Effects of granulocyte-colony stimulating factor in the treatment of diabetic foot infection

Distinct plasma chemokines and cytokines signatures in Leishmania guyanensis-infected patients with cutaneous leishmaniasis

The immunopathology associated with Leishmaniasis is a consequence of inflammation. Upon infection with Leishmania, the type of host-immune response is determinant for the clinical manifestations that can lead to either self-healing or chronic disease. Multiple pathways may determine disease severity. A comparison of systemic immune profiles in patients with cutaneous leishmaniasis caused by L. guyanensis and healthy individuals with the same socio-epidemiological characteristics coming from the same endemic areas as the patients is performed to identify particular immune profile and pathways associated with the progression of disease development. Twenty-seven plasma soluble circulating factors were evaluated between the groups by univariate and multivariate analysis. The following biomarkers pairs IL-17/IL-9 (ρ=0,829), IL-17/IL-12 (ρ=0,786), IL-6/IL-1ra (ρ=0,785), IL-6/IL-12 (ρ=0,780), IL-1β/G-CSF (ρ=0,758) and IL-17/MIP-1β (ρ=0,754) showed the highest correlation mean among the patient while only INF-γ/IL-4 (ρ=0.740), 17/MIP-1β (ρ=0,712) and IL-17/IL-9 (ρ=0,707) exhibited positive correlation among the control group. The cytokine IL-17 and IL1β presented the greater number of positive pair correlation among the patients. The linear combinations of biomarkers displayed IP-10, IL-2 and RANTES as the variables with the higher discriminatory activity in the patient group compared to PDGF, IL-1ra and eotaxin among the control subjects. IP-10, IL-2, IL-1β, RANTES and IL-17 seem to be predictive value of progression to the development of disease among the Lg-infected individuals.

A Bittersweet Response to Infection in Diabetes; Targeting Neutrophils to Modify Inflammation and Improve Host Immunity

Chronic and recurrent infections occur commonly in both type 1 and type 2 diabetes (T1D, T2D) and increase patient morbidity and mortality. Neutrophils are professional phagocytes of the innate immune system that are critical in pathogen handling. Neutrophil responses to infection are dysregulated in diabetes, predominantly mediated by persistent hyperglycaemia; the chief biochemical abnormality in T1D and T2D. Therapeutically enhancing host immunity in diabetes to improve infection resolution is an expanding area of research. Individuals with diabetes are also at an increased risk of severe coronavirus disease 2019 (COVID-19), highlighting the need for re-invigorated and urgent focus on this field. The aim of this review is to explore the breadth of previous literature investigating neutrophil function in both T1D and T2D, in order to understand the complex neutrophil phenotype present in this disease and also to focus on the development of new therapies to improve aberrant neutrophil function in diabetes. Existing literature illustrates a dual neutrophil dysfunction in diabetes. Key pathogen handling mechanisms of neutrophil recruitment, chemotaxis, phagocytosis and intracellular reactive oxygen species (ROS) production are decreased in diabetes, weakening the immune response to infection. However, pro-inflammatory neutrophil pathways, mainly neutrophil extracellular trap (NET) formation, extracellular ROS generation and pro-inflammatory cytokine generation, are significantly upregulated, causing damage to the host and perpetuating inflammation. Reducing these proinflammatory outputs therapeutically is emerging as a credible strategy to improve infection resolution in diabetes, and also more recently COVID-19. Future research needs to drive forward the exploration of novel treatments to improve infection resolution in T1D and T2D to improve patient morbidity and mortality.

Deregulated immune cell recruitment orchestrated by FOXM1 impairs human diabetic wound healing

Diabetic foot ulcers (DFUs) are a life-threatening disease that often result in lower limb amputations and a shortened lifespan. However, molecular mechanisms contributing to the pathogenesis of DFUs remain poorly understood. We use next-generation sequencing to generate a human dataset of pathogenic DFUs to compare to transcriptional profiles of human skin and oral acute wounds, oral as a model of “ideal” adult tissue repair due to accelerated closure without scarring. Here we identify major transcriptional networks deregulated in DFUs that result in decreased neutrophils and macrophages recruitment and overall poorly controlled inflammatory response. Transcription factors FOXM1 and STAT3, which function to activate and promote survival of immune cells, are inhibited in DFUs. Moreover, inhibition of FOXM1 in diabetic mouse models (STZ-induced and db/db) results in delayed wound healing and decreased neutrophil and macrophage recruitment in diabetic wounds in vivo. Our data underscore the role of a perturbed, ineffective inflammatory response as a major contributor to the pathogenesis of DFUs, which is facilitated by FOXM1-mediated deregulation of recruitment of neutrophils and macrophages, revealing a potential therapeutic strategy.

Diabetic foot ulcers (DFU) represent a complex disease with limited treatment options. Here, the authors compare human RNASeq patient data from DFU, oral mucosa and skin acute wounds, identifying FOXM1 as a mediator of macrophage and neutrophil recruitment, which contributes to disease pathogenesis and is dysregulated in patients.

Advances in the Research of Bioinks Based on Natural Collagen, Polysaccharide and Their Derivatives for Skin 3D Bioprinting

The skin plays an important role in protecting the human body, and wound healing must be set in motion immediately following injury or trauma to restore the normal structure and function of skin. The extracellular matrix component of the skin mainly consists of collagen, glycosaminoglycan (GAG), elastin and hyaluronic acid (HA). Recently, natural collagen, polysaccharide and their derivatives such as collagen, gelatin, alginate, chitosan and pectin have been selected as the matrix materials of bioink to construct a functional artificial skin due to their biocompatible and biodegradable properties by 3D bioprinting, which is a revolutionary technology with the potential to transform both research and medical therapeutics. In this review, we outline the current skin bioprinting technologies and the bioink components for skin bioprinting. We also summarize the bioink products practiced in research recently and current challenges to guide future research to develop in a promising direction. While there are challenges regarding currently available skin bioprinting, addressing these issues will facilitate the rapid advancement of 3D skin bioprinting and its ability to mimic the native anatomy and physiology of skin and surrounding tissues in the future.

