Clinical predictors of treatment failure for diabetic foot infections: data from a prospective trial

Predictive Factors of Amputation in Diabetic Foot

Background: Diabetic foot ulcers are a common complication of diabetes mellitus, often leading to progressive sensory deficits, impaired vascularization, and a predisposition to ulceration and gangrene. Untreated ulcers may cause recurrent infections that endanger a patient's life. Amputation of part of the limb up to a well-vascularized level is one of the treatments employed for untreated ulcers. Objectives: Laboratory data were analyzed with the aim of identifying risk factors related to surgical amputation treatment of diabetic foot. We believe it is useful to identify risk factors that can be altered from a reversible condition in the clinical decision-making of treatment, thus manifesting themselves in a timely manner to provide the patient with an alternative to surgical amputation of the lower limb. Methods: Our retrospective study was conducted by the Department of Orthopedics and Traumatology at the Fondazione Policlinico Universitario Agostino Gemelli IRCCS in Rome. We recruited 200 patients who underwent lower limb amputation for diabetic foot between 2017 and 2021 and had blood tests both 30 days and within 5 days before the first surgery. Results: This case-control study revealed a significant negative correlation between hemoglobin (Hb) levels and the occurrence of leg amputations. In contrast, C-reactive protein (CRP) levels, the neutrophil-to-lymphocyte ratio (NLR), and the platelet-to-lymphocyte ratio (PLR) showed significant positive correlations with leg amputations. A 3-year follow-up of the cases also revealed a significative positive correlation between age, white blood cells (WBC) count, NLR, PLR, and death at 3 years. Conclusions: Our findings suggested that lower Hb levels and elevated CRP, NLR, and PLR levels in patients with diabetic foot disease may be associated with a higher risk of lower-limb amputation. Unexpectedly, this study also demonstrated that elderly age, WBC, CRP, NLR and PLR levels may be associated with a negative prognosis for these patients. These findings highlighted the importance of monitoring these laboratory values in diabetic patients to identify individuals at higher risk of leg amputations and implement appropriate interventions to prevent or minimize the occurrence of this severe complication.

Analysis of factors influencing the recurrence of diabetic foot ulcers

OBJECTIVE

The aim of this study is to investigate the factors influencing the recurrence of diabetic foot ulcers (DFU) and provide guidance for reducing the recurrence rate.

METHODS

A total of 211 patients diagnosed with DFU who were hospitalized and discharged from the hospital from October 2015 to January 2020 were included as the study cohort. Participants were divided into two groups according to whether the foot ulcer recurred during the 2-year follow-up period: a recurrence group (n = 84) and a non-recurrence group (n = 127). The following data were collected and analyzed for the two groups of patients: general information, foot information, laboratory indicators, diabetes comorbidities, and complications.

RESULTS

(1) The overall recurrence rate of diabetic foot ulcers (DFU) within 2 years was 39.8%, indicating a high recurrence rate. (2) Significant differences were observed between the two patient groups in terms of BMI, HbA1c, TBIL, CRP, financial situation, foot deformity, first ulcer on the sole of the foot, previous amputation history, Wagner grade of the first ulcer, osteomyelitis, DFU duration (>60 days), lower limb vascular reconstruction, peripheral arterial disease (PAD), and diabetic peripheral neuropathy (DPN) (t = 2.455; Z = -1.988, -3.731, -3.618; χ2 = 7.88, 5.004, 3.906, 17.178, 16.237, 5.007, 24.642, 4.782, 29.334, 10.253). No significant differences were found for the other indicators. (3) Logistic regression analysis revealed that TBIL (OR = 0.886, p = 0.036) was a protective factor against ulcer recurrence. In contrast, PAD, previous amputation history, DPN, and the first ulcer on the sole of the foot (OR = 3.987, 6.758, 4.681, 2.405; p < 0.05 or p < 0.01) were identified as risk factors for ulcer recurrence.

CONCLUSION

Early screening and preventive education targeting high-risk factors such as DPN, PAD and the initial ulcer location on the sole of the foot are essential to mitigate the high long-term recurrence rate of DFU. Furthermore, the protective role of TBIL in preventing ulcer recurrence underscores the importance of monitoring bilirubin levels as part of a comprehensive management strategy for DFU patients.

The Efficacy of Diabetic Foot Treatment in a "TOSF" Pattern: A Five-Year Retrospective Study

Aim

To evaluate the advantages and problems in the diagnosis and treatment of diabetic foot (DF) patients by analyzing the results of a 5-year follow-up of the organ system based (TOSF) treatment model.

Methods

A retrospective study was conducted in 229 patients with diabetic foot. Chi-square test and rank-sum test were used to analyze the effects of patients' general condition, behavioral and nutritional status, degree of infection (inflammatory markers), comorbidity, diabetic foot grade/classification, and revascularization on readmission rate, amputation rate, all-cause mortality, incidence of other complications, and wound healing time. Logistic regression was used to analyze the risk factors affecting the prognosis of diabetic foot. Kaplan-Meier survival curve was used to analyze the differences in amputation rate and mortality rate at each time point.

Results

This study showed that nutritional status, degree of infection, and revascularization influenced readmission rates. General condition, behavior and nutritional status, degree of infection, Wagner grade and revascularization affect the amputation rate. General conditions, behavioral and nutritional status, degree of infection, comorbidities, classification and revascularization affect the mortality of patients. Age and white blood cell(WBC) count affected the incidence of other complications. Influence of infection degree and Wagner grade and revascularization in patients with wound healing time. Revascularization was an independent protective factor for readmission, amputation, and mortality.Elevated serum inflammatory markers are an independent risk factor for amputation. Hypoproteinemia is an independent risk factor for mortality.

Conclusion

In the "TOSF" diagnosis and treatment pattern, diabetic foot patients have a good prognosis. Special attention should be paid to the screening and revascularization of lower extremity vascular disease in patients with diabetic foot.

An Overview of Risk Factors for Diabetic Foot Amputation: An Observational, Single-centre, Retrospective Cohort Study

INTRODUCTION

Not only are early detection and treatment of diabetic foot ulcers important, but also acknowledging potential risk factors for amputation gives clinicians a considerable advantage in preventing amputations. Amputations impact both healthcare services and the physical and mental health of patients. This study aimed to investigate the risk factors for amputation in patients with diabetic foot ulcers.

METHODS

The sample for this study was patients with diabetic foot ulcers who were treated by the diabetic foot council at our hospital between 2005 and 2020. A total of 32 risk factors for amputation were identified and investigated among 518 patients.

RESULTS

Our univariate analysis showed that 24 of 32 defined risk factors were statistically significant. In the multivariate analysis using the Cox regression model, seven risk factors remained statistically significant. The risk factors most significantly associated with amputation were Wagner grading, abnormal peripheral arteries, hypertension, high thrombocyte levels, low haematocrit levels, hypercholesterolaemia and male sex, respectively. The most common cause of death in patients with diabetes who have undergone amputation is cardiovascular disease, followed by sepsis.

CONCLUSION

To enable optimum treatment of patients with diabetic foot ulcers it is important for physicians to be aware of the amputation risk factors, and thus avoid amputations. Correcting risk factors, using suitable footwear and routinely inspecting feet are crucial factors for preventing amputations in patients with diabetic foot ulcers.

Machine Learning Models for Predicting the Risk of Hard-to-Heal Diabetic Foot Ulcers in a Chinese Population

BACKGROUND

Early detection of hard-to-heal diabetic foot ulcers (DFUs) is vital to prevent a poor prognosis. The purpose of this work was to employ clinical characteristics to create an optimal predictive model of hard-to-heal DFUs (failing to decrease by >50% at 4 weeks) based on machine learning algorithms.

