Diagnosis and management of infection in the diabetic foot

Bioactive poly(salicylic acid)-poly(citric acid) scaffolds improve diabetic wound repair via regulating HIF-1α, Nrf2 and macrophage

Diabetic wounds environment is over-oxidized, over-inflammatory, leading to difficulties in regenerating blood vessels, and retardation of healing in diabetic wounds. Therefore, diabetic wounds can be treated from the perspective of scavenging oxidative free radicals and reducing the level of inflammation. Herein, we report a bioactive poly(salicylic acid)-poly(citric acid) (FPSa-PCG) hydrogel for diabetic wound repair. The FPSa-PCG hydrogel shows abilities of antioxidation, anti-inflammation, and regulation of macrophage phenotype. The FPSa-PCG hydrogel showed good biocompatibility, and obtain the abilities of promotion of macrophages migration, reduction of ROS generation, suppression of the M1-type macrophage polarization. FPSa and PCG could synergistically enhance the angiogenesis through upregulating the mRNA expression of HIF1Α, VEGF, and CD31 in endothelial cells and reduce the ROS level of macrophages through upregulating the mRNA expression of Nrf2. The in vivo diabetic wound model confirmed the promoting effect of FPSa-PCG hydrogel on wound closure in diabetes. The further studies found that FPSa-PCG hydrogel could induce the CD31 protein expression in the subcutaneous tissue and inhibit the TNF-a protein expression. This work shows that the simple composition FPSa-PCG hydrogel has a promising therapeutic potential in the treatment of diabetic wounds.

Brazilian Society of Angiology and Vascular Surgery 2023 guidelines on the diabetic foot

The diabetic foot interacts with anatomical, vascular, and neurological factors that challenge clinical practice. This study aimed to compile the primary scientific evidence based on a review of the main guidelines, in addition to articles published on the Embase, Lilacs, and PubMed platforms. The European Society of Cardiology system was used to develop recommendation classes and levels of evidence. The themes were divided into six chapters (Chapter 1 - Prevention of foot ulcers in people with diabetes; Chapter 2 - Pressure relief from foot ulcers in people with diabetes; Chapter 3 -Classifications of diabetic foot ulcers; Chapter 4 - Foot and peripheral artery disease; Chapter 5 - Infection and the diabetic foot; Chapter 6 - Charcot's neuroarthropathy). This version of the Diabetic Foot Guidelines presents essential recommendations for the prevention, diagnosis, treatment, and follow-up of patients with diabetic foot, offering an objective guide for medical practice.

IWGDF/IDSA guidelines on the diagnosis and treatment of diabetes-related foot infections (IWGDF/IDSA 2023)

The International Working Group on the Diabetic Foot (IWGDF) has published evidence-based guidelines on the management and prevention of diabetes-related foot diseases since 1999. The present guideline is an update of the 2019 IWGDF guideline on the diagnosis and management of foot infections in persons with diabetes mellitus. The Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) framework was used for the development of this guideline. This was structured around identifying clinically relevant questions in the P(A)ICO format, determining patient-important outcomes, systematically reviewing the evidence, assessing the certainty of the evidence, and finally moving from evidence to the recommendation. This guideline was developed for healthcare professionals involved in diabetes-related foot care to inform clinical care around patient-important outcomes. Two systematic reviews from 2019 were updated to inform this guideline, and a total of 149 studies (62 new) meeting inclusion criteria were identified from the updated search and incorporated in this guideline. Updated recommendations are derived from these systematic reviews, and best practice statements made where evidence was not available. Evidence was weighed in light of benefits and harms to arrive at a recommendation. The certainty of the evidence for some recommendations was modified in this update with a more refined application of the GRADE framework centred around patient important outcomes. This is highlighted in the rationale section of this update. A note is also made where the newly identified evidence did not alter the strength or certainty of evidence for previous recommendations. The recommendations presented here continue to cover various aspects of diagnosing soft tissue and bone infections, including the classification scheme for diagnosing infection and its severity. Guidance on how to collect microbiological samples, and how to process them to identify causative pathogens, is also outlined. Finally, we present the approach to treating foot infections in persons with diabetes, including selecting appropriate empiric and definitive antimicrobial therapy for soft tissue and bone infections; when and how to approach surgical treatment; and which adjunctive treatments may or may not affect the infectious outcomes of diabetes-related foot problems. We believe that following these recommendations will help healthcare professionals provide better care for persons with diabetes and foot infections, prevent the number of foot and limb amputations, and reduce the patient and healthcare burden of diabetes-related foot disease.

Clinical practice recommendations for infectious disease management of diabetic foot infection (DFI) - 2023 SPILF

In march 2020, the International Working Group on the Diabetic Foot (IWGDF) published an update of the 2015 guidelines on the diagnosis and management of diabetic foot infection (DFI). While we (the French ID society, SPILF) endorsed some of these recommendations, we wanted to update our own 2006 guidelines and specifically provide informative elements on modalities of microbiological diagnosis and antibiotic treatment (especially first- and second-line regiments, oral switch and duration). The recommendations put forward in the present guidelines are addressed to healthcare professionals managing patients with DFI and more specifically focused on infectious disease management of this type of infection, which clearly needs a multidisciplinary approach. Staging of the severity of the infection is mandatory using the classification drawn up by the IWGDF. Microbiological samples should be taken only in the event of clinical signs suggesting infection in accordance with a strict preliminarily established protocol. Empirical antibiotic therapy should be chosen according to the IWGDF grade of infection and duration of the wound, but must always cover methicillin-sensitive Staphylococcus aureus. Early reevaluation of the patient is a fundamental step, and duration of antibiotic therapy can be shortened in many situations. When osteomyelitis is suspected, standard foot radiograph is the first-line imagery examination and a bone biopsy should be performed for microbiological documentation. Histological analysis of the bone sample is no longer recommended. High dosages of antibiotics are recommended in cases of confirmed osteomyelitis.

Concomitants of Diabetic Foot Ulcer - A Review

BACKGROUND

Diabetes mellitus leading to foot ulcer is a serious complication, and it is considered a global epidemic. Neuropathyand high blood glucose levels are the primary causes of foot ulcers. Fifteen percent of people with diabetes develop foot ulcers, and these foot disorders are the main cause of lower extremity amputation among such patients.

INTRODUCTION

Complications of diabetic foot, affecting the lower extremities are common and quite complex and life-threatening. This review focuses on the life-threatening factors associated with diabetic foot ulcers and also the diagnosing and preventive measures. Neuropathy assessment and the range of foot ulcers were accurately examined.

CONCLUSION

Novel therapies focusing on the vascularity of the lower limbs, infection control, and ischemic control are being developed to mainly treat nonhealing ulcers.

IWGDF/IDSA Guidelines on the Diagnosis and Treatment of Diabetes-related Foot Infections (IWGDF/IDSA 2023)

The International Working Group on the Diabetic Foot (IWGDF) has published evidence-based guidelines on the management and prevention of diabetes-related foot diseases since 1999. The present guideline is an update of the 2019 IWGDF guideline on the diagnosis and management of foot infections in persons with diabetes mellitus. The Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) framework was used for the development of this guideline. This was structured around identifying clinically relevant questions in the P(A)ICO format, determining patient-important outcomes, systematically reviewing the evidence, assessing the certainty of the evidence, and finally moving from evidence to the recommendation. This guideline was developed for healthcare professionals involved in diabetes-related foot care to inform clinical care around patient-important outcomes. Two systematic reviews from 2019 were updated to inform this guideline, and a total of 149 studies (62 new) meeting inclusion criteria were identified from the updated search and incorporated in this guideline. Updated recommendations are derived from these systematic reviews, and best practice statements made where evidence was not available. Evidence was weighed in light of benefits and harms to arrive at a recommendation. The certainty of the evidence for some recommendations was modified in this update with a more refined application of the GRADE framework centred around patient important outcomes. This is highlighted in the rationale section of this update. A note is also made where the newly identified evidence did not alter the strength or certainty of evidence for previous recommendations. The recommendations presented here continue to cover various aspects of diagnosing soft tissue and bone infections, including the classification scheme for diagnosing infection and its severity. Guidance on how to collect microbiological samples, and how to process them to identify causative pathogens, is also outlined. Finally, we present the approach to treating foot infections in persons with diabetes, including selecting appropriate empiric and definitive antimicrobial therapy for soft tissue and bone infections; when and how to approach surgical treatment; and which adjunctive treatments may or may not affect the infectious outcomes of diabetes-related foot problems. We believe that following these recommendations will help healthcare professionals provide better care for persons with diabetes and foot infections, prevent the number of foot and limb amputations, and reduce the patient and healthcare burden of diabetes-related foot disease.