Effectiveness of interventions to enhance healing of chronic foot ulcers in diabetes: a systematic review

The management of diabetic foot ulcers (DFU) remains a challenge, and there is continuing uncertainty concerning optimal approaches to wound healing. The International Working Group of the Diabetic Foot (IWGDF) working group on wound healing has previously published systematic reviews of the evidence in 2008, 2012 and 2016 to inform protocols for routine care and to highlight areas which should be considered for further study. The working group has now updated this review by considering papers on the interventions to improve the healing of DFU's published between June 2014 and August 2018. Methodological quality of selected studies was independently assessed by a minimum of two reviewers using the recently published 21-point questionnaire as recommended by IWGDF/European Wound Management Association, as well as the previously incorporated Scottish Intercollegiate Guidelines Network criteria. Of the 2275 papers identified, 97 were finally selected for grading following full text review. Overall, there has been an improvement in study design and a significant rise in the number of published studies. While previous systematic reviews did not find any evidence to justify the use of newer therapies, except for negative pressure wound therapy in post-surgical wounds, in this review we found additional evidence to support some interventions including a sucrose-octasulfate dressing, the combined leucocyte, fibrin and platelet patch as well as topical application of some placental membrane products, all when used in addition to usual best care. Nonetheless, the assessment and comparison of published trials remains difficult with marked clinical heterogeneity between studies: in patient selection, study duration, standard of usual care provision and the timing and description of the clinical endpoints.

Interventions in the management of infection in the foot in diabetes: a systematic review

The optimal approaches to managing diabetic foot infections remain a challenge for clinicians. Despite an exponential rise in publications investigating different treatment strategies, the various agents studied generally produce comparable results, and high-quality data are scarce. In this systematic review, we searched the medical literature using the PubMed and Embase databases for published studies on the treatment of diabetic foot infections as of June 2018. This systematic review is an update of previous reviews, the first of which was undertaken in 2010 and the most recent in 2014, by the infection committee of the International Working Group of the Diabetic Foot. We defined the context of literature by formulating clinical questions of interest, then developing structured clinical questions (PICOs) to address these. We only included data from controlled studies of an intervention to prevent or cure a diabetic foot infection. Two independent reviewers selected articles for inclusion and then assessed their relevant outcomes and the methodological quality. Our literature search identified a total of 15 327 articles, of which we selected 48 for full-text review; we added five more studies discovered by means other than the systematic literature search. Among these selected articles were 11 high-quality studies published in the last 4 years and two Cochrane systematic reviews. Overall, the outcomes in patients treated with the different antibiotic regimens for both skin and soft tissue infection and osteomyelitis of the diabetic foot were broadly equivalent across studies, except that treatment with tigecycline was inferior to ertapenem (±vancomycin). Similar outcomes were also reported in studies comparing primarily surgical and predominantly antibiotic treatment strategies in selected patients with diabetic foot osteomyelitis. There is insufficient high-quality evidence to assess the effect of various adjunctive therapies, such as negative pressure wound therapy, topical ointments or hyperbaric oxygen, on infection related outcomes of the diabetic foot. In general, the quality of more recent trial designs are better in past years, but there is still a great need for further well-designed trials to produce higher quality evidence to underpin our recommendations.

The Role of Recombinant Proteins and Growth Factors in the Management of Diabetic Foot Ulcers: A Systematic Review of Randomized Controlled Trials

BACKGROUND

Recombinant proteins and growth factors are emerging therapies for diabetic foot ulcers. Despite several clinical reports, there has been no comprehensive and systematic assessment of the totality of clinical evidence on the efficacy and safety of recombinant proteins and growth factors in diabetic foot ulcers. We tried to address this gap through an updated systematic review of randomized controlled trials (RCTs).

METHODS

PubMed, the Cochrane Library, Scopus, Embase, and Google Scholar databases were searched, and RCTs on the efficacy of recombinant proteins and growth factors in the treatment of cutaneous wounds in diabetic patients were selected. The literature search and assessment were performed by two independent reviewers. Methodological quality of studies was appraised using the Jadad scale.

RESULTS

We identified 26 RCTs involving diabetic patients with ulcer that evaluated the effectiveness of platelet-derived growth factor, epidermal growth factor, fibroblast growth factor, granulocyte colony-stimulating factor, vascular endothelial growth factor, erythropoietin, transforming growth factor, talactoferrin, and rusalatide acetate. The main primary outcome was complete healing though different indices were employed to define this such as wound closure, granulation tissue formation, or complete reepithelialization. Few studies had a follow-up period to report any recurrence and amputation rate. No adverse effect was reported due to the intervention.

CONCLUSION

Overall, there is a greater agreement on the effectiveness of EGF to enhance the healing of diabetic ulcers. Nevertheless, extant evidence is lacking for other agents since few trials have been conducted for most of the growth factors and available studies are heterogeneous in their methodologies.

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.

Systemic scleroderma: An approach from plastic surgery

Introducción. La esclerosis sistémica (ES) es una enfermedad autoinmune del tejido conectivo que se caracteriza clínicamente por un engrosamiento cutáneo, el cual se da debido a la acumulación de tejido conectivo y puede afectar a otros órganos y a las extremidades. La etiología multifactorial de esta enfermedad corresponde a la interacción de alteraciones en el remodelamiento de la matriz extracelular, función inmunitaria y presencia de vasculopatía proliferativa bajo influencia genética y medioambiental.Objetivo. Realizar una revisión sobre el manejo médico y quirúrgico desde el punto de vista de la cirugía plástica de las lesiones en piel y manos y las alteraciones faciales de los pacientes con ES.Materiales y métodos. Se realizó una búsqueda bibliográfica en las bases de datos Medline, LILACS, PubMed, EMBASE y Current contents con las palabras claves esclerodermia sistémica, cirugía plástica, mano y ulceras.Resultados. La ES requiere manejo multidisciplinario; se presentan casos en los que se indica terapia farmacológica y otros en los que el manejo es quirúrgico complementario.Conclusión. Esta patología afecta de manera importante la piel al provocar lesiones que van desde ulceras digitales hasta atrofia facial, las cuales son susceptibles de manejo por el área de cirugía plástica.

Pharmacotherapy of Diabetic Foot Ulcers

The incidence of diabetes and diabetic foot ulcers is increasing significantly in the United States. These ulcers and infections are the result of long-term complications of diabetes including neuropathy and vascular insufficiency. These infections can be classified into mild, limb threatening, and life threatening. This classification helps clarify the expected organisms involved and consequently appropriate, empiric antibiotic therapy. Mild infections are generally caused by Gram-positive organisms and can usually be treated as an outpatient with oral antibiotics. Antibiotics used for mild infections-include cephalexin, clindamycin, and amoxicillin/ clavulanate. Moderate to severe or limb-threatening infections are usually polymicrobial and frequently require hospitalization. These infections are typically treated with more broad-spectrum antibiotics including ampicillin/sulbactam, imipenem, or the combination of clindamycin and a fluoroquinolone. Severe or life-threatening infections also require broad-spectrum antibiotics. Other therapeutic options besides antibiotics include growth factors, such as becaplermin, and various skin substitutes.

