Surgical Diabetic Foot Infections: Is Osteomyelitis Associated With a Worse Prognosis?

It has been reported that patients with diabetes and foot ulcers complicated with osteomyelitis (OM) have a worse prognosis than those complicated with soft tissue infections (STI). Our study aimed to determine whether OM is associated with a worse prognosis in cases of moderate and severe diabetic foot infections requiring surgery. A retrospective series consisted of 150 patients who underwent surgery for diabetic foot infections. We studied the differences between OM versus STI. Furthermore, diabetic foot infections were reclassified into four groups: moderate STI (M-STI), moderate OM (M-OM), severe STI (S-STI), and severe OM (S-OM). The variables associated with prognosis were limb loss, length of hospital stay, duration of antibiotic treatment, recurrence of the infection, and time to healing (both the initial ulcer and the postoperative wound). No differences in limb salvage, hospital stay, duration of antibiotic treatment, recurrence of the infection, and time to healing were found when comparing OM with STI. Patients with M-O had a higher rate of recurrences after initial treatment and a longer time to healing when comparing with M-STI. We didn't find any differences between severe infections with or without OM. In conclusion, we have found in our surgical series of diabetic foot infections that OM is not associated with worse prognosis when comparing with STI regarding limb loss rate, length of hospital stays, duration of antibiotic treatment, recurrence of the infection, and time to healing. The results of the present series should further be confirmed by other authors.

The Role of Serial Radiographs in Diagnosing Diabetic Foot Bone Osteomyelitis

Background and Objective

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

Materials and Methods

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

Results

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

Conclusion

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

Long-term Mortality of a Cohort of Patients Undergoing Surgical Treatment for Diabetic Foot Infections. An 8-year Follow-up Study

We analyzed a retrospective cohort of 150 patients with diabetic foot infections (DFIs) who underwent surgical treatment to determine long-term outcomes. The median follow-up of the series was 7.6 years. Cox's proportional hazards model for survival time was performed and hazard ratios (HRs) were estimated. Survival times were plotted using the Kaplan-Meier method. Fifteen patients (10%) required readmission after discharge from the hospital for a recurrence of the infection. Ninety patients (60%) had re-ulcerations. Forty-nine (54.4% of those re-ulcerated) required new admission and 24 of them (26.6% of those re-ulcerated) finally required a new amputation. Overall cumulative survival rates at 1, 5, and 8 years were 95%, 78%, and 64%, respectively. Predictive variables of long-term mortality were insulin treatment (HR: 2.0, 95% CI: 1.1-3.6, P = .01), female sex (HR: 3.1, 95% CI: 1.7-5.3, P<.01) and estimated glomerular filtration rate (eGFR) <60 ml/min/1.73 m² (HR: 2.2, 95% CI: 1.1-4.2, P = .01). In conclusion, patients undergoing surgical treatment for DFIs had a high rate of recurrences and mortality. Women, patients who underwent treatment with insulin, and those with eGFR <60 ml/min/1.73 m² had a higher risk of long-term mortality.

Metatarsal Head Resections in Diabetic Foot Patients: A Systematic Review

A systematic review and proportional meta-analysis were carried out to investigate the complications that occur after surgical metatarsal head resection in diabetic foot patients. The PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) checklist recommendations were applied, and the selected studies were evaluated using a Strengthening the Reporting of Observational studies in Epidemiology (STROBE) checklist. PubMed (Medline) and Embase (Elsevier) were searched in December 2019 to find clinical trials, cohort studies, or case series assessing the efficacy of the metatarsal head resection technique in diabetic foot patients. The systematic review covered 21 studies that satisfied the inclusion criteria and included 483 subjects. The outcomes evaluated were the time to heal, recurrence, reulceration, amputation, and other complications. The proportion of recurrence was 7.2% [confidence interval (CI) 4.0–10.4, p < 0.001], that of reulceration was 20.7% (CI 11.6–29.8, p < 0.001), and that of amputation was 7.6% (CI 3.4–11.8, p < 0.001). A heterogeneity test indicated I² = 72.6% (p < 0.001) for recurrences, I² = 94% (p < 0.001) for reulcerations, and I² = 79% (p < 0.001) for amputations. We conclude that metatarsal head resections in diabetic foot patients are correlated with significant complications, especially reulceration.