Dressings and topical agents containing hyaluronic acid for chronic wound healing

BACKGROUND

Hyaluronic acid is synthesised in plasma membranes and can be found in extracellular tissues. It has been suggested that the application of hyaluronic acid to chronic wounds may promote healing, and the mechanism may be due to its ability to maintain a moist wound environment which helps cell migration in the wound bed.

OBJECTIVES

To evaluate the effects of hyaluronic acid (and its derivatives) on the healing of chronic wounds.

SEARCH METHODS

We used standard, extensive Cochrane search methods. The latest search date was February 2022.

SELECTION CRITERIA

We included randomised controlled trials that compared the effects of hyaluronic acid (as a dressing or topical agent) with other dressings on the healing of pressure, venous, arterial, or mixed-aetiology ulcers and foot ulcers in people with diabetes.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures expected by Cochrane. We assessed the certainty of the evidence using the GRADE approach.

MAIN RESULTS

We included 12 trials (13 articles) in a qualitative synthesis, and were able to combine data from four trials in a quantitative analysis. Overall, the included trials involved 1108 participants (mean age 69.60 years) presenting 178 pressure ulcers, 54 diabetic foot ulcers, and 896 leg ulcers. Sex was reported for 1022 participants (57.24% female). Pressure ulcers It is uncertain whether there is a difference in complete healing (risk ratio (RR) 1.17, 95% confidence interval (CI) 0.58 to 2.35); change in ulcer size (mean difference (MD) 25.60, 95% CI 6.18 to 45.02); or adverse events (none reported) between platelet-rich growth factor (PRGF) + hyaluronic acid and PRGF because the certainty of evidence is very low (1 trial, 65 participants). It is also uncertain whether there is a difference in complete healing between lysine hyaluronate and sodium hyaluronate because the certainty of evidence is very low (RR 2.50, 95% CI 0.71 to 8.83; 1 trial, 14 ulcers from 10 participants). Foot ulcers in people with diabetes It is uncertain whether there is a difference in time to complete healing between hyaluronic acid and lyophilised collagen because the certainty of evidence is very low (MD 16.60, 95% CI 7.95 to 25.25; 1 study, 20 participants). It is uncertain whether there is a difference in complete ulcer healing (RR 2.20, 95% CI 0.97 to 4.97; 1 study, 34 participants) or change in ulcer size (MD -0.80, 95% CI -3.58 to 1.98; 1 study, 25 participants) between hyaluronic acid and conventional dressings because the certainty of evidence is very low. Leg ulcers We are uncertain whether there is a difference in complete wound healing (RR 0.98, 95% CI 0.26 to 3.76), percentage of adverse events (RR 0.79, 95% CI 0.22 to 2.80), pain (MD 2.10, 95% CI -5.81 to 10.01), or change in ulcer size (RR 2.11, 95% CI 0.92 to 4.82) between hyaluronic acid + hydrocolloid and hydrocolloid because the certainty of evidence is very low (1 study, 125 participants). It is uncertain whether there is a difference in change in ulcer size between hyaluronic acid and hydrocolloid because the certainty of evidence is very low (RR 1.02, 95% CI 0.84 to 1.25; 1 study, 143 participants). We are uncertain whether there is a difference in complete wound healing between hyaluronic acid and paraffin gauze because the certainty of evidence is very low (RR 2.00, 95% CI 0.21 to 19.23; 1 study, 24 ulcers from 17 participants). When compared with neutral vehicle, hyaluronic acid probably improves complete ulcer healing (RR 2.11, 95% CI 1.46 to 3.07; 4 studies, 526 participants; moderate-certainty evidence); may slightly increase the reduction in pain from baseline (MD -8.55, 95% CI -14.77 to -2.34; 3 studies, 337 participants); and may slightly increase change in ulcer size, measured as mean reduction from baseline to 45 days (MD 30.44%, 95% CI 15.57 to 45.31; 2 studies, 190 participants). It is uncertain if hyaluronic acid alters incidence of infection when compared with neutral vehicle (RR 0.89, 95% CI 0.53 to 1.49; 3 studies, 425 participants). We are uncertain whether there is a difference in change in ulcer size (cm2) between hyaluronic acid and dextranomer because the certainty of evidence is very low (MD 5.80, 95% CI -10.0 to 21.60; 1 study, 50 participants). We downgraded the certainty of evidence due to risk of bias or imprecision, or both, for all of the above comparisons. No trial reported health-related quality of life or wound recurrence. Measurement of change in ulcer size was not homogeneous among studies, and missing data precluded further analysis for some comparisons.

AUTHORS' CONCLUSIONS

There is currently insufficient evidence to determine the effectiveness of hyaluronic acid dressings in the healing of pressure ulcers or foot ulcers in people with diabetes. We found evidence that hyaluronic acid probably improves complete ulcer healing and may slightly decrease pain and increase change in ulcer size when compared with neutral vehicle. Future research into the effects of hyaluronic acid in the healing of chronic wounds should consider higher sample size and blinding to minimise bias and improve the quality of evidence.

Imaging of the Diabetic Foot

Diabetic foot complications are increasingly prevalent in the world, leading to significant morbidity and driving up associated health care costs. Complex pathophysiology and suboptimal specificity of current imaging modalities have made diagnosis challenging, mainly in the evaluation of superimposed foot infection to underlying arthropathy or other marrow lesions. Recent advances in radiology and nuclear medicine have the potential to streamline the assessment of diabetic foot complications. But we must be aware of the specific strengths and weaknesses of each modality, and their applications. This review offers a comprehensive approach to the spectrum of diabetic foot complications and their imaging appearances in conventional and advanced imaging studies, including optimal technical considerations for each technique. Advanced magnetic resonance imaging (MRI) techniques are highlighted, illustrating their complementary role to conventional MRI, in particular their potential impact in avoiding additional studies.

The association between bacteria and outcome and the influence of sampling method, in people with a diabetic foot infection

Purpose

Different bacteria lead to divers diabetic foot infections (DFIs), and some bacteria probably lead to higher amputation and mortality risks. We assessed mortality and amputation risk in relation to bacterial profiles in people DFI and investigated the role of sampling method.

Methods

We included people (> 18 years) with DFI in this retrospective study (2011–2020) at a Dutch tertiary care hospital. We retrieved cultures according to best sampling method: (1) bone biopsy; (2) ulcer bed biopsy; and (3) swab. We aggregated data into a composite determinant, consisting of unrepeated bacteria of one episode of infection, clustered into 5 profiles: (1) Streptococcus and Staphylococcus aureus; (2) coagulase-negative Staphylococcus, Cutibacterium, Corynebacterium and Enterococcus; (3) gram-negative; (4) Anaerobic; and (5) less common gram-positive bacteria. We calculated Hazard Ratio’s (HR’s) using time-dependent-Cox regression for the analyses and investigated effect modification by sampling method.

Results

We included 139 people, with 447 person-years follow-up and 459 episodes of infection. Sampling method modified the association between bacterial profiles and amputation for profile 2. HR’s (95% CI’s) for amputation for bacterial profiles 1–5: 0.7 (0.39–1.1); stratified analysis for profile 2: bone biopsy 0.84 (0.26–2.7), ulcer bed biopsy 0.89 (0.34–2.3), swab 5.9*(2.9–11.8); 1.3 (0.78–2.1); 1.6 (0.91–2.6); 1.6 (0.58–4.5). HR’s (95% CI’s) for mortality for bacterial profiles 1–5: 0.89 (0.49–1.6); 0.73 (0.38–1.4); 2.6*(1.4–4.8); 1.1(0.58–2.2); 0.80(0.19–3.3).

Conclusions

In people with DFI, there was no association between bacterial profiles in ulcer bed and bone biopsies and amputation. Only in swab cultures, low-pathogenic bacteria (profile 2), were associated with a higher amputation risk. Infection with gram-negative bacteria was associated with a higher mortality risk. This study underlined the possible negative outcome of DFI treatment based on swabs cultures.