Effectiveness of interventions to enhance healing of chronic ulcers of the foot in diabetes: a systematic review

The outcome of management of diabetic foot ulcers remains a challenge, and there remains continuing uncertainty concerning optimal approaches to management. It is for these reasons that in 2008 and 2012, the International Working Group of the Diabetic Foot (IWGDF) working group on wound healing published systematic reviews of the evidence to inform protocols for routine care and to highlight areas, which should be considered for further study. The same working group has now updated this review by considering papers on the interventions to improve the healing of chronic ulcers published between June 2010 and June 2014. Methodological quality of selected studies was independently assessed by two reviewers using Scottish Intercollegiate Guidelines Network criteria. Selected studies fell into the following ten categories: sharp debridement and wound bed preparation with larvae or hydrotherapy; wound bed preparation using antiseptics, applications and dressing products; resection of the chronic wound; oxygen and other gases, compression or negative pressure therapy; products designed to correct aspects of wound biochemistry and cell biology associated with impaired wound healing; application of cells, including platelets and stem cells; bioengineered skin and skin grafts; electrical, electromagnetic, lasers, shockwaves and ultrasound and other systemic therapies, which did not fit in the aforementioned categories. Heterogeneity of studies prevented pooled analysis of results. Of the 2161 papers identified, 30 were selected for grading following full text review. The present report is an update of the earlier IWGDF systematic reviews, and the conclusion is similar: that with the possible exception of negative pressure wound therapy in post-operative wounds, there is little published evidence to justify the use of newer therapies. Analysis of the evidence continues to present difficulties in this field as controlled studies remain few and the majority continue to be of poor methodological quality.

Interventions in the management of infection in the foot in diabetes: a systematic review

The expert panel on diabetic foot infection (DFI) of the International Working Group on the Diabetic Foot conducted a systematic review seeking all published reports relating to any type of treatment for infection of the foot in persons with diabetes published as of 30 June 2014. This review, conducted with both PubMed and EMBASE, was used to update an earlier one undertaken on 30 June 2010 using the same search string. Eligible publications included those that had outcome measures reported for both a treated and a control population that were managed either at the same time, or as part of a before-and-after case design. We did not include studies that contained only information related to definition or diagnosis, but not treatment, of DFI. The current search identified just seven new articles meeting our criteria that were published since the 33 identified with the previous search, making a total of 40 articles from the world literature. The identified articles included 37 randomised controlled trials (RCTs) and three cohort studies with concurrent controls, and included studies on the use of surgical procedures, topical antiseptics, negative pressure wound therapy and hyperbaric oxygen. Among the studies were 15 RCTs that compared outcomes of treatment with new antibiotic preparations compared with a conventional therapy in the management of skin and soft tissue infection. In addition, 10 RCTs and 1 cohort study compared different treatments for osteomyelitis in the diabetic foot. Results of comparisons of different antibiotic regimens generally demonstrated that newly introduced antibiotic regimens appeared to be as effective as conventional therapy (and also more cost-effective in one study), but one study failed to demonstrate non-inferiority of a new antibiotic compared with that of a standard agent. Overall, the available literature was both limited in both the number of studies and the quality of their design. Thus, our systematic review revealed little evidence upon which to make recommendations for treatment of DFIs. There is a great need for further well-designed trials that will provide robust data upon which to make decisions about the most appropriate treatment of both skin and soft tissue infection and osteomyelitis in diabetic patients.

Strategy of surgical management of peripheral neuropathy form of diabetic foot syndrome in ghana

Introduction. Foot disorders such as ulceration, infection, and gangrene which are often due to diabetes mellitus are some major causes of morbidity and high amputation. Aim. This study aims to use a group of methods for the management of diabetic foot ulcers (DFU) in order to salvage the lower limb so as to reduce the rate of high amputations of the lower extremity. Materials and Methods. A group of different advanced methods for the management of DFU such as sharp debridement of ulcers, application of vacuum therapy, and other forms of reconstructive plastic surgical procedures were used. Data collection was done at 3 different hospitals where the treatments were given. Results. Fifty-four patients with type 2 diabetes mellitus were enrolled in the current study: females n = 37 (68.51%) and males n = 17 (31.49%) with different stages of PEDIS classification. They underwent different methods of surgical management: debridement, vacuum therapy (some constructed from locally used materials), and skin grafting giving good and fast results. Only 4 had below knee amputations. Conclusion. Using advanced surgical wound management including reconstructive plastic surgical procedures, it was possible to reduce the rate of high amputations of the lower limb.

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.

Granulocyte-colony stimulating factors as adjunctive therapy for diabetic foot infections

BACKGROUND

Granulocyte-colony stimulating factor (G-CSF) increases the release of neutrophil endothelial progenitor cells from the bone marrow and improves neutrophil functions, which are often impaired in people with diabetes.

OBJECTIVES

To examine the effects of adjunctive G-CSF compared with placebo or no growth factor added to usual care on rates of infection, cure and wound healing in people with diabetes who have a foot infection.

SEARCH METHODS

In March 2013, for this second update, we searched the Cochrane Wounds Group Specialised Register (searched 14 March 2013); the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2013, Issue 2); Ovid MEDLINE (1948 to March Week 1 2013); Ovid EMBASE (1974 to 2013 March 13); Ovid MEDLINE (In-Process march 13,2013); and EBSCO CINAHL (1982 to 28 February 2013).

SELECTION CRITERIA

Randomised controlled trials (RCTs) that evaluated the effect of adding G-CSF to usual care in people with a diabetic foot infection.

DATA COLLECTION AND ANALYSIS

Three review authors independently assessed trial eligibility, methodological quality and extracted data. We reported risk ratio (RR) or, for continuous outcomes, mean differences (MD), with 95% confidence intervals (CI). In the case of low or no heterogeneity we pooled studies using a fixed-effect model.

MAIN RESULTS

We identified and included five eligible trials with a total of 167 patients. The investigators administered various G-CSF preparations, at different doses and for different durations of time. Adding G-CSF did not significantly affect the likelihood of resolution of infection or wound healing, but it was associated with a significantly reduced likelihood of lower extremity surgical interventions (RR 0.38; 95 % CI 0.21 to 0.70), including amputation (RR 0.41; 95 % CI 0.18 to 0.95). Moreover, providing G-CSF reduced the duration of hospital stay (MD -1.40 days; 95% CI -2.27 to -0.53 days), but did not significantly affect the duration of systemic antibiotic therapy (MD -0.27 days; 95% CI -1.30 to 0.77 days).