Adjuvant antibiotic loaded bio composite in the management of diabetic foot osteomyelitis - A multicentre study

BACKGROUND

Diabetic foot ulcers are associated with a high morbidity and are common cause of non-traumatic lower limb amputations. The effect of debridement and the use of an adjuvant local antibiotic carrier in the treatment of diabetic foot ulcers with osteomyelitis was evaluated.

METHODS

A retrospective review of patients with diabetic foot ulceration and osteomyelitis treated by debridement with adjuvant local antibiotic was performed. Seventy patients with Texas Grade 3B & 3D lesions were included, with a mean age of 68 years. Cerament G, an antibiotic-loaded absorbable calcium sulphate/hydroxyapatite bio-composite was used along with intraoperative multiple bone sampling and culture-specific systemic antibiotics.

RESULTS

Patients were followed up until infection eradication or ulcer healing. Mean follow up was 10 months (4-28months). Nine patients had Charcot foot deformity, 14 had peripheral vascular disease. 62% of patients had forefoot, 5% midfoot and 33% hind foot involvement. Fifty-three patients (87%) had polymicrobial infection. Staphylococcus aureus was the most common microorganism isolated. Infection was eradicated in 63 patients (90%) with mean time to ulcer healing of 12 weeks. Seven patients were not cured and required further treatment. Five patients had below knee amputation.

CONCLUSIONS

Adjuvant, local antibiotic therapy with an absorbable bio-composite can help achieve up to 90% cure rates in diabetic foot ulceration with osteomyelitis. Cerament G can act as effective void filler allowing dead space management after excision and preventing reinfection and the need for multiple surgical procedures.

LEVEL OF EVIDENCE

Level IV- case series.

Pentraxin-3: A new parameter in predicting the severity of diabetic foot infection?

This study was undertaken to evaluate the diagnostic and prognostic values of pentraxin-3 (PTX-3) in patients with infected diabetic foot ulcers (IDFU) as well as to assess the association between PTX-3 levels and IDFU severity. This study included 60 IDFU patients (Group 1), 45 diabetic patients without DFU (Group 2), and 45 healthy controls. Patients with IDFU were divided into mild, moderate, and severe subgroups based on classification of clinical severity. Patients who underwent amputation were also documented. Blood samples were collected to determine PTX-3 levels. PTX-3 levels in healthy controls, Group 1, and Group 2 were 5.83 (3.41-20) ng/mL, 1.47 (0.61-15.13) ng/mL, and 3.26 (0.67-20) ng/mL, respectively. A negative correlation between plasma PTX-3 and glucose levels was found. There were significant differences in terms of procalcitonin (PCT) and PTX-3 levels in the subgroup analysis of Group 1. The PTX-3 level in patients who did or did not undergo amputation was 4.1 (0.8-13.7) and 1 (0.6-15.1) ng/mL, respectively. Results suggest that PTX-3 is a particularly effective marker in patients with IDFU, both in terms of predicting disease severity and assisting in the decision to perform amputation.

Optimal management of diabetic foot osteomyelitis: challenges and solutions

Purpose: Diabetic foot osteomyelitis (DFO) is the most frequent infection associated with diabetic foot ulcers, occurs in >20% of moderate infections and 50%-60% of severe infections, and is associated with high rates of amputation. DFO represents a challenge in both diagnosis and therapy, and many consequences of its condition are related to late diagnosis, delayed referral, or ill-indicated treatment. This review aimed to analyze the current evidence on DFO management and to discuss advantages and disadvantages of different treatment options. Methods: A narrative review of the evidence was begun by searching Medline and PubMed databases for studies using the keywords "management", "diabetic foot", "osteomyelitis", and "diabetic foot osteomyelitis" from 2008 to 2018. Results: We found a great variety of studies focusing on both medical and surgical therapies showing a similar rate of effectiveness and outcomes; however, the main factors in choosing one over the other seem to be associated with the presence of soft-tissue infection or ischemia and the clinical presentation of DFO. Conclusion: Further randomized controlled trials with large samples and long-term follow-up are necessary to demonstrate secondary outcomes, such as recurrence, recurrent ulceration, and reinfection associated with both medical and surgical options.