METHODS

A total of 362 DFU patients hospitalized in two tertiary hospitals in eastern China were enrolled in this study. The training dataset and validation dataset were split at a ratio of 7:3. Univariate logistic analysis and clinical experience were utilized to screen clinical characteristics as predictive features. The following six machine learning algorithms were used to build prediction models for differentiating hard-to-heal DFUs: support vector machine, the naïve Bayesian (NB) model, k-nearest neighbor, general linear regression, adaptive boosting, and random forest. Five cross-validations were employed to realize the model's parameters. Accuracy, precision, recall, F1-scores, and AUCs were utilized to compare and evaluate the models' efficacy. On the basis of the best model identified, the significance of each characteristic was evaluated, and then an online calculator was developed.

RESULTS

Independent predictors for model establishment included sex, insulin use, random blood glucose, wound area, diabetic retinopathy, peripheral arterial disease, smoking history, serum albumin, serum creatinine, and C-reactive protein. After evaluation, the NB model was identified as the most generalizable model, with an AUC of 0.864, a recall of 0.907, and an F1-score of 0.744. Random blood glucose, C-reactive protein, and wound area were determined to be the three most important influencing factors. A corresponding online calculator was created (https://predicthardtoheal.azurewebsites.net/).

CONCLUSION

Based on clinical characteristics, machine learning algorithms can achieve acceptable predictions of hard-to-heal DFUs, with the NB model performing the best. Our online calculator can assist doctors in identifying the possibility of hard-to-heal DFUs at the time of admission to reduce the likelihood of a dismal prognosis.

Risk Factors Associated with 30-Day Readmission in Patients with Diabetic Foot Infections

BACKGROUND

Diabetic foot infections (DFIs) are the most common cause of hospitalization for patients with diabetes. Studies have shown diabetic patients have high readmission rates. It is important to identify variables that contribute to readmission. This study aimed to investigate clinical variables associated with 30-day hospital readmission in patients with DFI.

METHODS

We conducted a retrospective study of adults admitted to the hospital for DFI between July 1, 2012, and July 1, 2015. We identified patients by International Classification of Diseases, Ninth Revision codes and randomly selected 35% of medical records for review. Patients were excluded if they did not have a DFI by review, were pregnant, or were incarcerated. The primary outcome was 30-day readmission. Data collected included baseline demographics, medical comorbidities, substance abuse, homelessness, tobacco use, and laboratory and surgical pathology data. Univariate and multivariate logistic regression models were used to identify independent predictors.

RESULTS

Of 140 included patients, 106 (76%) were male. Median age was 55 years and length of stay (LOS) was 7 days. In univariate analysis, 31 patients (22%) were readmitted in the 30 days after the index hospitalization. Factors associated with readmission included treatment failure, elevated C-reactive protein level, and hospital LOS (P < .05). In multivariate analyses, LOS and treatment failure were independent predictors of readmission.

CONCLUSIONS

The 30-day readmission rate for patients with DFI is high. Treatment failure, C-reactive protein, and LOS are independently associated with readmission. More work is needed to determine reasons for readmission so that appropriate measures can be taken before discharge.

Analysis of routine blood markers for predicting amputation/re-amputation risk in diabetic foot

Diabetic foot is challenging progressive disease which requires multisystemic control. Neuropathy, arteriopathy, and cellular responses should treated collaboratively. Despite all medical advances, diabetic foot can highly resulted with amputation and also re-amputation can be required because of failed wound healing. In this study, we aimed to investigate the relation between blood parameters and amputation events. Diabetic 323 patients include to the study who referred to orthopaedic clinic for amputation. Amputation levels (amputation levels phalanx, metatarsal, lisfranc, syme, below knee, knee-disarticulation, above-knee amputation) and re-amputations recorded and compared with routine blood parameters. Re-amputation was observed at 69 patients. The significant difference detected between lower albumin, higher HbA1c, higher CRP levels (P < 0.05) in regards to gross amputation levels, and increased wound depth. Furthermore, lower albumin levels and higher levels of WBC, HbA1c, CRP, and Creatinine were detected in re-amputation levels. Especially, HbA1c, CRP, and Creatinine levels were found as upper bound of reference line for re-amputation. The statistically optimal HbA1c cutoff point for diabetes was ≥7.05%, with a sensitivity of 86% and a specificity of 59%. In according to our results, simple blood parameters can be useful for observing the progress of amputation in diabetic foot. Particularly, lower albumin, and higher HbA1c, CRP, and Creatinine levels detected as related with poor prognosis. Besides, screening of HbA1c level seems to be highly sensitive for detecting of re-amputation possibility.

The role of the platelet-to-lymphocyte ratio and neutrophil-to-lymphocyte ratio in the prediction of length and cost of hospital stay in patients with infected diabetic foot ulcers: A retrospective comparative study

OBJECTIVE

The aim of this study was to determine the role of new inflammatory markers, including the platelet-to-lymphocyte ratio (PLR) and neutrophil-to-lymphocyte ratio (NLR), in the prediction of length and cost of hospital stay in patients with infected diabetic foot ulcers (DFUs).

METHODS

A total of 78 patients with DFUs who were admitted to our endocrinology clinic between January 2016 and July 2017 were included. Patients were then divided into three groups according to the Wagner DFU classification system: group 1: 18 patients with grade 2 DFU (11 men, 7 women; mean age = 57.5±7 years); group 2: 44 patients with grade 3 DFU (18 men, 26 women; mean age = 59.7±8.7 years); and group 3: 16 patients with grade 4 DFU (10 men, 6 women; mean age = 59.9±11.6 years). Laboratory findings were retrospectively obtained from hospital records; the PLR and NLR were calculated in all groups. Length and cost of hospital stay were recorded. Hospital costs were estimated in Turkish Lira (TL) based on the evaluation of glucose regulation, wound care, and antibiotic treatment.

RESULTS

The mean NLR was significantly lower in group 1 (2.8±0.9) than in group 2 (6.0±5.2; p=0.017) and group 3 (6.9±5.3; p=0.011). The mean PLR was significantly lower in group 1 (140.8±42.6) than in group 3 (222.1±95.5; p=0.006). The mean length of stay was 7.9±2.7 days in group 1, 15.0±8.9 days in group 2, and 12.5±8.9 days in group 3. The mean cost was 1,310.8±500 TL in group 1, 2,966.9±2105 TL in group 2, and 3,488.1±3603.1 TL in group 3. Length and cost of stay were both significantly lower in group 1 than in groups 2 and 3 (p=0.011 and p=0.002, respectively). Comparative results showed that the length and cost of hospital stay increased with increasing severity of DFUs. Furthermore, correlation analyses demonstrated no correlation of length of stay with PLR and NLR but an obvious correlation between cost of stay and PLR (r=0.412; p<0.001). Additionally, there was no correlation between cost of stay and NLR (r=0.158, p>0.05).

CONCLUSION

The PLR is inflammatory marker that can be measured by an inexpensive and easily accessible test and can aid in the prediction of length and cost of hospital stay in patients with DFUs.

LEVEL OF EVIDENCE

Level III, Therapeutic study.

Predictors of lower extremity amputation in patients with diabetic foot ulcer: findings from MEDFUN, a multi-center observational study

Background

Lower extremity amputation (LEA) is a potential sequelae of diabetic foot ulceration (DFU) and is associated with huge morbidly and mortality. Low and middle income countries are currently at the greatest risk of diabetes-related complications and deaths. We sought to identify demographic, clinical and laboratory variables that significantly predict LEA in patients hospitalized for DFU.