AUTHORS' CONCLUSIONS

The available evidence is limited, but suggests that adjunctive G-CSF treatment in people with a diabetic foot infection, including infected ulcers, does not appear to increase the likelihood of resolution of infection or healing of the foot ulcer. However, it does appear to reduce the need for surgical interventions, especially amputations, and the duration of hospitalisation. Clinicians might consider adding G-CSF to the usual treatment of diabetic foot infections, especially in patients with a limb-threatening infection, but it is not clear which patients might benefit.

A pilot study evaluating non-contact low-frequency ultrasound and underlying molecular mechanism on diabetic foot ulcers

Non-contact low-frequency ultrasound (NCLF-US) devices have been increasingly used for the treatment of chronic non-healing wounds. The appropriate dose for NCLF-US is still in debate. The aims of this pilot study were to evaluate the relationship between dose and duration of treatment for subjects with non-healing diabetic foot ulcers (DFUs) and to explore the correlation between wound healing and change of cytokine/proteinase/growth factor profile. This was a prospective randomised clinical study designed to evaluate subjects with non-healing DFUs for 5 weeks receiving standard of care and/or NCLF-US treatment. Subjects were randomly assigned to one of the three groups: application of NCLF-US thrice per week (Group 1), NCLF-US once per week (Group 2) and the control (Group 3) that received no NCLF-US. All subjects received standard wound care plus offloading for a total of 4 weeks. Percent area reduction (PAR) of each wound compared with baseline was evaluated weekly. Profiles of cytokines/proteinase/growth factors in wound fluid and biopsied tissue were quantified to explore the correlation between wound healing and cytokines/growth factor expression. Twelve DFU patients, 2 (16·7%) type 1 and 10 (83·3%) type 2 diabetics, with an average age of 58 ± 10 years and a total of 12 foot ulcers were enrolled. Average ulcer duration was 36·44 ± 24·78 weeks and the average ABI was 0·91 ± 0·06. Group 1 showed significant wound area reduction at weeks 3, 4 and 5 compared with baseline, with the greatest PAR, 86% (P < 0·05); Groups 2 and 3 showed 25% PAR and 39% PAR, respectively, but there were no statistically significant differences between Groups 2 and 3 over time. Biochemical and histological analyses indicated a trend towards reduction of pro-inflammatory cytokines (IL-6, IL-8, IL-1β, TNF-α and GM-CSF), matrix metalloproteinase-9 (MMP-9), vascular endothelial growth factor (VEGF) and macrophages in response to NCLF-US consistent with wound reduction, when compared with control group subjects. This proof-of-concept pilot study demonstrates that NCLF-US is effective in treating neuropathic diabetic foot ulcers through, at least in part, inhibiting pro-inflammatory cytokines in chronic wound and improving tissue regeneration. Therapeutic application of NFLU, thrice (3) per week, renders the best wound area reduction.

Management of diabetic foot ulcers

Diabetic foot is a serious complication of diabetes which aggravates the patient's condition whilst also having significant socioeconomic impact. The aim of the present review is to summarize the causes and pathogenetic mechanisms leading to diabetic foot, and to focus on the management of this important health issue. Increasing physicians' awareness and hence their ability to identify the "foot at risk," along with proper foot care, may prevent diabetic foot ulceration and thus reduce the risk of amputation.

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.

Diagnostics and treatment of the diabetic foot

Every 30 s, a lower limb is amputated due to diabetes. Of all amputations in diabetic patients 85% are preceded by a foot ulcer which subsequently deteriorates to a severe infection or gangrene. There is a complexity of factors related to healing of foot ulcers including strategies for treatment of decreased perfusion, oedema, pain, infection, metabolic disturbances, malnutrition, non-weight bearing, wound treatment, foot surgery, and management of intercurrent disease. Patients with diabetic foot ulcer and decreased perfusion do often not have rest pain or claudication and as a consequence non-invasive vascular testing is recommended for early recognition of ulcers in need of revascularisation to achieve healing. A diabetic foot infection is a potentially limb-threatening condition. Infection is diagnosed by the presence or increased rate of signs inflammation. Often these signs are less marked than expected. Imaging studies can diagnose or better define deep, soft tissue purulent collections and are frequently needed to detect pathological findings in bone. The initial antimicrobial treatment as well as duration of treatment is empiric. There is a substantial delay in wound healing in diabetic foot ulcer which has been related to various abnormalities. Several new treatments related to these abnormalities have been explored in wound healing with various successes. An essential part of the strategy to achieve healing is an effective offloading. Many interventions with advanced wound management have failed due to not recognizing the need for effective offloading. A multidisciplinary approach to wounds and foot ulcer has been successfully implemented in different centres with a substantial decrease in amputation rate.

A systematic review of the effectiveness of interventions in the management of infection in the diabetic foot

The International Working Group on the Diabetic Foot expert panel on infection conducted a systematic review of the published evidence relating to treatment of foot infection in diabetes. Our search of the literature published prior to August 2010 identified 7517 articles, 29 of which fulfilled predefined criteria for detailed data extraction. Four additional eligible papers were identified from other sources. Of the total of 33 studies, 29 were randomized controlled trials, and four were cohort studies. Among 12 studies comparing different antibiotic regimens in the management of skin and soft-tissue infection, none reported a better response with any particular regimen. Of seven studies that compared antibiotic regimens in patients with infection involving both soft tissue and bone, one reported a better clinical outcome in those treated with cefoxitin compared with ampicillin/sulbactam, but the others reported no differences between treatment regimens. In two health economic analyses, there was a small saving using one regimen versus another. No published data support the superiority of any particular route of delivery of systemic antibiotics or clarify the optimal duration of antibiotic therapy in either soft-tissue infection or osteomyelitis. In one non-randomized cohort study, the outcome of treatment of osteomyelitis was better when the antibiotic choice was based on culture of bone specimens as opposed to wound swabs, but this study was not randomized, and the results may have been affected by confounding factors. Results from two studies suggested that early surgical intervention was associated with a significant reduction in major amputation, but the methodological quality of both was low. In two studies, the use of superoxidized water was associated with a better outcome than soap or povidone iodine, but both had a high risk of bias. Studies using granulocyte-colony stimulating factor reported mixed results. There was no improvement in infection outcomes associated with hyperbaric oxygen therapy. No benefit has been reported with any other intervention, and, overall, there are currently no trial data to justify the adoption of any particular therapeutic approach in diabetic patients with infection of either soft tissue or bone of the foot.

