45, 0.64)].

CONCLUSION

This review provides evidence that micronutrient levels significantly differ in DFU patients, suggesting an association between micronutrient status and risk of DFU. Therefore, routine monitoring and supplementations are warranted in DFU patients. We suggest that personalized nutrition therapy may be considered in the DFU management guidelines.

SYSTEMATIC REVIEW REGISTRATION

https://www.crd.york.ac.uk/PROSPERO/display_record.php?RecordID=259817, identifier CRD42021259817.

Factors Associated with Infection Severity of Diabetic Foot Ulcers: A Cross-Sectional Study

Background: Infection in the ulcerated foot is a foremost cause of morbidity, constituting the biggest proportion of hospitalization and amputation among patients with diabetic foot ulcers. Assessment of infection severity lays a foundation for making treatment decisions, for which the IDSA/IWGDF classification is recommended. Different factors may cause various severity of infection. However, few investigations have been conducted concerning factors associated with infection severity of diabetic foot ulcers. Objective: To investigate factors associated with infection severity of diabetic foot ulcers. Methods: This cross-sectional study involved 150 subjects hospitalized in the Department of Endocrinology of Sun Yat-sen Memorial Hospital in Guangdong Province between July 2020 and September 2021. The IDSA/IWGDF classification was adopted to assess ulcer infection severity. Demographic and disease information, laboratory reports, and ulcer assessment results were evaluated for an association with the infection severity. The generalized linear model was performed to conduct multivariate analyses of the factors associated with the severity of foot infection. Results: The prevalence of mild, moderate, and severe infected diabetic foot was 23.3%, 64.7% and 10.2%, respectively. The results of generalized linear models showed a correlation between Alb (OR = -1.74, 95%CI1.12-6.58, p = .023), CRP (OR = 2.13, 95%CI1.38-7.21, p = .014), PCT (OR = 2.01, 95%CI1.29-7.64, p = .013), microbial type (OR = 2.04, 95%CI1.43-7.83, p = .004) and ulcer infection severity. Conclusion: Alb, CRP, PCT and microbial type were among the factors influencing infection severity of diabetic foot ulcers.

Microbiota of diabetic foot infections in a University Hospital in Bogotá, Colombia

The presence of infection in diabetic foot ulcers (DFU) is one of the main causes of lower limb amputation in the world. The presence of polymicrobial infections is usually the standard for isolation in such lesions, with Gram Positive (GP) germs being the main organisms involved, as is described in the global literature. However, some studies indicate a greater number of isolates with Gram Negative (GN) germs, reported mainly in the literature of Middle Eastern countries and in the tropics.

Nisin Mutant Prevention Concentration and the Role of Subinhibitory Concentrations on Resistance Development by Diabetic Foot Staphylococci

The most prevalent microorganism in diabetic foot infections (DFI) is Staphylococcus aureus, an important multidrug-resistant pathogen. The antimicrobial peptide nisin is a promising compound for DFI treatment, being effective against S. aureus. However, to avoid the selection of resistant mutants, correct drug therapeutic doses must be established, being also important to understand if nisin subinhibitory concentrations (subMIC) can potentiate resistant genes transfer between clinical isolates or mutations in genes associated with nisin resistance. The mutant selection window (MSW) of nisin was determined for 23 DFI S. aureus isolates; a protocol aiming to prompt vanA horizontal transfer between enterococci to clinical S. aureus was performed; and nisin subMIC effect on resistance evolution was assessed through whole-genome sequencing (WGS) applied to isolates subjected to a MEGA-plate assay. MSW ranged from 5–360 μg/mL for two isolates, from 5–540 μg/mL for three isolates, and from 5–720 μg/mL for one isolate. In the presence of nisin subMIC values, no transconjugants were obtained, indicating that nisin does not seem to promote vanA transfer. Finally, WGS analysis showed that incubation in the presence of nisin subMIC did not promote the occurrence of significant mutations in genes related to nisin resistance, supporting nisin application to DFI treatment.

Predicting Amputation in Patients With Diabetic Foot Ulcers: A Systematic Review

Foot ulcers are a leading cause of morbidity in diabetics. One of the known complications of diabetic foot ulcers is lower limb amputation which makes it a major socioeconomic problem. Currently, there's a lack of knowledge on the predictors of amputations in diabetics with foot ulcers. We performed a systematic review of studies that identified risk factors of amputation in patients with diabetic foot ulcers. This systematic review aims to identify the predictors of amputation in order to optimize the management strategy and care plan. Medline database was searched and inclusion criteria were implemented for the selection of studies. The risk factors extracted were part of four categories: (i) history and physical examination, (ii) ulcer characteristics, (iii) lab results, and (iv) co-morbidities. The data extracted were in the form of odds ratios, 95% confidence intervals, and predictive values. The mean values with standard deviations of the included risk factors were recorded, and the incidence of risk factors among the amputation groups was identified or calculated when the data were sufficient. Seven articles were selected reporting on 3481 patients. This review identified peripheral arterial disease, neuropathy, high Wagner's grade, osteomyelitis, postprandial glucose level, white cell count, c-reactive protein, erythrocyte sedimentation rate, low hemoglobin, and albumin as the most significant predictors of amputation.

