Evaluating diagnostic tools, outcome measures and antibiotic approach in diabetic foot osteomyelitis: a scoping review and narrative synthesis

INTRODUCTION

Diabetic foot osteomyelitis (DFO) is a significant complication of diabetic foot disease; however, diagnosis remains challenging and treatment success is difficult to ascertain. Literature in this space that has utilized varying diagnostic criteria and ideal outcome measures for success is unclear.

AREAS COVERED

This scoping review assesses methods of diagnosis of DFO and definitions of treatment outcomes in the literature assessing antibiotic therapy for treatment of DFO.

EXPERT OPINION

There is a lack of consensus in the design of diabetic foot trials, resulting in difficulty for clinicians to assess and manage serious conditions such as DFO. The cure for DFO is challenging to ascertain and treatment failure may be a better approach to assess outcomes in research assessing the efficacy of antibiotic therapy. In the absence of gold-standard diagnostic tools, practical approaches to outcome assessment may allow for greater clinical applicability of available data.

Magnetic Resonance Imaging and 99Tc WBC-SPECT/CT Scanning in Differential Diagnosis between Osteomyelitis and Charcot Neuroarthropathy: A Case Series

BACKGROUND

Distinguishing between Charcot Neuroarthropathy (CN), osteomyelitis (OM), and CN complicated with superimposed OM in diabetic patients is crucial for the treatment choice. Given that current diagnostic methods lack specificity, advanced techniques, e.g., magnetic resonance imaging (MRI) and 99mTc-HMPAO-WBC Single Photon Emission Computed Tomography (SPECT/CT), are needed. This study addresses the challenges in distinguishing OM and CN.

METHODS

We included diabetic patients with CN and soft tissue ulceration. MRI and 99mTc-HMPAO-WBC SPECT/CT were used for the diagnosis. The patients were classified into three probability levels for OM (i.e., Definite, Probable, and Unlikely) according to the Consensus Criteria for Diabetic Foot Osteomyelitis (CC-DFO).

RESULTS

Eight patients met the eligibility criteria. MRI, supported by SPECT-CT and CC-DFO, showed consistency with the OM diagnosis in three cases. The key diagnostic features included the location of signal abnormalities and secondary features such as skin ulcers, sinus tracts, and abscesses. Notably, cases with inconclusive MRI were clarified by SPECT/CT, emphasizing its efficacy in challenging scenarios.

CONCLUSIONS

The primary objective of this study was to compare the results of MRI and 99mTc-HMPAO-WBC SPECT/CT with the CC-DFO score in the diabetic foot with CN and suspected OM. Advanced imaging offers a complementary approach to distinguish between CN and OM. This can help delineate the limits of the disease for presurgical planning. While MRI is valuable, 99mTc-HMPAO-WBC SPECT/CT provides additional clarity, especially in challenging cases or when metallic implants affect MRI accuracy.

Diagnostic imaging of the diabetic foot: an EANM evidence-based guidance

PURPOSE

Consensus on the choice of the most accurate imaging strategy in diabetic foot infective and non-infective complications is still lacking. This document provides evidence-based recommendations, aiming at defining which imaging modality should be preferred in different clinical settings.

METHODS

This working group includes 8 nuclear medicine physicians appointed by the European Association of Nuclear Medicine (EANM), 3 radiologists and 3 clinicians (one diabetologist, one podiatrist and one infectious diseases specialist) selected for their expertise in diabetic foot. The latter members formulated some clinical questions that are not completely covered by current guidelines. These questions were converted into statements and addressed through a systematic analysis of available literature by using the PICO (Population/Problem-Intervention/Indicator-Comparator-Outcome) strategy. Each consensus statement was scored for level of evidence and for recommendation grade, according to the Oxford Centre for Evidence-Based Medicine (OCEBM) criteria.

RESULTS

Nine clinical questions were formulated by clinicians and used to provide 7 evidence-based recommendations: (1) A patient with a positive probe-to-bone test, positive plain X-rays and elevated ESR should be treated for presumptive osteomyelitis (OM). (2) Advanced imaging with MRI and WBC scintigraphy, or [18F]FDG PET/CT, should be considered when it is needed to better evaluate the location, extent or severity of the infection, in order to plan more tailored treatment. (3) In a patient with suspected OM, positive PTB test but negative plain X-rays, advanced imaging with MRI or WBC scintigraphy + SPECT/CT, or with [18F]FDG PET/CT, is needed to accurately assess the extent of the infection. (4) There are no evidence-based data to definitively prefer one imaging modality over the others for detecting OM or STI in fore- mid- and hind-foot. MRI is generally the first advanced imaging modality to be performed. In case of equivocal results, radiolabelled WBC imaging or [18F]FDG PET/CT should be used to detect OM or STI. (5) MRI is the method of choice for diagnosing or excluding Charcot neuro-osteoarthropathy; [18F]FDG PET/CT can be used as an alternative. (6) If assessing whether a patient with a Charcot foot has a superimposed infection, however, WBC scintigraphy may be more accurate than [18F]FDG PET/CT in differentiating OM from Charcot arthropathy. (7) Whenever possible, microbiological or histological assessment should be performed to confirm the diagnosis. (8) Consider appealing to an additional imaging modality in a patient with persisting clinical suspicion of infection, but negative imaging.

CONCLUSION

These practical recommendations highlight, and should assist clinicians in understanding, the role of imaging in the diagnostic workup of diabetic foot complications.

Clinical characteristics and outcomes associated with culture-negative status in limb osteomyelitis patients

Aims

This study aimed to investigate the clinical characteristics and outcomes associated with culture-negative limb osteomyelitis patients.

Methods

A total of 1,047 limb osteomyelitis patients aged 18 years or older who underwent debridement and intraoperative culture at our clinic centre from 1 January 2011 to 31 December 2020 were included. Patient characteristics, infection eradication, and complications were analyzed between culture-negative and culture-positive cohorts.

Results

Of these patients, 264 (25.2%) had negative cultures. Patients with a culture-negative compared with a culture-positive status were more likely to have the following characteristics: younger age (≤ 40 years) (113/264 (42.8%) vs 257/783 (32.8%); p = 0.004), a haematogenous aetiology (75/264 (28.4%) vs 150/783 (19.2%); p = 0.002), Cierny-Mader host A (79/264 (29.9%) vs 142/783 (18.1%); p < 0.001), antibiotic use before sampling (34/264 (12.9%) vs 41/783 (5.2%); p＜0.001), fewer taken samples (n＜3) (48/264 (18.2%) vs 60/783 (7.7%); p＜0.001), and less frequent presentation with a sinus (156/264 (59.1%) vs 665/783 (84.9%); p < 0.001). After initial treatments of first-debridement and antimicrobial, infection eradication was inferior in culture-positive osteomyelitis patients, with a 2.24-fold increase (odds ratio 2.24 (95% confidence interval 1.42 to 3.52)) in the redebridement rate following multivariate analysis. No statistically significant differences were found in long-term recurrence and complications within the two-year follow-up.

Conclusion

We identified several factors being associated with the culture-negative result in osteomyelitis patients. In addition, the data also indicate that culture negativity is a positive prognostic factor in early infection eradication. These results constitute the basis of optimizing clinical management and patient consultations.

Vascular Disease and Diabetes

The most important vascular lesion associated with diabetes is arteriosclerosis obliterans (ASO). Differential diagnosis from diabetic foot lesions that produce neurogenic ulcers is important, and the presence of ischemia must be diagnosed as soon as possible. It has been reported that diabetes makes ASO more severe and often leads to lower extremity amputation. In addition to the need for appropriate early control of diabetes, vascular surgeons are required to perform immediate revascularization in cases of ulcer and necrosis, and to aggressively use surgical treatment with good long-term prognosis. (This is a translation of Jpn J Vasc Surg 2023; 32: 105-109.).