New insights in diabetic foot infection

Foot ulcers are common in diabetic patients, have a cumulative lifetime incidence rate as high as 25% and frequently become infected. The spread of infection to soft tissue and bone is a major causal factor for lower-limb amputation. For this reason, early diagnosis and appropriate treatment are essential, including treatment which is both local (of the foot) and systemic (metabolic), and this requires coordination by a multidisciplinary team. Optimal treatment also often involves extensive surgical debridement and management of the wound base, effective antibiotic therapy, consideration for revascularization and correction of metabolic abnormalities such as hyperglycemia. This article focuses on diagnosis and management of diabetic foot infections in the light of recently published data in order to help clinicians in identification, assessment and antibiotic therapy of diabetic foot infections.

Granulocyte-colony stimulating factors as adjunctive therapy for diabetic foot infections

BACKGROUND

G-CSF increases the release of neutrophil endothelial progenitor cells from the bone marrow, and improves neutrophil functions, which are often impaired in people with diabetes.

OBJECTIVES

To examine the effects of adjunctive G-CSF compared with placebo or no growth factor added to usual care on rates of infection, cure and wound healing in people with diabetes who have a foot infection.

SEARCH STRATEGY

We searched the Cochrane Wounds Group Specialised Register (Searched 16/3/09); the Cochrane Central Register of Controlled Trials (The Cochrane Library, issue 1 2009); Ovid MEDLINE (1950 to March Week 1 2009); Ovid EMBASE (1980 to 2009 Week 11); EBSCO CINAHL (1982 to March Week 2 2009); LookSmart's Find Articles (January 1990 to January 2008); conference proceedings and references lists in the included studies.

SELECTION CRITERIA

Randomised controlled trials (RCTs) that evaluated the effect of adding G-CSF to usual care in people with a diabetic foot infection.

DATA COLLECTION AND ANALYSIS

Three review authors independently assessed trial eligibility, methodological quality and extracted data. Relative risk (RR), or for continuous outcomes, mean differences (MD), with 95% confidence intervals (CI) were reported. In the case of low or no heterogeneity studies were pooled using a fixed-effect model.

MAIN RESULTS

We identified and included five eligible trials with a total of 167 patients. The investigators administered various G-CSF preparations, at different doses and for different durations of time. Adding G-CSF did not significantly affect the likelihood of resolution of infection or wound healing, but it was associated with a significantly reduced likelihood of lower extremity surgical interventions (RR 0.37; 95 % CI 0.20 to 0.68), including amputation (RR 0.41; 95 % CI 0.18 to 0.95). Moreover, providing G-CSF reduced the duration of hospital stay (MD, -1.40 days; 95 % CI, -2.27 to -0.53 days), but did not significantly affect the duration of systemic antibiotic therapy (MD, -0.27 days; 95 % CI, -1.30 to 0.77 days).

AUTHORS' CONCLUSIONS

The available evidence is limited, but suggests that adjunctive G-CSF treatment in people with a diabetic foot infection, including infected ulcers, does not appear to increase the likelihood of resolution of infection or healing of the foot ulcer. However, it does appear to reduce the need for surgical interventions, especially amputations, and the duration of hospitalisation. Clinicians might consider adding G-CSF to the usual treatment of diabetic foot infections, especially in patients with a limb-threatening infection, but it is not clear which patients might benefit.

A systematic review of the effectiveness of interventions to enhance the healing of chronic ulcers of the foot in diabetes

The outcome of management of diabetic foot ulcers is poor and there is uncertainty concerning optimal approaches to management. We have undertaken a systematic review to identify interventions for which there is evidence of effectiveness. A search was made for reports of the effectiveness of interventions assessed in terms of healing, ulcer area or amputation in controlled clinical studies published prior to December 2006. Methodological quality of selected studies was independently assessed by two reviewers using Scottish Intercollegiate Guidelines Network (SIGN) criteria. Selected studies fell into the following categories: sharp debridement and larvae; antiseptics and dressings; chronic wound resection; hyperbaric oxygen (HBO); reduction of tissue oedema; skin grafts; electrical and magnetic stimulation and ultrasound. Heterogeneity of studies prevented pooled analysis of results. Of the 2251 papers identified, 60 were selected for grading following full text review. Some evidence was found to support hydrogels as desloughing agents and to suggest that a systemic (HBO) therapy may be effective. Topical negative pressure (TNP) may promote healing of post-operative wounds, and resection of neuropathic plantar ulcers may be beneficial. More information was needed to confirm the effectiveness and cost-effectiveness of these and other interventions. No data were found to justify the use of any other topically applied product or dressing, including those with antiseptic properties. Further evidence to substantiate the effect of interventions designed to enhance the healing of chronic ulcers is urgently needed. Until such evidence is available from robust trials, there is limited justification for the use of more expensive treatments and dressings.

Infections in Diabetes Mellitus and Hyperglycemia

Infections in diabetes mellitus are relatively more common and serious. Diabetic patients run the risk of acute metabolic decompensation during infections, and conversely patients with metabolic decompensation are at higher risk of certain invasive infections. Tight glycemic control is of paramount importance during acute infected or high stress state. Infections in diabetic patients result in extended hospital stays and additional financial burden. Given the risks of not alleviating the metabolic dysregulation and the benefits of decent glycemic control, it is necessary that besides antimicrobial therapy, equal emphasis be placed on intensified glycemic control.

Growth factors in the treatment of diabetic foot ulcers: new technologies, any promises?

Foot ulcers remain a common problem, leading to increased morbidity in patients with diabetes. Despite the progress that has been achieved in revascularization techniques as well as in off-loading to relieve high-pressure areas, diabetic foot wounds remain a clinical challenge. Growth factors are a major technological advance that promised to change the face of wound healing. The most important of growth factors are recombinant human platelet-derived growth factor-BB and granulocyte colony-stimulating factor. The former has been approved by the FDA for the treatment of neuropathic ulcers when there is adequate blood supply. The latter is less demonstrably useful. Advances include methods of delivering growth factors.

Perioperative prophylaxis with granulocyte colony-stimulating factor (G-CSF) in high-risk colorectal cancer patients for an improved recovery: A randomized, controlled trial

BACKGROUND

We aimed to improve the postoperative outcome of high-risk patients (American Society of Anesthesiologists class 3 and 4) recovering from colorectal cancer surgery by using recombinant human G-CSF (filgrastim) as perioperative prophylaxis.

