The Role of Serum Procalcitonin, Interleukin-6, and Fibrinogen Levels in Differential Diagnosis of Diabetic Foot Ulcer Infection

Establishing a clinical prediction model for diabetic foot ulcers in type 2 diabetic patients with lower extremity arteriosclerotic occlusion using machine learning

The burden of diabetic foot ulcers (DFU) is exacerbated in diabetic patients with concomitant arteriosclerotic occlusion disease (ASO) in the lower extremities, who experience more severe symptoms and poorer prognoses. The study aims to develop a predictive model grounded in machine learning (ML) algorithms, specifically tailored to forecast the occurrence of DFU in diabetic patients with lower extremity ASO. The study involves the data from diabetic patients diagnosed with lower extremity ASO from January 1, 2011 to August 31, 2023. We conducted quality control on the data. Subsequently, the dataset was divided into a training set comprising patients before 2020 and a validation set comprising patients in 2020 and onwards. Patients were stratified into the DFU group or the non-DFU group based on the occurrence of DFU. Intergroup comparisons were conducted to analyze the differences between these two groups. Logistic regression analyses, 3 kinds of machine learning algorithms, a predictive model and nomogram was formulated to estimate the risk of DFU occurrence among diabetic patients with lower extremity ASO. Internal validation of the model was undertaken using the bootstrap method, combing with external temporal validation, with the results visually presented through the Receiver Operating Characteristic (ROC) curve and the Calibration curve. To evaluate the clinical practicality of the model, Decision Curve Analysis (DCA) and Clinical Impact Curve (CIC) were employed. Body Mass Index (BMI), hypertension, coronary heart disease, diabetic nephropathy, the number of lower leg artery occlusions, controlling glucose by insulin injection, age, number of cigarettes smoked per day, diastolic blood pressure, and C-reactive protein (CRP) were utilized to construct a clinical prediction model. This model exhibited a high predictive performance (AUC = 0.962), and the results from both internal validation and external temporal validation further confirmed its high accuracy and reproducibility (AUC = 0.968 and AUC = 0.977, respectively). Additionally, DCA and CIC demonstrated the high clinical practicality of this model. The clinical prediction model exhibited excellent accuracy and reproducibility, along with broad clinical practicality. It provides a good reference for the diagnosis and treatment of DFU.

Comparison of Procalcitonin Levels in Diabetic Foot Ulcer Infection and Osteomyelitis: A Systematic Review and Meta-Analysis

BackgroundFoot ulcers represent a major complication in patients with diabetes and are often challenging for clinicians. Distinguishing between infected and non-infected diabetes foot ulcers (DFUs) can prevent many irreversible injuries such as inappropriate antibiotic therapy, amputation, and even death. Procalcitonin (PCT) has been proposed in the diagnosis of infection and osteomyelitis in diabetes foot ulcers. The present study aimed to compare PCT levels between patients with and without infected diabetes foot ulcer (IDFU).MethodThis review searched three databases including PubMed, Web of Science, and Scopus to identify all articles reporting PCT levels in two groups of infected diabetes foot ulcer (IDFU) and non-infected diabetes foot ulcer (NIDFU). Quality has been assessed using the NIH tool. The pooled mean difference (MD) of PCT level between groups was estimated by random effect meta-analysis. In addition, The PRISMA 2020 statement has been used to update guidelines for reporting present systematic reviews.ResultTwenty-three studies were eligible for meta-analysis, of which data from 2412 people was extracted. Pooled estimation of PCT level was significantly higher in IDFU patients compared with NIDFU patients (MD = 0.25 ng/l, 95% CI: 0.14-0.37). According to the meta-analysis results, PCT level was not significantly higher in patients with Osteomyelitis compared with those without Osteomyelitis (MD = 0.59 ng/l, 95% CI: -0.19, 1.38, I2 = 98.5%).ConclusionSince the results of the present study showed higher PCT levels in patients with IDFU compared to those without, it can be suggested that procalcitonin might be applied as an additional biomarker for the differentiation of NIDFU from IDFU. It needs more evidence to conclude about the role of PCT in terms of osteomyelitis and amputation.

Analysis of risk factors for foot ulcers in diabetes patients with neurovascular complications

BACKGROUND

Diabetic foot ulcers (DFU), characterized by open sores or wounds primarily occurring on the feet of diabetes patients, are a serious and highly morbid complication of long-standing diabetes, accounting for significant morbidity and mortality. These ulcers develop when diabetes damages both nerves and blood vessels, a combination known as neurovascular complications. Neurovascular disease is a well-established risk factor. While studies have extensively examined risk factors for DFU, few have specifically focused on patients with diabetic neurovascular disease. Therefore, we assess the prevalence and risk factors for DFU in diabetic patients with established neurovascular complications.

METHODS

This study analyzed data from 6722 patients with diabetic neurovascular disease aged over 18 years old from the Southern Medical University Nanfang Hospital (SMUNFH) database (2018-2023) and 2689 patients with the same condition and age range from the National Institutes of Health (NIH) Integrated Surveillance System (NIS) database (2017-2019). The incidence of DFU was determined using information from the NIS database and SMUNFH databases. A binary logistic regression model was employed to explore the risk factors for DFU.