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.

Does PAD and microcirculation status impact the tissue availability of intravenously administered antibiotics in patients with infected diabetic foot? Results of the DFIATIM substudy

Aims/hypothesis

The aim of this substudy (Eudra CT No:2019-001997-27)was to assess ATB availability in patients with infected diabetic foot ulcers(IDFUs)in the context of microcirculation and macrocirculation status.

Methods

For this substudy, we enrolled 23 patients with IDFU. Patients were treated with boluses of amoxicillin/clavulanic acid(AMC)(12patients) or ceftazidime(CTZ)(11patients). After induction of a steady ATB state, microdialysis was performed near the IDFU. Tissue fluid samples from the foot and blood samples from peripheral blood were taken within 6 hours. ATB potential efficacy was assessed by evaluating the maximum serum and tissue ATB concentrations(Cmax and Cmax-tissue)and the percentage of time the unbound drug tissue concentration exceeds the minimum inhibitory concentration (MIC)(≥100% tissue and ≥50%/60% tissue fT>MIC). Vascular status was assessed by triplex ultrasound, ankle-brachial and toe-brachial index tests, occlusive plethysmography comprising two arterial flow phases, and transcutaneous oxygen pressure(TcPO2).

Results

Following bolus administration, the Cmax of AMC was 91.8 ± 52.5 μgmL-1 and the Cmax-tissue of AMC was 7.25 ± 4.5 μgmL-1(P<0.001). The Cmax for CTZ was 186.8 ± 44.1 μgmL-1 and the Cmax-tissue of CTZ was 18.6 ± 7.4 μgmL-1(P<0.0001). Additionally, 67% of patients treated with AMC and 55% of those treated with CTZ achieved tissue fT>MIC levels exceeding 50% and 60%, respectively. We observed positive correlations between both Cmax-tissue and AUCtissue and arterial flow. Specifically, the correlation coefficient for the first phase was r=0.42; (P=0.045), and for the second phase, it was r=0.55(P=0.01)and r=0.5(P=0.021).

Conclusions

Bactericidal activity proved satisfactory in only half to two-thirds of patients with IDFUs, an outcome that appears to correlate primarily with arterial flow.

Diagnosis of infection in the foot of patients with diabetes: A systematic review

BACKGROUND

Securing an early accurate diagnosis of diabetic foot infections and assessment of their severity are of paramount importance since these infections can cause great morbidity and potential mortality and present formidable challenges in surgical and antimicrobial treatment.

METHODS

In June 2022, we searched the literature using PubMed and EMBASE for published studies on the diagnosis of diabetic foot infection (DFI). On the basis of pre-determined criteria, we reviewed prospective controlled, as well as non-controlled, studies in English. We then developed evidence statements based on the included papers.

RESULTS

We selected a total of 64 papers that met our inclusion criteria. The certainty of the majority of the evidence statements was low because of the weak methodology of nearly all of the studies. The available data suggest that diagnosing diabetic foot infections on the basis of clinical signs and symptoms and classified according to the International Working Group of the Diabetic Foot/Infectious Diseases Society of America scheme correlates with the patient's likelihood of the need for hospitalisation, lower extremity amputation, and risk of death. Elevated levels of selected serum inflammatory markers such as erythrocyte sedimentation rate (ESR), C-reactive protein and procalcitonin are supportive, but not diagnostic, of soft tissue infection. Culturing tissue samples of soft tissues or bone, when care is taken to avoid contamination, provides more accurate microbiological information than culturing superficial (swab) samples. Although non-culture techniques, especially next-generation sequencing, are likely to identify more bacteria from tissue samples including bone than standard cultures, no studies have established a significant impact on the management of patients with DFIs. In patients with suspected diabetic foot osteomyelitis, the combination of a positive probe-to-bone test and elevated ESR supports this diagnosis. Plain X-ray remains the first-line imaging examination when there is suspicion of diabetic foot osteomyelitis (DFO), but advanced imaging methods including magnetic resonance imaging (MRI) and nuclear imaging when MRI is not feasible help in cases when either the diagnosis or the localisation of infection is uncertain. Intra-operative or non-per-wound percutaneous biopsy is the best method to accurately identify bone pathogens in case of a suspicion of a DFO. Bedside percutaneous biopsies are effective and safe and are an option to obtain bone culture data when conventional (i.e. surgical or radiological) procedures are not feasible.

CONCLUSIONS

The results of this systematic review of the diagnosis of diabetic foot infections provide some guidance for clinicians, but there is still a need for more prospective controlled studies of high quality.

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.

Comorbid status in patients with osteomyelitis is associated with long-term incidence of extremity amputation

INTRODUCTION

Osteomyelitis is associated with significant morbidity, including amputation. There are limited data on long-term amputation rates following an osteomyelitis diagnosis. We sought to determine the incidence of amputation in patients with osteomyelitis over 2 years.

RESEARCH DESIGN AND METHODS

Observational cohort study of 1186 inpatients with osteomyelitis between 2004 and 2015 and stratified by osteomyelitis location status to evaluate the impact on amputation, mortality rates, readmission data, and inpatient days.

RESULTS

Persons with diabetes had 3.65 times greater probability of lower extremity amputation (p<0.001), readmission (p<0.001), and longer inpatient stay (p<0.001) and had higher 2-year mortality (relative risk (RR) 1.23, p=0.0027), adjusting for risk factors. Male gender (RR 1.57, p<0.001), black race (RR 1.41, p<0.05), former smoking status (RR 1.38, p<0.01), myocardial infarction (RR 1.72, p<0.001), congestive heart failure (RR 1.56, p<0.001), peripheral vascular disease (RR 2.25, p<0.001) and renal disease (RR 1.756, p<0.001) were independently associated with amputation. Male gender (RR 1.39, p<0.01), black race (RR 1.27, p<0.05), diabetes (RR 2.77, p<0.001) and peripheral vascular disease (RR 1.59, p<0.001) had increased risk of lower, not upper, extremity amputation.

CONCLUSIONS

Patients with osteomyelitis have higher rates of amputation and hospitalization. Clinicians must incorporate demographic and comorbid risk factors to protect against amputation.

The infected diabetes-related foot: Comparison of erythrocyte sedementation rate/albumin and C-reactive protein/albumin ratios with erythrocyte sedimentation rate and C-reactive protein to differentiate bone and soft tissue infections

The objective of this study was to evaluate the effectiveness of C-reactive protein (CRP)/albumin, erythrocyte sedimentation rate (ESR)/albumin ratio, ESR, CRP and albumin to differentiate bone and soft tissue infection in persons with diabetes. We retrospectively evaluated 242 individuals admitted to hospital with diabetes-related foot infections (DFI). We categorised DFI cases as either bone (OM) or soft tissue infection based on bone culture and/or histology. We evaluated the diagnostic accuracy of CRP, ESR, albumin, CRP/albumin and ESR/albumin as biomarkers to diagnose OM in persons with diabetes. The median age was 53 years (74% male). There were 224 diabetes-related patients of which 125 had been diagnosed with osteomyelitis. The ESR/albumin and CRP/albumin ratios cut-points were >17.84 and >1.83, respectively. ESR/albumin and CRP/albumin ratios had similar diagnostic parameters: AUC (0.71, 0.71), sensitivity (70.0%, 57.0%), specificity (62.0%, 75.0%), positive predictive value (67.0%, 71.0%) and negative predictive value (66.0% and 71.0%). In contrast diagnostic efficiency of CRP and ESR were AUC 0.71 and 0.71, sensitivity (45.6%, 71.2%), specificity (85.5%, 60.7%), positive predictive value (70.0%, 65.9%) and negative predictive value (59.5%, 66.4%), respectively. When comparing area under the curves, the results showed that ESR/albumin was not significantly different to ESR alone (Delong test pvs ESR  >0.1). Similarly, CRP/albumin was not significantly different to CRP alone (Delong test pvs CRP  >0.1). In conclusion, ESR/albumin and CRP/albumin ratios provided comparable results as using ESR and CRP alone.