METHODS

In a double-blinded, placebo-controlled trial, 80 patients undergoing left-sided colorectal resection were randomized to filgrastim or placebo. Filgrastim (5 mug/kg) or placebo was administered in the afternoon on day -1, 0, and +1 relative to the operation. Primary endpoints were in a hierarchic order: quality of life (QoL) over time (determined at discharge, 2 and 6 months after operation with the European Organization for Research and Treatment of Cancer questionnaire) and the McPeek recovery score, which measures death and duration of stays in the intensive care unit and hospital. Predefined secondary endpoints were global QoL, subdomains of QoL, postoperative recovery, duration of stay, 6-month overall survival, complication rates, and cellular and immunologic parameters.

RESULTS

There were no significant differences in both primary endpoints between the treatment groups. A significant improvement (P < .05) was obtained by filgrastim prophylaxis in the QoL subdomain family life /- social functioning,; thus, more patients recovered to their preoperative state (14 vs 4 with placebo) as determined by structured interviews. Duration of hospital stay (14 vs 12 days) and noninfectious complications were decreased from 8% to 3%.

CONCLUSIONS

High-risk patients undergoing major operation for colorectal cancer profited from filgrastim prophylaxis with regard to duration of hospital stay, noninfectious complications, social QoL, and subjective recovery from operation. These endpoints, however, were secondary, and the primary endpoints (overall QoL and the McPeek index) did not show comparable benefits. A new confirmatory trial with the successful endpoints of this trial, as well as a cost analysis, will be needed to confirm the results before a general recommendation for the prophylactic use of G-CSF in high-risk cancer patients can be given.

Common infections in diabetes: pathogenesis, management and relationship to glycaemic control

Specific defects in innate and adaptive immune function have been identified in diabetic patients in a range of in vitro studies. However, the relevance of these findings to the integrated response to infection in vivo remains unclear, especially in patients with good glycaemic control. Vaccine efficacy seems adequate in most diabetic patients, but those with type 1 diabetes and high glycosylated haemoglobin levels are most likely to exhibit hypo-responsiveness. While particular infections are closely associated with diabetes, this is usually in the context of extreme metabolic disturbances such as ketoacidosis. The link between glycaemic control and the risk of common community-acquired infections is less well established but could be clarified if infection data from large community-based observational or intervention studies were available. The relationship between hospital-acquired infections and diabetes is well recognized, particularly among post-operative cardiac and critically ill surgical patients in whom intensive insulin therapy improves clinical outcome independent of glycaemia. Nevertheless, further research is needed to improve our understanding of the role of diabetes and glycaemic control in the pathogenesis and management of community- and hospital-acquired infections.

Optimising Antimicrobial Therapy in Diabetic Foot Infections

Foot infections are common and the most serious lower extremity complication contributing to amputations, particularly in patients with diabetes mellitus. Infection is most often a consequence of foot ulcerations, which typically follows trauma to a neuropathic foot. Foot infections may be classified as mild, moderate and severe; this largely determines the approach to therapy. Gram-positive bacteria are the sole causative pathogens for most mild and moderate infections. These infections can usually be treated with culture-based narrow-spectrum antibacterials along with appropriate surgical debridement in an outpatient setting. In contrast, severe infections are often polymicrobial, requiring hospitalisation and treatment with broad-spectrum antibacterials along with appropriate medical and surgical interventions. The initial empirical antibacterial regimen may be tailored based on the results of culture and sensitivity tests from properly obtained specimens. Several antibacterial regimens have demonstrated effectiveness in randomised controlled trials, but no single regimen has shown superiority. Managing diabetic foot osteomyelitis is particularly controversial and requires reliable cultures to select an appropriate antibacterial regimen. Surgical resection of the infected and necrotic bone favours a good outcome in chronic osteomyelitis. The recommended duration of antibacterial therapy ranges from 1 to 4 weeks for soft tissue infection, to >6 weeks for unresected osteomyelitis. The incidence of meticillin-resistant Staphylococcus aureus infection is increasing in both the healthcare setting and the community. This should be considered when selecting an antibacterial, especially if the patient does not improve with initial antibacterial therapy. Certain other organisms, such as Pseudomonas aeruginosa and Enterococcus spp., while potentially pathogenic, are often colonisers that do not require targeted therapy.

Topical granulocyte colony-stimulating factor for the treatment of oral and genital ulcers of patients with Behçet's disease

BACKGROUND

Recurrent and painful ulcers of the oral mucosa and genital skin/mucosa are the most commonly observed manifestations in patients with Behçet's disease (BD). They affect patients' quality of life. Because of the effectiveness of granulocyte colony-stimulating factor (G-CSF) in wound healing, it may also be useful for the treatment of oral ulcers (OU) and genital ulcers (GU) of BD.

OBJECTIVE

We aimed to determine the efficacy of topically applied G-CSF in the treatment of OU and GU of BD.

METHODS

Seven patients with BD diagnosed according to the criteria of the International Study Group for Behçet's Disease were involved in the study. The patients were observed for 3 months before the study, and all occurrences were recorded during this period. Patients were given topical G-CSF for OU (4 x 120 microg/day, for 5 days) and/or GU (4 x 30 microg/day, for 5 days) and followed-up for 3 months after treatment. No concurrent disease-specific or immunosuppressive topical or systemic drugs were given during the study period.

RESULTS

G-CSF treatment decreased the healing time and pain of OU and GU in six of seven patients compared with the pretreatment period. However, the effectiveness of the G-CSF treatment on OU and GU healing time and pain severity did not continue during the post-treatment period.

CONCLUSIONS

G-CSF has beneficial effects on the healing duration and pain severity of OU and GU of patients with BD. However, given the high cost, impractical preparation and inability to cure the disease, G-CSF treatment should be chosen only in selected patients.

Granulocyte colony-stimulating factor prophylaxis improves survival and inflammation in a two-hit model of hemorrhage and sepsis

OBJECTIVE

We evaluated the effects of a granulocyte-colony stimulating factor (G-CSF) prophylaxis in two clinically relevant situations, hemorrhage on the day before infection (e.g., trauma) and acute hemorrhage followed subsequently by infection (e.g., operative complication). A two-hit model of hemorrhage and polymicrobial peritoneal contamination and infection (PCI) was used to assess the influence of G-CSF on the outcome, bacterial clearance, and cytokine pattern.

DESIGN

Clinic modeling randomized laboratory trial.

SETTING

University laboratory.

SUBJECTS

One hundred thirty-two male rats.