Methods

The Multi-center Evaluation of Diabetic Foot Ulcer in Nigeria (MEDFUN) was an observational study conducted between March 2016 and April 2017 in six tertiary healthcare institutions. We prospectively followed 336 diabetic patients hospitalized for DFU and managed by a multidisciplinary team until discharge or death. Demographic and diabetes-related information and ulcer characteristics were documented. Patients were evaluated for neuropathy, peripheral arterial disease (PAD) and medical co-morbidities while relevant laboratory and imaging tests were performed. The study end-points were ulcer healing, LEA, duration of hospitalization and mortality. Here we present data on amputation.

Results

One hundred and nineteen subjects (35.4%) underwent LEA during the follow-up period. Univariate predictors of LEA were ulcer duration more than 1 month prior to hospitalization (P <  0.001), PAD (P <  0.001), Wagner grade ≥ 4 (P <  0.001), wound infection (P 0.041), Proteinuria (P 0.021), leucocytosis (P 0.001) and osteomyelitis (P <  0.001). On multivariate regression, only three variables emerged as significant independent predictors of LEA and these include: ulcer duration more than 1 month (O.R. 10.3, 95% C.I. 4.055–26.132), PAD (O.R. 2.8, 95% C.I. 1.520–5.110) and presence of osteomyelitis (O.R. 5.6, 95% C.I. 2.930–10.776). Age, gender, diabetes type and duration, neuropathy, glycemic control and anemia did not predict LEA in the studied population.

Conclusion

We identified duration of ulcer greater than 1 month, PAD, Wagner grade 4 or higher, proteinuria, leucocytosis, wound infection and osteomyelitis as the significant predictors of LEA in patients hospitalized for DFU. Prompt attention to these risk factors may reduce amputation rate among these patients.

Risk Factors for Below-the-Knee Amputation in Diabetic Foot Osteomyelitis After Minor Amputation

BACKGROUND

Below-the-knee amputation (BKA) can be a detrimental outcome of diabetic foot osteomyelitis (DFO). Ideal treatment of DFO is controversial, but studies suggest minor amputation reduces the risk of BKA. We evaluated risk factors for BKA after minor amputation for DFO.

METHODS

This is a retrospective cohort of patients discharged from Denver Health Medical Center from February 1, 2012, through December 31, 2014. Patients who underwent minor amputation for diagnosis of DFO were eligible for inclusion. The outcome evaluated was BKA in the 6 months after minor amputation.

RESULTS

Of 153 episodes with DFO that met the study criteria, 11 (7%) had BKA. Failure to heal surgical incision at 3 months (P < .001) and transmetatarsal amputation (P = .009) were associated with BKA in the 6 months after minor amputation. Peripheral vascular disease was associated with failure to heal but not with BKA (P = .009). Severe infection, bacteremia, hemoglobin A_1c, and positive histopathologic margins of bone and soft tissue were not associated with BKA. The median antibiotic duration was 42 days for positive histopathologic bone resection margin (interquartile range, 32-47 days) and 16 days for negative margin (interquartile range, 8-29 days). Longer duration of antibiotics was not associated with lower risk of BKA.

CONCLUSIONS

Patients who fail to heal amputation sites in 3 months or who have transmetatarsal amputation are at increased risk for BKA. Future studies should evaluate the impact of aggressive wound care or whether failure to heal is a marker of another variable.

Clinical and surgical characteristics of infected diabetic foot ulcers in a tertiary hospital of Mexico

Background: The objective of this study was to determine the clinical and surgical characteristics of diabetic foot ulcers in a tertiary level hospital in Mexico. Methods: We performed a longitudinal, descriptive study from July, 2012 to August, 2015 on a sample composed of 100 patients with type 2 diabetes mellitus and infected diabetic foot ulcers. We analyzed socio-demographic variables, comorbidities, characteristics of ulcers, and the applied treatment. Results: We found that the most affected areas were the forefoot (48%) and the plantar region (55%) of the foot. Also, most of the patients arrived with advanced stages of diabetic foot ulcers, since 93% of the lesions were of grades III-V according to the Wagner classification. Moreover, lesions usually present with advanced states of infection, since 60% of the lesions were of grades 3-4 in the PEDIS scale. In addition, the great majority of the patients are prone to complications because we found that 43% of the patients suffered from hypertension, 47% of the patients had chronic kidney disease, and 45% reported smoking. In fact, 45% of the patients eventually suffered an amputation. We also found that the situation is more difficult because the great majority of the patients (96%) have a low level of education and very low income and they do not have any health insurance. Nevertheless, we also found that an efficient treatment can help in avoiding amputations, since 53% of grade IV and 25% of grade V lesions according to the Wagner system did not suffer an amputation. Conclusions: Therefore, an effective antibiotic treatment and an education of the patient on the adequate care of their lesions are essential in increasing the welfare of patients, especially when they have a low level of education.

Incidence and risk factors for developing infection in patients presenting with uninfected diabetic foot ulcers

OBJECTIVE

There is a paucity of research on patients presenting with uninfected diabetic foot ulcers (DFU) that go on to develop infection. We aimed to investigate the incidence and risk factors for developing infection in a large regional cohort of patients presenting with uninfected DFUs.

METHODS

We performed a secondary analysis of data collected from a validated prospective state-wide clinical diabetic foot database in Queensland (Australia). Patients presenting for their first visit with an uninfected DFU to a Diabetic Foot Service in one of thirteen Queensland regions between January 2012 and December 2013 were included. Socio-demographic, medical history, foot disease history, DFU characteristics and treatment variables were captured at the first visit. Patients were followed until their DFU healed, or if their DFU did not heal for 12-months, to determine if they developed a foot infection in that period.

RESULTS

Overall, 853 patients were included; mean(standard deviation) age 62.9(12.8) years, 68.0% male, 90.9% type 2 diabetes, 13.6% indigenous Australians. Foot infection developed in 342 patients for an overall incidence of 40.1%; 32.4% incidence in DFUs healed <3 months, 55.9% in DFUs healed between 3-12 months (p<0.05). Independent risk factors (Odds Ratio (95% confidence interval)) for developing infection were: DFUs healed between 3-12 months (2.3 (1.6-3.3)), deep DFUs (2.2 (1.2-3.9)), peripheral neuropathy (1.8 (1.1-2.9)), previous DFU history (1.7 (1.2-2.4)), foot deformity (1.4 (1.0-2.0)), female gender (1.5 (1.1-2.1)) and years of age (0.98 (0.97-0.99)) (all p<0.05).

CONCLUSIONS

A considerable proportion of patients presenting with an uninfected DFU will develop an infection prior to healing. To prevent infection clinicians treating patients with uninfected DFUs should be particularly vigilant with those presenting with deep DFUs, previous DFU history, peripheral neuropathy, foot deformity, younger age, female gender and DFUs that have not healed by 3 months after presentation.

Comparison of five systems of classification of diabetic foot ulcers and predictive factors for amputation

Diabetes mellitus is a common metabolic disorder. Among various complications, diabetic neuropathy and peripheral vascular disorders are closely associated with diabetic foot ulcers (DFUs). Lower extremity ulcers and amputations are ongoing problems among individuals with diabetes. There are several classification systems for DFUs; however, no prognostic system has to date been accepted as the gold standard or the optimum prediction tool for amputations. A retrospective study was designed. Demographic data and baseline laboratory data were gathered and scored or evaluated using five representative DFU classification systems. These included (i) the diabetic ulcer severity score (DUSS); (ii) University of Texas (UT) diabetic wound classification; (iii) Meggitt-Wagner classification; (iv) depth of the ulcer, extent of bacterial colonisation, phase of ulcer and association aetiology (DEPA) scoring system; and (v) site, ischaemia, neuropathy, bacterial infection and depth (SINBAD) score. Finally, a statistical analysis was performed. A total of 137 patients were included in this study. During the follow-up, DFU had healed in 51·1% of subjects and 48·9% of the individuals underwent lower extremity amputations (LEAs). In a univariable logistic regression analysis, history of previous DFU, hypertension, neuropathy, haemoglobin, C-reactive protein (CRP) and ankle-brachial index (ABI) showed a statistically significant difference between the healed group and the LEA group. Moreover, the stages, grades or overall prognostic ability of all five classifications were highly associated with the overall occurrence of LEA. On multivariable logistic regression analysis of the risk of LEA, all classifications showed a significant positive trend with an increased number of amputations. All the five classification systems exhibited high sensitivity, specificity, classification accuracy, positive predictive, negative predictive and area under the curve (AUC) values. They showed substantial accuracy and their main variables were associated with LEA occurrence. The Wagner and UT systems, although they are relatively simple to assess, were better predictors of LEA.