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.

State-of-the-art update for diagnosing diabetic foot osteomyelitis: a narrative review

Recently, the International Working Group on the Diabetic Foot and the Infectious Diseases Society of America divided diabetic foot disease into diabetic foot infection (DFI) and diabetic foot osteomyelitis (DFO). DFI is usually diagnosed clinically, while numerous methods exist to diagnose DFO. In this narrative review, the authors aim to summarize the updated data on the diagnosis of DFO. An extensive literature search using "diabetic foot [MeSH]" and "osteomyelitis [MeSH]" or "diagnosis" was performed using PubMed and Google Scholar in July 2023. The possibility of DFO is based on inflammatory clinical signs, including the probe-to-bone (PTB) test. Elevated inflammatory biochemical markers, especially erythrocyte sedimentation rate, are beneficial. Distinguishing abnormal findings of plain radiographs is also a first-line approach. Moreover, sophisticated modalities, including magnetic resonance imaging and nuclear medicine imaging, are helpful if doubt remains after a first-line diagnosis. Transcutaneous bone biopsy, which does not pass through the wound, is necessary to avoid contaminating the sample. This review focuses on the current diagnostic techniques for DFOs with an emphasis on the updates. To obtain the correct therapeutic results, selecting a proper option is necessary. Based on these numerous diagnosis modalities and indications, the proper choice of diagnostic tool can have favorable treatment outcomes.

Is the duration of diabetic foot ulcers an independent risk factor for developing diabetic foot osteomyelitis?

OBJECTIVE

This study aimed to determine whether the prolonged duration of diabetic foot ulcers was associated with an increased incidence of diabetic foot osteomyelitis.

STUDY DESIGN

A retrospective cohort study METHODS: The medical records of all patients who participated in the diabetic foot clinic between January 2015 and December 2020 were reviewed. Patients with new diabetic foot ulcers were monitored for diabetic foot osteomyelitis. The collected data included the patient's profile, comorbidities and complications, the ulcer profile (area, depth, location, duration, number of ulcers, inflammation, and history of the previous ulcer), and outcome. Univariate and multivariate Poisson regression analyses were used to assess risk variables for diabetic foot osteomyelitis.

RESULTS

Eight hundred and fifty-five patients were enrolled; 78 developed diabetic foot ulcers (cumulative incidence 9% over 6 years, average annual incidence 1.5%) and among these diabetic foot ulcers, 24 developed diabetic foot osteomyelitis (cumulative incidence 30% over 6 years, average annual incidence of 5%, incidence rate 0.1/person-year). Statistically significant risk factors for the development of diabetic foot osteomyelitis were ulcers that were deep to the bone (adjusted risk ratio 2.50, p = 0.04) and inflamed wounds (adjusted risk ratio 6.20, p = 0.02). The duration of diabetic foot ulcers was not associated with diabetic foot osteomyelitis (adjusted risk ratio 1.00, p = 0.98).

CONCLUSION

The duration was not an associated risk factor for diabetic foot osteomyelitis, while bone-deep ulcers and inflamed ulcers were found to be significant risk factors for the development of diabetic foot osteomyelitis.

Is the Combination of Plain X-ray and Probe-to-Bone Test Useful for Diagnosing Diabetic Foot Osteomyelitis? A Systematic Review and Meta-Analysis

A systematic review and meta-analysis was conducted to assess the diagnostic accuracy of the combination of plain X-ray and probe-to-bone (PTB) test for diagnosing diabetic foot osteomyelitis (DFO). This systematic review has been registered in PROSPERO (a prospective international register of systematic reviews; identification code CRD42023436757). A literature search was conducted for each test separately along with a third search for their combination. A total of 18 articles were found and divided into three groups for separate analysis and comparison. All selected studies were evaluated using STROBE guidelines to assess the quality of reporting for observational studies. Meta-DiSc software was used to analyze the collected data. Concerning the diagnostic accuracy variables for each case, the pooled sensitivity (SEN) was higher for the combination of PTB and plain X-ray [0.94 (PTB + X-ray) vs. 0.91 (PTB) vs. 0.76 (X-ray)], as was the diagnostic odds ratio (DOR) (82.212 (PTB + X-ray) vs. 57.444 (PTB) vs. 4.897 (X-ray)). The specificity (SPE) and positive likelihood ratio (LR+) were equally satisfactory for the diagnostic combination but somewhat lower than for PTB alone (SPE: 0.83 (PTB + X-ray) vs. 0.86 (PTB) vs. 0.76 (X-ray); LR+: 5.684 (PTB + X-ray) vs. 6.344 (PTB) vs. 1.969 (X-ray)). The combination of PTB and plain X-ray showed high diagnostic accuracy comparable to that of MRI and histopathology diagnosis (the gold standard), so it could be considered useful for the diagnosis of DFO. In addition, this diagnostic combination is accessible and inexpensive but requires training and experience to correctly interpret the results. Therefore, recommendations for this technique should be included in the context of specialized units with a high prevalence of DFO.

Detection, management, and prevention of diabetes-related foot disease in the Australian context

Diabetes-related foot disease (DFD) is a widely feared complication among people who live with diabetes. In Australia and globally, rates of disability, cardio-vascular disease, lower extremity amputation, and mortality are significantly increased in patients with DFD. In order to understand and prevent these outcomes, we analyse the common pathogenetic processes of neuropathy, arterial disease, and infection. The review then summarises important management considerations through the interdisciplinary lens. Using Australian and international guidelines, we offer a stepwise, evidence-based practical approach to the care of patients with DFD.

Addressing the Inertia: A Holistic Approach to Diabetic Foot Evaluation

Diabetic foot is a well-known complication with considerable morbidity and mortality related to the diabetic population. Neuropathy, deformity, infection and ischemia are important contributors to the pathogenesis of diabetic foot ulcers. A multidisciplinary team approach by physicians, nursing staff, diabetic educators and the caregiver as well as close monitoring of feet by the patient himself can prevent foot-related complications. Proper foot care, foot hygiene, annual foot examination and the correct choice of footwear are the main elements in preventing foot problems like deformity, ulceration and amputations. Physicians play a key role in the early detection and prevention of foot problems. Foot evaluation is the most neglected part of physical examination in diabetic patients. This inertia is evident in both physicians and patients. Emphasis on visual inspection and physical foot examination at every visit may address the morbidity and mortality due to diabetic neuropathy and vasculopathy. This article will highlight extensively history taking and foot examination in the diabetic foot clinic. Optimal glycemic control, simple foot care practices, knowledge and appropriate footwear use play an important role to reduce the disease burden.

Is fluoroscopy-guided percutaneous bone biopsy of diabetic foot with suspected osteomyelitis worthwhile? A retrospective study

BACKGROUND

Diabetic foot infection, particularly osteomyelitis, is a major risk factor of amputation in persons with diabetes. Bone biopsy with microbial examination is considered the gold standard of diagnosis of osteomyelitis, providing information about the offending pathogens as well as their antibiotics susceptibility. This allows targeting of these pathogens with narrow spectrum antibiotics, potentially reducing emergence of antimicrobial resistance. Percutaneous fluoroscopy guided bone biopsy allows accurate and safe targeting of the affected bone.

METHODS

In a single tertiary medical institution and over 9 year period, we performed 170 percutaneous bone biopsies. We retrosepctively reviewed the medical record of these patients including patients' demographics, imaging and biopsy microbiology and pathollogic results.