Prevalence and Predictors of Pseudomonas aeruginosa among Hospitalized Patients with Diabetic Foot Infections

Background

Diabetic foot infections (DFIs) are commonly associated with antibiotic overuse. Empiric DFI treatment often includes coverage for Pseudomonas aeruginosa (PsA), but the frequency of PsA DFIs is poorly understood. The study objectives were to quantify the prevalence of and determine predictors for PsA DFIs.

Methods

This multicenter, retrospective cohort included hospitalized patients with DFI from 2013 through 2020 who were age ≥18 years; diabetes mellitus diagnosis; and DFI based on International Classification of Diseases, Tenth Revision coding, antibiotic treatment, and DFI culture with organism growth. Osteomyelitis was excluded. Patient characteristics were described and compared; the primary outcome was presence of PsA on DFI culture. Predictors of PsA DFI were identified using multivariable logistic regression.

Results

Two hundred ninety-two patients were included. The median age was 61 (interquartile range [IQR], 53–69) years; the majority were men (201 [69%]) and White (163 [56%]). The most commonly isolated organisms were methicillin-susceptible Staphylococcus aureus (35%) and streptococci (32%); 147 (54%) cultures were polymicrobial. Two hundred fifty-seven (88%) patients received empiric antibiotics active against PsA, but only 27 (9%) patients had PsA DFI. Immunocompromised status (adjusted odds ratio [aOR], 4.6 [95% confidence interval {CI}, 1.3–16.7]) and previous outpatient DFI antibiotic treatment failure (aOR, 4.8 [95% CI, 1.9–11.9]) were associated with PsA DFI.

Conclusions

PsA DFI is uncommon, but most patients receive empiric antipseudomonal antibiotics. Empiric broad-spectrum antibiotics are warranted given the frequency of mixed infections, but patient-specific risk factors should be considered before adding antipseudomonal coverage.

Diabetic foot infections: A microbiologic review

Diabetes mellitus continues to be an increasingly common comorbidity. Diabetic foot infections are one of the most common causes of hospitalization in this population, and account for a significant portion of increased hospitalization and healthcare expenditure. Complications, such as osteomyelitis, can necessitate the use of multiple, prolonged antibiotic courses. These courses often consist of broad-spectrum, empiric therapy determined by organisms considered to be commonly associated with these types of infections. Extended periods of broad-spectrum antibiotic regimens can contribute to antibiotic resistance and ultimately limit future treatment options. Furthermore, patient specific risk factors can impact the microbiologic diversity found in these infections. As a result, it is difficult to determine if a single empiric regimen is appropriate for all instances of diabetic foot infections.

OBJECTIVES AND METHODS

This review analyzes global literature relating to the culture methods, incidence, risk factors, resistance patterns, and geographic distribution of the microorganisms isolated from diabetic foot infections using the PRISMA statement for systematic review and meta-analysis reporting.

RESULTS

Staphylococcus aureus remains a significant pathogen, with a growing incidence of Pseudomonas aeruginosa and MDR gram-negative bacilli.

CONCLUSIONS

Though some individualized risk factors can be useful, local epidemiology and resistance patterns remain essential for antibiotic treatment considerations.

Use of injectable acellular dermal matrix combined with negative pressure wound therapy in open diabetic foot amputation

Objective:

Skin grafts after negative pressure wound therapy (NPWT) and acellular dermal matrix (ADM) usage have both been useful for treating diabetic foot amputation. We hypothesised that injectable ADM combined with NPWT would be more useful than NPWT only for healing after amputation in patients with diabetic foot ulcers (DFUs). The aim of this study was to investigate the clinical outcomes of injectable ADM combined with NPWT in patients with DFU who have undergone amputation.

Method:

This retrospective study reviewed patients with infected DFUs who were administered NPWT. Patients were divided into two groups: Group 1 included patients who were treated with NPWT only, while Group 2 included patients who were treated with injectable ADM combined with NPWT. Clinical results including the number of NPWT dressing changes, wound healing duration, and full-thickness skin graft (FTSG) incident rate between the two groups were compared.

Results:

A total of 41 patients took part in the study (Group 1=20, Group 2=21). The mean number of NPWT dressing changes was significantly lower in Group 2 (8.71±3.77) than in Group 1 (13.90±5.62) (p=0.001). Mean wound healing period was shorter in Group 2 (3.17±1.36 weeks) than in Group 1 (5.47±1.68 weeks) (p=0.001). Finally, the rate of patients who underwent FTSG for complete wound closure was 85% in Group 1, whereas it was only 14.3% in Group 2.

Conclusion:

In this study, the use of injectable ADM combined with NPWT in patients with DFU who underwent amputation favoured complete wound healing, without the need to resort to the use of skin grafts.