RESULTS

The incidence of DFU among neurovascular disease patients was 13.4% at SMUNH and 25.9% in the NIS Asian population. Multiple regression analysis identified several factors associated with DFU in the SMUNH database, including diabetic retinopathy, diabetic nephropathy, osteomyelitis, coronary heart disease, tinea pedis (fungal foot infection), sepsis, ability to sense a 128 Hz tuning fork (both left and right sides), C-reactive protein (CRP) levels, and urinary albumin-to-creatinine ratio (ACR). Analysis of NIS data revealed that in the broader Asian population, peripheral vascular disorders and osteomyelitis were associated with DFU.

CONCLUSION

The prevalence of DFU is higher in Asia than in China. Focusing on peripheral vascular disorders and osteomyelitis can effectively reduce the prevalence of DFU in the Asian population while addressing diabetic retinopathy, diabetic nephropathy, osteomyelitis, coronary heart disease, tinea pedis, ability to sense a 128 Hz tuning fork, CRP levels, and urinary ACR can be effective in China.

Association Between Systemic Immune-Inflammatory Index (SIRI) and Diabetic Foot Ulcers in Individuals with Diabetes: Evidence from the NHANES

Background: Diabetic Foot Ulcer (DFU) is a common and challenging complication of diabetes mellitus, associated with high recurrence, hospitalization, disability, and mortality rates. The Systemic Immune Inflammatory Index (SIRI) based on complete blood counts has been shown to correlate with several diseases but has not been widely studied in DFU.This study aimed to explore the relationship between SIRI and the presence of DFU in individuals with diabetes using data from the National Health and Nutrition Examination Survey (NHANES). Methods: A cross-sectional analysis was conducted on 1246 individuals with diabetes from NHANES cycles 1999-2000, 2001-2002, and 2003-2004. DFUs were identified through patient self-reported data. Multivariate logistic regression models assessed the association between SIRI and DFU, adjusting for potential confounders. Subgroup and interaction analyses were also performed. Results: A total of 117 patients were identified as having DFU. Elevated SIRI levels were significantly associated with DFU presence. In fully adjusted models, a 1-unit increase in SIRI was associated with 24.0% higher odds of DFU prevalence (OR = 1.24; 95% CI: 1.07, 1.43) Subgroup analyses revealed consistent associations across different groups of age, gender, body mass index (BMI), HbA1c, blood glucose, and hemoglobin levels. Conclusion: The findings indicate a positive correlation between SIRI and DFUpresence. Further research is warranted to elucidate the mechanistic links and explore the clinical utility of SIRI in DFU management.

Systematic review and meta-analysis of the diagnostic accuracy of inflammatory markers for infected diabetic foot ulcer

BACKGROUND

The aim was to evaluate the diagnostic value of ESR, CPR, PCT, and WBC in patients with infected diabetic foot ulcer (DFU).

METHODS

The MEDLINE, Embase, BIOSIS, Cochrane databases, and Web of Knowledge databases were searched, without language restriction, to July 2023. Original studies were selected that reported the performance of ESR, CPR, PCT, and WBC in diagnosing infected DFU. To assess the diagnostic value of biomarkers for infected DFU, pooled sensitivity, specificity, positive likelihood ratio (PLR), negative likelihood ratio (NLR), diagnostic odds ratio (DOR), and area under the summary receiver operating characteristic curve (ROC-AUC) were calculated.

RESULTS

Ten studies with 765 patients were identified in our meta-analysis. The pooled sensitivity and specificity of ESR was 0.82 (95 % CI: 0.68-0.91) and 0.83 (95 % CI: 0.69-0.91) respectively. The pooled sensitivity and specificity of CRP was 0.81 (95 % CI: 0.65-0.91) and 0.91 (95 % CI: 0.79-0.96) respectively. The pooled sensitivity and specificity of PCT was 0.76 (95 % CI: 0.65-0.85) and 0.89 (95 % CI: 0.78-0.95) respectively. The pooled sensitivity and specificity of WBC was 0.75 (95 % CI: 0.64-0.83) and 0.79 (95 % CI: 0.67-0.88) respectively. CRP showed the best diagnostic accuracy at distinguishing infected DFU from noninfected DFU with an AUC of 0.93, followed by PCT (AUC of 0.89), ESR (AUC of 0.89), and WBC (AUC of 0.84).

CONCLUSION

CPR levels had high efficiency in distinguishing infected DFU from noninfected DFU, followed by PCT, ESR and WBC. All of these biomarkers could be helpful for early diagnosis of infected DFU. New biomarkers for improving medical decision in diagnosis of infected DFU are highly desirable.

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.

The potential impact and diagnostic value of inflammatory markers on diabetic foot progression in type II diabetes mellitus: A case-control study

BACKGROUND

The wound-healing process in diabetic foot is affected by pro and anti-inflammatory markers, and any disruption in the inflammatory reaction interferes with tissue homeostasis, leading to chronic non-wound healing.

AIM

This study aimed to determine the diagnostic value and effect of CRP, IL-6, TNF, and HbA1c on initiation the and progression of diabetic foot ulcers.

METHOD

ELISA was used to quantify IL-6, TNF, CRP, and HbA1c in 205 patients with diabetes, and 105 were diabetic foot free. The prevalence and progression of diabetic foot were also evaluated. The area under the curve (AUC) was calculated using the receiver operating characteristic (ROC) curve to analyze the predictive values. Forward stepwise logistic regression analysis was used to compute the odds ratio (OR) and the corresponding 95% confidence intervals (CIs).