Neuropathic ulcers in leprosy: clinical features, diagnosis and treatment

Leprosy is a neglected disease caused by Mycobacterium leprae and Mycobacterium lepromatosis, and is related to significant disabilities resulting from the neural damage generated by this mycobacteria. Neuropathic ulcers-lesions that can appear at the plantar and extra-plantar levels-are one such disability, and diagnosis requires an adequate dermatological, neurological and microbiological evaluation. The treatment of these lesions is based on a multidisciplinary approach that includes debridement of the necrotic tissue, controlling infections, reducing pressure areas, optimising blood flow, and nerve decompression. This review aims to describe the clinical features, diagnostic methods and treatment of neuropathic ulcers in leprosy. The diagnostic methods and medical management used in leprosy ulcers are based on those used for diabetic foot. This requires radical change as these diseases are immunologically and physiologically very different.

Accelerative Effect of Cinnamon Nanoparticles as well as HAMLET on Healing of Wounds Infected with MRSA in Diabetic Rats

Objective

The aim of the present study was to investigate the effect of cinnamon nanoparticles (CNPs) on healing of wounds infected with methicillin-resistant Staphylococcus aurous with human alpha-lactalbumin made lethal to tumor cells sensitization in diabetic rats.

Methods

We included fifty diabetic male rats and divided them into 5 groups. There were 10 rats in each group as follows: CONTROL group: we did not infect the CONTROL group. The wound was only covered with sterile saline 0.9% solution (0.1 mL). INFCTD group: in this group, the wounds were infected with MRSA and covered with sterile saline 0.9% solution (0.1 mL). INFCTD-HMLT group: in this group, the wounds were infected with MRSA and HAMLET (100 μg). INFCTD-CNM group: in this group, the wounds were infected with MRSA and 0.1 mL CNPs (1 mg/mL) were applied topically to wounds. INFCTD-HMLT-CNM group: in this group, the wounds were infected with MRSA, HAMLET (100 μg), and 0.1 mL CNPs (1 mg/mL).

Results

Bacteriology, wound area reduction measurements, biochemistry, histomorphometrical studies, hydroxyproline levels, and reverse transcription polymerase chain reaction for caspase-3, Bcl-2, and p53 showed significant difference between rats in the INFCTD-HMT-CNM group in comparison with other groups (P < 0.05).

Conclusions

Accelerated healing of diabetic wounds infected with MRSA showed that local application of cinnamon nanoparticles along with HAMLET sensitization on S. aureus-infected wound could be taken into consideration.

Microbial Infection and Antibiotic Susceptibility of Diabetic Foot Ulcer in China: Literature Review

OBJECTIVE

To investigate the microbial spectrum isolated from foot ulcers among diabetic patients in China, which was conducted to help clinicians choose optimal antibiotics empirically.

METHOD

The PubMed, MEDLINE, Web of Science, China Biology Medicine (CBM), China National Knowledge Infrastructure (CNKI), WanFang, and VIP databases were searched for studies published between 2015 to 2019, that report primary data on diabetic foot infection (DFI) and antibiotic susceptibility in China.

RESULT

A total of 63 articles about DFI and antibiotic susceptibility tests among diabetic patients in China were included. There were 11,483 patients with an average age of 60.2 ± 10.1 years and a mean course of 10.6 ± 5.0 years between 2010 and 2019, covering most geographical regions of China. The prevalence of Gram-positive (GP) bacteria (43.4%) was lower than that of Gram-negative (GN) (52.4%). The most prevalent pathogens isolated were Staphylococcus aureus (17.7%), Escherichia coli (10.9%), Pseudomonas aeruginosa (10.5%), Klebsiella pneumoniae (6.2%), Staphylococcus epidermidis (5.3%), Enterococcus faecalis (4.9%), and fungus (3.7%). The prevalence of polymicrobial infection was 22.8%. GP bacteria were sensitive to linezolid, vancomycin, and teicoplanin. More than 50% of GN bacteria were resistant to third-generation cephalosporins, while the resistance rates of piperacillin/tazobactam, amikacin, meropenem, and imipenem were relatively low. Among the 6017 strains of the isolated organisms, 20% had multi-drug resistance (MDR). Staphylococcus aureus (30.4%) was the most predominant MDR bacteria, followed by extended-spectrum β-lactamase (ESBL) (19.1%).

CONCLUSION

The microbial infection of foot ulcers among diabetic patients in China is diverse. The microbial spectrum is different in different geographic regions and Staphylococcus aureus is the predominant bacteria. Polymicrobial and MDR bacterial infections on the foot ulcers are common. This study could be valuable in guiding the empirical use of antibiotics for diabetic foot infections.

Recent advances in the local antibiotics delivery systems for management of osteomyelitis

Chronic osteomyelitis is a challenging disease due to its serious rates of mortality and morbidity while the currently available treatment strategies are suboptimal. In contrast to the adopted systemic treatment approaches after surgical debridement in chronic osteomyelitis, local drug delivery systems are receiving great attention in the recent decades. Local drug delivery systems using special carriers have the pros of enhancing the feasibility of penetration of antimicrobial agents to bone tissues, providing sustained release and localized concentrations of the antimicrobial agents in the infected area while avoiding the systemic side effects and toxicity. Most important, the incorporation of osteoinductive and osteoconductive materials in these systems assists bones proliferation and differentiation, hence the generation of new bone materials is enhanced. Some of these systems can also provide mechanical support for the long bones during the healing process. Most important, if the local systems are designed to be injectable to the affected site and biodegradable, they will reduce the level of invasion required for implantation and can win the patients’ compliance and reduce the healing period. They will also allow multiple injections during the course of therapy to guard against the side effect of the long-term systemic therapy. The current review presents different available approaches for delivering antimicrobial agents for the treatment of osteomyelitis focusing on the recent advances in researches for local delivery of antibiotics.

HIGHLIGHTS

Chronic osteomyelitis is a challenging disease due to its serious mortality and morbidity rates and limited effective treatment options.

Local drug delivery systems are receiving great attention in the recent decades.

Osteoinductive and osteoconductive materials in the local systems assists bones proliferation and differentiation

Local systems can be designed to provide mechanical support for the long bones during the healing process.

Designing the local system to be injectable to the affected site and biodegradable will reduces the level of invasion and win the patients’ compliance.

Enhanced autophagy promotes the clearance of Pseudomonas aeruginosa in diabetic rats with wounds

Background

To investigate the effects of the Pseudomonas aeruginosa (P. aeruginosa) type 3 secretion system (T3SS) on diabetic wound healing and autophagy-associated proteins.

Methods

P. aeruginosa and P. aeruginosa without T3SS were used to infect back wounds in 36 rats (18 normal and 18 diabetic). Followed infection with P. aeruginosa, another 36 rats (18 normal and 18 diabetic) with back wounds were treated with autophagy inducer rapamycin or gentamicin (positive control). Wound healing, colony count, HE and Masson staining were recorded. Western blot and immunofluorescent were used to determine the expression of the autophagy markers (LC3, beclin-1 and p62) in wound tissues.

Results

The number of P. aeruginosa colonies in infected wounds began to decrease on day 3 in normal rats and on day 7 in diabetic rats. The decrease was more apparent in P. aeruginosa without T3SS. The expression of LC3-II/LC3-I and beclin-1 gradually increased, and p62 gradually decreased in the wounds in of all groups; however, the changes were more dramatic in normal rats compared with diabetic rats on day 14. Rapamycin increased LC3-II/LC3-I and beclin-1 expression, and decreased p62 expression, gentamicin had no effect on their expression of autophagy markers.

Conclusions

T3SS of P. aeruginosa inhibited the entire autophagy process in wounds. Thus inducing autophagy could enhance the clearance of P. aeruginosa in diabetic wounds and is expected to become a new method of anti-P. aeruginosa infection.