Complex Foot Infection Treated With Surgical Debridement and Antibiotic Loaded Calcium Sulfate-A Retrospective Cohort Study of 137 Cases

Complex foot infections involving bone and soft tissue in patients with co-morbidities such as diabetes and peripheral arterial disease (PAD) are a cause of significant hospital admission. They are associated with substantial economic costs to health services worldwide. Historically, severe foot infection has been treated with surgical debridement and prolonged courses of systemic antibiotics. Prolonged systemic antibiotic use increases the risk of drug side effects, antimicrobial resistance and Clostridium difficile infection. The purpose of this study was to investigate whether surgical debridement and implantation of antibiotic loaded calcium sulfate is effective in the resolution of foot infection and wound healing. A retrospective cohort study of 137 consecutive cases of osteomyelitis (127) or significant soft tissue infection (10) over 62 months from 02/2013 to 04/2018 was conducted following local ethical approval. All cases of infection were treated with surgical debridement and local antibiotic-loaded calcium sulfate. The primary outcomes of infection resolution, time to healing and duration of postoperative antibiotics were measured. In 137 cases, 88.3% of infections resolved. Infection was eradicated in 22 patients without postoperative systemic antibiotics. About 82.5% of wounds healed, with an average healing time of 11.3 weeks. Healing time was significantly increased for the co-morbidities of diabetes and PAD (p =< .05) and for those requiring prolonged systemic postoperative antibiotics. Conservative surgical debridement and implantation of local antibiotic impregnated calcium sulfate is safe and effective in managing complex foot infections. We advocate early surgical intervention before deeper tissue involvement to help preserve lower limb structure and function.

Efficacy and Safety of Topical Solution of Diperoxochloric Acid for Neuropathic Diabetic Foot Ulcer: Results from a Phase 3, Multicentre, Randomized, Active-controlled, Parallel-group Study

Diabetic foot ulcer (DFU), if untreated, accounts for lower-limb amputations affecting patients' quality-of-life. Diperoxochloric acid (DPOCL) is known to heal DFU by its antibacterial and fibroblast stimulating activity. This was a phase 3, multicentre, randomized, double-blind, active-controlled, parallel-group study conducted to evaluate the efficacy and safety of topic solution of DPOCL compared with isotonic sodium chloride solution (ISCL). Adult patients with type 1 or 2 diabetes with random blood glucose levels of <250 mg/dL, with ≤ than three full-thickness foot ulcers were enrolled. Primary efficacy endpoint was complete wound closure and secondary was wound surface area. Adverse events were analyzed as safety endpoint. Of 311 enrolled patients, 289 were randomized 1:1 to DPOCL (139) and ISCL (150) treatment (10-weeks [8-Visits]). Percentage of patients with complete wound closure at visit-8, were significantly higher (P = .0156) in DPOCL arm (76% [105/139]) compared to ISCL (62% [93/150]) arm. At end-of-study, mean wound surface area in DPOCL arm (0.639 cm2) was significantly lower (P = .0209) compared to ISCL (0.818 cm2) arm. One death was reported in control arm which was not considered as treatment-related. No important safety finding were observed. Results indicate that, DPOCL can be considered as effective and safe treatment option for DFU compared to ISCL, although future confirmatory studies are warranted.

Association Between Vitamin D Status and Diabetic Foot in Patients With Type 2 Diabetes Mellitus

Aims/Introduction

To assess the association between vitamin D and diabetic foot (DF) in patients with type 2 diabetes mellitus (T2DM), in order to summarize clinical evidence in the prevention and treatment of DF.

Materials and methods

Between January 2012 and December 2019, a total of 1,721 hospitalized patients with type 2 diabetes mellitus were continuously enrolled in West China Hospital, Sichuan University, and divided into DF and non‐DF groups according to whether they had DF, and divided into four subgroups according to the admission season. The 25‐OH‐vitamin D levels were compared between groups and subgroups, and independent risk factors discussed for the occurrence of DF.

Results

The vitamin D insufficiency and deficiency rate were higher in the DF group (77.51%) than in the non‐DF group (59.2%). The 25‐OH‐vitamin D levels were lower in the DF group (35.80 nmol/L) than in the non‐DF group (45.48 nmol/L) (P < 0.001). Patients with poor glycemic control had lower 25‐OH‐vitamin D levels (P = 0.01). The levels of 25‐OH‐vitamin D were lower in winter and spring. In the same season, the levels of 25‐OH‐vitamin D in patients with DF were still lower (P < 0.001). The 25‐OH‐vitamin D levels of patients with Wagner grades 0 to 5 showed a downward trend (P = 0.114). The 25‐OH‐vitamin D level was independently associated with diabetic foot (P < 0.001, OR = 0.986).

Conclusions

The low serum vitamin D level was significantly associated with a higher prevalence of DF among Chinese patients with type 2 diabetes mellitus. Although vitamin D levels vary seasonally, patients with DF were always at higher risk of having vitamin D insufficiency and deficiency.

Diabetic Foot Ulcer Infections and Pseudomonas aeruginosa Biofilm Production During the COVID-19 Pandemic

During the different waves of the coronavirus (COVID-19) pandemic, there has been an increased incidence of diabetes mellitus and diabetic foot infections. Among gram-negative bacteria, Pseudomonas aeruginosa is the predominant causative agent for diabetic foot ulcer infections in low-resource countries. P. aeruginosa possesses a variety of virulence factors, including biofilm formation. Biofilm formation is an important benchmark characteristic in the pathophysiology of diabetic foot ulceration. The main objective of the current study was to identify the most commonly isolated organisms and their antibiotic susceptibility patterns in diabetic foot patients during the COVID-19 pandemic. We also determined the genes associated with bacterial persistence and biofilm formation in the predominantly isolated organism. Accordingly, 100 wound swab samples were collected from diabetic foot patients from different hospitals in Alexandria, Egypt. Through phenotypic detection of biofilm formation, 93% (40) of the 43 P. aeruginosa isolates examined were categorized as biofilm producers. Molecular detection of the biofilm-encoding genes among the 43 P. aeruginosa isolates was as follows: algD (100%), pelF (88%) and pslD (49.7%), and this highlights a need for biofilm formation inhibitors to prevent the persistence of bacterial pathogens, and thus achieve better clinical outcomes in diabetic foot ulcer infections.