RESULTS

CRP, IL-6, and FBS were found to be significant predictors of diabetic foot (OR=1.717, 95% CI=1.250-2.358, P=0.001; OR=1.434, 95% CI=1.142-1.802, P=0.002; and OR=1.040, 95% CI=1.002-1.080, P=0.037), respectively. The AUCs for CRP, IL-6, and HbA1c in predicting diabetic foot were 0.839, 0.728, and 0.834, respectively, demonstrating a good predictive value for each diagnostic marker.

CONCLUSION

The current study demonstrated that IL-6, CRP, and HbA1c may be useful biomarkers to indicate diabetic foot progression. Furthermore, our findings showed a substantial relationship between CRP and HbA1c in individuals with diabetic foot conditions.

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.

[Characteristics of Inflammatory Markers in Diabetic Foot Patients and Their Relationship With Prognosis of Diabetic Foot Ulcers]

Objective

To explore the characteristics of baseline inflammatory markers in diabetic foot patients and their relationship with the prognosis of diabetic foot ulcers.

Methods

The clinical data of diabetic foot patients (n=495) admitted to West China Hospital, Sichuan University since 2016 were retrospectively collected through the hospital electronic medical record system to analyze the characteristics of inflammatory markers and their relationship with the prognosis of diabetic foot ulcers.

Results

White blood cell count (WBC), erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), procalcitonin (PCT), and interleukin-6 (IL-6) levels were significantly higher in patients defined as grade 4 on the Wagner Scale than those in patients defined as grade 0-3 on the Wagner Scale. Neutrophil percentage (NE%) was higher in Wagner grade-4 patients than those in Wagner grade-0 and grade-1 patients and higher in Wagner grade-3 patients than those in Wagner grade-0 patients. NE%, CRP, PCT, and IL-6 levels were positively correlated with the severity of diabetic foot, with the respective odds ratio (OR) at 95% confidence interval (CI) being 1.038 (1.019-1.056), 1.019 (1.012-1.026), 8.225 (2.015-33.576), and 1.017 (1.008-1.025). Using Wagner grade-0 patients as the reference, patients with higher WBC were more likely to progress to Wagner grade 2, 3, and 4, with the respective OR (95% CI) values being 1.260 (1.096-1.447), 1.188 (1.041-1.356), and 1.301 (1.137-1.490); patients with higher ESR were more likely to progress to Wagner grade 3 and 4, with the respective OR (95% CI) values being 1.030 (1.006-1.054) and 1.045 (1.019-1.071). Baseline ESR (P=0.008), CRP (P=0.039), and IL-6 (P=0.033) levels were lower in patients who had received antibiotics prior to their admission than those in patients who had not received antibiotics before admission. The levels of WBC, NE%, ESR, PCT, and IL-6 were lower in the full recovery group than those in the group of patients who did not respond to treatment. The higher the levels of NE% and IL-6, the worse the prognosis of diabetic foot ulcers became, with the respective OR (95% CI) values being 1.030 (1.010-1.051) and 1.008 (1.002-1.013).

Conclusion

The severity of diabetic foot ulcers increased with the rise in baseline levels of inflammatory markers. Elevated baseline NE% and IL-6 levels suggest a poor prognosis. Our findings suggest that early assessment of diabetic foot infection and standardized antibiotic therapy should be implemented to improve the prognosis.

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.

New insight into the virulence and inflammatory response of Staphylococcus aureus strains isolated from diabetic foot ulcers

Staphylococcus aureus strains isolated from diabetic foot ulcers (DFUs) have less virulence, but still cause severe infections. Furthermore, hypovirulent S. aureus strains appear to be localized in the deep tissues of diabetic foot osteomyelitis, indicating that the unique environment within DFUs affects the pathogenicity of S. aureus. In this study, the cell-free culture medium (CFCM) of S. aureus strains isolated from DFUs exhibited higher cytotoxicity to human erythrocytes than those isolated from non-diabetic patients with sepsis or wounds. Among these S. aureus strains isolated from DFUs, β-toxin negative strains have less virulence than β-toxin positive strains, but induced a higher expression of inflammatory cytokines. Our study and previous studies have shown that the synergistic effect of phenol-soluble modulin α and β-toxin contributes to the higher hemolytic activity of β-toxin positive strains. However, lysis of human erythrocytes by the CFCM of β-toxin negative strains was greatly inhibited by an autolysin inhibitor, sodium polyanethole sulfonate (SPS). A high level of glucose greatly reduced the hemolytic activity of S. aureus, but promoted the expression of interleukin-6 (IL-6) in human neutrophils. However, 5 mM glucose or glucose-6-phosphate (G6P) increased the hemolytic activity of SA118 (a β-toxin negative strain) isolated from DFUs. Additionally, patients with DFUs with growth of S. aureus had lower level of serum IL-6 than those with other bacteria, and the CFCM of S. aureus strains significantly reduced lipopolysaccharide-induced IL-6 expression in human neutrophils. Therefore, the virulence and inflammatory response of S. aureus strains isolated from DFUs are determined by the levels of glucose and its metabolites, which may explain why it is the predominant bacteria isolated from DFUs.