Multidisciplinary Approach for the Management and Treatment of Diabetic Foot Infections with a Resorbable, Gentamicin-Loaded Bone Graft Substitute

Diabetic patients are at increased risk of developing foot ulcers which may cause bone infections associated with a high probability of both amputation and mortality. Therefore, prompt diagnosis and adequate treatment are of key importance. In our Diabetic Foot Unit, effective multidisciplinary treatment of osteomyelitis secondary to diabetes involves the application of a gentamicin-eluting calcium sulphate/hydroxyapatite bone graft substitute to fill residual bone voids after debridement. The data of all patients treated with the gentamicin-eluting calcium sulphate/hydroxyapatite bone graft substitute for diabetic foot infections with ulcer formation and osteomyelitis at metatarsals, calcaneus and hindfoot at our institute from July 2013 to September 2016 were retrospectively collected and evaluated. A total of 35 patients were included in this retrospective single-arm case series and were either continuously followed up for at least one year or until healing was confirmed. Nineteen lesions affected the distal row of tarsus/talus, ten the calcaneus and a further six were located at the metatarsals. While all of the metatarsal lesions had healed at 1-year follow-up, the healing rate in the hindfoot region was lower with 62.5% at the calcaneus and 72.2% at the distal tarsus and talus at 12 months, respectively. The overall cure rate for ulcerous bone infection was 81.3%. In two calcaneal lesions (25%) and two lesions of distal tarsus/talus (11.1%) amputation was considered clinically necessary. Promising results were achieved in the treatment of diabetic foot infections with soft tissue ulcers by a multidisciplinary approach involving extensive debridement followed by adequate dead space management with a resorbable gentamicin-eluting bone graft substitute.

Hydrocolloid dressing improves wound healing by increasing M2 macrophage polarization in mice with diabetes

Impaired wound healing is one of the most common complications of diabetes, and is known to be caused by multiple complicated factors. For instance, impaired angiogenesis, neuropathy, and hyperglycemia all function to delay subsequent wound closure. Alternatively, moist wound healing, which provides an appropriate environment for wounds, was reported to permit rapid healing by managing wound exudate. Accordingly, wound dressing materials that facilitate moist healing have been developed. The present study sought to clarify the effects of wound dressing material for moist healing of diabetic wounds, in terms of the dynamics of angiogenic factors and macrophages, using a mouse model of naturally occurring diabetes. Wounds with full-thickness skin defects were inflicted on the backs of mice and covered with dressing materials of hydrogel or gauze (control), which were retained for 3, 5, 7, 10, or 14 days following wound generation. During this time, the localization of neutrophils, fibroblasts and macrophages as well as the expression of vascular endothelial growth factor (VEGF) in the wounds and surrounding areas was observed each day. Healing clearly occurred in the hydrogel group with an increase in neutrophils and the angiogenic factor, VEGF. Moreover, the use of hydrogel resulted in a rapid rise in M1 macrophages, which appeared in the early stage of the injury, as well as rapid subsequent appearance of M2 macrophages. Thus, herein, we demonstrate that the formation of a moist environment via wound dressing material effectively improves diabetic wound healing.

Infrared thermography for monitoring severity and treatment of diabetic foot infections

Monitoring of diabetic foot infections is largely based on clinical assessment, which is limited by moderate reliability. We conducted a prospective study to explore monitoring of thermal asymmetry (difference between mean plantar temperature of the affected and unaffected foot) for the assessment of severity of diabetic foot infections. In patients with moderate or severe diabetic foot infections (International Working Group on the Diabetic Foot infection-grades 3 or 4) we measured thermal asymmetry with an advanced infrared thermography setup during the first 4-5 days of in-hospital treatment, in addition to clinical assessments and tests of serum inflammatory markers (white blood cell counts and C-reactive protein levels). We assessed the change in thermal asymmetry from baseline to final assessment, and investigated its association with infection-grades and serum inflammatory markers. In seven included patients, thermal asymmetry decreased from median 1.8°C (range: -0.6 to 8.4) at baseline to 1.5°C (range: -0.1 to 5.1) at final assessment (P = 0.515). In three patients who improved to infection-grade 2, thermal asymmetry at baseline (median 1.6°C (range: -0.6 to 1.6)) and final assessment (1.5°C (range: 0.4 to 5.1)) remained similar (P = 0.302). In four patients who did not improve to infection-grade 2, thermal asymmetry decreased from median 4.3°C (range: 1.8 to 8.4) to 1.9°C (range: -0.1 to 4.4; P = 0.221). No correlations were found between thermal asymmetry and infection-grades (r = -0.347; P = 0.445), CRP-levels (r = 0.321; P = 0.482) or WBC (r = -0.250; P = 0.589) during the first 4-5 days of hospitalization. Based on these explorative findings we suggest that infrared thermography is of no value for monitoring diabetic foot infections during in-hospital treatment.

Microbiologic characteristics and antibiotic resistance rates of diabetic foot infections

PURPOSE

the purpose of this research was to identify the sociodemographic and microbiological characteristics and antibiotic resistance rates of patients with diabetic foot infections, hospitalized in an emergency reference center.

METHODS

it was an observational and transversal study. The sociodemographic data were collected by direct interview with the patients. During the surgical procedures, specimens of tissue of the infected foot lesions were biopsied to be cultured, and for bacterial resistance analysis.

RESULTS

the sample consisted of 105 patients. The majority of patierns were men, over 50 years of age, married and with low educational level. There was bacterial growth in 95 of the 105 tissue cultures. In each positive culture only one germ was isolated. There was a high prevalence of germs of the Enterobacteriaceae family (51,5%). Gram-negative germs were isolated in 60% of cultures and the most individually isolated germs were the Gram-positive cocci, Staphylococcus aureus (20%) and Enterococcus faecalis (17,9%). Regarding antibiotic resistance rates, a high frequency of Staphylococcus aureus resistant to methicillin (63,0%) and to ciprofloxacin (55,5%) was found; additionally, 43,5% of the Gram-negative isolated germs were resistant to ciprofloxacin.

CONCLUSIONS

the majority of patients were men, over 50 years of age, married and with low educational level. The most prevalent isolated germs from the infected foot lesions were Gram-negative bacteria, resistant to ciprofloxacin, and the individually most isolated germ was the methicillin resistant Staphylococcus aureus.

Curcumin Nanoparticles Improved Diabetic Wounds Infected With Methicillin-Resistant Staphylococcus aureus Sensitized With HAMLET

Accurately orchestrated course of events normally observed in healing are not followed in diabetic wounds, and bacterial colonization/infection further messes up the process. Novel therapeutic options for treatment of infections caused by multidrug-resistant Staphylococcus aureus are urgently needed. HAMLET (human α-lactalbumin made lethal to tumor cells) has been reported to be able to sensitize bacterial pathogens to traditional antimicrobial agents. The aim was to assess the wound healing activity of curcumin nanoparticles in diabetic wounds infected with methicillin-resistant Staphylococcus aureus (MRSA) sensitized with HAMLET. Fifty male rats were randomized into 5 groups of 10 animals each. In CONTROL group, 0.1-mL sterile saline 0.9% solution was added to the wounds with no infection. In MRSA group, the wounds were infected with MRSA and only treated with 0.1-mL sterile saline 0.9% solution. In MRSA/HAMLET group, infected wounds were treated with HAMLET (100 µg). In MRSA/CNP group, animals with infected wounds were treated with 0.1 mL topical application of 1 mg/mL curcumin nanoparticles. In MRSA/CNP/HAMLET group, animals with infected wounds were treated with topical application of 0.1 mL solution of curcumin nanoparticles (1 mg/mL) and HAMLET (100 µg). All test formulations were applied for 10 days, twice a day, starting from first treatment. Microbiological examination; planimetric, biochemical, histological, and quantitative morphometric studies; immunohistochemical staining for angiogenesis; determination of hydroxyproline levels; and reverse transcription polymerase chain reaction for caspase 3, Bcl-2, and p53 showed that there was significant difference between animals in MRSA/CNP/HAMLET group compared with other groups (P < .05). Curcumin nanoparticles improved diabetic wounds infected with MRSA sensitized with HAMLET and had the potential to offer more attention to this safer agent for topical use in infected diabetic wounds.

[Complex treatment of patients with pyo-necrotic complications of the neuropathic form of diabetic foot syndrome]

OBJECTIVE

Of study is improving the results of treatment of patients with pyo-necrotic complications of diabetic foot syndrome by including the method of negative pressure wound treatment in the complex treatment program in combination with using of the combined antibacterial drug Cifran ST and immunocorrective therapy.