A Predictive Model for Diabetic Foot Ulcer Outcome: The Wound Healing Index

Objective: To develop a healing index for patients with diabetic foot ulcers (DFUs) for use in clinical practice, research analysis, and clinical trials.

Approach: U.S. Wound Registry data were examined retrospectively and assigned a clear outcome (healed, amputated, etc.). Significant variables were identified with bivariate analyses. A multivariable logistic regression model was created based on significant factors (p < 0.05) and tested on a hold-out sample of data. Out of 13,266 DFUs from the original dataset, 6,440 were eligible for analysis. The logistic regression model included 5,239 ulcers, of which 3,462 healed (66.1%). The 10% validation sample utilized 555 ulcers, of which 377 healed (67.9%).

Results: Variables that significantly predicted healing were as follows: wound age (duration in days), wound size, number of concurrent wounds of any etiology, evidence of bioburden/infection, patient age, Wagner grade, being nonambulatory, renal dialysis, renal transplant, peripheral vascular disease, and patient hospitalization for any reason.

Innovation: We present a validated stratification system, previously described as the Wound Healing Index (WHI), which predicts healing likelihood of patients with DFUs, incorporating patient- and wound-specific variables.

Conclusion: The DFU WHI is a comprehensive and user-friendly validated predictive model for DFU healing. It can risk stratify patients enrolled in clinical research trials, stratify patient data for quality reporting and benchmarking activities, and identify patients most likely to require costly therapy to heal.

Color-coded etiological keys: A simple survey tool towards amputation-free limb survival in diabetic foot lesions

Aims/Introduction

We devised a simple implementable color‐coded etiological key survey based on six significant categories to screen and manage all diabetic foot patients. The study results were analyzed to verify the impact of this survey.

Materials and Methods

First we carried out a retrospective internal survey of all diabetic patients that presented to us during the period from January 2004 to January 2007. We used this analysis to develop the color‐coded etiological survey, and applied it to analyze patients prospectively for 5 years from May 2007 to May 2012. Out of 4,102 diabetic foot patients, 739 patients were referred by other medical facilities for major amputation as a result of the severity of their foot lesions. This group was then subjected to further analysis to study the value and impact of the survey on amputation‐free limb survival.

Results

Blood quality abnormalities were most prevalent followed by peripheral occlusive diseases, whereas tissue loss was the least. After the completion of the assessment process, management was implemented according to the defined protocol based on the lesions’ characteristics. The primary end‐point of major amputation‐free limb survival was achieved in 72.5% of patients, with an average hospital stay of 13.3 days. Statistical analysis of the etiological keys showed a significant impact of tissue loss, and previous foot surgery as a poor predictor of limb loss.

Conclusion

We conclude that the implementation of the color‐coded etiological key survey can provide efficient and effective service to diabetic foot victims with comparable outcomes to dedicated diabetic foot clinics.

Treatment of complicated skin and skin structure infections in areas with low incidence of antibiotic resistance-a retrospective population based study from Finland and Sweden

Complicated skin and skin-structure infections (cSSSI) are a common reason for hospitalization and practically all new antimicrobial agents against Gram-positive bacteria are studied in cSSSI. The aim of this population-based observational study was to assess the treatment of patients with cSSSI in areas with a low incidence of antibiotic resistance. The study population consisted of adult residents who were treated because of cSSSI during 2008-2011 from two Nordic cities, Helsinki and Gothenburg. In the final analysis population (460 patients; mean age 60.8 years; 60.9% male) 13.3% of patients had bacteraemia, 15.9% were admitted to an Intensive Care Unit and 51.5% underwent at least one surgical intervention. Treatment failure occurred in 28.2%, initial antibiotic treatment modification to another intravenous drug in 38.5% and streamlining in 5.0% of the cases. Gram-positive bacteria were predominantly isolated, with staphylococci (24.5%) and streptococci (16.0%) being the most common aetiologies. Median overall durations of hospital stay and antimicrobial treatment were 13 and 17 days, respectively, and on average 3.5 (SD 2.1) different antibiotics were used per patient. Oral antimicrobial treatment was continued in 64.3% of patients after discharge. The overall mortality rates in 30 days and in 12 months were 4.1% and 11.8%, respectively, and 16.4% of patients had a recurrence of SSSI within 12 months. In conclusion, in this population-based study antimicrobial treatment modifications were frequent and the treatment time was longer than recommended. However, bacteraemia, clinical failure and recurrences were more common than in previous non-population-based studies.

Predictors for limb loss among patient with diabetic foot infections: an observational retrospective multicentric study in Turkey

We aimed to investigate the predictors for limb loss among patients with diabetes who have complicated skin/soft-tissue infections. In this observational study, consecutive patients with diabetic foot infection (DFI) from 17 centres in Turkey, between May 2011 and May 2013 were included. The Turkish DFI Working Group performed the study. Predictors of limb loss were investigated by multivariate analysis. In total, 455 patients with DFI were included. Median age was 61 years, 68% were male, 65% of the patients were hospitalized, 52% of the patients had used antibiotics within the last month, and 121 (27%) had osteomyelitis. Of the 208 microorganisms isolated, 92 (44.2%) were Gram-positive cocci and 114 (54.8%) were Gram-negative rods (GNR). The most common GNR was Pseudomonas; the second was Escherichia coli, with extended spectrum β-lactamase positivity of 33%. Methicillin-resistant Staphylococcus species were found in 14% (29/208). Amputations were performed in 126/455 (28%) patients, 44/126 (34%) of these were major amputations. In multivariate analysis, significant predictors for limb loss were, male gender (OR 1.75, 95% CI 1.04-2.96, p 0.034), duration of diabetes >20 years (OR 1.9, 95% CI 1.18-3.11, p 0.008), infected ulcer versus cellulitis (OR 1.9, 95% CI 1.11-3.18, p 0.019), history of peripheral vascular disease (OR 2, 95% CI 1.26-3.27, p 0.004), retinopathy (OR 2.25, 95% CI 1.19-4.25, p 0.012), erythrocyte sedimentation rate >70 mm/hr (OR 1.6, 95% CI 1.01-2.68, p 0.05), and infection with GNR (OR 1.8, 95% CI 1.08-3.02, p 0.02). Multivariate analysis revealed that, besides the known risk factors such as male gender, duration of diabetes >20 years, infected ulcers, history of peripheral vascular disease and retinopathy, detection of GNR was a significant predictor of limb loss.

The role of anaerobes in diabetic foot infections

Diabetic foot infections (DFI) are a common cause of morbidity and, on occasion, even mortality. Infection can be either mono- or polymicrobial, with a wide variety of potential pathogens. Anaerobes may be involved, particularly in wounds that are deeper or more chronic, and are more frequently identified when using modern molecular techniques, such as 16s PCR and pyrosequencing. It remains unclear whether the presence of anaerobes in DFI leads to more severe manifestations, or if these organisms are largely colonizers associated with the presence of greater degrees of tissue ischemia and necrosis. Commonly used empiric antibiotic therapy for diabetic foot infections is generally broad-spectrum and usually has activity against the most frequently identified anaerobes, such as Peptostreptococcus and Bacteroides species. Adequate surgical debridement and, when needed, foot revascularization may be at least as important as the choice of antibiotic to achieve a successful treatment outcome.