RESULTS

Microbiological cultures of 80 samples (47.1%) were positive with 53.8% of the positive culture showed monomicrobial growth and the remaining were polymicrobial. Of the positive bone samples 71.3% grew Gram-positive bacteria. Staphylococcus aureus was the most frequently isolated pathogen from positive bone cultures with almost one third showing methicillin resistence. Enterococcus species were the most frequently isolated pathogens from polymicrobial samples. Enterobacteriaceae species were the most common Gram-negative pathogens and were more common in polymicrobial samples.

CONCLUSIONS

Percutaneous image-guided bone biopsy is a low-risk, minimally invasive procedure that can provide valuable information about microbial pathogens and therefore enable targeting these pathogens with narrow spectrum antibiotics.

Hybrid imaging of Diabetic Foot Infections

Diabetic foot infections, a common but diagnostically challenging clinical presentation, requires the difficult differentiation between soft tissue-only infection, diabetic neuropathic osteoarthropathy, osteomyelitis or a combination of these pathological processes. While there are clinical predictors for osteomyelitis and simple bedside tests available, imaging is often required for accurate diagnosis. A variety of anatomic and molecular imaging tests are in clinical use, each with its advantages and disadvantages. This review will provide an overview of the different available imaging modalities and their diagnostic criteria, emphasizing the role of hybrid imaging for the accurate diagnosis of osteomyelitis.

Diabetic foot infection - diagnosis and treatment

Diabetic foot (DF) is one of the most serious complications of diabetes, leading to high morbidity and mortality in patients with diabetes, significantly affecting their quality of life and placing a huge burden on the healthcare system. Diabetic foot infection (DFI) is a major factor in the non-healing of diabetic ulcerations of the lower limbs, increases the number of hospital admissions, prolongs their duration and is a frequent cause of increased number of amputations. The most serious form of foot infection is osteomyelitis. Management of infection in SDN includes proper diagnosis, including obtaining appropriate specimens for culture, indication of rational antimicrobial therapy or early surgical intervention, and provision of all other necessary wound care and overall patient care to prevent recurrence of DFI.

Diabetic Foot Care: A Screening on Primary Care Providers' Attitude and Practice in Riyadh, Saudi Arabia

Background and Objectives: Diabetic foot (DF) disease is one of the myriad complications of diabetes. Positive outcomes are expected through a multidisciplinary approach as provided by primary care providers (PCPs). This study aimed to assess the knowledge of DF and attitude of physicians in primary healthcare settings toward DF diagnosis and prevention in Saudi Arabia. Materials and Methods: This observational cross-sectional study used a self-administered questionnaire that was completed by family medicine consultants, residents, and general practitioners working in primary care settings in Riyadh. Results: Of the 152 physicians who completed the survey, (43.4%) completed more than 10 h of diabetes continuing medical education (CME) over the past three years. Most (96.1%) PCPs educate patients about foot self-inspection, and only (64.5%) perform foot inspection at every visit in high-risk diabetic foot patients. PCP knowledge about diagnosing and managing diabetic foot infection was suboptimal. Only 53.9% of participants reported performing a probe-to-bone in DF patients with open wounds. Conclusions: We identified knowledge and action gaps among PCPs. Physicians had acceptable knowledge about preventive measures. However, deficits were found regarding diagnosing and management of DF infections. We recommend addressing these knowledge gaps by incorporating DF lectures and workshops within family medicine conferences and residency programs.

Limb Salvage in Severe Diabetic Foot Infection

Severe diabetic foot infections (DFI) are both limb threatening and life threatening and associated with negative impact on health-related quality of life. Most severe DFIs require surgical intervention, and the goal of treatment should be preservation of limb function in addition to eradication of infection. Minor amputations are required in approximately 40% and major amputations in approximately 20% of patients. Significant risk factors for lower extremity amputation included male gender, smoking, previous amputation, osteomyelitis, peripheral artery disease, retinopathy, severe infections, gangrene, neuroischemic diabetic foot infections, leukocytosis, positive wound cultures, and isolation of gram-negative bacteria.

The Role of Serial Radiographs in Diagnosing Diabetic Foot Bone Osteomyelitis

Background and Objective

Diagnosing diabetes-related foot osteomyelitis is sometimes a challenge for clinicians since it may occur without local or systemic signs of infection. Thus, the primary purpose of this article was to evaluate the role of progressive radiographic changes in diagnosing diabetic foot osteomyelitis.

Materials and Methods

A retrospective review of databases of our Institution was performed to identify all long-standing diabetic foot patients who underwent two radiographic examinations spaced no more than five weeks apart and a subsequent magnetic resonance (MR) examination from November 2015 to November 2020. A total of 46 patients (32 men, 14 women; mean age, 57.3 years) were identified.

Results

serial radiographs showed 89% sensitivity, 38% specificity, 80% diagnostic accuracy, 87% positive predictive value (PPV), 43% negative predictive value (NPV) to diagnose osteomyelitis (P value < 0,05). Bone destruction was the most reliable radiographic sign with 89% sensitivity, 88% specificity, 89% diagnostic accuracy, 97% PPV, 64% NPV (P value < 0,05).

Conclusion

Progressive bony changes detected by serial radiographs are a useful tool to diagnose diabetic foot osteomyelitis.

Experience in the use of dalbavancin in diabetic foot infection

OBJECTIVE

To describe the clinical experience with dalbavancin in the treatment of diabetic foot infection in a multidisciplinary unit of a second level hospital.

METHODS

A retrospective, descriptive study was made with all patients with diabetic foot infection treated with dalbavancin in the Diabetic Foot Unit of Hospital Universitario Fundación Alcorcón, covering the period from September 2016 to December 2019. Demographic parameters and comorbidities, characteristics of the infection and treatment with dalbavancin were recorded. The cure rate is estimated at 90 days after finishing the treatment.

RESULTS

A total of 23 patients with diabetic foot infection (osteomyelitis) started treatment with dalbavancin, 19 were men and the mean age was 65 years. The microorganisms most frequently isolated for the indication of treatment with dalbavancin were Staphylococcus aureus (11) and Corynebacterium striatum (7). Dalbavancin was used as a second choice therapy in 22 cases, in 11 due to toxicity from other antibiotics. The median duration of treatment was 5 (4-7) weeks; the most frequent dose of dalbavancin (8 patients) was 1000 mg followed by 500 mg weekly for 5 weeks. 3 patients presented mild side effects (nausea and gastrointestinal discomfort). At 90 days after completion of dalbavancin therapy, 87% (20) of the patients were cured (95% CI: 65.2%-94.52%).

CONCLUSION

Patients with osteomyelitis due to gram-positive microorganisms who received as part of the multidisciplinary antibiotic treatment with dalbavancin, had a high rate of cure with adequate tolerance and few side effects. Dalbavancin offers a safe alternative in treating deep diabetic foot infection.

Use of Novel Strategies to Develop Guidelines for Management of Pyogenic Osteomyelitis in Adults: A WikiGuidelines Group Consensus Statement

IMPORTANCE

Traditional approaches to practice guidelines frequently result in dissociation between strength of recommendation and quality of evidence.

OBJECTIVE

To construct a clinical guideline for pyogenic osteomyelitis management, with a new standard of evidence to resolve the gap between strength of recommendation and quality of evidence, through the use of a novel open access approach utilizing social media tools.

EVIDENCE REVIEW

This consensus statement and systematic review study used a novel approach from the WikiGuidelines Group, an open access collaborative research project, to construct clinical guidelines for pyogenic osteomyelitis. In June 2021 and February 2022, authors recruited via social media conducted multiple PubMed literature searches, including all years and languages, regarding osteomyelitis management; criteria for article quality and inclusion were specified in the group's charter. The GRADE system for evaluating evidence was not used based on previously published concerns regarding the potential dissociation between strength of recommendation and quality of evidence. Instead, the charter required that clear recommendations be made only when reproducible, prospective, controlled studies provided hypothesis-confirming evidence. In the absence of such data, clinical reviews were drafted to discuss pros and cons of care choices. Both clear recommendations and clinical reviews were planned with the intention to be regularly updated as new data become available.