MATERIAL AND METHODS

The results of examination and treatment of 184 patients with pyo-necrotic complications of the neuropathic form of diabetic foot syndrome were analyzed. According to choice of treatment methods in the postoperative period all patients were divided into two groups. In 95 patients (group I), iodine-containing ointments based on polyethylene glycol were used for local treatment of purulent foot wounds and standard systemic antibacterial therapy was performed. In 89 patients (group II), negative pressure wound treatment (NPWT) was used to treat wounds in the postoperative period. In addition to standard parenteral antimicrobial therapy, these patients also received an oral combined antibacterial drug Cifran ST and immunocorrective cytokine therapy (Leukinferon). The analysis of the dynamics of the wound process was carried out based on the clinical picture and the results of cytological, bacteriological and immunological studies of the wound exudate.

RESULTS

The presented strategy of complex treatment of pyo-necrotic complications of the neuropathic form of diabetic foot syndrome allowed group II patients to significantly reduce the degree of microbial contamination of wounds, to achieve a faster regression of the content of proinflammatory and inflammatory cytokines in the wound exudate, as well as to reduce the time of wound cleansing and the transition of the pyo-necrotic process to the reparative stage in comparison with group I patients. This allowed group II patients to reduce the time of plastic closure of the wound from 24.3±0.5 to 15.6±1.7 days, to avoid generalization of infection, death and high level amputation of the limb. At the same time, 11.6% of patients in group I had high level limb amputation due to generalization of infection. The mortality rate in group I was 5.3%.

CONCLUSIONS

Adding of vacuum therapy of wounds, systemic antimicrobial therapy using the combined antibacterial drug Cifran ST and immunocorrective cytokine therapy in the complex treatment program for patients with neuropathic form of diabetic foot syndrome after radical surgical treatment of the pyo-necrotic lesion allows reducing the time of wound cleansing and the transition of the pyo-necrotic process to the reparative stage. On the other hand, this makes it possible for this category of patients to perform plastic closure of the wound at an earlier date, avoid generalization of infection and high level amputation of the limb.

A novel intraoperative technique seeding morselized bone tissue into pediatric blood culture bottles improves microbiological diagnosis in patients with foot and ankle osteomyelitis

BACKGROUND

Osteomyelitis, particularly cases involving the foot and ankle, is a challenging situation that frequently leads to amputations and major sequelae. Targeted antibiotics treating an identified pathogen are key to a successful outcome; however, traditional culture methods for bone tissue have poor sensitivity. This study prospectively compared a novel method for obtaining and processing infected bone tissue with the standard technique.

METHODS

107 patients presenting with a diagnosis of osteomyelitis of the foot and ankle between 2008 and 2017 were prospectively included. Diagnosis was done according to clinical, laboratory and imaging findings. We obtained paired samples of bone tissue from all patients; they were processed through a usual culture method (UCM), but they were also morselized and seeded into pediatric blood culture bottles (PBCBs). We compared the culture yield and the number of agents detected using both the McNemar and the Mann-Whitney tests, respectively.

RESULTS

We studied 107 patients (63 with diabetic foot infection and 44 with nondiabetic osteomyelitis). The causative agent was identified in 60.7% of cases using the UCM and in 97.2% of cases using PBCBs (p < 0.001). We detected a mean of 1.05 ± 1.03 bacteria using the UCM and 1.67 ± 0.92 bacteria using PBCBs (p < 0.01).

CONCLUSION

Cultures using morselized bone seeded in PBCBs identified the causative agent in a significantly larger percentage than the UCM. Additionally, this method identified a larger number of pathogen agents. A better agent identification method has advantages such as identifying more specific antibiotic treatment in these cases.

Guidelines on the diagnosis and treatment of foot infection in persons with diabetes (IWGDF 2019 update)

The International Working Group on the Diabetic Foot (IWGDF) has published evidence-based guidelines on the prevention and management of diabetic foot disease since 1999. This guideline is on the diagnosis and treatment of foot infection in persons with diabetes and updates the 2015 IWGDF infection guideline. On the basis of patient, intervention, comparison, outcomes (PICOs) developed by the infection committee, in conjunction with internal and external reviewers and consultants, and on systematic reviews the committee conducted on the diagnosis of infection (new) and treatment of infection (updated from 2015), we offer 27 recommendations. These cover various aspects of diagnosing soft tissue and bone infection, including the classification scheme for diagnosing infection and its severity. Of note, we have updated this scheme for the first time since we developed it 15 years ago. We also review the microbiology of diabetic foot infections, including how to collect samples and to process them to identify causative pathogens. Finally, we discuss the approach to treating diabetic foot infections, including selecting appropriate empiric and definitive antimicrobial therapy for soft tissue and for bone infections, when and how to approach surgical treatment, and which adjunctive treatments we think are or are not useful for the infectious aspects of diabetic foot problems. For this version of the guideline, we also updated four tables and one figure from the 2016 guideline. We think that following the principles of diagnosing and treating diabetic foot infections outlined in this guideline can help clinicians to provide better care for these patients.

Molecular Imaging of Diabetic Foot Infections: New Tools for Old Questions

Diabetic foot infections (DFIs) are a common, complex, and costly medical problem with increasing prevalence. Diagnosing DFIs is a clinical challenge due to the poor specificity of the available methods to accurately determine the presence of infection in these patients. However, failure to perform an opportune diagnosis and provide optimal antibiotic therapy can lead to higher morbidity for the patient, unnecessary amputations, and increased healthcare costs. Novel developments in bacteria-specific molecular imaging can provide a non-invasive assessment of the infection site to support diagnosis, determine the extension and location of the infection, guide the selection of antibiotics, and monitor the response to treatment. This is a review of recent research in molecular imaging of infections in the context of DFI. We summarize different clinical and preclinical methods and the translational implications aimed to improve the care of patients with DFI.

Bacteriology of moderate-to-severe diabetic foot infections in two tertiary hospitals of Iran

BACKGROUND

Approximately 25% of people with diabetes will experience diabetic foot ulcers (DFUs) during their lifetime. The present study was designed to determine the type of microorganisms isolated from the DFUs and their antibiotic resistance pattern, and to determine predisposing factors contributing to antibiotic resistance at the authors' wound care clinic in Qazvin, Iran.

METHODS

A cross-sectional study was conducted from May to December 2017. One specimen for microbiological studies was obtained from the deep tissue. All demographic, clinical, and laboratory data and results of ulcer culture were collected for each case. Antimicrobial susceptibility testing to different agents was carried out using the disc diffusion method. A p value < 0.05 was considered significant.

RESULTS

95 aerobic microorganisms were isolated from 105 specimens. Among Gram-positive and negative bacteria, Staphylococcus spp. and Escherichia (E). coli were the most frequent organisms isolated, respectively. Multidrug resistant (MDR) organisms constituted up to 48.4%, with 37.5% of isolated Enterococcus spp. being VRE, 48.8% of Staphylococcus spp. being methicillin-resistant, 77.8% of isolated E. coli being ESBL and 66.7% of isolated Pseudomonas being MDR. The minimum and maximum prevalence of resistance in Gram-negative bacteria were 17.6% and 87.5% for imipenem and ceftazidime, respectively. The prevalence of Gram-negative bacilli was higher in older patients (p value = 0.039) and rose markedly in patients with a higher number of hospitalizations (p value = 0.015).

CONCLUSION

Due to emergence of antibiotic resistance pathogens, culture specimens and antibiotic sensitivity testing are essential for correct management of the DFU infections and the selection of appropriate antibiotics.

Cutaneous Wound Healing in Diabetic Mice Is Improved by Topical Mineralocorticoid Receptor Blockade

Skin ulcers resulting from impaired wound healing are a serious complication of diabetes. Unresolved inflammation, associated with the dysregulation of both the phenotype and function of macrophages, is involved in the poor healing of diabetic wounds. Here, we report that topical pharmacological inhibition of the mineralocorticoid receptor (MR) by canrenoate or MR small interfering RNA can resolve inflammation to improve delayed skin wound healing in diabetic mouse models; importantly, wounds from normal mice are unaffected. The beneficial effect of canrenoate is associated with an increased ratio of anti-inflammatory M2 macrophages to proinflammatory M1 macrophages in diabetic wounds. Furthermore, we show that MR blockade leads to downregulation of the MR target, LCN2, which may facilitate macrophage polarization toward the M2 phenotype and improve impaired angiogenesis in diabetic wounds. Indeed, diabetic LCN2-deficient mice showed improved wound healing associated with macrophage M2 polarization and angiogenesis. In addition, recombinant LCN2 protein prevented IL-4-induced macrophage switch from M1 to M2 phenotype. In conclusion, topical MR blockade accelerates skin wound healing in diabetic mice via LCN2 reduction, M2 macrophage polarization, prevention of inflammation, and induction of angiogenesis.