Pentraxin-3 and Other Inflammatory Markers for an Infected Diabetic Foot Ulcer Diagnosis: A Prospective Study

Strategies have been researched and implemented to reduce the number of people with diabetic foot ulcers (DFUs). One problem is the accurate assessment of DFU severity, which is the main factor in resource allocation and treatment choice. The primary objective of this study was to assess pentraxin-3 as a biomarker of an infected DFU (IDFU), the limb amputation level prognosis, and patient survival. The secondary objectives were to evaluate and compare other markers, including white blood cells (WBCs), C-reactive protein (CRP), the erythrocyte sedimentation rate (ESR), and procalcitonin (PCT), for identifying IDFUs. Over a period of two years, 145 patients were followed; 131 of these were analyzed for this study. Pentraxin-3 was found to be a good predictor of death (p = 0.047). A comparison between IDFUs and DFUs revealed the following differences: PCT had the highest AUROC of 0.91, sensitivity of 93.7, and specificity of 83.3%. CRP had a cutoff value of 226 mg/L, an AUROC of 0.89, a sensitivity of 95.5%, and a specificity of 83.3%. Fibrinogen had an AUROC of 0.87 at a cutoff value of 5.29 g/L, with a good sensitivity and specificity of 85% and 87%, respectively. ESR had a cutoff value of 46 mm/h, an AUROC of 85%, a sensitivity of 83.7%, and a specificity of 83.3%. Pentraxin-3 showed promising results in predicting IDFUs and DFUs, and it served as a marker for the risk of death in IDFU patients during the 6 month follow-up. Other markers, including CRP, PCT, ESR, and fibrinogen, were more effective in differentiating between IDFUs and DFUs.

Serum Procalcitonin (PCT) - Is there a Role as an Early Biomarker in Infected Diabetic Foot Ulcer (IDFU) Patients?

Introduction

Infected diabetic foot ulcers may lead to serious complications if not recognised in the early stage. Diagnosis of infection is particularly challenging at that stage; thus, a sensitive inflammatory biomarker may be helpful. We aimed to evaluate the role of procalcitonin (PCT) as an early biomarker for infected diabetic foot ulcers (IDFU).

Materials and method

This cross-sectional study was conducted at Klinik Rawatan Keluarga (KRK), Orthopedic clinic and wards in Hospital Universiti Sains Malaysia (USM) from May 2020 to December 2020. A total of 264 participants were recruited and divided into three groups: 50 diabetic patients with no ulcers (control), 107 patients with non-infected diabetic foot ulcers (NIDFU), and 107 patients with infected diabetic foot ulcers (IDFU). The level of PCT was taken for all patients. Total white count (TWC) and C-reactive protein (CRP) were taken only for IDFU patients. Diagnosis of infection was based on the Infectious Disease Society of America-International Working Group of Diabetic Foot (IDSA-IMWGDF), and the severity of infection was graded according to the Wagner Classification.

Results

The level of PCT was higher in IDFU than in NIDFU and diabetic patient, with a median (IQR) of 0.355 (0.63) ng/mL, 0.077 (0.15) ng/mL and 0.028 (0.02) ng/mL, respectively. PCT and CRP showed moderate positive correlations in IDFU patients (p<0.001). The sensitivity and specificity were 63.6% and 83.2%, respectively, at the best cut-off at 0.25 ng/mL.

Conclusion

PCT is a valuable biomarker for the diagnosis of infection; however, it adds little value in the early diagnosis of IDFU in view of its low sensitivity.

APPLICATION OF PROBIOTIC ANTISEPSIS FOR PURULENT COMPLICATIONS IN PATIENTS WITH TYPE 2 DIABETES MELLITUS

OBJECTIVE

The aim: To improve the results of surgical treatment of patients with type 2 diabetes and purulent-necrotic wounds by using probiotic antiseptics.

PATIENTS AND METHODS

Materials and methods: 66 patients with type 2 diabetes and purulent-necrotic complications took part in this study. Probiotic antiseptics were used for local treatment in the experimental group (n=31), and traditional antiseptics were used in the control group (n=35). The levels of pro-inflammatory markers in the blood (IL-6, TNF-a, CRP) were studied; microscopic material was taken to study the type of cytogram during bandaging, before wound treatment with antiseptics or debridement on admission to the hospital (1st day), on the 3rd day and on the 7th day.

RESULTS

Results: Analysis of dynamic changes in pro-inflammatory markers between the first and seventh days proved that only in the experimental group there was a statistically significant difference (IL-6 (Р=0.004), TNF-a (Р=0.001), CRP (Р=0.018)). Detection of regenerative-inflammatory and regenerative cytogram types on the 7th day in the experimental group had a statistically significant difference compared to the control group (p=0.002 and p<0.001, respectively).

CONCLUSION

Conclusions: the use of probiotic antisepsis accelerates wound healing in patients with type 2 diabetes and purulent-necrotic complications.