Current concepts for the evaluation and management of diabetic foot ulcers

The lifetime risk for diabetic patients to develop a diabetic foot ulcer (DFU) is 25%. In these patients, the risk of amputation is increased and the outcome deteriorates.More than 50% of non-traumatic lower-extremity amputations are related to DFU infections and 85% of all lower-extremity amputations in patients with diabetes are preceded by an ulcer; up to 70% of diabetic patients with a DFU-related amputation die within five years of their amputation.Optimal management of patients with DFUs must include clinical awareness, adequate blood glucose control, periodic foot inspection, custom therapeutic footwear, off-loading in high-risk patients, local wound care, diagnosis and control of osteomyelitis and ischaemia. Cite this article: EFORT Open Rev 2018;3:513-525. DOI: 10.1302/2058-5241.3.180010.

Diabetic Foot Infections: Update on Management

PURPOSE OF REVIEW

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

RECENT FINDINGS

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

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

AIMS

We aimed to evaluate the roles of interleukin-6 (IL-6), PCT, and fibrinogen levels in the differential diagnosis of the patients with infected diabetic foot ulcer (IDFU) and noninfected diabetic foot ulcer (NIDFU) and to compare those with C-reactive protein (CRP), white blood cell (WBC), and erythrocyte sedimentation rate (ESR).

METHODS

Patients over 18 years with a diagnosis of type 2 diabetes mellitus and DFU who were followed up in our hospital between 1 January 2016 and 1 January 2017 were included in the study. In addition to this patient group, patients with diabetes but without DFU were determined as the control group.

RESULTS

Thirty-eight patients with IDFU, 38 patients with NIDFU, and 43 patients as the control group were included in the study. Fifty-six point three percent of the patients who participated in the study were males, and the mean age was 61.07 ± 11.04 years. WBC, ESR, CRP, IL-6, and fibrinogen levels of the cases with IDFU were determined to be significantly higher compared to the cases in NIDFU (p < 0.01). The area under the ROC curve (AUROC) value was highest for CRP (0.998; p < 0.001), and the best cut-off value for CRP was 28 m/L. The best cut-off values for fibrinogen, IL-6, ESR, and WBC were 480 mg/dL, 105.8 pg/mL, 31 mm/h, and 11.6 (103 μ/L), respectively.

CONCLUSION

Serum PCT levels were not found to be effective in the discrimination of IDFU and NIDFU. Serum IL-6 and fibrinogen levels seem to be two promising inflammatory markers in the discrimination of IDFU.

Microbiology and Antimicrobial Therapy for Diabetic Foot Infections

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

Modern management of diabetic foot osteomyelitis. The when, how and why of conservative approaches

INTRODUCTION

Diabetic foot osteomyelitis (DFO) has long been considered a complex infection that is both difficult to diagnose and treat, and is associated with a high rate of relapse and limb loss. Areas covered: DFO can usually be diagnosed by a combination of clinical evaluation, serum inflammatory markers and plain X-ray. When the results of these procedures are negative or contradictory, advanced imaging tests or bone biopsy may be necessary. Staphylococcus aureus remains the most frequent microorganism isolated from bone specimens, but infection is often polymicrobial. Antibiotic therapy, preferably with oral agents guided by results of bone culture, for a duration of no more than six weeks, appears to be as safe and effective as surgery in cases of uncomplicated forefoot DFO. Surgery (which should be limb-sparing when possible) is always required for DFO accompanied by necrotizing fasciitis, deep abscess, gangrene or in cases not responding (either clinically or radiographically) to apparently appropriate antibiotic treatment. Expert commentary: Research in the past decade has improved diagnosis and treatment of DFO, and most cases can now be managed with a 'conservative' approach, defined as treatment either exclusively with antibiotics or with surgery removing as little bone and soft tissue as necessary.

Antibiotic Resistance in Diabetic Foot Soft Tissue Infections: A Series From Greece

Diabetic foot infections are a common and serious problem for all health systems worldwide. The aim of this study was to examine the resistance to antibiotics of microorganisms isolated from infected soft tissues of diabetic foot ulcers, using tissue cultures. We included 113 consecutive patients (70 men, 43 women) with a mean age of 66.4 ± 11.2 years and a mean diabetes duration of 14.4 ± 7.6 years presenting with diabetic foot soft tissue infections. Generally, no high antibiotic resistance was observed. Piperacillin-tazobactam exhibited the lowest resistance in Pseudomonas, as well as in the other Gram-negative pathogens. In methicillin-resistant Staphylococcus aureus isolates, there was no resistance to anti-Staphylococcus agents. Of note, clindamycin, erythromycin, and amoxycillin/clavulanic acid exhibited high resistance in Gram-positive cocci. These results suggest that antibiotic resistance in infected diabetic foot ulcers in our area is not high and they are anticipated to prove potentially useful in the initial choice of antibiotic regimen.