Effects of Chitosan/Nano Selenium Biofilm on Infected Wound Healing in Rats; An Experimental Study

Objective

The present study was aimed at assessment of effect of application of Chitosan/Nano Selenium biofilm on infected wound healing in rats.

Methods

Sixty-eight male Wistar rats were randomized into four groups of 17 animals each. In group I (Normal) the wounds were created with no infection. In group II (MRSA), the wounds were infected with methicillin resistant Staphylococcus aureus (MRSA). In group III (MRSA/CHIT), animals with infected wounds were dressed with chitosan biofilm only. In group IV (MRSA/CHIT/NS), animals with infected wounds were dressed with Chitosan/Nano Selenium biofilm.

Results

There were significant differences in comparisons of group IV and other groups, particularly in terms of cellular infiltration and neovascularization. During the study period, scores for neovascularization was significantly higher in group IV rats than other groups (P<0.05). Polymorphonuclear (PMN) and mononuclear (MNC) cell count and fibroblast cell proliferation in group IV were significantly higher than those of other experimental groups (P<0.05).

Conclusion

Chitosan/Nano Selenium biofilm resulted in significant improvement in histopathological indices in full thickness infected wound healing.

Effect of negative-pressure wound therapy on the circulating number of peripheral endothelial progenitor cells in diabetic patients with mild to moderate degrees of ischaemic foot ulcer

Objective

To investigate the effect of negative-pressure wound therapy (NPWT) on the circulating number of endothelial progenitor cells (EPCs) in diabetic patients with mild to moderate degrees of ischemic foot ulcer.

Methods

We selected 84 diabetic patients who had a foot ulcer with a duration of at least four weeks and who had an ankle-brachial index of 0.5–0.9. Patients were assigned to one two groups according to 2:1 randomization: NPWT group ( n = 56) and non-NPWT (patients who did not receive NPWT) group ( n = 28). The control group (NC group) was composed of 18 patients who had normal glucose tolerance and lower extremity ulcer without arteriovenous disease. NPWT was performed on the ulcer after debridement for one week for patients in both the NPWT group and the NC group, and the patients in the non-NPWT group received conventional treatment process. The circulating number of EPCs was measured before and after various treatments, and the factors influencing their changes were analysed.

Results

After NPWT, the circulating number of EPCs significantly increased in both the NPWT group and the NC group ((85.3 ± 18.1) vs. (34.1 ± 12.5)/106 cells; (119.9 ± 14.4) vs. (66.1 ± 10.6)/106 cells, both P < 0.05). In contrast, the circulating number of EPCs had no significant change in the non-NPWT group ((45.2 ± 19.4) vs. (34.7 ± 16.8)/106 cells, P > 0.05). In addition, the circulating levels of vascular endothelial growth factor (VEGF) and the protein expressions of VEGF and stromal cell-derived factor-1α (SDF-1α) in the granulation tissue significantly increased after NPWT in both the NPWT and the NC group, but there was no significant change in the non-NPWT group. Compared with the non-NPWT group, the changes in VEGF and SDF-1α levels in the sera and granulation tissue were all significantly higher in both the NPWT and NC groups ( P < 0.05, P < 0.01, respectively). There was no significant difference in changes in the circulating number of EPCs in the peripheral blood and levels of VEGF and SDF-1α in the sera and granulation tissue between the NPWT and NC groups. Correlation analysis showed that the change in the circulating number of EPCs was correlated with the changes of VEGF and SDF-1α levels in the sera and granulation of the NPWT and NC groups ( P < 0.05).

Conclusion

NPWT may increase the circulating number of EPCs in diabetic patients with mild to moderate ischaemic foot ulcer as in non-diabetic controls, which may be attributed to the upregulation of systemic and local VEGF and SDF-1α levels.

[Prevention and treatment of infectious diseases in diabetic patients]

The bidirectional relationship between infectious diseases and diabetes is well-known. On the one hand, diabetes patients are at a higher risk of presenting with infectious diseases, possibly with more severity, and on the other hand, infectious diseases impair metabolic control in patients with diabetes. Population ageing arises partly due to an increased survival rate in chronic diseases, of which diabetes is amongst them. Improving infectious disease prevention could reduce complications arising from the former diseases, consequences of decompensated diabetes condition (morbidity, incapacity, hospital admissions, healthcare costs, and mortality rates) and result in improved quality of life in patients with diabetes. The current review presents the treatment of infectious diseases in patients with diabetes and the dealing with immuno-preventable diseases with the currently advised vaccinations.

Evaluation of antibiotic activity of methicillin in healing of full-thickness infected wounds with sensitized methicillin resistant Staphylococcus aureus in the presence of HAMLET

OBJECTIVES

The novel healing choices for handling of infections due to multidrug resistant Staphylococcus aureus are reguired. HAMLET has been reported to be able to sensitize bacterial pathogens to traditional antimicrobial agents. The aim was to assess wound healing activity of methicillin in presence of HAMLET in methicillin resistant S. aureus (MRSA) infected wounds.

MATERIALS AND METHODS

Fifty male rats were randomized into five groups of ten animals each. In CONTROL group, 0.1 ml sterile saline 0.9% solution was added to the wounds with no infection. In MRSA group, the wounds were infected with MRSA and only treated with 0.1 ml the sterile saline (0.9%) solution. In MRSA/HAMLET group, infected wounds were cured with HAMLET (100 µg). In group MRSA/ Met, animals with infected wounds were cured with 0.1 ml local use of 1 mg/ml methicillin. In MRSA/Met/HAMLET group, animals with infected wounds were cured with local use of 0.1 ml solution of methicillin (1 mg/ml) and HAMLET (100 µg). All test formulations were used for ten consecutive days, twice a day, beginning from first treatment.

RESULTS

Microbiological examination, planimetric, histological and quantitative morphometric studies, immunohistochemical staining for angiogenesis, determination of hydroxyproline levels and RT-PCR for Caspase 3, Bcl-2 and p53 showed that there was significant difference between animals in MRSA/Met/ HAMLET group compared to other groups (P<0.05).

CONCLUSION

HAMLET could make methicillin beneficial for handling of MRSA infected wounds and had the prospective effect to consider this harmless agent for local application.

Diagnosis and treatment of necrotising otitis externa and diabetic foot osteomyelitis - similarities and differences

OBJECTIVE

Necrotising otitis externa is a severe inflammatory process affecting soft tissue and bone, mostly in diabetic patients. Diabetic patients are also at risk of diabetic foot osteomyelitis, another inflammatory condition involving soft tissue and bone. This review aimed to describe the similarities and differences of these entities in an attempt to further advance the management of necrotising otitis externa.

METHOD

A PubMed search was conducted using the key words 'otitis externa', 'necrotising otitis externa', 'malignant otitis externa', 'osteomyelitis' and 'diabetic foot'.Results and conclusionThe similarities regarding patient population and pathophysiology between necrotising otitis externa and diabetic foot osteomyelitis raise basic questions concerning the effects of long-standing diabetes on the external ear. The concordance between local swabs and bone cultures in diabetic foot osteomyelitis is less than 50 per cent. If this holds true also to necrotising otitis externa, the role of deep tissue cultures should be strongly considered. Similar to diabetic foot osteomyelitis, magnetic resonance imaging should be considered in selected necrotising otitis externa subgroups.

Diabetic Foot Infections: Update on Management

PURPOSE OF REVIEW

Diabetic foot infections (DFIs) are common in patients with diabetes mellitus complicated by foot ulcers and can be classified in different categories based on their severity. In this report, we present the diagnosis and management of DFIs according to their classification.