Single nucleotide variations in the development of diabetic foot ulcer: A narrative review

Diabetes mellitus has become a global health problem, and the number of patients with diabetic foot ulcers (DFU) is rapidly increasing. Currently, DFU still poses great challenges to physicians, as the treatment is complex, with high risks of infection, recurrence, limb amputation, and even death. Therefore, a comprehensive understanding of DFU pathogenesis is of great importance. In this review, we summarized recent findings regarding the DFU development from the perspective of single-nucleotide variations (SNVs). Studies have shown that SNVs located in the genes encoding C-reactive protein, interleukin-6, tumor necrosis factor-alpha, stromal cell-derived factor-1, vascular endothelial growth factor, nuclear factor erythroid-2-related factor 2, sirtuin 1, intercellular adhesion molecule 1, monocyte chemoattractant protein-1, endothelial nitric oxide synthase, heat shock protein 70, hypoxia inducible factor 1 alpha, lysyl oxidase, intelectin 1, mitogen-activated protein kinase 14, toll-like receptors, osteoprotegerin, vitamin D receptor, and fibrinogen may be associated with the development of DFU. However, considering the limitations of the present investigations, future multi-center studies with larger sample sizes, as well as in-depth mechanistic research are warranted.

A Review of Immunomodulatory Reprogramming by Probiotics in Combating Chronic and Acute Diabetic Foot Ulcers (DFUs)

Diabetic foot ulcers (DFUs) are characterized by a lack of angiogenesis and distal limb diabetic neuropathy. This makes it possible for opportunistic pathogens to protect the biofilm-encased micro-communities, causing a delay in wound healing. The acute and chronic phases of DFU-associated infections are distinguished by the differential expression of innate proinflammatory cytokines and tumor necrosis factors (TNF-α and -β). Efforts are being made to reduce the microbial bioburden of wounds by using therapies such as debridement, hyperbaric oxygen therapy, shock wave therapy, and empirical antibiotic treatment. However, the constant evolution of pathogens limits the effectiveness of these therapies. In the wound-healing process, continuous homeostasis and remodeling processes by commensal microbes undoubtedly provide a protective barrier against diverse pathogens. Among commensal microbes, probiotics are beneficial microbes that should be administered orally or topically to regulate gut-skin interaction and to activate inflammation and proinflammatory cytokine production. The goal of this review is to bridge the gap between the role of probiotics in managing the innate immune response and the function of proinflammatory mediators in diabetic wound healing. We also highlight probiotic encapsulation or nanoformulations with prebiotics and extracellular vesicles (EVs) as innovative ways to tackle target DFUs.

Extra-pulmonary applications of procalcitonin: an updated literature review

INTRODUCTION

: Procalcitonin (PCT) is a biomarker with established performance in the differentiation between bacterial and viral infections, predominantly in pulmonary infections, as well as the diagnosis and prognosis of bacterial sepsis. However, the role of PCT in extra-pulmonary infections is not well described.

AREAS COVERED

: We reviewed the role of PCT in commonly experienced extra-pulmonary infections including meningitis, diabetic foot infection, prosthetic joint infection, osteomyelitis, and skin and soft tissue infection. PubMed and Medline online libraries were searched, from 2013 till 2022, for relevant articles.

EXPERT OPINION

: For meningitis, PCT could distinguish bacterial from viral meningitis. PCT distinguished septic arthritis from different types of arthritis but had variable performance in discriminating septic arthritis from crystal arthropathy. For periprosthetic joint infections, results were inconclusive. PCT had a potential role in diagnosis of more complex infections such as osteomyelitis and diabetic foot infections, but further studies are needed for a definitive cutoff. In skin and soft tissue infections, PCT performance was more variable requiring further investigation to define cutoff for the discrimination of cellulitis from necrotizing fasciitis. We find that PCT performed best for meningitis and helps in the reduction of unnecessary antibiotic treatment, but has variable outcomes with other extra-pulmonary infections.

Improving Dietary Intake of Essential Nutrients Can Ameliorate Inflammation in Patients with Diabetic Foot Ulcers

Diabetic foot ulcers (DFUs) are classified as chronic wounds and are one of the most common complications of diabetes. In chronic wounds, management of inflammation is a key step in treatment. Nutrition plays an important role in managing and controlling inflammation. This study evaluated the effects of nutrition supplementation and education on inflammatory biomarkers in patients with DFUs. Eligible patients with foot ulcers were randomly assigned to either a treatment (n = 15) or control group (n = 14). Both groups received standard care for wound treatment from the clinic; however, the treatment group was also provided with nutritional supplementation and education. Plasma concentrations of inflammatory biomarkers, namely C-reactive protein (CRP), interleukin 6 (IL6), interleukin 10 (IL10), and tristetraprolin (TTP), were evaluated at baseline and every four weeks, until complete wound closure had occurred or up to 12 weeks. The mean plasma concentration of IL6 significantly decreased in the treatment group (p = 0.001). The interaction between time and group was not statistically significant for the mean plasma concentrations of CRP, IL10, and TTP during the 12 weeks of the study. The results of this study showed the positive effects of nutritional intervention on controlling inflammation in DFU patients. More clinical trials with a larger population and longer duration of time are needed to confirm our results.

The efficacy of inflammatory markers in diagnosing infected diabetic foot ulcers and diabetic foot osteomyelitis: Systematic review and meta-analysis

Background

Diabetes foot ulcer (DFU) is a complication of diabetes mellitus. Accurate diagnosis of DFU severity through inflammatory markers will assist in reducing impact on quality of life. We aimed to ascertain the diagnostic test accuracy of commonly used inflammatory markers such as erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), procalcitonin (PCT), and white cell count (WCC) for the diagnosis and differentiation between DFU grades based on the International Working Group on the Diabetic Foot classification system.