INTERVENTIONS

In trial 1 we compared a) preoperative PCI only; b) preoperative hemorrhage plus PCI; and c) hemorrhage plus PCI plus G-CSF prophylaxis (n=18 rats/group). In trial 2, intraoperative hemorrhage was assessed with the same trial design. Primary end point was survival at 120 hrs. In trial 2 additionally, six rats per group and six naive control rats were used for secondary end point analysis.

MEASUREMENTS AND MAIN RESULTS

Primary end point was mortality at 120 hrs. Secondary end points were granulocyte counts, bacterial clearance, and local cytokine levels. In trial 1 survival rate was 56% after PCI only, 17% after hemorrhage plus PCI, and 61% after hemorrhage plus PCI plus G-CSF (p<.01). In trial 2 survival rate was 33% after PCI only, 17% after hemorrhage plus PCI, and 50% after hemorrhage plus PCI plus G-CSF (p<.05). In trial 2, neutrophil counts were doubled to 66% 1 hr after hemorrhage (p<.05), colony-forming units of microbes in the lung and liver were halved to 166+/-56 and 134+/-28 colony-forming units (p<.05 for liver), and the macrophage inflammatory protein-2 expression in the lung was halved to 0.88+/-0.06 pg of complementary DNA (p<.05) by G-CSF prophylaxis compared with hemorrhage and PCI.

CONCLUSIONS

Hemorrhage (first hit) sensitized the host for a second hit of polymicrobial PCI independent of the timing. G-CSF prophylaxis improved survival and clearance of microbes and reduced the proinflammatory chemokine macrophage inflammatory protein-2 in the lung.

Systematic review of antimicrobial treatments for diabetic foot ulcers

BACKGROUND

Foot ulcers in diabetes are associated with increased mortality, illness and reduced quality of life. Ulcer infection impairs healing and antimicrobial interventions may cure infection, aid healing and reduce amputation rates.

OBJECTIVES

To systematically review the evidence for antimicrobial interventions for foot ulcers in diabetes.

METHODS

We searched 16 databases, 11 Internet sites, three books, conference proceedings, a journal and bibliographies in November 2002. We included randomized controlled trials (RCTs) or controlled clinical trials (CCTs).

RESULTS

Twenty-three studies investigated the effectiveness or cost-effectiveness of antimicrobial agents: intravenous antibiotics (n = 8); oral antibiotics (n = 5); topical antimicrobials (n = 4); subcutaneous granulocyte-colony stimulating factor (G-CSF) (n = 4); Ayurvedic preparations (n = 1): and sugar vs. antibiotics vs. standard care (n = 1). The trials were small and too dissimilar to be pooled. There is no strong evidence for any particular antimicrobial agent for the prevention of amputation, resolution of infection, or ulcer healing. Pexiganan cream may be as effective as oral ofloxacin for resolution of infection. Ampicillin and sulbactam cost less than imipenem/cilastatin, G-CSF cost less than standard care and cadexomer iodine dressings may cost less than daily dressings.

CONCLUSIONS

The evidence is too weak to recommend any particular antimicrobial agent. Large studies are needed of the effectiveness and cost-effectiveness of antimicrobial interventions.

THE EFFECTS OF GRANULOCYTE COLONY-STIMULATING FACTOR IN PRECLINICAL MODELS OF INFECTION AND ACUTE INFLAMMATION

The cytokine granulocyte colony-stimulating factor (G-CSF) is a potent endogenous trigger for the release of neutrophils from bone marrow stores and for their activation for enhanced antimicrobial activity. G-CSF has been widely evaluated in preclinical models of acute illness, with generally promising though divergent results. A recombinant G-CSF molecule has recently undergone clinical trials to assess its efficacy as an adjuvant therapy in community-acquired and nosocomial pneumonia, however, these studies failed to provide convincing evidence of benefit. We undertook a systematic review of the published literature reporting the effects of modulation of G-CSF in preclinical in vivo models to determine whether evidence of differential efficacy might explain the disappointing results of human studies and point to disease states that might be more likely to benefit from G-CSF therapy. G-CSF has been evaluated in 86 such studies involving a variety of different models. The strongest evidence of benefit was seen in studies involving intraperitoneal challenge with live organisms; benefit was evident whether the agent was given before or after challenge. G-CSF demonstrates anti-inflammatory activity in models of systemic challenge with viable organisms or endotoxin, but only when the agent is given before challenge; evidence of benefit after challenge was minimal. Preclinical models of intrapulmonary challenge only show efficacy when the cytokine is administered before the infectious challenge, and suggested harm in gram-negative pneumonia resulting from challenge with Escherichia coli or Klebsiella. There is little evidence for therapeutic efficacy in noninfectious models of acute illness. We conclude that the most promising populations for evaluation of G-CSF are neutropenic patients with invasive infection and patients with intra-abdominal infection, particularly those with the syndrome of tertiary, or recurrent, peritonitis. Significant variability in the design and reporting of studies of preclinical models of acute illness precludes more sophisticated data synthesis.

A systematic approach to diabetic foot infections

Foot infection is the most common reason for hospitalization and subsequent lower extremity amputation among persons with diabetes. Foot ulceration caused by diabetic neuropathy, trauma, and peripheral vascular disease can lead to a limbor life-threatening infection. The optimum treatment of these potentially devastating conditions depends on a multidisciplinary approach that addresses the related or underlying disorders and thus ensures proper wound healing and a positive outcome. In addition to antibiotic therapy, severe soft-tissue or bone infections may necessitate surgical treatment, including drainage, débridement, and vascular reconstruction. Initial (empiric) antibiotic therapy should provide coverage against staphylococci and streptococci and should be revised according culture results. Antibiotic therapy is not indicated in clinically noninfected wounds. The duration of antibiotic treatment can range from 1 week for mild infections to 6 weeks or more for residual osteomyelitis and severe deep tissue infections. Aggressive (and sometimes repeated or staged) surgical intervention and appropriate antibiotic therapy can reduce the likelihood of a major amputation and the duration of hospitalization.

Are granulocyte colony-stimulating factors beneficial in treating diabetic foot infections?: A meta-analysis

OBJECTIVE

To assess the value of granulocyte colony-stimulating factor (G-CSF) as adjunctive therapy for diabetic foot infections.

RESEARCH DESIGN AND METHODS

We systematically searched the medical literature (including Medline, Embase, LookSmart, and the Cochrane Library) for prospective randomized studies that used G-CSF as an adjunct to standard treatment for diabetic foot infections. Using a conventional meta-analysis, we pooled the relative risks (RRs) for outcomes of interest, including resolution of infection, wound healing, duration of antibiotic therapy, and need for various surgical interventions, using a fixed-effects model.