FINDINGS

Sixty-three participants with diverse expertise from 8 countries developed the group's charter and its first guideline on pyogenic osteomyelitis. These participants included both nonacademic and academic physicians and pharmacists specializing in general internal medicine or hospital medicine, infectious diseases, orthopedic surgery, pharmacology, and medical microbiology. Of the 7 questions addressed in the guideline, 2 clear recommendations were offered for the use of oral antibiotic therapy and the duration of therapy. In addition, 5 clinical reviews were authored addressing diagnosis, approaches to osteomyelitis underlying a pressure ulcer, timing for the administration of empirical therapy, specific antimicrobial options (including empirical regimens, use of antimicrobials targeting resistant pathogens, the role of bone penetration, and the use of rifampin as adjunctive therapy), and the role of biomarkers and imaging to assess responses to therapy.

CONCLUSIONS AND RELEVANCE

The WikiGuidelines approach offers a novel methodology for clinical guideline development that precludes recommendations based on low-quality data or opinion. The primary limitation is the need for more rigorous clinical investigations, enabling additional clear recommendations for clinical questions currently unresolved by high-quality data.

Effect of Sensory Neuropathy on the Predictive Value of Inflammatory Biomarkers for Osteomyelitis in Diabetic and Nondiabetic Patients with Foot Infections

OBJECTIVE

To investigate the predictive value of erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) in persons with and without diabetes with osteomyelitis (OM).

METHODS

We evaluated 455 patients in a retrospective cohort study of patients admitted to the hospital with diabetic foot OM (n = 177), diabetic foot soft-tissue infections (STIs) (n = 176), nondiabetic OM (n = 51), and nondiabetic STIs (n = 51). Infection diagnosis was determined through bone culture, histopathologic examination for OM, and/or imaging (magnetic resonance imaging/single-photon emission computed tomography) for STI. The optimal cutoff values of ESR and CRP in predicting OM were determined by receiver operating characteristic curve analysis. Sensitivity, specificity, positive and negative predictive values, and positive and negative likelihood ratios were determined through contingency tables.

RESULTS

In persons without diabetes with STI or OM, the mean ESR and CRP differences were 10.0 mm/h and 2.6 mg/dL, respectively. In contrast, persons with diabetes had higher levels of each: 24.8 mm/h and 6.8 mg/dL, respectively. As a result, ESR and CRP predicted OM better in patients with diabetes. However, when patients were stratified by neuropathy status, ESR remained predictive of OM in diabetic patients with neuropathy (75% sensitivity, 58% specificity) but not in diabetic patients without neuropathy (50% sensitivity, 44% specificity). Also, CRP remained predictive irrespective of neuropathy status. A similar trend was observed in patients without diabetes.

CONCLUSIONS

Previous studies have reported that ESR and CRP are predictive of OM. However, this study suggests that neuropathy influences the predictive value of inflammatory biomarkers. The underlying mechanisms require further study.

Opinions about the most appropriate surgical management of diabetes-related foot infection: a cross-sectional survey

Background

There is a lack of high quality evidence to guide the optimal management of diabetes-related foot infection, particularly in cases of severe diabetes-related foot infection and diabetes-related foot osteomyelitis. This study examined the opinions of surgeons about the preferred management of severe diabetes-related foot infection.

Methods

Vascular and orthopaedic surgeons in Australia and New Zealand were invited to complete an online survey via email. The survey included multi-choice and open-ended questions on clinical management of diabetes-related foot infection. Responses of vascular surgeons and orthopaedic surgeons were compared using non-parametric statistical tests. Open-text responses were examined using inductive content analysis.

Results

29 vascular and 20 orthopaedic surgeons completed the survey. One-third (28.6%) used best-practice guidelines to assist in decisions about foot infection management. Areas for guideline improvement identified included more specific advice regarding the indications for available treatments, more recommendations about non-surgical patient management and advice on how management can be varied in regions with limited health service resource. The probe-to-bone test and magnetic resonance imaging were the preferred methods of diagnosing osteomyelitis. Approximately half (51.2%) of respondents indicated piperacillin combined with tazobactam as the preferred antibiotic choice for empirical treatment of severe diabetes-related foot infection. Negative pressure wound therapy was the most common way of managing a wound following debridement. All vascular surgeons (100%) made revascularisation decisions based on the severity of ischemia while most orthopaedic surgeons (66.7%) were likely to refer to vascular surgeons to make revascularisation decisions. Vascular surgeons preferred using wound swabs while orthopaedic surgeons favoured tissue or bone biopsies to determine the choice of antibiotic. Respondents perceived a moderate variation in management decisions between specialists and supported the need for randomised controlled trials to test different management pathways.

Conclusions

Most vascular and orthopaedic surgeons do not use best-practice guidelines to assist in decisions about management of diabetes-related foot infection. Vascular and orthopaedic surgeons appear to have different preferences for wound sampling to determine choice of antibiotic. There is a need for higher quality evidence to clarify best practice for managing diabetes-related foot infection.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13047-022-00523-w.

A Comprehensive Review of the Pathogenesis, Diagnosis, and Management of Diabetic Foot Infections

GENERAL PURPOSE

To review an approach to diabetic foot infections (DFIs), including acute osteomyelitis, while also discussing current practices and the challenges in diagnosis and management.

TARGET AUDIENCE

This continuing education activity is intended for physicians, physician assistants, nurse practitioners, and nurses with an interest in skin and wound care.

LEARNING OBJECTIVES/OUTCOMES

After participating in this educational activity, the participant will1. Identify the risk factors for developing DFIs.2. Outline diagnostic techniques for assessing DFIs.3. Select the assessment techniques that support a diagnosis of osteomyelitis.4. Choose the appropriate pharmacologic and nonpharmacologic treatment options for patients who have DFIs.

ABSTRACT

Diabetic foot ulcers result from a combination of peripheral neuropathy, vascular compromise, and repetitive trauma. Approximately 50% of individuals with diabetic foot ulcers will develop a diabetic foot infection (DFI), and 20% of individuals with a DFI will develop osteomyelitis. Herein, the authors review an approach to DFIs including acute osteomyelitis and discuss current practices and challenges in diagnosis and management.The diagnosis of a skin and soft tissue DFI is based on clinical criteria. A bone biopsy is considered the criterion standard for diagnosis of osteomyelitis; however, biopsy is not always feasible or available. Consequently, diagnosis can be made using a combination of clinical, biochemical, and radiographic findings. X-ray is the recommended imaging modality for initial evaluation; however, because of its lower relative sensitivity, advanced imaging may be used when clinical suspicion remains after negative initial testing.The microbiology of skin and soft tissue DFIs and osteomyelitis is similar. Staphylococcus aureus and other Gram-positive cocci are the most common pathogens identified. Deep cultures are preferred in both DFI and osteomyelitis to identify the etiologic pathogens implicated for targeted antimicrobial therapy. Management also requires a multidisciplinary approach. Surgical debridement in those with deep or severe infections is necessary, and surgical resection of infected bone is curative in cases of osteomyelitis. Finally, appropriate wound care is critical, and management of predisposing factors, such as peripheral neuropathy, peripheral arterial disease, tinea, and edema, aids in recovery and prevention.