Efficacy of a New Heparan Sulfate Mimetic Dressing in the Healing of Foot and Lower Extremity Ulcerations in Type 2 Diabetes: A Case Series

A novel heparan sulfate glycosaminoglycan mimetic product for local application to promote wound healing (CACIPLIQ) has recently become available. It is a biophysical therapeutic product comprising a polysaccharide as an innovative biomaterial to accomplish mechanical tissue engineering and skin regeneration in the site of ulceration. We present a series of 12 patients with type 2 diabetes (4 men and 8 women; age 53-87 years; diabetes duration 8-25 years) having chronic resistance to therapy for foot and lower extremity ulcerations. CACIPLIQ was locally applied twice per week after careful debridement. Complete ulcer healing was accomplished in all patients after a mean treatment duration of 4.92 months (range = 2-12 months). The product was very well tolerated. In conclusion, these results, although preliminary, are encouraging and suggest adequate efficacy and safety of the new product in difficult-to-heal foot and lower extremity ulcerations in type 2 diabetes.

Optimising the quality and outcomes of treatments for diabetic foot infections

INTRODUCTION

Infection is the commonest foot complication that arises in people with diabetes and may lead to amputation and even death. The emergence of multidrug resistant bacteria, especially in Gram negative rods, may have a negative impact on the chances of cure in these patients.

AREAS COVERED

We searched the Medline and Pubmed databases for studies using the keywords 'diabetic foot infection' and 'diabetic foot osteomyelits' from 1980 to 2016. Expert commentary: Much has been done in the field of diabetic foot infection regarding pathophysiology, diagnosis and treatment. The construction of multidisciplinary teams is probably the most efficient way to improve the patients' outcome. The rational use of antibiotics and surgical skills are essential in these potentially severe infections. Each case of diabetic infection deserves to be discussed in the light of the current guidelines and the local resources. Because of the overal poor outcome of these infections, prevention remains a priority.

A prospective, multicentre, open-label, single-arm clinical trial for treatment of chronic complex diabetic foot wounds with exposed tendon and/or bone: positive clinical outcomes of viable cryopreserved human placental membrane

Complex diabetic foot ulcers (DFUs) with exposed tendon or bone remain a challenge. They are more susceptible to complications such as infection and amputation and require treatments that promote rapid development of granulation tissue and, ultimately, reepithelialisation. The clinical effectiveness of viable cryopreserved human placental membrane (vCHPM) for DFUs has been established in a level 1 trial. However, complex wounds with exposed deeper structures are typically excluded from randomised controlled clinical trials despite being common in clinical practice. We report the results of a prospective, multicentre, open‐label, single‐arm clinical trial to establish clinical outcomes when vCHPM is applied weekly to complex DFUs with exposed deep structures. Patients with type 1 or type 2 diabetes and a complex DFU extending through the dermis with evidence of exposed muscle, tendon, fascia, bone and/or joint capsule were eligible for inclusion. Of the 31 patients enrolled, 27 completed the study. The mean wound area was 14·6 cm², and mean duration was 7·5 months. For patients completing the protocol, the primary endpoint, 100% wound granulation by week 16, was met by 96·3% of patients in a mean of 6·8 weeks. Complete wound closure occurred in 59·3% (mean 9·1 weeks). The 4‐week percent area reduction was 54·3%. There were no product‐related adverse events. Four patients (13%) withdrew, two (6·5%) for non‐compliance and two (6·5%) for surgical intervention.