Methods

This systematic review explored studies that investigated one or more of the above-listed index tests aiding in diagnosing infected DFU. This review was registered on PROSPERO database (ID = CRD42021255618) and searched 5 databases including an assessment of the references of included studies. Records were manually screened as per Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines. A total of 16 studies were included which were assessed for quality using QUADAS-2 tool and meta-analysed using Meta-Disc v1.4.

Results

CRP had the greatest area under the curve (AUC) of 0.893 for diagnosing grade 2 DFU. This returned a pooled sensitivity and specificity of 77.4% (95% CI: 72% to 82%) and 84.3% (95% CI: 79% to 89%) respectively. In terms of diagnosing grade 3 DFU, procalcitonin had the highest AUC value of 0.844 when compared with other markers. The pooled sensitivity of PCT was calculated as 85.5% (95% CI: 79% to 90%) and specificity as 68.9% (95% CI: 63% to 75%).

Conclusion

CRP and PCT are the best markers for diagnosing grade 2 and grade 3 DFU respectively. Other markers are also valuable when used in conjunction with clinical judgement. The findings accentuate the necessity of further research to establish standardised cut-off values for these inflammatory markers in diagnosing diabetic foot ulcers.

Qingwei San treats oral ulcer subjected to stomach heat syndrome in db/db mice by targeting TLR4/MyD88/NF-κB pathway

Background

Qingwei San (QWS), one of classic Chinese Medicine prescripts, has been widely used to treat stomach heat syndrome which manifests oral ulcer (OU), periodontitis and upper gastrointestinal bleeding for seven hundred years. However, the therapeutic effects of QWS on diabetic OU subjected to stomach heat syndrome are still ambiguous. In the study, we investigated the pharmacological mechanisms.

Methods

The main components of QWS aqueous extract were analyzed by LC–MS, and potential pathways of QWS targeting OU were predicted by network pharmacology. The db/db mice were administered with the decoction of dried Zingiber officinale Rosc. rhizome combined with NaOH cauterization to establish the model of diabetic OU subjected to stomach heat syndrome. Subsequently, the model mice were treated with QWS, and OU wound healing status were recorded. The pathological changes of gastric tissue and oral mucosa were evaluated using hematoxylin–eosin staining, and the morphology of collagen fibers in oral mucosa was assessed by Masson staining. The levels of thromboxane B₂ (TXB₂), 6-Keto-prostaglandin F1α (6-keto-PGF1α), interleukin-1 β (IL-1β), IL-2, IL-6, tumor necrosis factor-α (TNF-α), β-endorphin (β-EP) and 5-Hydroxytryptamine (5-HT) were determined by ELISA assay. The protein expressions of Toll-like receptor 4 (TLR4), TNF receptor associated factor 6 (TRAF6), myeloid differentiation factor 88 (MyD88), inhibitor of NF-κB alpha (IκΒα), p-IκΒα and nuclear factor kappa-B (NF-κB) p65 were measured by Western Blotting.

Results

A total of 183 compounds in QWS were identified by LC–MS, and identified 79 bioactive compounds corresponded to 269 targets and 59 pathways. QWS high-dose treatment significantly reduced the level of TXB₂ and the ratio of TXB₂/6-keto-PGF1α. Meanwhile, it improved mucosal pathological morphology, and reduced the area of OU and local edema. Simultaneously, the levels of TNF-α, IL-1β, IL-6, IL-2 and 5-HT, and the expressions of TLR4, TRAF6, MyD88, p-IκΒα and NF-κB p65 were decreased.

Conclusion

QWS treatment facilitates the healing of OU, ameliorates pathological morphologies of gastric and oral mucosa and decreases the levels of pro-inflammatory cytokines in db/db mice subjected to stomach heat syndrome, whose mechanism may be associated with the inhibition of TLR4/MyD88/NF-κB signaling pathway to exert anti-inflammatory effects.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13020-021-00565-5.

The Construction and Analysis of Infiltrating Immune Cell and ceRNA Networks in Diabetic Foot Ulcer

BACKGROUND

Diabetic foot ulcer (DFU) is a severe complication characterized by low-grade infectious inflammation and probably associated with specific competitive endogenous RNAs (ceRNAs) and infiltrating immune cells. Nonetheless, no reliable biomarkers are used for detecting infectious inflammation in DFU. Therefore, it is essential to explore potential biomarkers for the accurate diagnosis and treatment of DFU.

METHODS

The gene expression profile was retrieved from Gene Expression Omnibus (GEO) database and divided into two groups, namely, standard samples and DFU samples. To establish the ceRNA networks, Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses were utilized to analyze differential expression genes (DEGs). The cell type identification was achieved by estimating relative subsets of RNA transcripts (CIBERSORT) algorithm to screen-specific immune-infiltrating cells associated with DFU.

RESULTS

A ceRNA network was constructed with 20 differential expression circRNA (DEcircRNAs), 11 differential expression microRNAs (DEmiRNAs), and 9 differential expression mRNAs (DEmRNAs). Functional enrichment analysis demonstrated that DFU was mainly enriched in vascular endothelial growth factor (VEGF) and T-cell receptor signaling. In addition, CIBERSORT estimation indicated that CD8⁺ T cells and Monocytes were significantly related to the expression of IL-6, a DFU-specific infectious inflammation factor.