Predicting the Risk of Diabetic Foot Ulcers From Diabetics With Dysmetabolism: A Retrospective Clinical Trial

BACKGROUND

Diabetic foot ulcer (DFU) in patients with type 2 diabetes mellitus (T2D) often leads to amputation. Early intervention to prevent DFU is urgently necessary. So far, there have been no studies on predictive models associated with DFU risk factors. Our study aimed to quantify the predictive risk value of DFU, promote health education, and further develop behavioral interventions to reduce the incidence of DFU.

METHODS

Data from 973 consecutive patients with T2D was collected from two hospitals. Patients from the Guangxi Medical University First Affiliated Hospital formed the training cohort (n = 853), and those from the Wuming Hospital of Guangxi Medical University formed the validation cohort (n = 120). Independent variable grouping analysis and multivariate logistic regression analysis were used to determine the risk factors of DFUs. The prediction model was established according to the related risk factors. In addition, the accuracy of the model was evaluated by specificity, sensitivity, predictive value, and predictive likelihood ratio.

RESULTS

In total, 369 of the 853 patients (43.3%) and 60 of the 120 (50.0%) were diagnosed with DFUs in the two hospitals. The factors associated with DFU were old age, male gender, lower body mass index (BMI), longer duration of diabetes, history of foot disease, cardiac insufficiency, no use of oral hypoglycemic agent (OHA), high white blood cell count, high platelet count, low hemoglobin level, low lymphocyte absolute value, and high postprandial blood glucose. After incorporating these 12 factors, the nomogram drawn achieved good concordance indexes of 0.89 [95% confidence interval (CI): 0.87 to 0.91] in the training cohort and 0.84 (95% CI: 0.77 to 0.91) in the validation cohort in predicting DFUs and had well-fitted calibration curves. Patients who had a nomogram score of ≥180 were considered to have a low risk of DFU, whereas those having ≥180 were at high risk.

CONCLUSIONS

A nomogram was constructed by combining 12 identified risk factors of DFU. These 12 risk factors are easily available in hospitalized patients, so the prediction of DFU in hospitalized patients with T2D has potential clinical significance. The model provides a reliable prediction of the risk of DFU in patients with T2D.

Bioactive Antimicrobial Peptides as Therapeutic Agents for Infected Diabetic Foot Ulcers

Diabetic foot ulcer (DFU) is a devastating complication, affecting around 15% of diabetic patients and representing a leading cause of non-traumatic amputations. Notably, the risk of mixed bacterial–fungal infection is elevated and highly associated with wound necrosis and poor clinical outcomes. However, it is often underestimated in the literature. Therefore, polymicrobial infection control must be considered for effective management of DFU. It is noteworthy that antimicrobial resistance is constantly rising overtime, therefore increasing the need for new alternatives to antibiotics and antifungals. Antimicrobial peptides (AMPs) are endogenous peptides that are naturally abundant in several organisms, such as bacteria, amphibians and mammals, particularly in the skin. These molecules have shown broad-spectrum antimicrobial activity and some of them even have wound-healing activity, establishing themselves as ideal candidates for treating multi-kingdom infected wounds. Furthermore, the role of AMPs with antifungal activity in wound management is poorly described and deserves further investigation in association with antibacterial agents, such as antibiotics and AMPs with antibacterial activity, or alternatively the application of broad-spectrum antimicrobial agents that target both aerobic and anaerobic bacteria, as well as fungi. Accordingly, the aim of this review is to unravel the molecular mechanisms by which AMPs achieve their dual antimicrobial and wound-healing properties, and to discuss how these are currently being applied as promising therapies against polymicrobial-infected chronic wounds such as DFUs.

Growth factors, as biological macromolecules in bioactivity enhancing of electrospun wound dressings for diabetic wound healing: A review

Impaired wound healing is of the most conspicuous characteristics of diabetic mellitus. Reduced blood flow, chronic inflammatory reactions, infection, endothelial dysfunction, elevated levels of reactive oxygen species, and metabolic disorders cause wounds to heal more slowly in these patients. Previous studies have reported useful impacts of growth factors in management of such wounds. However, due to their short half-life and low stability, a suitable delivery platform with sustained release profile may boost their healing potential. Controlled and localized delivery of growth factors via electrospun fibers have been extensively explored in previous studies. The electrospinning method; although not new, has turned out to be extremely effective for the preparation of delivery carriers for growth factors. Due to their structural resemblance to native tissues' extracellular matrix, high encapsulation efficacy, tunability, and high surface to volume ratio, electrospun scaffolds have gained significant attention in drug delivery and tissue engineering. In the current review, careful integration of current research regarding the applications of growth factors' delivery through electrospun fibers in diabetic wounds healing has been done. This review will not only give an insight into the current updates, but will also highlights the future perspectives and challenges.