Clinical Outcomes of Foot Infections in Patients Without Diabetes

The aim of this study was to report clinical outcomes of moderate and severe foot infections in patients without diabetes. Medical records of 88 nondiabetic patients with foot infections treated at a safety net hospital were retrospectively reviewed. Patients were grouped by the presence of soft-tissue infection (STI) or osteomyelitis (OM). The diagnosis of OM was determined by positive bone culture or histopathology. STIs were defined by negative bone biopsy or negative imaging with magnetic resonance imaging or computed tomography/dual-modality radiolabeled white blood cell single-photon emission computed tomography. Patient outcomes were recorded ≤1 year after admission. Eighty-eight nondiabetic patients admitted to our institution for moderate or severe foot infections were included, 45 OM and 43 STI. No differences were noted in patient characteristics except that OM patients had a higher prevalence of neuropathy (66.7% versus 39.5%, p = .02). OM patients required surgery more often (97.8% versus 67.4%, p < .01), a greater number of surgeries (2.0 ± 1.2 versus 1.4 ± 1.3, p = .02), and more amputations (75.6% versus 11.6%, p < .01) than STI patients. OM patients had a higher proportion of wounds that healed (82.2% versus 62.8%, p = .04). There were no significant differences in reinfection (35.6% versus 25.6%, p = .36), foot-related readmission to hospital (35.6% versus 23.3%, p = .25), or total duration of antibiotics (13.9 ± 10.2 versus 13.5 ± 12.9, p = .87) between OM and STI patients. In conclusion, OM patients required more surgeries and amputations than patients with STIs; however, they had similar rates of reinfection and readmission within a year after the index hospitalization.

[Multidisciplinary management of diabetic foot ulcer infection]

Infection is one of the most common complications of diabetic foot ulceration resulting in lower extremity amputations and early mortality in this population. Several factors influence the course of diabetic foot ulceration infection and in that context, integrated multidisciplinary management is required as soon as possible. In fact, a holistic interdisciplinary approach should be the standard of care. Whether the infection is categorized as mild, moderate or severe, with or without bone infection, the overall individual's characteristics must be addressed, in addition to local wound care, offloading and antibiotic therapy. Some severe infections have potential indications for hospitalization and are considered as surgical emergencies. In some DFU cases, surgical revascularization of the limb is mandatory to treat the infection. However, surgical interventions and amputations, are sometimes inevitable, they are predictors of bad prognosis. Although some adjuvant therapies are effective to promote wound healing, their use is not recommended to treat diabetic foot ulcer infection. Infection management can be divided into three general interventions: proper clinical diagnosis, microbiological and imaging investigations, and treatment. This review is an update on the up-to-date evidences in scientific literature and includes the latest recommendations from the International Working Group on the Diabetic Foot (IWGDF).

Experience in the use of dalbavancin in diabetic foot infection

OBJECTIVE

To describe the clinical experience with dalbavancin in the treatment of diabetic foot infection in a multidisciplinary unit of a second level hospital.

METHODS

A retrospective, descriptive study was made with all patients with diabetic foot infection treated with dalbavancin in the Diabetic Foot Unit of Hospital Universitario Fundación Alcorcón, covering the period from September 2016 to December 2019. Demographic parameters and comorbidities, characteristics of the infection and treatment with dalbavancin were recorded. The cure rate was estimated at 90 days after finishing the treatment.

RESULTS

A total of 23 patients with diabetic foot infection (osteomyelitis) started treatment with dalbavancin, 19 were men and the mean age was 65 years. The microorganisms most frequently isolated for the indication of treatment with dalbavancin were Staphylococcus aureus (11) and Corynebacterium striatum (7). Dalbavancin was used as a second choice therapy in 22 cases, in 11 due to toxicity from other antibiotics. The median duration of treatment was 5 (4-7) weeks; the most frequent dose of dalbavancin (8 patients) was 1000mg followed by 500mg weekly for 5 weeks. 3 patients presented mild side effects (nausea and gastrointestinal discomfort). At 90 days after completion of dalbavancin therapy, 87% (20) of the patients were cured (95% CI: 65.2%-94.52%).

CONCLUSION

Patients with osteomyelitis due to gram-positive microorganisms who received as part of the multidisciplinary antibiotic treatment with dalbavancin, had a high rate of cure with adequate tolerance and few side effects. Dalbavancin offers a safe alternative in treating deep diabetic foot infection.

Genetic Polymorphisms and the Risk of Diabetic Foot: A Systematic Review and Meta-Analyses

BACKGROUND

Diabetic foot (DF) is a dangerous complication of diabetes. The aim of the study was to synthesize all the published single nucleotide polymorphisms (SNPs) of DF to objectively evaluate the relationship of SNPs and DF risks.

METHODS

The HuGE database and CNKI were searched for eligible publications on genetic polymorphisms and the risk of DF systematically. The quality of literatures was evaluated by the Newcastle-Ottawa scale. Pooled odds ratios with a 95% confidence interval for SNPs were evaluated through 3 genetic models.

RESULTS

Citing 29 different polymorphisms from 24 articles and the study met our selection criteria. There were 24 polymorphisms summarized systematically, and 5 merged polymorphisms for a meta-analysis: 9 positively associated with DF: HIF-1α rs11549465, TNF-α rs1800629, TLR-9 rs5743836, FIB rs6056, HSP70-2437C/T, VDR rs2228570, LOX rs1800449, ITLN1 rs2274907, and OPG rs2073617, but OPG rs3134069 was not a risk factor in DF; 6 negatively associated with DF: VEGF rs833061 and rs2010963, MCP-1 rs1024611, SDF-1 rs1801157, SIRT1 rs12778366, and OPG rs2073617. In addition, 13 polymorphisms were not associated with DF: MMP-9 rs3918242, eNOS rs1799983, VEGF rs3025039, -7C/T, rs1570360, rs13207351, and rs699947, IL-6 rs1800795, HIF-1α rs11549467, TNF-α rs361525, TLR-2 rs3804100, SIRT1 rs3758391, and TIMP-1 rs2070584.

CONCLUSIONS

The study provided some evidence for SNPs to the development of diabetic foot. The meta-analysis showed that rs1024611 of MCP-1 may be regarded as a protective factor, especially in Asian populations. Other loci indicated inconsistent results.

Ultrasound in the Modern Management of the Diabetic Foot Syndrome: A Multipurpose Versatile Toolkit

Ultrasound (US) is a noninvasive and versatile technology that in recent years found acceptance in almost all the medical specialties, with diagnostic and interventional applications. In the diabetic foot syndrome (DFS), US found specific indications mainly in the screening, quantification, and follow-up of the vascular component of the pathology, but also in the study of the deformities and structural modifications induced by neuropathy and in the diagnosis and surgical management of infections, especially those that induce anatomical changes, like abscesses and fasciitis. This review will summarize all these application of US, giving special attention to the vascular aspects, and on the predominant role that US gained in recent times to guide the indication to revascularization, on the new standardized approach to the study of the arterial tree of the limb and the foot, the so-called duplex ultrasound arterial mapping, which significantly increased the utilization of US to plan the revascularizations in this complex pathology. Outside the vascular fields, the diagnosis of neuropathy and infection and the intraoperative use of US in the surgical management of abscesses and fasciitis will be discussed, leaving the last part to the new and interesting applications of US in the management of DFU, a field that is still in evolution, offering new possibilities to the health care professionals involved in the management of these chronic wounds. The variety of applications both in diagnostic and operative fields makes US a rather versatile technology-a toolkit-that should have a special place among those at reach of the specialists of DFS care.

Diabetic Foot. Part 1: Ulcers and Infections

Diabetes is a systemic disease that has achieved epidemic proportions in modern society. Ulcers and infections are common complications in the feet of patients with advanced stages of the disease, and are the main cause of amputation of the lower limb. Peripheral neuropathy is the primary cause of loss of the protective sensation of the feet and frequently leads to plantar pressure ulcers and osteoarticular disruption, which in turn develops into Charcot neuropathy (CN). Common co-factors that add to the morbidity of the disease and the risk of amputation in this population are obesity, peripheral arterial disease, immune and metabolic disorders. Orthopedic surgeons must be aware that the early detection and prevention of these comorbidities, through diligent medical care and patient education, can avoid these amputations.

