Screening patients at risk for diabetic foot ulceration: a comparison between measurement of vibration perception threshold and 10-g monofilament test.

The aim is to compare the frequency of increased vibration perception threshold (VPT) with abnormal 10-g Semmes-Weinstein monofilament (SWF) testing in a non-selected diabetic population, and to assess the agreement between these two screening methods. VPT was measured using a neurothesiometer at the pulp of the hallux and 10-g SWF was applied on three plantar sites on each foot according to the guidelines of the International Working Group on the Diabetic Foot, in 400 consecutive diabetic patients. VPT was considered as abnormal if ≥25 V and SWF was considered as abnormal if the patient was unable to feel ≥2 applications at a single site. Both tests were normal in 240 patients (60%) and both abnormal in 78. In 21 patients, only SWF was abnormal whereas only VPT was abnormal in 61. As a whole, 160 patients (40%) were considered at risk for foot ulceration by VPT and/or SWF. Agreement between the two screening methods was only moderate with a kappa coefficient of 0·52 (95% CI: 0·43-0·60). Using VPT as a predictor for foot ulceration, the number of patients at risk is much higher than identified by SWF. This discrepancy might have potential effects on costs and prevention policies.

Diabetes and foot infection: more than double trouble.

BACKGROUND: Infection of foot ulcers is a common, often severe and costly complication in diabetes. Many factors linked to the host, mainly immune defects, neuropathy and arteriopathy, as well as bacteria-related factors, interact in a complex way and account for the susceptibility of diabetic individuals to foot infections, the severity of such infections and difficulty to treat them. METHODS: This article reviews these factors, in the light of data from the literature and from our own results. RESULTS: DFIs are not as simple as previously suggested, and new concepts must be considered, especially the virulence potential of isolates and bacterial communications through biofilms. CONCLUSION: The development of new tools from molecular biology is a critical step to better understand and manage these infections.

Economic evaluation of Vacuum Assisted Closure® Therapy for the treatment of diabetic foot ulcers in France.

The objective of the study was to assess the cost-effectiveness of Vacuum Assisted Closure® (V.A.C.®) Therapy compared with advanced wound care (AWC) for the treatment of diabetic foot ulcers (DFUs) in France. A cost-effectiveness model intended to reflect the management of DFUs was updated for the French setting. The Markov model follows the progression of 1000 hypothetical patients over a 1-year period. The model was populated with French-specific data, obtained from published sources and clinical experts. The analysis evaluated costs and health outcomes, in terms of quality-adjusted life-years (QALYs), wounds healed and amputations, from the perspective of the payer. The patients treated with V.A.C.® Therapy experienced more QALYs (0.787 versus 0.784) and improved healing rates (50.2% versus 48.5%) at a lower total cost of care (€24,881 versus €28,855 per patient per year) when compared with AWC. Sensitivity analyses conducted around key model parameters indicated that the results were affected by hospital resource use and costs. DFU treatment using V.A.C.® Therapy in France was associated with lower costs, additional QALYs, more healed ulcers and fewer amputations than treatment with AWC. V.A.C.® Therapy was therefore found to be the dominant treatment option.

Dressings for acute and chronic wounds: a systematic review.