The major predictors of amputation and length of stay in diabetic patients with acute foot ulceration

BACKGROUND

Diabetic foot infections are associated with substantial morbidity and mortality. Prediction of diabetic foot ulcer outcome may be helpful for optimizing management strategy. This study aimed to determine the major predictors of amputation and length of stay in diabetic patients with acute foot ulceration.

METHODS

A total of 55 type 2 diabetic patients with diabetic foot infection were enrolled. The patients were evaluated according to the Infectious Diseases Society of America and International Working Group on the Diabetic Foot criteria and also the Wagner's classification. Blood samples were taken at the start of hospitalization for the measurement of glucose, hemoglobin A1C (HbA1C), white blood cells (WBC), C-reactive protein (CRP), and erythrocyte sedimentation rate (ESR). Length of stay in hospital was recorded.

RESULTS

WBC and CRP were significantly higher in lower-extremity amputation (LEA) group (p = 0.001 and p = 0.008, respectively); also, ESR was higher in this group, but there was no statistical significance. Wagner grade and infection severity were significantly higher in the LEA group as compared with the non-LEA group (both p values < 0.001). Glycemic control parameters (i.e., HbA1C, plasma glucose) were not different in LEA and non-LEA groups. In correlation analyses, amputation rate was negatively correlated (r = - 0.512, p < 0.001) with length of stay. WBC, ESR, CRP, Wagner grade, and severity of infection showed positive correlation with length of stay (r = 0.493, p < 0.001; r = 0.271, p = 0.045; r = 0.299, p = 0.027; r = 0.434, p = 0.001; and r = 0.464, p < 0.001, respectively).

CONCLUSIONS

Baseline levels of acute-phase reactants, especially CRP, WBC, ESR, and increased Wagner grade, appeared to be helpful in predicting amputation and length of stay in diabetic patients with acute foot ulceration. However, duration of diabetes and glucose control seems to have no effect.

Treatment of the diabetic foot - to amputate or not?

Background

Diabetic foot infections are a frequent clinical problem. About 50% of patients with diabetic foot infections who have foot amputations die within five years. Properly managed most can be cured, but many patients needlessly undergo amputations because of improper diagnostic and therapeutic approaches.

Discussion

The article debates the pros and cons of amputation of the diabetic foot. The thesis is that if the guidelines on the management of the diabetic foot are followed primary amputation is only necessary for the unsalvageable diabetic foot. This approach would reduce the incidence of lower limb amputations in diabetic patients.

Summary

We favour the argument that a structured clinical and vascular assessment would help clinical decision- making as to which patients to hospitalize, which to send for imaging, or for whom to recommend surgical interventions. Endovascular procedures are the future in the treatment of diabetic arterial disease and hence the diabetic foot.

Correlation of adherence to the 2012 Infectious Diseases Society of America practice guidelines with patient outcomes in the treatment of diabetic foot infections in an outpatient parenteral antimicrobial programme

AIM

To evaluate adherence to the 2012 Infectious Diseases Society of America practice guidelines for the management of patients with diabetic foot infections and to determine an association between adherence and clinical outcome.

METHODS

A retrospective chart review was performed to evaluate the management and clinical outcomes of patients with diabetic foot infections treated with outpatient parenteral antimicrobial therapy between 1 January 2011 and 30 June 2012 at Wishard Health Services/Eskenazi Health. Adherence to individual Infectious Diseases Society of America diabetic foot infection treatment guideline recommendations was measured, and then assessed in relation to clinical outcome.

RESULTS

A total of 57 patients (61% male, mean age 54 years) with moderate to severe diabetic foot infection met the inclusion criteria. None of the treatment courses of these patients adhered to all the Infectious Diseases Society of America guideline recommendations. The recommendations most frequently adhered to were consultation of appropriate multidisciplinary teams (n=54, 94.7%) and performance of diagnostic imaging (n=52, 89.5%). The recommendations least frequently adhered to were diabetic foot wound classification scoring on admission (n=0, 0%), appropriate culture acquisition (n=12, 21.2%), surgical intervention when indicated (n=32, 46.2%) and appropriate empiric antibiotic selection (n=34, 59.7%). Of 56 patients, 52 (92.9%) experienced clinical cure at the end of outpatient parenteral antimicrobial therapy compared with 34 of 53 patients (64%) at 6 months after the completion of therapy. Adherence to individual guidelines was not associated with clinical outcome. Patients who experienced treatment failure were more likely to have severe diabetic foot infection or peripheral neuropathy.

CONCLUSIONS

Adherence to the Infectious Diseases Society of America diabetic foot infection guideline recommendations was found to be suboptimal in the present study. The effect of adhering to individual Infectious Diseases Society of America diabetic foot infection recommendations on clinical outcome needs to be investigated.

SIRS is valid in discriminating between severe and moderate diabetic foot infections

OBJECTIVE

This retrospective, single-center study was designed to distinguish severe diabetic foot infection (DFI) from moderate DFI based on the presence or absence of systemic inflammatory response syndrome (SIRS).

RESEARCH DESIGN AND METHODS

The database of a single academic foot and ankle program was reviewed and 119 patients were identified. Severe DFI was defined as local infection associated with manifestation of two or more objective findings of systemic toxicity using SIRS criteria.

RESULTS

Patients with severe DFI experienced a 2.55-fold higher risk of any amputation (95% CI 1.21-5.36) and a 7.12-fold higher risk of major amputation (1.83-41.05) than patients with moderate DFI. The risk of minor amputations was not significantly different between the two groups (odds ratio 1.02 [95% CI 0.51-2.28]). The odds of having a severe DFI was 7.82 times higher in patients who presented with gangrene (2.03-44.81) and five times higher in patients who reported symptoms of anorexia, chills, nausea, or vomiting (2.22-11.25). The mean hospital length of stay for patients with severe DFI was ∼4 days longer than for patients with moderate DFI, and this difference was statistically significant.

CONCLUSIONS

SIRS is valid in distinguishing severe from moderate DFI in hospitalized patients. Patients with severe DFI, as by manifesting two or more signs of systemic inflammation or toxicity, had higher rates of major amputation and longer hospital stays and required more surgery and more subsequent admissions than patients who did not manifest SIRS.

Risk factors for recurrence of diabetic foot ulcers: prospective follow-up analysis in the Eurodiale subgroup

Few studies have examined factors associated with diabetic foot ulcer (DFU) recurrence. Using data from patients enrolled in the prospective Eurodiale DFU study, we investigated the frequency of and risk factors for DFU recurrence after healing during a 3-year follow-up period. At our site, 93 Eurodiale-enrolled patients had a healed DFU. Among these, 14 were not alive; of the remaining 79 patients we enrolled 73 in this study. On entry to the Eurodiale study, we assessed demographic factors (age, sex and distance from hospital); diabetes-related factors [duration, and glycated haemoglobin (HbA1c) levels]; comorbidities (obesity, renal failure, smoking and alcohol abuse) and DFU-related factors [peripheral arterial disease, ulcer infection, C-reactive protein (CRP) and; foot deformities]. During the 3-year follow-up period, a DFU had recurred in 42 patients (57.5%). By stepwise logistic regression of findings at initial DFU presentation, the significant independent predictors for recurrence were plantar ulcer location [odds ratio (OR) 8.62, 95% confidence interval (CI) 2.2-33.2]; presence of osteomyelitis (OR 5.17, 95% CI 1.4-18.7); HbA1c > 7.5% ([DCCT], OR 4.07, 95% CI 1.1-15.6) and CRP > 5 mg/l (OR 4.27, 95% CI 1.2-15.7). In these patients with a healed DFU, the majority had a recurrence of DFU during a 3-year follow-up period, despite intensive foot care. The findings at diagnosis of the initial DFU were independent risk factors associated with ulcer recurrence (plantar location, bone infection, poor diabetes control and elevated CRP) and define those at high risk for recurrence, but may be amenable to targeted interventions.