Analysis of Ulcer Recurrences After Metatarsal Head Resection in Patients Who Underwent Surgery to Treat Diabetic Foot Osteomyelitis

Metatarsal head resection is a common and standardized treatment used as part of the surgical routine for metatarsal head osteomyelitis. The aim of this study was to define the influence of the amount of the metatarsal resection on the development of reulceration or ulcer recurrence in patients who suffered from plantar foot ulcer and underwent metatarsal surgery. We conducted a prospective study in 35 patients who underwent metatarsal head resection surgery to treat diabetic foot osteomyelitis with no prior history of foot surgeries, and these patients were included in a prospective follow-up over the course of at least 6 months in order to record reulceration or ulcer recurrences. Anteroposterior plain X-rays were taken before and after surgery. We also measured the portion of the metatarsal head that was removed and classified the patients according the resection rate of metatarsal (RRM) in first and second quartiles. We found statistical differences between the median RRM in patients who had an ulcer recurrence and patients without recurrences (21.48 ± 3.10% vs 28.12 ± 10.8%; P = .016). Seventeen (56.7%) patients were classified in the first quartile of RRM, which had an association with ulcer recurrence (P = .032; odds ratio = 1.41; 95% confidence interval = 1.04-1.92). RRM of less than 25% is associated with the development of a recurrence after surgery in the midterm follow-up, and therefore, planning before surgery is undertaken should be considered to avoid postsurgical complications.

Local antibiotic delivery systems in diabetic foot osteomyelitis: time for one step beyond?

In patients with diabetes mellitus, osteomyelitis is a severe, difficult-to-treat form of foot infection. In the management of diabetic foot osteomyelitis, carriers for local delivery of antimicrobial agents have begun to be tried, in an attempt to provide high local antibiotic concentrations. Randomized clinical trials are now expected to clarify when this new approach should be used and how it can be integrated into the overall therapeutic strategy for diabetic foot osteomyelitis.

Conservative Surgery of Diabetic Forefoot Osteomyelitis: How Can I Operate on This Patient Without Amputation?

Surgery is necessary in many cases of diabetic foot osteomyelitis. The decision to undertake surgery should be based on the clinical presentation of diabetic foot osteomyelitis. Surgery is required when the bone is protruding through the ulcer, there is extensive bone destruction seen on x-ray or progressive bone damage on sequential x-ray while undergoing antibiotic treatment, the soft tissue envelope is destroyed, and there is gangrene or spreading soft tissue infection. Several issues should be taken into account when considering surgery for treating diabetic foot osteomyelitis. It is necessary to have a surgeon available with diabetic foot expertise. Regarding location of diabetic foot osteomyelitis, it is important to consider whether isolated bone or a joint is involved. In cases in which osteomyelitis is associated with a bone deformity, surgery should be able to correct this. The surgeon should always reflect about whether extensive/radical surgery could destabilize the foot. The forefoot is the most frequent location of diabetic foot osteomyelitis and is associated with better prognosis than midfoot and hindfoot osteomyelitis. Many surgical procedures can be performed in patients with diabetes and forefoot ulcers complicated by osteomyelitis while avoiding amputations. Performing conservative surgeries without amputations of any part of the foot is not always feasible in cases in which the infection has destroyed the soft tissue envelope. Attempting conservative surgery in such cases risks infected tissues remaining in the wound bed leading to failure. The election of different surgical options depends on the expertise of the surgeons selected for the multidisciplinary teams. It is the aim of this article to provide a sample of surgical techniques in order to remove the bone infection from the forefoot while avoiding amputations.

Ascending infection of foot tendons in diabetic patients

Bone and soft tissue infection in the foot of diabetic patients is a well-described issue in the literature. A sound anatomical knowledge of the foot anatomy and compartments is mandatory to understand the mechanisms of infection spread. We describe four cases of diabetic foot infection complicated by long ascending infection. All did not respond initially to antibiotic treatment and the usual surgical debridement and were cured only after excision of the infected tendons. We highlight a rare but serious complication of the diabetic foot disease not commonly seen by the surgical community. We hope that this report raises the awareness of this condition so that a prompt diagnosis is made and appropriate treatment started, thereby reducing the risk of major lower limb amputations.