OBJECTIVE: To critically review the literature on the efficacy of modern dressings in healing chronic and acute wounds by secondary intention. DATA SOURCES: Search of 3 databases (MEDLINE, EMBASE, and the Cochrane Controlled Clinical Trials Register) from January 1990 to June 2006, completed by manual research, for articles in English and in French. STUDY SELECTION: The end points for selecting studies were the rate of complete healing, time to complete healing, rate of change in wound area, and general performance criteria (eg, pain, ease of use, avoidance of wound trauma on dressing removal, ability to absorb and contain exudates). Studies were selected by a single reviewer. Overall, 99 studies met the selection criteria (89 randomized controlled trials [RCTs], 3 meta-analyses [1 of which came from 1 of the selected systematic reviews], 7 systematic reviews, and 1 cost-effectiveness study). DATA EXTRACTION: The RCTs, meta-analyses, and cost-effectiveness studies were critically appraised by 2 reviewers to assess the clinical evidence level according to a modification of Sackett's 1989 criteria. Ninety-three articles were finally graded. DATA SYNTHESIS: We found no level A studies, 14 level B studies (11 RCTs and 3 meta-analyses), and 79 level C studies. Hydrocolloid dressings proved superior to saline gauze or paraffin gauze dressings for the complete healing of chronic wounds, and alginates were better than other modern dressings for debriding necrotic wounds. Hydrofiber and foam dressings, when compared with other traditional dressings or a silver-coated dressing, respectively, reduced time to healing of acute wounds. CONCLUSIONS: Our systematic review provided only weak levels of evidence on the clinical efficacy of modern dressings compared with saline or paraffin gauze in terms of healing, with the exception of hydrocolloids. There was no evidence that any of the modern dressings was better than another, or better than saline or paraffin gauze, in terms of general performance criteria. More wound care research providing level A evidence is needed.

A multicenter, double-blind, safety study of QR-333 for the treatment of symptomatic diabetic peripheral neuropathy. A preliminary report.

BACKGROUND: QR-333, a topical compound that contains quercetin, a flavonoid with aldose reductase inhibitor effects, ascorbyl palmitate, and vitamin D(3), was formulated to decrease the oxidative stress that contributes to peripheral diabetic neuropathy and thus alleviate its symptoms. This proof-of-principle study assessed the efficacy and safety of QR-333 against placebo in a small cohort of patients with diabetic neuropathy. METHODS: This randomized, placebo-controlled, double-blind trial included 34 men and women (21-71 years of age) with Type 1 or 2 diabetes and diabetic neuropathy who applied QR-333 or placebo (2:1 ratio), three times daily for 4 weeks, to each foot where symptoms were experienced. Five-point scales were used to determine changes from baseline to endpoint in symptoms and quality of life (efficacy). Safety was assessed through concomitant medications, adverse events, laboratory evaluations, and physical examinations. RESULTS: QR-333 reduced the severity of numbness, jolting pain, and irritation from baseline values. Improvements were also seen in overall and specific quality-of-life measures. QR-333 was well tolerated. Eleven patients in the QR-333 group reported 23 adverse events (all mild or moderate); 4 in the placebo group reported 5 events (all moderate). One patient who applied QR-333 noted a pricking sensation twice, the only adverse event considered possibly related to study treatment. CONCLUSIONS: From this preliminary safety study, it appears that QR-333 may safely offer relief of symptoms of diabetic neuropathy and improve quality of life. These findings warrant further investigation of this topical compound.

Distinguishing colonization from infection with Staphylococcus aureus in diabetic foot ulcers with miniaturized oligonucleotide arrays: a French multicenter study.

OBJECTIVE: To extend our previous work on evaluating the use of oligonucleotide arrays to discriminate colonization from infection owing to Staphylococcus aureus in diabetic foot ulcers (DFUs). RESEARCH DESIGN AND METHODS: Patients admitted to 14 French diabetic foot departments for a DFU were screened for entry into the study. At admission, ulcers were classified based on clinical examination according to the Infectious Diseases Society of America system. Only patients with monomicrobial culture for S. aureus were included. In persons with an uninfected ulcer, a second wound bacterial specimen was obtained 1 month later. Using oligonucleotide arrays, S. aureus resistance and virulence genes were determined, and each isolate was affiliated to a clonal complex (CC). RESULTS: S. aureus was initially isolated from 75 uninfected and 120 infected ulcers; 35 were methicillin resistant. A total of 44 (59%) strains from uninfected DFUs belonged to CC5/CC8 clones vs. 6 (5%) from infected DFUs (P < 0.001). During follow-up, 57 (76%) of uninfected DFUs healed or had a favorable outcome; the strain in 49 (86%) of them belonged to CC5/CC8. Conversely, 18 (24%) had a poor outcome but not a single strain belonged to CC5/CC8 clone. Moreover, lukDE was significantly associated with a favorable outcome of the wound. CONCLUSIONS: As suggested by our previous study, the use of DNA arrays appears to be a promising technique that might help distinguishing uninfected from infected wounds, predicting ulcer outcome and then contributing to a more adequate use of antibiotics.