RESULTS

Five randomized trials, with a total of 167 patients, met our inclusion criteria. The methodological quality of the studies was satisfactory. The investigators administered various G-CSF preparations parenterally for between 3 and 21 days. The meta-analysis revealed that adding G-CSF did not significantly affect the resolution of infection or the healing of the wounds but was associated with a significantly reduced likelihood of lower extremity surgical interventions (RR 0.38 [95% CI 0.20-0.69], number of patients who needed to be treated: 4.5), including amputation (0.41 [0.17-0.95], number of patients who needed to be treated: 8.6). There was no evidence of heterogeneity among the studies or of publication bias, suggesting that these conclusions are reasonably generalizable and robust.

CONCLUSIONS

Adjunctive G-CSF treatment does not appear to hasten the clinical resolution of diabetic foot infection or ulceration but is associated with a reduced rate of amputation and other surgical procedures. The small number of patients who needed to be treated to gain these benefits suggests that using G-CSF should be considered, especially in patients with limb-threatening infections.

New and experimental approaches to treatment of diabetic foot ulcers: a comprehensive review of emerging treatment strategies

Diabetic foot ulcers occur in up to 15% of all diabetic patients and are a leading cause of nontraumatic amputation worldwide. Neuropathy, abnormal foot biomechanics, peripheral vascular disease and external trauma are the major contributors to the development of a foot ulcer in the diabetic patient. Therapy today includes repeated debridement, offloading, and dressings, for lower grade ulcers, and broad spectrum antibiotics and occasionally limited or complete amputation for higher grades, requiring a team effort of health care workers from various specialties. The large population affected by diabetic foot ulcers and the high rates of failure ending with amputation even with the best therapeutic regimens, have resulted in the development of new therapies and are the focus of this review. These include new off loading techniques, dressings from various materials, methods to promote wound closure using artificial skin grafts, different growth factors or wound bed modulators and methods of debridement. These new techniques are promising but still mostly unproven and traditional approaches cannot be replaced. New and generally more expensive therapies should be seen as adding to traditional approaches.

Adjunctive Granulocyte Colony-Stimulating Factor Therapy for Diabetic Foot Infections

OBJECTIVE

To evaluate the role of granulocyte colony-stimulating factor (G-CSF) as adjunctive therapy for the treatment of diabetic foot infections in non-neutropenic patients.

DATA SOURCES

Clinical literature was accessed through MEDLINE (1965–April 2004). Key search terms included G-CSF, infection, and diabetes. In addition, relevant references from primary and secondary article bibliographies were extracted.

DATA SYNTHESIS

Three clinical trials evaluating G-CSF for diabetic foot infections were identified. These data demonstrated positive effects of G-CSF on improvement of foot infections and risk of amputations.

CONCLUSIONS

Controlled trials are necessary to validate the role of adjunctive G-CSF at reducing amputations in patients with diabetic foot infections.

Is there a place for granulocyte colony-stimulating factor in non-neutropenic critically ill patients?

Immunoparalysis, characterised by impairments in neutrophil and monocyte/macrophage function, is common in critically ill patients. The theoretical ability of granulocyte colony-stimulating factor (G-CSF) to improve the functions of both neutrophils and monocytes/macrophages provides a rationale for G-CSF therapy in non-neutropenic critically ill patients with infection or a high risk of nosocomial infection. The expression of the receptors that mediate G-CSF effects in neutrophils and monocytes/macrophages is regulated by bacterial products, cytokines and endogenous G-CSF levels, accounting for the variables effects of G-CSF on the neutrophil functions of critically ill patients. This variability should be taken into account when designing studies on the use of G-CSF in ICU-patients. Studies are still needed to identify the subset of patients who may benefit from G-CSF therapy.

Diabetic foot ulcers

Ulceration of the foot in diabetes is common and disabling and frequently leads to amputation of the leg. Mortality is high and healed ulcers often recur. The pathogenesis of foot ulceration is complex, clinical presentation variable, and management requires early expert assessment. Interventions should be directed at infection, peripheral ischaemia, and abnormal pressure loading caused by peripheral neuropathy and limited joint mobility. Despite treatment, ulcers readily become chronic wounds. Diabetic foot ulcers have been neglected in health-care research and planning, and clinical practice is based more on opinion than scientific fact. Furthermore, the pathological processes are poorly understood and poorly taught and communication between the many specialties involved is disjointed and insensitive to the needs of patients.

Growth factors in the treatment of diabetic foot ulcers

BACKGROUND

Chronic foot ulceration is a major source of morbidity in diabetic patients. Despite traditional comprehensive wound management, including vascular reconstruction, there remains a cohort of patients with non-responding wounds, often resulting in amputation. These wounds may benefit from molecular manipulation of growth factors to enhance the microcirculation.

METHODS

A review of the current literature was performed using Pubmed, with secondary references obtained from key articles.

RESULTS AND CONCLUSION

There has been a generally disappointing clinical outcome from growth factor trials, although topical platelet-derived growth factor has shown significant benefit and should be considered in non-healing, well perfused ulcers after failure of conventional wound care. The modulatory role of the extracellular matrix in the cellular response to growth factors and data from regenerative-type fetal wound healing are further areas of interest. The chemical induction of microvessel formation may become a future therapeutic option.

Induction and regulation of endogenous granulocyte colony-stimulating factor formation

Granulocyte colony-stimulating factor (G-CSF) is one of the most prominent endogenous proteins in broad clinical use. While its biological and clinical effects are relatively well studied, little is known about its endogenous formation in health and disease. However, such knowledge is crucial to decide in which situations G-CSF should be applied efficiently in the clinic, ie. when endogenous production does not suffice. The dramatic changes induced by G-CSF in the differential blood cell count are directly immunomodulatory, strengthening the innate defence by multiplying neutrophilic granulocytes. A multitude of further immunomodulatory effects contribute to the regulation of the concerted host defence. In this review, following a short introduction into the biology of G-CSF, the available data on endogenous formation in a number of animal models and human diseases is compiled. The cellular sources and inducers of G-CSF formation are reviewed and the regulation of G-CSF expression on both the transcriptional and translational level are discussed. The emerging understanding of the role and regulation of endogenous G-CSF formation opens up possibilities to define therapeutic windows as well as targets for diagnostics or drug development. Lastly, the modulation of G-CSF formation by various pharmacological agents alerts to putative side effects of these drug treatments.