Influence of the Location of Nonischemic Diabetic Forefoot Osteomyelitis on Time to Healing After Undergoing Surgery

The forefoot has been reported as the most frequent location of osteomyelitis in the feet of patients with diabetes. The forefoot includes toes and metatarsal heads as common locations of bone infections, but the anatomy of these bones is quite different. As a result, such differences in anatomy may have an impact on the outcomes. The aim of the present study was to determine whether different locations of osteomyelitis in the forefoot have any influence on time to healing after undergoing surgery in a prospective series including 195 patients without peripheral arterial disease and osteomyelitis confirmed by histopathology. Location of the lesion was classified into 4 groups: hallux, first metatarsal head, lesser metatarsal heads, and lesser toes. The time required to achieve healing and the cumulative rate of wounds healed and likelihood of healing were analyzed at 4, 8, and 12 weeks after surgery. Time of healing (mean ± SD) in the whole series was 10.7 ± 8.4 weeks. Osteomyelitis located in the lesser toes has a higher probability of healing by the fourth week (odds ratio [OR] = 5.7, 95% confidence interval [CI] = 2.8-11.6, P < .001), eighth week (OR = 3.2, 95% CI = 1.6-6.4, P < .001), or twelfth week (OR = 3.1, 95% CI = 1.3-7.0, P = .008) than other osteomyelitis locations. Osteomyelitis located in the first metatarsal joint was less likely to heal by the eighth week (OR = 0.4, 95% CI = 0.2-0.9, P = .037) and 12th week (OR = 0.4, 95% CI = 0.2-1.0, P = .040). In conclusion, time to healing is significantly different according to the location of the bone infection in the forefoot.

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.

Diagnosis and management of infection in the diabetic foot

Foot infections are common in persons with diabetes mellitus. Most diabetic foot infections occur in a foot ulcer, which serves as a point of entry for pathogens. Unchecked, infection can spread contiguously to involve underlying tissues, including bone. A diabetic foot infection is often the pivotal event leading to lower extremity amputation, which account for about 60% of all amputations in developed countries. Given the crucial role infections play in the cascade toward amputation, all clinicians who see diabetic patients should have at least a basic understanding of how to diagnose and treat this problem.

Revision Surgery for Diabetic Foot Infections

Revision surgery (RS) is frequently needed to control diabetic foot infections. It is the aim of this retrospective observational study to analyze the variables associated with undergoing RS and the variables associated with undergoing a major amputation when RS was required. We conducted a retrospective study of patients with diabetes treated in our department during 10 years (January 1, 2000 to January 1, 2010) who had foot infections identifying those who required RS. In all, 167 out of 417 patients (40%) with diabetes who underwent surgery for foot infections underwent RS for persistent infection. The predictive variables related to undergoing revision surgery were erythrocyte sedimentation rate >70 mm/h (odds ratio [OR] = 1.6, 95% confidence interval [CI] = 1.1-2.6), leukocytosis (OR = 1.6, 95% CI = 1.1-2.5), peripheral arterial disease (OR = 1.5, 95% CI = 1.0-2.4), and isolation of gram-negative rods from tissue biopsy (OR = 2.2, 95% CI = 1.5-3.4). Seventy-nine out of 167 patients (47.3) who underwent RS required a higher level of surgery achieving a limb salvage rate of 70.7%. Predictive variables related to undergoing a major amputation after RS were persistent infection located in the bone (OR = 0.08, 95% CI = 0.03-0.22), ischemic heart disease (OR = 3.4, 95% CI = 1.4-8.5), 2 or more reoperations (OR = 3.0, 95% CI = 1.2-7.1), isolation of gram-negative rods from tissue biopsy (OR = 3.3, 95% CI = 1.3-8.4), and peripheral arterial disease (OR = 6.5, 95% CI = 1.9-22.8). Despite the fact that 40% of patients underwent reoperations for diabetic foot infections and 47.3% of them required a higher level of surgery, a high rate of limb salvage could be achieved.

Managing diabetic foot infection in India

The burden of diabetic foot complications, in terms of both physical and socioeconomical constraints, poses a heavy challenge both to the patient and the physician, especially in developing countries, where the number of people living with diabetes is increasing at an alarming rate compared with the developed world. In developing countries like India, there are specific causes and risk factors that increase the burden of diabetic foot infections (DFIs), for example, sociocultural risk factors such as barefoot walking, using improper footwear, poor knowledge of foot care practices, lack of adequate and timely access to podiatry services, and poor health care resources. Management of DFI in light of these limitations is quite a challenge to health care professionals. Several techniques and strategies are required to address this problem and should be combined with a multidisciplinary team effort to reduce the burgeoning epidemic of diabetic foot disease. This review is intended to address some of the major aspects of management of DFI in India.