Financial Impact of Magnetic Resonance Imaging in the Surgical Treatment of Foot and Ankle Osteomyelitis

Magnetic resonance imaging (MRI) is generally considered the most sensitive imaging for diagnosis of osteomyelitis; however, it is associated with significant cost and is at times ordered as initial screening imaging when a less resource-intensive test would suffice. The purpose of this retrospective cohort study was to examine the differences between patients with osteomyelitis of the foot and ankle, and their subsequent treatment course, who underwent MRI compared with those who did not. Financial impact of MRI as it relates to clinical decision-making was also calculated. Patients treated for a diagnosis of osteomyelitis of the foot and ankle from 2009 to 2015 were retrospectively identified. Demographics, imaging modalities, and operative procedures for each patient were collected. An "impact MRI" was defined as one that led to a subsequent operative procedure within the same admission. The impact cost of an MRI was estimated using the equation: (average MRI cost) × (total MRIs/impact MRIs). A total of 144 patients underwent 220 MRIs, and 399 patients did not have MRIs. The operative rate between the 2 groups was similar (70.8% versus 70.4%, p = .93). Multiple linear regression showed that MRI was not a significant predictor of operation (p = .50). However, we found a significant correlation between MRI use and operative intervention for patients with increased comorbidities. From 2011 to 2015, there was a significant increase in impact cost, while controlling for average MRI cost ($8172 to $15,292, p ≤ .05). Over the study period, the impact cost of an MRI significantly increased from 1.8 to 5.0 times the average cost.

Erythrocyte Sedimentation Rate Combined With the Probe-to-Bone Test for Fast and Early Diagnosis of Diabetic Foot Osteomyelitis

This study aimed to investigate the erythrocyte sedimentation rate (ESR) optimal cutoff point in Chinese patients with diabetic foot osteomyelitis (DFO) and to evaluate the screening value of ESR combined with probe-to-bone (PTB) test for a fast diagnosis of DFO in early stage. A total of 204 diabetic inpatients with foot infection were tested for white blood cell count, neutrophil %, C reactive protein, and ESR at admission within 24 hours. All patients were performed PTB test. Patients with DFO (111) were confirmed by bone biopsy, the other patients (86) had only soft tissue infection. Although white blood cell count, neutrophil %, C-reactive protein, and ESR were different between the 2 groups, only area under curve of ESR was 0.832, with the value as a diagnostic indicator. The best cut point of ESR was >43 mm/h; the sensitivity, specificity, positive predictive value (+PV), and negative predictive value (−PV) were 82.9%, 70.5%, 0.78, and 0.77, respectively. ESR combined with PTB test (serial test), the sensitivity, specificity, +PV, −PV, positive likelihood ratio (+LR), and negative LR (−LR) were 63.56%, 98%, 0.97, 0.67, 31.75, and 0.37, respectively. ESR combined with PTB test (parallel test), the sensitivity, specificity, +PV, −PV, +LR, and −LR were 96%, 65.7%, 0.78, 093, 2.8, and 0.06, respectively, combined with PTB test is simple, favorable for application, and can early fast screening patients with DFO in high-risk patients.

Diabetic Foot Infections: The Diagnostic Challenges

Diabetic foot infections (DFIs) are severe complications of long-standing diabetes, and they represent a diagnostic challenge, since the differentiation between osteomyelitis (OM), soft tissue infection (STI), and Charcot’s osteoarthropathy is very difficult to achieve. Nevertheless, such differential diagnosis is mandatory in order to plan the most appropriate treatment for the patient. The isolation of the pathogen from bone or soft tissues is still the gold standard for diagnosis; however, it would be desirable to have a non-invasive test that is able to detect, localize, and evaluate the extent of the infection with high accuracy. A multidisciplinary approach is the key for the correct management of diabetic patients dealing with infective complications, but at the moment, no definite diagnostic flow charts still exist. This review aims at providing an overview on multimodality imaging for the diagnosis of DFI and to address evidence-based answers to the clinicians when they appeal to radiologists or nuclear medicine (NM) physicians for studying their patients.

Heel Pressure Injuries: Consensus-Based Recommendations for Assessment and Management

Significance: A systematic approach to develop experts-based recommendations could have a favorable impact on clinical problems characterized by scarce and low-quality evidence as heel pressure ulcers. Recent Advances: A systematic approach was used to conduce a formal consensus initiative. A multidisciplinary panel of experts identified relevant clinical questions, performed a systematic search of the literature, and created a list of statements. GRADE Working Group guidelines were followed. An independent international jury reviewed and voted recommendations for clinical practice. Consent was developed according to Delphi rules and GRADE method was used to attribute grade of strength. Critical Issues: The extensive search of the literature retrieved 42 pertinent articles (26 clinical studies, 7 systematic reviews or meta-analysis, 5 other reviews, 2 consensus-based articles, and 2 in vitro studies). Thirty-five recommendations and statements were created. Only 1 of 35, concerning ankle-brachial pressure index reliability in diabetic patients, was rejected by the panel. No sufficient agreement was achieved on toe brachial index test to rule out the orphan heel syndrome, removing dry eschar in adult patients without vascular impairment, and using an antimicrobial dressing in children with infected heel pressure injuries. Eleven recommendations were approved with a weak grade of strength. Experts strongly endorsed 20 recommendations. Offloading, stages I and II pressure injuries, and referral criteria were areas characterized by higher level of agreement. Future Directions: We believe that the results of our effort could improve practice, especially in areas where clear and shared opinions emerged. Barriers and limits that could hinder implementation are also discussed in the article.

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

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

Diagnosing diabetic foot osteomyelitis

Bone involvement during an infection of the diabetic foot represents a serious complication associated with a high risk of amputation, prolonged antibiotic treatment and hospitalization. Diabetic foot osteomyelitis (DFOs) require a multidisciplinary approach given the usual complexity of these situations. DFO should be suspected in most cases especially in the most severe forms of soft tissue diabetic foot infections (DFIs) where the prevalence of bone infection may be up to 60%. Suspicion is based on clinical signs in particular a positive probe-to-bone (PTB) test, elevated inflammatory biomarkers especially erythrocyte sedimentation rate and abnormal imaging assessment using plain X-ray as a first-line choice. The combination of PTB test with plain X-ray has proven effective in the diagnosis of DFO. The confirmation (definite) diagnosis of DFO is based on the results of a bone sample examination obtained by either surgical or percutaneous biopsy. Sophisticated imaging examinations such as Magnetic Resonance Imaging (MRI) and nuclear imaging techniques are useful where doubt persists after first-line imaging assessment. These techniques may also help localize the bone infection site and increase the diagnostic performance of percutaneous bone biopsy. The quality of the microbiological documentation of DFO is likely to improve the adequacy of the antimicrobial therapy especially when medical (ie, no surgical resection of the infected bone tissues) is considered. The use of new (molecular) techniques for the identification of the bone pathogens have not yet proven superiority on classic cultural techniques for the management of such patients.

Diagnosis of infection in the foot in diabetes: a systematic review

BACKGROUND

Securing an early accurate diagnosis of diabetic foot infections and assessment of their severity are of paramount importance since these infections can cause great morbidity and potentially mortality and present formidable challenges in surgical and antimicrobial treatment.

METHODS

In June 2018, we searched the literature using PuEbMed and EMBASE for published studies on the diagnosis of diabetic foot infection. On the basis of predetermined criteria, we reviewed prospective controlled, as well as noncontrolled, studies in any language, seeking translations for those not in English. We then developed evidence statements on the basis of the included papers.