Inpatient management of diabetic foot disorders: a clinical guide

The implementation of an inpatient diabetic foot service should be the goal of all institutions that care for patients with diabetes. The objectives of this team are to prevent problems in patients while hospitalized, provide curative measures for patients admitted with diabetic foot disorders, and optimize the transition from inpatient to outpatient care. Essential skills that are required for an inpatient team include the ability to stage a foot wound, assess for peripheral vascular disease, neuropathy, wound infection, and the need for debridement; appropriately culture a wound and select antibiotic therapy; provide, directly or indirectly, for optimal metabolic control; and implement effective discharge planning to prevent a recurrence. Diabetic foot ulcers may be present in patients who are admitted for nonfoot problems, and these ulcers should be evaluated by the diabetic foot team during the hospitalization. Pathways should be in place for urgent or emergent treatment of diabetic foot infections and neuropathic fractures/dislocations. Surgeons involved with these patients should have knowledge and interest in limb preservation techniques. Prevention of iatrogenic foot complications, such as pressure sores of the heel, should be a priority in patients with diabetes who are admitted for any reason: all hospitalized diabetic patients require a clinical foot exam on admission to identify risk factors such as loss of sensation or ischemia. Appropriate posthospitalization monitoring to reduce the risk of reulceration and infection should be available, which should include optimal glycemic control and correction of any fluid and electrolyte disturbances.

Severity of diabetic foot infection and rate of limb salvage

BACKGROUND

Foot infections are limb-threatening complications in patients with diabetes mellitus (DM), and proper classification of the severity of diabetic foot infection (DFI) is important in determining an effective antibiotic regimen, the need for hospitalization and surgery, and the risk of amputation. Our hypothesis was that patients with severe DFI would have a longer hospitalization than those with moderate DFI. The purposed of this study was 2-fold. The first purpose was to define DFI using readily available clinical information and objective parameters outlined by consensus statements. The second purpose of this study was to assess rates of amputation and limb salvage for hospitalized patients with DFI.

METHODS

The database of a single academic foot and ankle program was reviewed for patients who were hospitalized for a DFI from 2006 to 2011. Inpatient and outpatient electronic medical records identified 100 patients. Severe DFI was defined as having 2 or more objective findings of systemic toxicity and/or metabolic instability at the time of initial assessment.

RESULTS

The length of stay was significantly shorter for patients with a moderate infection than for those with a severe infection (median 5 days vs 8 days, P = .021). A nonsignificant trend was observed that indicated higher rates of limb salvage in patients with moderate infections compared with patients with severe infections (94% vs 80%, P = .081).

CONCLUSION

Patients with severe DFI had a median hospital stay that was 60% longer than that of patients with moderate DFI. In this sample, 55% of patients with a severe DFI required some type of amputation compared with 42% of patients with a moderate DFI.

LEVEL OF EVIDENCE

Level III, retrospective control cohort study.

Monitoring of systemic inflammatory response in diabetic patients with deep foot infection treated with negative pressure wound therapy

BACKGROUND

The purpose of this study was to establish the safety of negative pressure wound therapy (NPWT) in the treatment of acutely debrided, deep diabetic foot infections (DDFI) and to determine the value of inflammatory markers in monitoring of treatment of these infections with negative pressure wound therapy.

METHODS

A group of ten patients with DDFI treated by radical surgical debridement and simultaneous NPWT was prospectively studied. During the debridement, a deep tissue sample was obtained and sent for microbiological testing. The patients were followed clinically for 10 days and NPWT dressings were changed every 2 to 3 days or sooner when indicated. The peripheral blood samples were obtained before the radical debridement and 3 and 10 days afterwards and concentrations of white blood cell, neutrophils, lymphocytes and C-reactive protein (CRP) were measured. The changes in concentration of inflammatory markers were analyzed with a Friedman test.

RESULTS

In all but one patient the presence of DDFI was confirmed by the culture results. At baseline, the elevated WBC and neutrophil concentrations were observed only in half of the patients while the CRP concentration was elevated in nine patients. During followup, all patients showed a favorable clinical evolution and statistically significant decrease of WBC, neutrophils and CRP (p<0.001). There were not statistically significant changes in lymphocyte count.

CONCLUSION

NPWT can be safely applied in acutely debrided DDFI. CRP seems to be the most adequate parameter for both diagnosis and monitoring of treatment of DDFI.

2012 Infectious Diseases Society of America clinical practice guideline for the diagnosis and treatment of diabetic foot infections

Foot infections are a common and serious problem in persons with diabetes. Diabetic foot infections (DFIs) typically begin in a wound, most often a neuropathic ulceration. While all wounds are colonized with microorganisms, the presence of infection is defined by ≥2 classic findings of inflammation or purulence. Infections are then classified into mild (superficial and limited in size and depth), moderate (deeper or more extensive), or severe (accompanied by systemic signs or metabolic perturbations). This classification system, along with a vascular assessment, helps determine which patients should be hospitalized, which may require special imaging procedures or surgical interventions, and which will require amputation. Most DFIs are polymicrobial, with aerobic gram-positive cocci (GPC), and especially staphylococci, the most common causative organisms. Aerobic gram-negative bacilli are frequently copathogens in infections that are chronic or follow antibiotic treatment, and obligate anaerobes may be copathogens in ischemic or necrotic wounds. Wounds without evidence of soft tissue or bone infection do not require antibiotic therapy. For infected wounds, obtain a post-debridement specimen (preferably of tissue) for aerobic and anaerobic culture. Empiric antibiotic therapy can be narrowly targeted at GPC in many acutely infected patients, but those at risk for infection with antibiotic-resistant organisms or with chronic, previously treated, or severe infections usually require broader spectrum regimens. Imaging is helpful in most DFIs; plain radiographs may be sufficient, but magnetic resonance imaging is far more sensitive and specific. Osteomyelitis occurs in many diabetic patients with a foot wound and can be difficult to diagnose (optimally defined by bone culture and histology) and treat (often requiring surgical debridement or resection, and/or prolonged antibiotic therapy). Most DFIs require some surgical intervention, ranging from minor (debridement) to major (resection, amputation). Wounds must also be properly dressed and off-loaded of pressure, and patients need regular follow-up. An ischemic foot may require revascularization, and some nonresponding patients may benefit from selected adjunctive measures. Employing multidisciplinary foot teams improves outcomes. Clinicians and healthcare organizations should attempt to monitor, and thereby improve, their outcomes and processes in caring for DFIs.

Diabetic foot infections: current concept review

The purpose of this manuscript is to provide a current concept review on the diagnosis and management of diabetic foot infections which are among the most serious and frequent complications encountered in patients with diabetes mellitus. A literature review on diabetic foot infections with emphasis on pathophysiology, identifiable risk factors, evaluation including physical examination, laboratory values, treatment strategies and assessing the severity of infection has been performed in detail. Diabetic foot infections are associated with high morbidity and risk factors for failure of treatment and classification systems are also described. Most diabetic foot infections begin with a wound and once an infection occurs, the risk of hospitalization and amputation increases dramatically. Early identification of infection and prompt treatment may optimize the patient's outcome and provide limb salvage.