Super-oxidized solution (Dermacyn Wound Care) as adjuvant treatment in the postoperative management of complicated diabetic foot osteomyelitis: preliminary experience in a specialized department

Surgery is usually used to treat diabetic foot osteomyelitis (DFO), whether primarily or in cases in which antibiotics are not able to control infection. In many cases, the bone is only partially removed, which means that residual infection remains in the bone margins, and the wound is left open to heal by secondary intent. The use of culture-guided postoperative antibiotic treatment and adequate management of the wound must be addressed. No trials exist dealing with local treatment in the postoperative management of these cases of complicated DFO. We decided to test a super-oxidized solution, Dermacyn Wound Care (DWC; Oculus Innovative Sciences Netherlands BV, Sittard, Netherlands) to obtain preliminary experience in patients in whom infected bone remained in the surgical wounds. Our hypothesis was that DWC could be useful to control infection in the residual infected bone and surrounding soft tissues and would thus facilitate healing. Fourteen consecutive patients who underwent conservative surgery for DFO, in whom clean bone margins could not be assured, were treated in the postoperative period with DWC. Eleven cases were located in the forefoot, 6 on the first ray and the rest in lesser toes, 1 in the Lisfranc joint, and 2 on the calcaneus. No side effects appeared during treatment. Neither allergies nor skin dermatitis were found. Limb salvage was successfully achieved in 100% of the cases. Healing was achieved in a median period of 6.8 weeks.

From the diabetic foot ulcer and beyond: how do foot infections spread in patients with diabetes?

A diabetic foot infection is usually the result of a pre-existing foot ulceration and is the leading cause of lower extremity amputation in patients with diabetes. It is widely accepted that diabetic foot infections may be challenging to treat for several reasons. The devastating effects of hyperglycemia on host defense, ischemia, multi-drug resistant bacteria and spreading of infection through the foot may complicate the course of diabetic foot infections. Understanding the ways in which infections spread through the diabetic foot is a pivotal factor in order to decide the best approach for the patient's treatment. The ways in which infections spread can be explained by the anatomical division of the foot into compartments, the tendons included in the compartments, the initial location of the point of entry of the infection and the type of infection that the patient has. The aim of this paper is to further comment on the existed and proposed anatomical principles of the spread of infection through the foot in patients with diabetes.

Surgical complications associated with primary closure in patients with diabetic foot osteomyelitis

Background

The aim of this study was to determine the incidence of complications associated with primary closure in surgical procedures performed for diabetic foot osteomyelitis compared to those healed by secondary intention. In addition, further evaluation of the surgical digital debridement for osteomyelitis with primary closure as an alternative to patients with digital amputation was also examined in our study.

Methods

Comparative study that included 46 patients with diabetic foot ulcerations. Surgical debridement of the infected bone was performed on all patients. Depending on the surgical technique used, primary surgical closure was performed on 34 patients (73.9%, Group 1) while the rest of the 12 patients were allowed to heal by secondary intention (26.1%, Group 2). During surgical intervention, bone samples were collected for both microbiological and histopathological analyses. Post-surgical complications were recorded in both groups during the recovery period.

Results

The average healing time was 9.9±SD 8.4 weeks in Group 1 and 19.1±SD 16.9 weeks in Group 2 (p=0.008). The percentage of complications was 61.8% in Group 1 and 58.3% in Group 2 (p=0.834). In all patients with digital ulcerations that were necessary for an amputation, a primary surgical closure was performed with successful outcomes.

Discussion

Primary surgical closure was not associated with a greater number of complications. Patients who received primary surgical closure had faster healing rates and experienced a lower percentage of exudation (p=0.05), edema (p<0.001) and reinfection, factors that determine the delay in wound healing and affect the prognosis of the surgical outcome. Further research with a greater number of patients is required to better define the cases for which primary surgical closure may be indicated at different levels of the diabetic foot.

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.