Hyperbaric oxygen enhances collagen III formation in wound of ZDF rat

Diabetic foot ulcer (DFU) is a serious complication of diabetes and hyperbaric oxygen therapy (HBOT) is also considered in comprehensive treatment. The evidence supporting the use of HBOT in DFU treatment is controversial. The aim of this work was to introduce a DFU model in ZDF rat by creating a wound on the back of an animal and to investigate the effect of HBOT on the defect by macroscopic evaluation, quantitative histological evaluation of collagen (types I and III), evaluation of angiogenesis and determination of interleukin 6 (IL6) levels in the plasma. The study included 10 rats in the control group (CONT) and 10 in the HBOT group, who underwent HBOT in standard clinical regimen. Histological evaluation was performed on the 18th day after induction of defect. The results show that HBOT did not affect the macroscopic size of the defect nor IL6 plasma levels. A volume fraction of type I collagen was slightly increased by HBOT without reaching statistical significance (1.35+/-0.49 and 1.94+/-0.67 %, CONT and HBOT, respectively). In contrast, the collagen type III volume fraction was ~120 % higher in HBOT wounds (1.41+/-0.81 %) than in CONT ones (0.63+/-0.37 %; p=0.046). In addition, the ratio of the volume fraction of both collagens in the wound ((I+III)w) to the volume fraction of both collagens in the adjacent healthy skin ((I+III)h) was ~65 % higher in rats subjected to HBOT (8.9+/-3.07 vs. 5.38+/-1.86 %, HBOT and CONT, respectively; p=0.028). Vessels density (number per 1 mm2) was found to be higher in CONT vs. HBOT (206.5+/-41.8 and 124+/-28.2, respectively, p<0.001). Our study suggests that HBOT promotes collagen III formation and decreases the number of newly formed vessels at the early phases of healing.

Retrospective Observational Study on Microbial Contamination of Ulcerative Foot Lesions in Diabetic Patients

According to recent studies, there are almost 435 million people worldwide with diabetes mellitus. It is estimated that of these 148 million will develop Diabetic foot ulcers (DFUs) during their lifetime, of which 35 to 50% will be infected. In this scenario, the presence and frequency of pathogenic microorganisms and their level of susceptibility to the most frequent classes of antibiotics used to treat this pathological condition from patients with DFUs admitted to the outpatient clinic of vascular surgery of the Federico II University Hospital of Naples from January 2019 to March 2021 were investigated. Furthermore, the diabetic population characteristics under study (i.e., general, clinical, and comorbidities) and the pathogenic bacteria isolated from lesions were also considered. Bacterial strains poorly susceptible to antibiotics were more frequent in polymicrobial infections than in monomicrobial infections. β-Lactams showed the highest levels of resistance, followed by fluoroquinolones, aminoglycosides, and finally macrolides. The main findings of the study demonstrated that the occurrence of resistant microorganisms is the dominant factor in ulcer healing; thus it is essential to investigate the antibiotics’ susceptibility before setting antibiotic therapy to avoid inappropriate prescriptions that would affect the treatment and increase the development and spread of antibiotic resistance.

Pathophysiology and Molecular Imaging of Diabetic Foot Infections

Diabetic foot infection is the leading cause of non-traumatic lower limb amputations worldwide. In addition, diabetes mellitus and sequela of the disease are increasing in prevalence. In 2017, 9.4% of Americans were diagnosed with diabetes mellitus (DM). The growing pervasiveness and financial implications of diabetic foot infection (DFI) indicate an acute need for improved clinical assessment and treatment. Complex pathophysiology and suboptimal specificity of current non-invasive imaging modalities have made diagnosis and treatment response challenging. Current anatomical and molecular clinical imaging strategies have mainly targeted the host's immune responses rather than the unique metabolism of the invading microorganism. Advances in imaging have the potential to reduce the impact of these problems and improve the assessment of DFI, particularly in distinguishing infection of soft tissue alone from osteomyelitis (OM). This review presents a summary of the known pathophysiology of DFI, the molecular basis of current and emerging diagnostic imaging techniques, and the mechanistic links of these imaging techniques to the pathophysiology of diabetic foot infections.

Pathophysiology and Molecular Imaging of Diabetic Foot Infections

Diabetic foot infection is the leading cause of non-traumatic lower limb amputations worldwide. In addition, diabetes mellitus and sequela of the disease are increasing in prevalence. In 2017, 9.4% of Americans were diagnosed with diabetes mellitus (DM). The growing pervasiveness and financial implications of diabetic foot infection (DFI) indicate an acute need for improved clinical assessment and treatment. Complex pathophysiology and suboptimal specificity of current non-invasive imaging modalities have made diagnosis and treatment response challenging. Current anatomical and molecular clinical imaging strategies have mainly targeted the host's immune responses rather than the unique metabolism of the invading microorganism. Advances in imaging have the potential to reduce the impact of these problems and improve the assessment of DFI, particularly in distinguishing infection of soft tissue alone from osteomyelitis (OM). This review presents a summary of the known pathophysiology of DFI, the molecular basis of current and emerging diagnostic imaging techniques, and the mechanistic links of these imaging techniques to the pathophysiology of diabetic foot infections.

Multidrug-resistant Bacterial Profile and Patterns for Wound Infections in Nongovernmental Hospitals of Jordan

Globally, multidrug-resistant bacteria affects wound infections, both hospital-acquired infections and community-acquired infections. The main isolates cultured from 607 subjects with wound infections were methicillin-resistant Staphylococcus aureus (MRSA), Escherichia coli, Pseudomonas aeruginosa, and Acinetobacter spp. [multidrug resistant (MDR)]. Gram-negative bacteria caused most of the infections (67%) compared with gram-positive bacteria. Diabetic patients tend to have wound infections with mixed causative agents compared with non-diabetic patients.