RECENT FINDINGS

While appropriate antibiotic regiments and surgical techniques for the treatment of DFIs are well established, new technologies and techniques for example in medical imaging, wound care modalities, and supplementary therapy approaches show potentially promising results in preventing DFIs. As with every complex disease, fine tuning DFI management can be challenging as it requires careful evaluation of different parameters. It demands timely action, close collaboration of different specialties, and patient cooperation.

Is it necessary to change instruments between sampling sites when taking multiple tissue specimens in musculoskeletal infections?

Introduction Surgical debridement of orthopaedic infections allows biopsy for microbiology and facilitates successful treatment. It is recommended that biopsy instruments are changed when taking multiple samples. This study compared assessed cross-contamination between biopsy sites when using same instruments to take tissue samples from multiple sites. Materials and methods During the surgical debridement, we defined five sampling sites and marked them with diathermy. Two sampling techniques were performed on same patient to minimise any potential bias arising from the type of host and the severity of infection. First, fresh instruments were used for each biopsy site. Titleond, the instruments used in the first sampling site were reused to take samples from the remaining sites. By comparing the microbiology results of the samples taken by each technique for each site we determined cross-contamination with microorganisms. Results Fifteen patients with foot and ankle infections (mean age 56 years) were included. Ten patients were diabetic and five had neuropathies. Cross-contamination between sampling sites occurred in eight cases when the same instruments were used to take biopsies (P = 0.002, Fisher's exact test). One or more microorganisms were involved in cross-contamination and the latter always occurred between two consecutive sites rather than sites that were further apart. Conclusion It is important to use fresh instruments for each biopsy site when taking multiple samples in musculoskeletal infection as cross-contamination might occur otherwise and affect microbiological studies.

Lower-Extremity Osteomyelitis Treatment Using Calcium Sulfate/Hydroxyapatite Bone Void Filler with Antibiotics Seven-Year Retrospective Study

BACKGROUND

Over a 74-month period (∼6 years), 143 lower-extremity osteomyelitis locations in 125 patients were treated with a calcium sulfate/hydroxyapatite liquid bone void filler with antibiotic(s).

METHODS

The osteomyelitis locations were treated with a percutaneous antibiotic delivery technique delivering intraosseous antibiotic followed by either oral or intravenous antibiotics for 4 weeks.

RESULTS

There was no recurrence of osteomyelitis in 96.15% of the treatable patients. Outcomes classified by the Cierny-Mader clinical classification are discussed as well.

CONCLUSIONS

A bone void filler with antibiotic(s) using the percutaneous antibiotic delivery technique is a safe, reliable, and effective means to treat lower-extremity osteomyelitis with either oral or intravenous antibiotics for 4 weeks.

Wound healing related agents: Ongoing research and perspectives

Wound healing response plays a central part in chronic inflammation, affecting millions of people worldwide. It is a dynamic process that can lead to fibrosis, if tissue damage is irreversible and wound resolution is not attained. It is clear that there is a tight interconnection among wound healing, fibrosis and a variety of chronic disease conditions, demonstrating the heterogeneity of this pathology. Based on our further understanding of the cellular and molecular mechanisms underpinning tissue repair, new therapeutic approaches have recently been developed that target different aspects of the wound healing process and fibrosis. Nevertheless, several issues still need to be taken into consideration when designing modern wound healing drug delivery formulations. In this review, we highlight novel pharmacological agents that hold promise for targeting wound repair and fibrosis. We also focus on drug-delivery systems that may enhance current and future therapies.

Microbiology and Antimicrobial Therapy for Diabetic Foot Infections

In addition to being the prime factor associated with amputation, diabetic foot infections (DFIs) are associated with major morbidity, increasing mortality, and reduced quality of life. The choice of appropriate antibiotics is very important in order to reduce treatment failure, antimicrobial resistance, adverse events, and costs. We reviewed articles on microbiology and antimicrobial therapy and discuss antibiotic selection in Korean patients with DFIs. Similar to Western countries, Staphylococcus aureus is the most common pathogen, with Streptococcus, Enterococcus, Enterobacteriaceae and Pseudomonas also prevalent in Korea. It is recommended that antibiotics are not prescribed for clinically uninfected wounds and that empirical antibiotics be selected based on the clinical features, disease severity, and local antimicrobial resistance patterns. Narrow-spectrum oral antibiotics can be administered for mild infections and broad-spectrum parenteral antibiotics should be administered for some moderate and severe infections. In cases with risk factors for methicillin-resistant S. aureus or Pseudomonas, empirical antibiotics to cover each pathogen should be considered. The Health Insurance Review and Assessment Service standards should also be considered when choosing empirical antibiotics. In Korea, nationwide studies need to be conducted and DFI guidelines should be developed.

IL-33 improves wound healing through enhanced M2 macrophage polarization in diabetic mice

IL-33 is a newly discovered member of the IL-1 family and has been identified as a potent inducer of Th2 type immunity. Emerging evidence imply that IL-33 may also act as an alarm to alert the immune system when released by epithelial barrier tissues during trauma or infection. In this study, we further investigate the potential efficacy of IL-33 on dermal wound healing in streptozotocin-induced diabetic mice. A full-thickness skin wound was generated on the back of diabetic mice and treated with IL-33 or vehicle topically. Our data showed that IL-33 delivery contributed to diabetic wound closure with wounds gaping narrower and exhibiting elevated re-epithelialization. IL-33 promoted the new extracellular matrix (ECM) deposition and angiogenesis formation, which indicates an important role of IL-33 on matrix synthesis and neovascularization. Meanwhile, IL-33 accelerated the development of M2 macrophages in wound sites in vivo, and amplified IL-13-induced polarization of bone marrow-derived macrophages toward a M2 phenotype in vitro. Furthermore, IL-33-amplified M2 macrophages augmented the proliferation of fibroblasts and ECM deposition. All together, these results strongly suggest manipulation of IL-33-mediated signal might be a potential therapeutic approach for diabetic skin wounds.

Nonsurgical Treatment of Osteomyelitis of the Hallux Sesamoids: A Case Series and Literature Review

The aim of the present study was to determine the effectiveness of nonsurgical treatment for osteomyelitis of the hallucal sesamoids. Osteomyelitis of the hallucal sesamoids in young and healthy patients is rare and might originate from hematogenous spread or after a puncture wound. In diabetic patients with peripheral neuropathy, it often results from direct contiguous seeding from adjacent ulceration. The superiority of surgical versus nonsurgical therapy is still debated. In our institution, all patients presenting with osteomyelitis of the hallucal sesamoids are first treated nonsurgically but eventually usually require a surgical procedure. We reviewed 18 patients with a clinical and radiologic diagnosis of osteomyelitis of the hallucal sesamoids treated in our institution during a 13-year period (from January 2000 to December 2012). The inclusion criteria were a signal alteration on magnetic resonance imaging or bone lesions on computed tomography or conventional radiographs, combined with a deep ulcer with a positive probe-to-bone test. Nonsurgical therapy consisted of frequent wound treatment, immobilization, offloading in a cast or other orthotic device, and oral antibiotics. Of the 18 patients, 11 had diabetes, 16 had peripheral neuropathy, 11 had peripheral arterial disease, and 5 had immunosuppression. After a period of nonsurgical therapy ranging from 4 weeks to 9 months, 15 of 18 patients required surgical excision, internal resection, or amputation. In this patient population, we no longer consider nonsurgical therapy a viable option. Patients should be advised, before starting nonsurgical treatment, that the therapy will be long and demanding and very often results in a surgical procedure.