A prospective, multi-center study: factors related to the management of diabetic foot infections

The Turkish Association of Clinical Microbiology and Infectious Diseases, Diabetic Foot Infections Working Group conducted a prospective study to determine the factors affecting the outcomes of diabetic foot infections. A total of 96 patients were enrolled in the study. Microbiological assessment was performed in 86 patients. A total of 115 causative bacteria were isolated from 71 patients. The most frequently isolated bacterial species was Pseudomonas aeruginosa (n = 21, 18.3%). Among cases with bacterial growth, 37 patients (43%) were infected with 38 (33%) antibiotic-resistant bacteria. The mean (±SD) antibiotics cost was 2,220.42 (±994.59) USD in cases infected with resistant bacteria, while it was 1,206.60 (±1,160.6) USD in patients infected with susceptible bacteria (p < 0.001). According to the logistic regression analysis, the risk factors related to the growth of resistant bacteria were previous amputation (p = 0.018, OR = 7.229) and antibiotics administration within the last 30 days (p = 0.032, OR = 3.796); that related to the development of osteomyelitis was wound size >4.5 cm(2) (p = 0.041, OR = 2.8); and that related to the failure of the treatment was the growth of resistant bacteria (p = 0.016, OR = 5.333). Diabetic foot osteomyelitis is usually a chronic infection and requires surgical therapy. Amputation is the accepted form of treatment for osteomyelitis. Limited limb-saving surgery and prolonged antibiotic therapy directed toward the definitive causative bacteria are most appropriate. This may decrease limb loss through amputations. As a result the infections caused by resistant bacteria may lead to a high cost of antibiotherapy, prolonged hospitalization duration, and failure of the treatment.

Extended leg infection of diabetic foot ulcers: risk factors and outcome

OBJECTIVE

To identify the risk factors for extension of infection to the leg in diabetic foot ulcers (DFU) and to evaluate its role as a prognostic measure regarding limb salvage and healing time.

METHOD

This retrospective case-control study took place in Jabir Abu Eliz Diabetic (JADC) during 2006-2008. Forty-eight patients diagnosed with a diabetic foot ulcer (DFU) with the infection extending to the leg (case group) were compared with an equal number of patients with a DFU without extension (control group). Risk factors for extension were identified by univariate analysis and both groups were compared with regard to limb salvage and healing time.

RESULTS

Previous history of toe amputation was more frequent in the case group (p=0.004). The case group patients were significantly more likely to present with fever (p=0.01), pallor (p=0.02), confusion (p=0.04), and necrosis (p=0.004). Ulcers located in the heel were more frequent in the case group when compared with controls (p=0.0001) while more toes ulcers were found in the control group (p=0.001). A significant number of patients in the case group had an ulcer of more than 5cm diameter compared with those in the control group (p=0.001). The total number of patients presented with severe disease (Wagner grade 3-5) was significantly more in the case group compared with controls (p=0.004). Patients with severe infection (grade 4) were more in the case group compared with the controls (p=0.04). There were no significant differences between the two groups with regard to major and minor amputation rate. The case group had a longer duration of healing when compared with the controls. Seventy-five per cent of the controls healed by 6 months (n=31) compared with 22% in the case group (n=8 ; p=0.001).

CONCLUSION

Toe amputation, wound located in the heel, wound size more than 5cm and advanced Wagner grade (3-5) and severe sepsis, grade 4, may be considered as risk factors for extension of infection to the leg in DFU. However, this extension did not carry a poor prognostic value to the final outcome if adequate therapeutic measures were followed.

Surgical treatment of limb- and life-threatening infections in the feet of patients with diabetes and at least one palpable pedal pulse: successes and lessons learnt

Outcomes of surgically treated limb- and life-threatening infections in patients with diabetes and a well-vascularized foot based only on the palpation of foot pulses are not well known. The authors retrospectively studied a series of 173 patients with diabetes and limb- (moderate) or life- (severe) threatening infections with at least one palpable pedal pulse who were admitted to their department for the treatment of infected diabetic foot from January 1, 1998, to December 31, 2009. A total of 141 patients (81.5%) presented with limb-threatening/moderate infections and 32 (18.5%) with life-threatening/severe infections. In all, 49 patients (28.3%) presented with soft tissue infections only, 90 (52%) with osteomyelitis and 34 (19.7%) with a combined infection. Amputation was needed in 74 patients (42.7%), of whom 6 needed a major amputation (3.5% of overall). A total of 99 (57.2%) patients were treated by conservative surgery. Four patients (2.3%) died during the postoperative period (30 days). Limb salvage was achieved in 167 (96.5%) of the patients who were followed up until healing. Healing of the wounds by secondary intention was achieved in a median of 72 days. Clinical results permit the observation that a high rate of limb salvage can be achieved after the surgical treatment of limb- and life-threatening infections in patients with at least one palpable pedal pulse.

Acute phase reactants predict the risk of amputation in diabetic foot infection

BACKGROUND

prediction of amputation would aid clinicians in the management of diabetic foot infections. We aimed to assess the predictive value of baseline and post-treatment levels of acute phase reactants in the outcome of patients with diabetic foot infections.

METHODS

we collected data prospectively during minimum follow-up of 6 months in patients with infected diabetic foot ulcers hospitalized in Dokuz Eylul University Hospital between January 1, 2003, and January 1, 2008. After excluding patients who did not attend the hospital for follow-up visits regularly (n = 36), we analyzed data from 165 foot ulcer episodes.

RESULTS

limb ischemia and osteomyelitis were much more frequent in patients who underwent amputation. Wagner grade, which assesses ulcer depth and the presence of osteomyelitis or gangrene, was higher in patients who needed amputation. Ulcer size was slightly larger in the amputation group. Baseline and post-treatment C-reactive protein levels, erythrocyte sedimentation rates, white blood cell counts, and platelet counts were significantly elevated in patients who underwent amputation. Albumin levels were significantly suppressed in the amputation group. Univariate analysis showed that a 1-SD increase in baseline and post-treatment C-reactive protein levels, erythrocyte sedimentation rates, and white blood cell counts and a 1-SD decrease in post-treatment albumin levels were significantly associated with increased risk of amputation. Post-treatment C-reactive protein level was strongly associated with amputation risk.

CONCLUSIONS

circulating levels of acute phase reactants were associated with amputation risk in diabetic foot infections.

Post-treatment leukocytosis predicts an unfavorable clinical response in patients with moderate to severe diabetic foot infections

Our aim was to determine whether post-treatment laboratory values could help to predict the clinical response in patients with advanced diabetic foot infections. One hundred and three consecutive patients hospitalized for moderate or severe diabetic foot infections at a large, university-affiliated hospital were identified and their records retrospectively reviewed. Definitive therapy during each patient's hospital course was defined as any foot surgery when additional major surgery was not anticipated or when a course of deep soft tissue and/or bone culture-specific antibiotics had been initiated. The clinical response was assessed at 90 days after the start of definitive therapy. A poor response was recognized as persistent infection at the initial or a contiguous site or when unplanned revision surgery or amputation was subsequently required. The peripheral white blood cell count, neutrophil count, erythrocyte sedimentation rate, and C-reactive protein levels measured shortly after initiating definitive therapy (i.e., post-treatment) were examined for their association with the clinical response using logistic regression models. A total of 38 patients with the complete compliment of laboratory and clinical follow-up aged 59.7 ± 12.3 years with a diabetes duration of 13.3 ± 9.1 years were included. Leukocytosis, defined as a white blood cell count >11,000 cells/μL, observed an average of 3 ± 1.4 days after treatment, was the single most important marker for predicting a poor clinical response, and the only significant study variable in both univariate and multivariate analyses (multivariate odds ratio 9.7, 95% confidence interval 1.0 to 92, p = .048). We conclude that leukocytosis observed shortly after initiating definitive therapy is predictive of an unfavorable clinical response by 90 days.