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.

Virulence potential of Staphylococcus aureus strains isolated from diabetic foot ulcers: a new paradigm.

OBJECTIVE: The purpose of this study was to assess the virulence potential of Staphylococcus aureus strains isolated from diabetic foot ulcers and to discriminate noninfected from infected ulcers. RESEARCH DESIGN AND METHODS: Diabetic patients hospitalized in a diabetic foot department with a foot ulcer were prospectively enrolled if they had been free of antibiotic treatment over the previous 6 months. At admission, ulcers were classified as infected or noninfected on the basis of clinical examination, according to the International Working Group on the Diabetic Foot system. Only patients carrying S. aureus as the sole pathogen were included. In individuals with a grade 1 ulcer, a second bacterial specimen was obtained 1 month later. Using virulence genotyping markers, clonality tools, and an in vivo Caenorhabditis elegans model, we correlated the virulence of 132 S. aureus strains with grade, time of collection, and ulcer outcome. RESULTS: Among virulence genes, the most relevant combination derived from the logistic regression was the association of cap8, sea, sei, lukE, and hlgv (area under the curve 0.958). These markers were useful to distinguish noninfected (grade 1) from infected (grades 2-4) ulcers and to predict wound status at the follow-up. With use of the nematode model, S. aureus strains isolated from grade 1 ulcers were found to be significantly less virulent than strains from ulcers at or above grade 2 (P < 0.001). CONCLUSIONS: This study highlights the coexistence of two S. aureus populations on diabetic foot ulcers. A combination of five genes that may help distinguish colonized grade 1 from infected grade >or=2 wounds, predict ulcer outcome, and contribute to more appropriate use of antibiotics was discovered.

Miniaturized oligonucleotide arrays: a new tool for discriminating colonization from infection due to Staphylococcus aureus in diabetic foot ulcers.

OBJECTIVE: We sought to evaluate the use of oligonucleotide arrays to discriminate colonization from infection due to Staphylococcus aureus in diabetic foot ulcers. RESEARCH DESIGN AND METHODS: We included diabetic patients hospitalized in a diabetic foot department for an episode of foot ulcer. Only patients who had no antibiotic treatment during the previous 6 months were included. At admission, ulcers were classified on clinical examination, according to the Infectious Diseases Society of America system. Seventy-two patients with a culture positive only for S. aureus as the sole pathogen were included. In individuals with a grade 1 ulcer, a second wound bacterial specimen was obtained 1 month later. Using oligonucleotide arrays, S. aureus resistance and virulence genes were compared between grade 1 and grades 2-4 ulcers. RESULTS: S. aureus was initially isolated from 22 grade 1 and 50 grade 2-4 ulcers: 35 were methicillin resistant and 37 methicillin sensitive. In 20 grade 1 ulcers (92%), no virulence genes were identified, whereas these genes were present in all but 1 grade 2-4 ulcers. During follow-up, the two grade 1 ulcers that were infected with strains carrying virulence genes rapidly deteriorated; the array technology showed unchanged genotype profiles. On the contrary, two grade 1 ulcers healed: the genotype profiles were different from those at inclusion but without appearance of virulence genes. CONCLUSIONS: The DNA array appears as a promising technique and is easy to perform. Our observational study suggests that it might help distinguish colonized grade 1 from infected grade 2 wounds, predict ulcer outcome, and contribute to a more adequate use of antibiotics.