Can Intralesional Epidermal Growth Factor Reduce Skin Graft Applications in Patients with Diabetic Foot Ulcer?

BACKGROUND

Diabetic foot ulcer (DFU) is a serious health problem. Major amputation increases the risk of mortality in patients with DFU; therefore, treatment methods other than major amputation come to the fore for these patients. Graft applications create an appropriate environment for the reproduction of epithelial cells. Similarly, epidermal growth factor (EGF) also stimulates epithelization and increases epidermis formation. In this study, we aimed to compare patients with DFU treated with EGF and those treated with a split-thickness skin graft.

METHODS

Patients who were treated for DFU in the general surgery clinic were included in the study. The patients were evaluated retrospectively according to their demographic characteristics, wound characteristics, duration of treatment, and treatment modalities.

RESULTS

There were 26 patients in the EGF group and 21 patients in the graft group. The mean duration of treatment was 7 weeks (4-8 weeks) in the EGF group and 5.3 weeks (4-8 weeks) in the graft group (P < .05). In the EGF group, wound healing could not be achieved in one patient during the study period. In the graft group, no recovery was achieved in three patients (14.2%) in the donor site. Graft loss was detected in four patients (19%), and partial graft loss was observed in three patients (14.2%). The DFU of these patients were on the soles (85.7%). These patients have multiple comorbidities.

CONCLUSIONS

EGF application may be preferred to avoid graft complications in the graft area and the donor site, especially in elderly patients with multiple comorbidities and wounds on the soles.

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

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

Non-vascular contributing factors of diabetic foot ulcer severity in national referral hospital of Indonesia

PURPOSE

Diabetic foot ulcer (DFU) is a common chronic complication of type 2 diabetes mellitus (T2DM) in Indonesia, with a prevalence of 7.3%. However, the characteristics of these patients remain unclear. We investigated the characteristics of patients with DFU without peripheral arterial disease (PAD) and analyzed non-vascular factors related to severity of DFU in a tertiary care national referral hospital in Indonesia.

METHODS

This was a cross-sectional study including 123 hemodynamically stable DFU patients without PAD recruited from Dr. Cipto Mangunkusumo National General Hospital, Jakarta, Indonesia from 2010-2015.

RESULTS

DFU patients were predominantly over 50 years old (75.6%) and diagnosed with T2DM for 5 years with poor glycemic control (82.7%) and peripheral neuropathy (91.3%). Most patients had anemia (86.7%), leukocytosis (84.6%), and were undernourished, as characterized by a low lipid profile (90.8%) and hypoalbuminemia (83.7%). Most had extensive size of ulcer at the initial visit, with a median size of 16.23 (2.92-60.16) cm2. Ulcers were mostly located of the forefoot (62.5%) and were caused by mechanical trauma (46.2%). Bivariate analysis revealed that significant factors for the development of DFU were related to DFU size, including duration of T2DM (p = 0.04), leukocyte levels (p =  < 0.01), and thrombocyte levels (p =  < 0.01). Multivariate analysis showed leucocyte (p = 0.03) and thrombocyte (p = 0.023) had significantly correlated with DFU severity.

CONCLUSION

Leucocyte and thrombocyte may be the greatest contributing non-vascular factors for severity of DFU in Indonesia.

Correlation of MRSA polymerase chain reaction (PCR) wound swab testing and wound cultures in skin and soft tissue infections

Methicillin-resistant Staphylococcus aureus is a considerable pathogen in the setting of skin and soft tissue infections (SSTIs). MRSA PCR swab testing is widely used in the setting of respiratory tract infections, however little data exists relating to the use of MRSA PCR swab testing in SSTIs. Three thousand, nine hundred and ninety-five patients were included in this retrospective study that aimed to validate the clinical correlation of MRSA PCR wound swab testing in SSTIs through sensitivity, specificity, negative predictive value (NPV), and positive predictive value (PPV) analysis. From this review, MRSA PCR wound swabs were found to have a sensitivity of 97.6% (97.5-98.5), a specificity of 94.9% (94.3-95.7), a PPV of 92.3% (91.4-93.2), and a NPV of 98.4% (98.0-98.8). The study results demonstrate that the MRSA SSTI PCR assays have a high NPV and the potential to be a vital tool in de-escalating antimicrobial therapy associated with SSTIs.

The Effects of Silver-Releasing Foam Dressings on Diabetic Foot Ulcer Healing

Diabetic foot ulcers (DFUs) are a serious complication in diabetic patients and lead to high morbidity and mortality. Numerous dressings have been developed to facilitate wound healing of DFUs. This study investigated the wound healing efficacy of silver-releasing foam dressings versus silver-containing cream in managing outpatients with DFUs. Sixty patients with Wagner Grade 1 to 2 DFUs were recruited. The treatment group received silver-releasing foam dressing (Biatain^® Ag Non-Adhesive Foam dressing; Coloplast, Humlebaek, Denmark). The control group received 1% silver sulfadiazine (SSD) cream. The ulcer area in the silver foam group was significantly reduced compared with that in the SSD group after four weeks of treatment (silver foam group: 76.43 ± 7.41%, SSD group: 27.00 ± 4.95%, p < 0.001). The weekly wound healing rate in the silver foam group was superior to the SSD group during the first three weeks of treatment (p < 0.05). The silver-releasing foam dressing is more effective than SSD in promoting wound healing of DFUs. The effect is more pronounced in the initial three weeks of the treatment. Thus, silver-releasing foam could be an effective wound dressing for DFUs, mainly in the early period of wound management.