Clinical–Pathological Characterization of Diabetic Foot Infections

The present study has 3 aims: ( a) to characterize the clinical and pathological features of diabetic foot infections, ( b) to show the range of clinical presentations of moderate infections, and ( c) to analyze the different behavior of diabetic foot osteomyelitis regarding to its clinical presentation. A definitive diagnosis of the type of infection was made based on intraoperative findings and histopathology. Diabetic foot infections were classified into 2 types: soft tissue and bone infections. Mild infections were always superficial. Severe infections included 75% of necrotizing soft tissue infections. Moderate infections showed ample range of clinical presentations. Eighty-one patients presented osteomyelitis. Osteomyelitis was further classified as follows: osteomyelitis without ischemia and without soft tissue involvement (class 1), osteomyelitis with ischemia without soft tissue involvement (class 2), osteomyelitis with soft tissue involvement (class 3), and osteomyelitis with ischemia and soft tissue involvement (class 4). Forty-eight patients (59.3%) with osteomyelitis underwent conservative surgery, 32 (39.5%) had minor amputations including 9 open transmetatarsal amputations, and there was 1 (1.2%) major amputation. The characterization of osteomyelitis into 4 classes showed a statistically significant trend toward increased severity and increased amputation rate and mortality. In conclusion, the clinical presentation of foot infections in diabetic patients is very heterogeneous and can be classified into soft tissue infections (cellulitis, superficial and deep abscesses, and necrotizing soft tissue infections) and osteomyelitis, which was the most frequent type of infection found in the author’s series. Their division into 4 classes showed a statistically significant trend toward increased severity, amputation rate, and mortality. The diagnosis of deep soft tissue infections associated with osteomyelitis may be difficult to achieve before surgery.

Evidences and Controversies About Recurrence of Diabetic Foot Osteomyelitis

Recurrence is one of the most worrying issues when dealing with diabetic foot osteomyelitis (DFO). In accordance with expert opinion in other areas of bone infection, it is accepted that very late relapse of apparently successfully treated osteomyelitis is not uncommon. However, the physiopathology of infections in large bones secondary to hematogenous osteomyelitis, infected prostheses, and open fractures is quite different from what is seen in the feet of patients with diabetes. The anatomy of the bones, the mechanism of infection and alterations in host defenses that are frequently seen in patients with diabetes may condition the onset, clinical course, and outcomes. Apparent eradication, disappearance of inflammatory signs, wound healing, bone healing based on image studies, and no recurrences during follow-up are common terms used for defining the success of therapy for DFO. Failure of initial surgical treatment, readmission to hospital, and new episodes of infection at the same or a contiguous site are considered as recurrence of osteomyelitis. Theoretically, bacteria living in the bone could be the source of clinical recurrence, but is it possible to obtain complete healing while bacteria remain alive in the bone in the feet of patients with diabetes? Can these bacteria grow and spread from the bone to the skin after years of healing? In the author’s opinion, this type of long-term recurrence of DFO has not been well documented in the medical literature. It is the aim of this illustrated guide to review the evidence and controversies regarding the recurrence of DFO.

Expert opinion on the management of infections in the diabetic foot

This update of the International Working Group on the Diabetic Foot incorporates some information from a related review of diabetic foot osteomyelitis (DFO) and a systematic review of the management of infection of the diabetic foot. The pathophysiology of these infections is now well understood, and there is a validated system for classifying the severity of infections based on their clinical findings. Diagnosing osteomyelitis remains difficult, but several recent publications have clarified the role of clinical, laboratory and imaging tests. Magnetic resonance imaging has emerged as the most accurate means of diagnosing bone infection, but bone biopsy for culture and histopathology remains the criterion standard. Determining the organisms responsible for a diabetic foot infection via culture of appropriately collected tissue specimens enables clinicians to make optimal antibiotic choices based on culture and sensitivity results. In addition to culture-directed antibiotic therapy, most infections require some surgical intervention, ranging from minor debridement to major resection, amputation or revascularization. Clinicians must also provide proper wound care to ensure healing of the wound. Various adjunctive therapies may benefit some patients, but the data supporting them are weak. If properly treated, most diabetic foot infections can be cured. Providers practising in developing countries, and their patients, face especially challenging situations.

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.

Never Amputate a Patient With Diabetes Without Consulting With a Specialized Unit

This study presents a case report of a patient who underwent a severe infection following revascularization because dry necrosis became infected. A major amputation had been indicated because the infection did not respond to antibiotics and advanced wound care with topical negative pressure wound therapy with silver. The patient did not accept the major amputation and attended the authors’ specialized unit. Persistent osteomyelitis was diagnosed with a simple X-ray, a cheap tool. Local surgery, antibiotics, appropriate wound care, and split-skin grafting achieved limb salvage in 12 weeks in this patient who had been scheduled for major amputation. Major amputation in patients with an infected foot can sometimes be avoided by correct diagnosis of infection and managing appropriately with specialized support.