RESULTS

From the 4242 records screened, we selected 35 papers that met our inclusion criteria. The quality of all but one of the evidence statements was low because of the weak methodology of nearly all of the studies. The available data suggest that diagnosing diabetic foot infections on the basis of clinical signs and symptoms and classified according to the International Working Group of the Diabetic Foot scheme correlates with the patient's likelihood of ulcer healing, of lower extremity amputation, and risk of death. Elevated levels of selected serum inflammatory markers are supportive, but not diagnostic, of soft tissue or bone infection. In patients with suspected diabetic foot osteomyelitis, both a positive probe-to-bone test and an elevated erythrocyte sedimentation rate are strongly associated with its presence. Culturing tissue samples of soft tissues or bone, when care is taken to avoid contamination, provides more accurate microbiological information than culturing superficial (swab) samples. Plain X-ray remains the first-line imaging examination when there is suspicion of diabetic foot osteomyelitis, but advanced imaging methods help in cases when either the diagnosis or the localization of infection is uncertain.

CONCLUSION

The results of this first reported systematic review on the diagnosis of diabetic foot infections provide some guidance for clinicians, but there is a need for more prospective controlled studies of high quality.

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.

Management of diabetic foot infections in the light of recent literature and new international guidelines

Introduction: In May 2019 the International Working Group on the Diabetic Foot (IWGDF) launched their quadrennially updated guidelines on the management of diabetic foot infections (DFIs). Concomitantly, the number of new publications regarding DFI increased.Areas covered: The IWGDF committee developed and addressed key questions and produced evidence-based recommendations related to diagnosing and treating DFIs. This narrative review provides an overview of this new guideline and also of other recently published literature in the field of DFIs.Expert opinion: The 2019 IWGDF guidelines provide an authoritative, international, evidence-based approach to diagnosing and treating DFIs. The 27 recommendations are supported by systematic reviews of both diagnosis and interventions. Our review of this guideline, along with other recent publications in the field, allows us to offer state-of-the-art guidance for caring for these difficult infections. As the evidence base for management of DFIs remains suboptimal, we need further research to improve the management of DFIs.

Global Vascular Guidelines on the Management of Chronic Limb-Threatening Ischemia

GUIDELINE SUMMARY

Chronic limb-threatening ischemia (CLTI) is associated with mortality, amputation, and impaired quality of life. These Global Vascular Guidelines (GVG) are focused on definition, evaluation, and management of CLTI with the goals of improving evidence-based care and highlighting critical research needs. The term CLTI is preferred over critical limb ischemia, as the latter implies threshold values of impaired perfusion rather than a continuum. CLTI is a clinical syndrome defined by the presence of peripheral artery disease (PAD) in combination with rest pain, gangrene, or a lower limb ulceration >2 weeks duration. Venous, traumatic, embolic, and nonatherosclerotic etiologies are excluded. All patients with suspected CLTI should be referred urgently to a vascular specialist. Accurately staging the severity of limb threat is fundamental, and the Society for Vascular Surgery Threatened Limb Classification system, based on grading of Wounds, Ischemia, and foot Infection (WIfI) is endorsed. Objective hemodynamic testing, including toe pressures as the preferred measure, is required to assess CLTI. Evidence-based revascularization (EBR) hinges on three independent axes: Patient risk, Limb severity, and ANatomic complexity (PLAN). Average-risk and high-risk patients are defined by estimated procedural and 2-year all-cause mortality. The GVG proposes a new Global Anatomic Staging System (GLASS), which involves defining a preferred target artery path (TAP) and then estimating limb-based patency (LBP), resulting in three stages of complexity for intervention. The optimal revascularization strategy is also influenced by the availability of autogenous vein for open bypass surgery. Recommendations for EBR are based on best available data, pending level 1 evidence from ongoing trials. Vein bypass may be preferred for average-risk patients with advanced limb threat and high complexity disease, while those with less complex anatomy, intermediate severity limb threat, or high patient risk may be favored for endovascular intervention. All patients with CLTI should be afforded best medical therapy including the use of antithrombotic, lipid-lowering, antihypertensive, and glycemic control agents, as well as counseling on smoking cessation, diet, exercise, and preventive foot care. Following EBR, long-term limb surveillance is advised. The effectiveness of nonrevascularization therapies (eg, spinal stimulation, pneumatic compression, prostanoids, and hyperbaric oxygen) has not been established. Regenerative medicine approaches (eg, cell, gene therapies) for CLTI should be restricted to rigorously conducted randomizsed clinical trials. The GVG promotes standardization of study designs and end points for clinical trials in CLTI. The importance of multidisciplinary teams and centers of excellence for amputation prevention is stressed as a key health system initiative.

Global vascular guidelines on the management of chronic limb-threatening ischemia

Chronic limb-threatening ischemia (CLTI) is associated with mortality, amputation, and impaired quality of life. These Global Vascular Guidelines (GVG) are focused on definition, evaluation, and management of CLTI with the goals of improving evidence-based care and highlighting critical research needs. The term CLTI is preferred over critical limb ischemia, as the latter implies threshold values of impaired perfusion rather than a continuum. CLTI is a clinical syndrome defined by the presence of peripheral artery disease (PAD) in combination with rest pain, gangrene, or a lower limb ulceration >2 weeks duration. Venous, traumatic, embolic, and nonatherosclerotic etiologies are excluded. All patients with suspected CLTI should be referred urgently to a vascular specialist. Accurately staging the severity of limb threat is fundamental, and the Society for Vascular Surgery Threatened Limb Classification system, based on grading of Wounds, Ischemia, and foot Infection (WIfI) is endorsed. Objective hemodynamic testing, including toe pressures as the preferred measure, is required to assess CLTI. Evidence-based revascularization (EBR) hinges on three independent axes: Patient risk, Limb severity, and ANatomic complexity (PLAN). Average-risk and high-risk patients are defined by estimated procedural and 2-year all-cause mortality. The GVG proposes a new Global Anatomic Staging System (GLASS), which involves defining a preferred target artery path (TAP) and then estimating limb-based patency (LBP), resulting in three stages of complexity for intervention. The optimal revascularization strategy is also influenced by the availability of autogenous vein for open bypass surgery. Recommendations for EBR are based on best available data, pending level 1 evidence from ongoing trials. Vein bypass may be preferred for average-risk patients with advanced limb threat and high complexity disease, while those with less complex anatomy, intermediate severity limb threat, or high patient risk may be favored for endovascular intervention. All patients with CLTI should be afforded best medical therapy including the use of antithrombotic, lipid-lowering, antihypertensive, and glycemic control agents, as well as counseling on smoking cessation, diet, exercise, and preventive foot care. Following EBR, long-term limb surveillance is advised. The effectiveness of nonrevascularization therapies (eg, spinal stimulation, pneumatic compression, prostanoids, and hyperbaric oxygen) has not been established. Regenerative medicine approaches (eg, cell, gene therapies) for CLTI should be restricted to rigorously conducted randomizsed clinical trials. The GVG promotes standardization of study designs and end points for clinical trials in CLTI. The importance of multidisciplinary teams and centers of excellence for amputation prevention is stressed as a key health system initiative.

The Evaluation and Treatment of Diabetic Foot Ulcers and Diabetic Foot Infections

Diabetic foot ulcers and infections are common complications of diabetic foot disease. Additionally, these complications are a common cause of morbidity and impose a substantial burden to the patient and society. It is imperative to understand the major contributing factors, namely, diabetic neuropathy, peripheral arterial disease, and immune system dysfunction in order to guide treatment. Management of diabetic foot disease begins with a detailed history and thorough physical examination. This examination should focus on the manifestations of diabetic neuropathy and peripheral arterial disease, and, in particular, any evidence of diabetic foot ulcers or infection. Prevention strategies should include a multi-disciplinary approach centered on patient education.