Silver Sulfadiazine Eradicates Antibiotic-Tolerant Staphylococcus aureus and Pseudomonas aeruginosa Biofilms in Patients with Infected Diabetic Foot Ulcers

Infections are among the most frequent and challenging events in diabetic foot ulcers (DFUs). Pathogenic bacteria growing in biofilms within host tissue are highly tolerant to environmental and chemical agents, including antibiotics. The present study was aimed at assessing the use of silver sulfadiazine (SSD) for wound healing and infection control in 16 patients with DFUs harboring biofilm-growing Staphylococcus aureus and Pseudomonas aeruginosa. All patients received a treatment based on a dressing protocol including disinfection, cleansing, application of SSD, and application of nonadherent gauze, followed by sterile gauze and tibio-breech bandage, in preparation for toilet surgery after 30 days of treatment. Clinical parameters were analyzed by the T.I.M.E. classification system. In addition, the activity of SSD against biofilm-growing S. aureus and P. aeruginosa isolates was assessed in vitro. A total of 16 patients with S. aureus and P. aeruginosa infected DFUs were included in the study. Clinical data showed a statistically significant (p < 0.002) improvement of patients’ DFUs after 30 days of treatment with SSD with significant amelioration of all the parameters analyzed. Notably, after 30 days of treatment, resolution of infection was observed in all DFUs. In vitro analysis showed that both S. aureus and P. aeruginosa isolates developed complex and highly structured biofilms. Antibiotic susceptibility profiles indicated that biofilm cultures were significantly (p ≤ 0.002) more tolerant to all tested antimicrobials than their planktonic counterparts. However, SSD was found to be effective against fully developed biofilms of both S. aureus and P. aeruginosa at concentrations below those normally used in clinical preparations (10 mg/mL). These results strongly suggest that the topical administration of SSD may represent an effective alternative to conventional antibiotics for the successful treatment of DFUs infected by biofilm-growing S. aureus and P. aeruginosa.

Comparison of Mortality Rate and Severity of Pulmonary Involvement in Coronavirus Disease-2019 Adult Patients With and Without Type 2 Diabetes: A Cohort Study

OBJECTIVES

Patients with diabetes are potentially at higher risk of mortality due to coronavirus disease-2019 (COVID-19). In this study, we aimed to compare the outcomes and severity of pulmonary involvement in COVID-19 patients with and without diabetes.

METHODS

In this cohort study, we recruited patients with diabetes who were hospitalized due to COVID-19 during the period from February 2020 to May 2020. Hospitalized individuals without diabetes were enrolled as control subjects. All patients were followed for 90 days and clinical findings and patients' outcomes were reported.

RESULTS

Over a period of 4 months, 127 patients with diabetes and 127 individuals without diabetes with a diagnosis of COVID-19 were recruited. Their mean age was 65.70±12.51 years. Mortality was higher in the group with diabetes (22.8% vs 15.0%; p=0.109), although not significantly. More severe pulmonary involvement (p=0.015), extended hospital stay (p<0.001) and greater need for invasive ventilation (p=0.029) were reported in this population. Stepwise logistic regression revealed that diabetes was not independently associated with mortality (p=0.092). Older age (odds ratio [OR], 1.054; p=0.003), aggravated pulmonary involvement on admission (OR, 1.149; p=0.001), presence of comorbidities (OR, 1.290; p=0.020) and hypothyroidism (OR, 6.576; p=0.021) were associated with mortality. Diabetic foot infection had a strong positive correlation with mortality (OR, 49.819; p=0.016), whereas insulin therapy had a negative correlation (OR, 0.242; p=0.045).

CONCLUSIONS

The mortality rate due to COVID-19 did not differ significantly between patients with or without diabetes. Older age, macrovascular complications and presence of comorbidities could increase mortality in people with diabetes. Insulin therapy during hospitalization could attenuate the detrimental effects of hyperglycemia and improve prognosis of patients with COVID-19 and diabetes.

Bacteriological profile and antibiotic susceptibility of diabetic Foot infections at Ribat University hospital; a retrospective study from Sudan

Purpose

Diabetic foot infection (DFI) is one of the most feared complications of diabetes. In Sudan, the number of cases and the problems associated with diabetic foot infections increased in recent years. This study aimed to assess the bacteriological profile of patients with DFIs and their antibiotic susceptibility pattern.

Methods

A descriptive retrospective cross-sectional study was carried out at Surgery Department of Ribat University Hospital. All medical records of patients with DFIs during the period from September 2017 to February 2019 were reviewed using data collection sheet. The collected data were analyzed using Statistical Package for Social Sciences.

Results

Out of 250 DFI patients, 73.2% of them were males, and 86.4% of them had type 2 diabetes mellitus, and most of them suffered from diabetes for more than 10 years. Regarding culture results, 64.7% and 35.3% of the samples revealed presence of single microorganism and mixed infections, respectively. A total of 335 bacterial isolates were identified, gram-negative were more prevalent than gram-positive organisms. The most frequently isolated organisms were Proteus spp. Staphylococcus aureus, and Escherichia coli. Furthermore, antibiotic susceptibility pattern showed that imipenem, amikacin and vancomycin have the highest activity against isolated bacteria, and all isolates were found to be completely resistant to different cephalosporin drugs.