A classification of diabetic foot infections using ICD-9-CM codes: application to a large computerized medical database

Background

Diabetic foot infections are common, serious, and varied. Diagnostic and treatment strategies are correspondingly diverse. It is unclear how patients are managed in actual practice and how outcomes might be improved. Clarification will require study of large numbers of patients, such as are available in medical databases. We have developed and evaluated a system for identifying and classifying diabetic foot infections that can be used for this purpose.

Methods

We used the (VA) Diabetes Epidemiology Cohorts (DEpiC) database to conduct a retrospective observational study of patients with diabetic foot infections. DEpiC contains computerized VA and Medicare patient-level data for patients with diabetes since 1998. We determined which ICD-9-CM codes served to identify patients with different types of diabetic foot infections and ranked them in declining order of severity: Gangrene, Osteomyelitis, Ulcer, Foot cellulitis/abscess, Toe cellulitis/abscess, Paronychia. We evaluated our classification by examining its relationship to patient characteristics, diagnostic procedures, treatments given, and medical outcomes.

Results

There were 61,007 patients with foot infections, of which 42,063 were classifiable into one of our predefined groups. The different types of infection were related to expected patient characteristics, diagnostic procedures, treatments, and outcomes. Our severity ranking showed a monotonic relationship to hospital length of stay, amputation rate, transition to long-term care, and mortality.

Conclusions

We have developed a classification system for patients with diabetic foot infections that is expressly designed for use with large, computerized, ICD-9-CM coded administrative medical databases. It provides a framework that can be used to conduct observational studies of large numbers of patients in order to examine treatment variation and patient outcomes, including the effect of new management strategies, implementation of practice guidelines, and quality improvement initiatives.

Diabetes foot ulceration in a Nigerian hospital: in-hospital mortality in relation to the presenting demographic, clinical and laboratory features

This prospective study assessed in-hospital mortality from diabetic foot ulcer in relation to the demographic, clinical and laboratory features at presentation. Forty-two patients admitted with diabetic foot ulcer were followed up from admission till discharge from hospital. Those who survived or died were compared for any differences in demographic, clinical and laboratory parameters at presentation. The mean age and duration of diabetes for the 42 patients were 56.1 +/- 1.9 years and 8.3 +/- 1.1 years, respectively. The in-hospital mortality rate amongst the 42 subjects was 40.5%. Ulcer grade > or =4, leucocytosis and anaemia were more prevalent in those who demised in comparison with survivors.

The treatment of diabetic foot infections: focus on ertapenem

Clinically, 3 distinct stages of diabetic foot infection may be recognized: localized infection, spreading infection and severe infection. Each of these presentations may be complicated by osteomyelitis. Infection can be caused by Gram-positive aerobic, and Gram-negative aerobic and anaerobic bacteria, singly or in combination. The underlying principles are to diagnose infection, culture the bacteria responsible and treat aggressively with antibiotic therapy. Localized infections with limited cellulitis can generally be treated with oral antibiotics on an outpatient basis. Spreading infection should be treated with systemic antibiotics. Severe deep infections need urgent admission to hospital for wide-spectrum intravenous antibiotics. Clinical and microbiological response rates have been similar in trials of various antibiotics and no single agent or combination has emerged as most effective. Recently, clinical and microbiological outcomes for patients treated with ertapenem were equivalent to those for patients treated with piperacillin/tazobactam. It is also important to judge the need for debridement and surgery, to assess the arterial supply to the foot and consider revascularization either by angioplasty or bypass if the foot is ischemic. It is also important to achieve metabolic control. Thus infection in the diabetic foot needs full multidisciplinary treatment.

Foot infections in diabetes (DFIs) in the out-patient setting: an Italian multicentre observational survey

AIMS

To conduct a multicentre observational study to describe management of foot infections in diabetes in the out-patient setting in Italy.

PATIENTS AND METHODS

Ten centres equally distributed nationwide were asked to collect, by means of a spreadsheet (Access/Excel Microsoft program), data concerning 30 consecutive diabetic patients with foot infections deemed suitable for antibiotic treatment in the out-patient setting. Centres with > or = 5 years' experience of out-patient management were selected. Data from 271 consecutive patients treated as out-patients were collected and analysed by the central coordinator. Statistical analysis was performed using the SPSS statistical software package.

RESULTS

Lesions were mainly located at the toes and midfoot (33.6 and 30.2%, respectively); 63 (23.2%) patients had multiple ulcers. Seventy (25.8%) patients also had concomitant osteomyelitis. Three hundred and four pathogens, including Gram-positive and Gram-negative aerobes and anaerobes, were isolated in 219/271 patients (80.8%) by culturing debrided tissue (71.2%) or purulent material (28.8%). Infections were polymicrobial in 33.8% of patients. The most common pathogens were Staphylococcus aureus (27.3%) and Pseudomonas spp. (20.4%); enterobacteriaceae, enterococci, streptococci and anaerobes accounted for 11.5, 7.6, 6.9 and 1.9%, respectively. Antibiotics were frequently administered by parenteral route and frequently in combination. Piperacillin/tazobactam was the parenteral antibiotic most frequently utilized (21.1%). Cure/improvement was observed in 93.4% of patients.

CONCLUSIONS

Foot ulcers in diabetes are common and serious; the aetiology is often polymicrobial, often including S. aureus and Pseudomonas spp. Treatment in the out-patient setting is safe and effective, and penicillins together with beta-lactamase inhibitors and fluoroquinolones are the most frequent choice.

New developments in diagnosing and treating diabetic foot infections

Foot infections are common in persons with diabetes and are often the proximate cause of lower extremity amputation. There have been many publications in the past few years dealing with the appropriate ways to diagnose and treat diabetic foot infections. This review presents information gathered from a comprehensive, ongoing surveillance of the literature (published and abstracts) over the past 4 years. Prospective studies have now defined the epidemiology of diabetic foot infections, as well as methods to score and classify the wounds. Several recently published guidelines can assist clinicians in managing these infections. The etiologic agents of infection have been well-defined, and the prevalence of multi-drug-resistance pathogens is growing. Molecular methods offer great promise for quicker and more sensitive diagnosis of infection. New antimicrobial agents, both systemic and topical, as well as novel local treatments, have been shown to be effective in various studies. Improved methods of deploying older agents have added to the variety of treatment approaches now available. Several adjunctive treatments may benefit some patients but their role is as yet unclear. While there is much yet to learn about the most cost-effective ways to diagnose and treat diabetic foot infections the main effort is now to disseminate the available information and facilitate employing the evidence-based guideline recommendations.

Novel antibiotics for the management of diabetic foot infections

Foot infections are a major cause of morbidity in diabetic patients. Staphylococcus aureus is the most important pathogen in mild infections; moderate to severe infections are frequently polymicrobial. Multidrug resistance is an increasing problem in isolates from diabetic feet. Worldwide, up to 30% of patients with diabetic foot infection (DFI) are colonised with methicillin-resistant S. aureus (MRSA), whilst extended-spectrum beta-lactamase-producing Gram-negative bacteria are also common in some countries. This emergence of drug resistance has coincided with the launch or imminent availability of many new antibiotics. Most of these were developed to target multidrug-resistant Gram-positive bacteria, although some have a spectrum of activity that includes Gram-negative bacteria and anaerobes. There is a variable amount of experience with these agents in treating skin and skin-structure infections (SSSIs), especially for DFI. However, at least some have a spectrum of activity and/or pharmacological properties that suggest that they may be of value in managing DFIs. The aim of this paper is to review evidence for the efficacy of new antibiotics in the management of SSSIs, including any data relating specifically to the diabetic foot, and to consider where they might fit into the therapeutic armory against DFI.