CONCLUSION

This study identified that some significant ceRNAs (JUNB, GATA3, hsa-circ-0049271 and hsa-circ-0074559) and infiltrating immune cells (CD8⁺ T cells and monocytes) might be related to DFU infectious inflammation.

The effect of rheopheresis treatment on the cytokine profile in diabetic foot syndrome with hyperviscosity in the aspect of clinical changes: A preliminary study

BACKGROUND

Rheopheresis is a selective extracorporal double cascade filtration treatment, which can extract high molecular weight proteins being responsible for hyperviscosity. As the whole blood and plasma viscosity decrease microcirculation improves.

OBJECTIVE

In this preliminary study we aimed to analyze additional beneficial effects of rheopheresis treatment with changes of pro-inflammantory cytokine levels in diabetic foot syndrome patients.

METHODS

Two rheopheresis treatments were performed for 6 patients with diabetic foot ulcer and/or neuropathy on consecutive days. Before and after the treatments whole blood and plasma viscosity, as well as IL-6, IL-8, and TNF-alpha serum levels were determined, and complex angiological and ENG examinations were performed.

RESULTS

Rheopheresis decreased the whole blood and plasma viscosity, and the serum levels of IL-6, IL-8, and TNF-alpha were markedly reduced. The life quality of the patients improved, the ulcers healed, the pain decreased. Daily dose of analgesics decreased in the follow-up period (6 months). The ENG showed improving amplitude and/or normalizing conduction speed.

CONCLUSION

Application of rheopheresis in patients with diabetic foot syndrome has a beneficial effect, providing favorable rheological condition, normalizing cytokine profile and reducing the sensorineural symptoms.

Diabetic Wound-Healing Science

Diabetes mellitus is an increasingly prevalent chronic metabolic disease characterized by prolonged hyperglycemia that leads to long-term health consequences. It is estimated that impaired healing of diabetic wounds affects approximately 25% of all patients with diabetes mellitus, often resulting in lower limb amputation, with subsequent high economic and psychosocial costs. The hyperglycemic environment promotes the formation of biofilms and makes diabetic wounds difficult to treat. In this review, we present updates regarding recent advances in our understanding of the pathophysiology of diabetic wounds focusing on impaired angiogenesis, neuropathy, sub-optimal chronic inflammatory response, barrier disruption, and subsequent polymicrobial infection, followed by current and future treatment strategies designed to tackle the various pathologies associated with diabetic wounds. Given the alarming increase in the prevalence of diabetes, and subsequently diabetic wounds, it is imperative that future treatment strategies target multiple causes of impaired healing in diabetic wounds.

Comparative Evaluation of the Diagnostic Value of Procalcitonin and hsCRP for the Presence of Mild-to-Moderate Diabetic Foot Infections

The aim of this study is to compare the efficacy of procalcitonin (PCT) and high-sensitive C-reactive protein (hsCRP) as diagnostic biomarkers in patients with diabetes and mild-to-moderate diabetic foot infections. A total of 119 patients (102 with type 2 diabetes and 17 with type 1 diabetes), of mean age 60.29 ± 10.05 years, divided into 3 groups-diabetic foot ulcer (DFU) with active infection (IDFU group, n = 41), DFU without clinical signs of infection (non-IDFU group, n = 35), and a control group with diabetes without DFU (n = 43). Infection severity was graded according to the International Working Group on the Diabetic Foot guideline-non-IDFU group as Grade 1, IDFU group as Grade 2 (n = 22), and Grade 3 (n = 19). Serum hsCRP was assessed by the immunoturbidimetric method and PCT by the enzyme chemiluminescence immunoassay (ECLIA) method. Levels of white blood cells (WBC) were assessed using the Medonic hematology analyzer and erythrocyte sedimentation rate (ESR) by the Westergren method. Serum hsCRP, WBC count, and ESR were significantly higher in the IDFU group as compared to non-IDFU and control groups, whereas PCT levels did not differ between the groups. hsCRP presented with higher sensitivity (80%), specificity (79%), area under the curve (AUC) 0.856, in comparison to PCT (sensitivity 63%, specificity 62%, AUC 0.617) for the presence of IDFU, as well as in the Grade 3 subgroup (84% sensitivity and specificity, AUC 0.911). The combined model of both markers did not present with better accuracy than using hsCRP alone. In conclusion, hsCRP appears to be a better diagnostic biomarker than PCT in the diagnosis of moderate foot ulcer infection. Both markers fail to distinguish mild infection.

An update on potential biomarkers for diagnosing diabetic foot ulcer at early stage

As one of major chronic complications of diabetes, diabetic foot ulcer (DFU) is the main cause of disability and death. The clinical diagnosis and prognosis of DFU is inadequate. For clinicians, if the risk stratification of DFU can be obtained earlier in diabetic patients, the hospitalization, disability and mortality rate will be reduced. In addition to the inflammatory biomarkers that have been widely concerned and used, e.g., procalcitonin, pentraxin-3, C-reactive protein (CRP), interleukins (ILs), and tumor necrosis factor-α (TNF-α), etc., a more comprehensive prediction of the risk and severity of DFU is needed to reflect new biomarkers for therapeutic intervention effects. Along with the development of systems biology technology, genomics, proteomics, metabolomics and microbiome have been used in the studies on DFU for better understanding of the disease. In this review, new biomarkers that are expected to assist in the accurate diagnosis and risk stratification of DFU will be discussed and summarized in detail.