Conclusion

Among the studied samples, gram-negative bacteria were found to be more common in DFI patients, Proteus spp. and S. aureus were the most common microorganisms. Moreover, different isolated microorganisms showed to have different degrees of resistance and sensitivity to various antibacterial drugs.

The TUDID Study - Background and Design of a Prospective Cohort

Prevalence of both type 1 and type 2 diabetes mellitus is growing worldwide and one major cause for morbidity and mortality. However, not every patient develops diabetes-related complications, but causes for the individual susceptibility are still not fully understood. As a platform to address this, we initiated the TUDID (TUebingen DIabetes Database) study, a prospective, monocentric, observational study that includes adults with diabetes mellitus who are treated in the inpatient clinic of a University Hospital in southern Germany. Besides a thorough clinical examination and extensive laboratory tests (with integrated biobanking), major study focuses are the kidneys, the eyes, the vasculature as well as cognition and mood where standardized investigations for early stages for diabetes complications are performed. Analyses of the data generated by this precise characterization of diabetes-related complications will contribute to our understanding of the development and course of such complications, and thus facilitate the implementation of tailored treatment options that can reduce the risk and severity of diabetes-related complications.

Association Between Serum 25-OH-Vitamin D and Diabetic Foot Ulcer in Patients With Type 2 Diabetes

Background: Vitamin D deficiency has been associated with an increased risk in several diabetic complications. We aimed to evaluate the association between vitamin D and diabetic foot ulcer (DFU) in patients with type 2 diabetes. Methods: Fifty one patients were included in the study and divided into two groups for study of vitamin D, cholesterol, and triglycerides in blood serum on DFU. The association between vitamin D and DFU was measured by binary logistic regression analysis. The cut point of vitamin D for DFU was assessed by the receiver operating characteristic curve. Results: Levels of 25-OH-vitamin D were lower in patients with DFU than in DM group (P < 0.0001). The AUC of 25-OH-vitamin D was 0.8254 and had an optimal cut point value (13.68 ng/ml) for the identification of DFU, with a sensitivity of 90% and a specificity of 66.67% in all patients. Multivariate logistic regression analysis indicated that the significant risk factors included 25-OH-vitamin D level (P = 0.001, OR = 0.618) and HDL-C level (P = 0.038, OR = 0.012). Conclusion: Low serum 25-OH-vitamin D level was associated with DFU. This indication was more specific than cholesterol and triglycerides levels.

Long Noncoding RNA GAS5 Regulates Macrophage Polarization and Diabetic Wound Healing

A central feature of diabetic (Db) wounds is the persistence of chronic inflammation, which is partly due to the prolonged presence of proinflammatory (M1) macrophages. Using in vivo and in vitro analyses, we have tested the hypothesis that long noncoding RNA GAS5 is dysregulated in Db wounds. We have assessed the contribution of GAS5 to the M1 macrophage phenotype, as well as the functional consequences of knocking down its expression. We found that expression of GAS5 is increased significantly in Db wounds and in cells isolated from Db wounds. Hyperglycemia induced GAS5 expression in macrophages in vitro. Overexpression of GAS5 in vitro promoted macrophage polarization toward an M1 phenotype by upregulating signal transducer and activator of transcription 1. Of most significance in our judgment, GAS5 loss-of-function enhanced Db wound healing. These data indicate that the relative level of long noncoding RNA GAS5 in wounds plays a key role in the wound healing response. Reductions in the levels of GAS5 in wounds appeared to enhance healing by promoting transition of M1 macrophages to M2 macrophages. Thus, our results suggest that targeting long noncoding RNA GAS5 may provide a therapeutic intervention for correcting impaired Db wound healing.

Methicillin-Resistant Staphylococcus aureus Diabetic Foot Crossed Infection: A Case Report

This work presents a protocol to prevent the transmission of multidrug-resistant infections. We focus on the Diabetic Foot Unit Podiatry Clinic Area attached to the University of Seville in particular. The most common complication for patients with diabetes is leg ulcers. Together with neuropathy, vasculopathy, and immunological response disorder, these individuals have a high predisposition to developing infections. Staphylococcus aureus is a highly prevalent microorganism in humans which, at times, may act as a pathogen. Due mainly to indiscriminate abuse of antibiotics, the methicillin-resistant strain known by its initials as MRSA is the most extended nosocomial infection globally and is a severe community and hospital healthcare problem. This paper describes compliance with new general recommendations on cleaning, hygiene, and decontamination, in addition to implementation of this specific protocol, after detection of cross infection (healthcare-related infection) in the studied unit in two patients with MRSA-infected ulcers. After an in-depth bibliographical review, strict hand hygiene measures and use of non-sterile gloves were used when treating all patients with a diabetic foot. Finally, we reflect on the need to educate healthcare personnel to guarantee correct prescription of selected antibiotics. The role of the podiatrist in the multidisciplinary team is highlighted not only in terms of management and treatment of lesions in diabetic patients, but also as a healthcare agent for the detection and prevention of MRSA together with other multidrug-resistant infections.