Expression and Influence of Matrix Metalloproteinase–9/Tissue Inhibitor of Metalloproteinase–1 and Vascular Endothelial Growth Factor in Diabetic Foot Ulcers

A high matrix metalloproteinase–9/tissue inhibitor of metalloproteinase–1 (MMP9/TIMP1) ratio is associated with poor ulcer healing, yet how the ratio of MMP9/TIMP1 changes in diabetic foot ulcers (DFUs) with infection and how these changes may affect wound healing remain unclear. Therefore, the objective of this investigation was to explore relationships among the MMP9/TIMP1 ratio, infection, and DFUs. After being informed of the details of this study, 32 patients signed consent forms. Skin biopsies were performed for all patients. Wound tissues were obtained from all patients with wounds, and healthy skin samples were collected from patients without wounds during orthopedic surgery. Microbial cultures were obtained using the samples from diabetic patients with wounds. All patients were divided into 4 groups according to colony-forming units (CFUs) per gram of tissue (>1 × 106 or <1 × 106): group A (diabetic wounds with high quantities of bacteria), group B (diabetic wounds with low quantities of bacteria), group C (diabetic patients without wounds), and group D (nondiabetic patients with wounds). In addition, the biopsies were evaluated by both reverse transcription–quantitative polymerase chain reaction and Western blotting to assess the levels of MMP9, TIMP1, and vascular endothelial growth factor (VEGF). The results show that for both mRNA and protein, expression of MMP9 (fold change 1.14 ± 0.12 vs 0.60 ± 0.08 vs 0.39±0.09 vs 0.13 ± 0.06, P < .01) decreased, whereas that of TIMP1 (1.01 ± 0.09 vs 2.86 ± 0.85 vs 4.88 ± 0.83 vs 7.29 ± 1.55, P < .01) and VEGF (1.01 ± 0.22 vs 3.55 ± 0.97 vs 5.72 ± 0.55 vs 6.92 ± 1.55, P < .01) increased from group A to group D. These results suggest that an increase in the MMP9/TIMP1 ratio in infected DFUs may induce a decrease in VEGF expression.

Diabetic Foot Infections: an Update in Diagnosis and Management

Foot infections are a common problem in patients with diabetes and a risk factor for limb amputation. They occur as a result of skin ulceration, which facilitates penetration of pathogens to deeper tissues. The diagnosis of infection is clinical. Aerobic gram-positive cocci are the most common pathogens. Ulcers which are chronic, preceded by administration of antibiotics and hospitalization or complicated by severe infection are polymicrobial. Antibiotic therapy is initially empiric based on the severity of the infection. Definitive therapy is modified according to the results of the microbiological culture and the response to empiric treatment. The optimal duration of antibiotic therapy ranges from 1-2 weeks for mild infections to 2-4 weeks and even longer for severe infections and osteomyelitis. Surgical consultation should be sought for infections complicated with abscesses, necrotizing fasciitis or osteomyelitis. With appropriate care, infection resolves in about 80-90% of non-limb threatening and in about 60% of severe infections.

Awareness of diabetic foot disease amongst patients with type 2 diabetes mellitus attending the chronic outpatients department at a regional hospital in Durban, South Africa

Background

Diabetic foot disease (DFD) is a major challenge for the healthcare system, with enormous economic consequences for people living with diabetes, their families, and society, affecting both quality of life and quality of care. The study aim was to assess the level of awareness of DFD amongst patients with type 2 diabetes mellitus (T2DM).

Methods

An observational descriptive cross-sectional study was conducted at the chronic outpatients department of a regional hospital in Durban, South Africa.

Results

Two hundred participants with T2DM participated in the study. Ninety-one per cent of participants were either overweight or obese. Ninety-two per cent of participants had concomitant hypertension (57.5%), dyslipidaemia (26.7%) and eye disease (7.2%). Seventy-six per cent reported altered sensation in their lower limbs, and 90% reported having no previous DFD education. Only 22.2% of participants reported having examined their feet, but only when they experienced a problem. Participants achieved mediocre scores for knowledge (mean 4.45, standard deviation (s.d.) 2.201, confidence interval (CI) 4.2–4.7) and practice (mean 11.09, s.d. 2.233, CI 10.8–11.5) on diabetic foot care (DFC). Those who had a higher level of education and who were less than 65 years old had a significantly better score for previous foot care education (p <0.05).

Conclusion

The study demonstrated that awareness of DFD was suboptimal, based on current DFC guidelines. To minimise the burden of DFD, improved screening and prevention programmes as well as patient education should be provided to T2DM patients, whilst maintaining an aggressive approach to risk factor modifications, footwear and identifying the at-risk foot.

Bulgecin A as a β-lactam enhancer for carbapenem-resistant Pseudomonas aeruginosa and carbapenem-resistant Acinetobacter baumannii clinical isolates containing various resistance mechanisms

Genetic screening of Pseudomonas aeruginosa (PSDA) and Acinetobacter baumannii (ACB) reveals genes that confer increased susceptibility to β-lactams when disrupted, suggesting novel drug targets. One such target is lytic transglycosylase. Bulgecin A (BlgA) is a natural product of Pseudomonas mesoacidophila and a lytic transglycosolase inhibitor that works synergistically with β-lactams targeting PBP3 for Enterobacteriaceae. BlgA also weakly inhibits di-Zn²⁺ metallo-β-lactamases like L1 of Stenotrophomonas maltophilia. We hypothesized that because of its unique mechanism of action, BlgA could restore susceptibility to carbapenems in carbapenem-resistant PSDA (CR-PSDA) and carbapenem-resistant ACB, as well as ACB resistant to sulbactam. A BlgA-containing extract was prepared using a previously published protocol. CR-PSDA clinical isolates demonstrating a variety of carbapenem resistance mechanisms (VIM-2 carbapenemases, efflux mechanisms, and AmpC producer expression) were characterized with agar dilution minimum inhibitory concentration (MIC) testing and polymerase chain reaction. Growth curves using these strains were prepared using meropenem, BlgA extract, and meropenem plus BlgA extract. A concentrated Blg A extract combined with low concentrations of meropenem, was able to inhibit the growth of clinical strains of CR-PSDA for strains that had meropenem MICs ≥8 mg/L by agar dilution, and a clinical strain of an OXA-24 producing ACB that had a meropenem MIC >32 mg/L and intermediate ampicillin/sulbactam susceptibility. Similar experiments were conducted on a TEM-1 producing ACB strain resistant to sulbactam. BlgA with ampicillin/sulbactam inhibited the growth of this organism. As in Enterobacteriaceae, BlgA appears to restore the efficacy of meropenem in suppressing the growth of CR-PSDA and carbapenem-resistant ACB strains with a variety of common carbapenem resistance mechanisms. BlgA extract also inhibits VIM-2 β-lactamase in vitro. BlgA may prove to be an exciting adjunctive compound to extend the life of carbapenems against these vexing pathogens.

Treatment of bone marrow lesions (bone marrow edema)

Bone marrow lesions (BMLs) or using older terminology 'Bone marrow edema' is characterised by excessive water signals in the marrow space on magnetic resonance imaging or ultrasound; BMLs constitute a central component of a wide variety of inflammatory and non-inflammatory rheumatologic conditions affecting the musculoskeletal system: BMLs are not only considered significant sources of pain but also linked to increased disease activity in many musculoskeletal conditions (for example, osteoarthritis, rheumatoid arthritis). The purpose of this review is to summarise current knowledge about the treatment of BMLs, with an emphasis on the clinical and histological features of this entity in inflammatory and non-inflammatory disease. We also try to pair this hypothesis with the apparent beneficial effects of various treatment regimens, mainly within the group of bone antiresorptive drugs (calcitonin, bisphosphonates) on symptoms associated with BMLs.

Conservative treatment in a patient with diabetic osteomyelitis: antibiotic treatment is sufficient for complete bone regeneration in selected cases

Diabetic foot ulcers are commonly complicated by bone involvement and osteomyelitis. Diagnosing diabetic osteomyelitis can be problematic. However, positive findings at clinical examination and X-ray may set the diagnosis. Recent guidelines suggest that selected cases of diabetic osteomyelitis can be treated conservatively with antibiotics. We report on the successful treatment of a 52-year-old man with diabetes with osteomyelitis in the distal phalanx of a toe. On X-ray, the affected phalanx appeared completely eroded. However, regeneration of the bone tissue was observed following outpatient treatment with antibiotics. We therefore encourage doctors to provide conservative treatment for selected cases of diabetic osteomyelitis.

Phages targeting infected tissues: novel approach to phage therapy

While the true efficacy of phage therapy still requires formal confirmation in clinical trials, it continues to offer realistic potential treatment in patients in whom antibiotics have failed. Novel developments and approaches are therefore needed to ascertain that future clinical trials would evaluate the therapy in its optimal form thus allowing for reliable conclusions regarding the true value of phage therapy. In this article, we present our vision to develop and establish a bank of phages specific to most threatening pathogens and armed with homing peptides enabling their localization in infected tissues in densities assuring efficient and stable eradication of infection.