Role of Nrf2 in MALAT1/ HIF-1α loop on the regulation of angiogenesis in diabetic foot ulcer

Diabetic non healing wounds often result in significant morbidity and mortality. The number of effective targets to detect these wounds are meagre. Slow lymphangiogenesis is one of the complex processes involved in impaired healing of wounds. Long non coding RNAs (lncRNAs) have been importantly recognized for their role in pathological conditions. Multiple studies highlighting the role of lncRNAs in the regulation of several biological processes and complex diseases. Herein, we investigated the role of lncRNA Metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) in the progression of diabetic foot ulcer (DFU). We report a significant reduction in the expression of lncRNA MALAT1 in the infected DFU subjects which was positively correlated with the expression of angiogenic factors such as Nrf2, HIF-1α and VEGF. Further, expression of pro-inflammatory markers TNF-α and IL-6 were found to be increased while, the expression of anti-inflammatory marker IL-10 was decreased in infected DFU tissues. Involvement of lncRNA MALAT1 in angiogenesis in EA.hy926 cells was demonstrated by silencing the expression of Nrf2, HIF-1α, and VEGF through interference mediated by MALAT1. In addition, its inflammatory role was demonstrated by decreased expression of TNF-α, IL-6 and not affecting the expression of IL-10. Further, CRISPR-Cas9 knock out of Nrf2 decreased the expression of lncRNA MALAT1, HIF-1α and VEGF which revealed the association of Nrf2 in regulating MALAT1/HIF-1α loop through positive feedback mechanism. Collectively, our results suggested the role of Nrf2 on MALAT1/HIF-1α loop in the regulation of angiogenesis, which could act as a novel target in the treatment of diabetic wounds.

Microbiome-skin-brain axis: A novel paradigm for cutaneous wounds

Chronic wounds cause a significant burden on society financially, medically, and psychologically. Unfortunately, patients with nonhealing wounds often suffer from comorbidities that further compound their disability. Given the high rate of depressive symptoms experienced by patients with chronic wounds, further studies are needed to investigate the potentially linked pathophysiological changes in wounds and depression in order to improve patient care. The English literature on wound healing, inflammatory and microbial changes in chronic wounds and depression, and antiinflammatory and probiotic therapy was reviewed on PubMed. Chronic wound conditions and depression were demonstrated to share common pathologic features of dysregulated inflammation and altered microbiome, indicating a possible relationship. Furthermore, alternative treatment strategies such as immune-targeted and probiotic therapy showed promising potential by addressing both pathophysiological pathways. However, many existing studies are limited to a small study population, a cross-sectional design that does not establish temporality, or a wide range of confounding variables in the context of a highly complex and multifactorial disease process. Therefore, additional preclinical studies in suitable wound models, as well as larger clinical cohort studies and trials are necessary to elucidate the relationship between wound microbiome, healing, and depression, and ultimately guide the most effective therapeutic and management plan for chronic wound 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.

Pro-Calcitonin, Erythrocyte Sedimentation Rate and C - reactive Protein in Predicting Diabetic Foot Ulcer Characteristics; a Cross Sectional Study

INTRODUCTION

Considering the importance of early diagnosis of diabetic foot ulcers and its complications, this study aimed to evaluate the accuracy of erythrocyte sedimentation rate (ESR), C - reactive protein (CRP), and pro-calcitonin (PCT) in predicting the ulcer class, osteomyelitis, and peripheral arterial disease (PAD).

METHODS

This cross-sectional study was performed on 200 consecutive patients suffering from diabetic foot ulcer who were referred to Infectious Disease Ward. The levels of PCT, ESR, and CRP were measured for all patients and the screening performance characteristics of each marker in predicting the ulcer class, osteomyelitis, and PAD was calculated.

RESULTS

The levels of PCT, ESR and CRP were significantly higher in patients with class IV foot ulcer compared to those with class III ulcers (p<0.001). Patients with evidence of osteomyelitis had significantly higher level of PCT, ESR and CRP. The best cutoff points of PCT, ESR and CRP in predicting osteomyelitis were 0.35 ng/ml (86.1% sensitivity, 45.3% specificity), 56.5 mm/hours (95.8% sensitivity, and 50.0% specificity) and 44 mg/ml (90.3% sensitivity, 57.0% specificity), respectively. The presence of PAD was significantly associated with increased levels of the three biomarkers. The best cutoff values for PCT, ESR and CRP in predicting PAD were 0.45 (70.8% sensitivity, 71.7% specificity), 61.5 (83.3% sensitivity, 52.0% specificity) and 49 (83.3% sensitivity, 63.8% specificity), respectively.

CONCLUSION

Based on the findings of the present study, although the accuracy of PCT, ESR, and CRP in predicting the severity of diabetic foot ulcers was fair, increase in the three parameters can predict the occurrence of osteomyelitis and PAD following diabetic food development with good accuracy and acceptable sensitivity.