Diabetic foot infection: Antibiotic therapy and good practice recommendations.

BACKGROUND: Healthcare events related to diabetic foot disease carry a burden of morbidity, mortality and economic cost. Prompt identification of clinical infection with appropriate tissue sampling limits use of broad spectrum empirical antibiotics and improves antibiotic stewardship. Staphylococcus aureus remains the commonest infecting organism and high-dose flucloxacillin remains the empirical antibiotic of choice for antibiotic naïve patients. Barriers to microbe-specific treatment include: adequate tissue sampling, delays in culture results, drug allergies and the emergence of multidrug-resistant organisms which can complicate the choice of targeted antibiotics. Even appropriate antibiotic treatment carries a risk of adverse events including the selection of resistant organisms. AIMS: Multidisciplinary clinical assessment of a diabetic foot infection is supported by the use of appropriate imaging modalities and deep tissue sampling, both of which are encouraged to enhance sampling accuracy. Narrow-spectrum, high dose, short duration antimicrobial therapy is ideal. Further clarity in these areas would be of benefit to clinicians involved in management of diabetic foot infections. METHODS: A combination of literature review with expert discussion was used to generate consensus on management of diabetic foot infection, with a specific focus on empirical antimicrobial therapy. RESULTS: Gram positive organisms represent the commonest pathogens in diabetic foot infection. However there are developing challenges in antimicrobial resistance and antibiotic availability. DISCUSSION: Recommendations for empirical therapy, including the choice of alternative oral agents and use of outpatient antibiotics would be of benefit to those involved in diabetic foot care. CONCLUSION: This paper provides advice on empirical antibiotic therapy that may be used as a framework for local guideline development to support clinicians in the management of diabetic foot infection.

Human Subcutaneous Adipose Tissue Sampling using a Mini-liposuction Technique.

Studies on adipose tissue are useful in understanding metabolic and other conditions. Human subcutaneous adipose tissue is accessible. With appropriate training and strict adherence to aseptic technique, subcutaneous adipose samples can be safely and efficiently obtained in a non-clinical setting by researchers. Following the administration of local anesthetic lateral to the umbilicus, a 14 G needle attached to a 5 or 10 mL syringe is inserted through the skin into the subcutaneous tissue. Under suction, the syringe is moved in a reciprocating, slicing motion to isolate fragments of adipose tissue. Withdrawing the plunger is enough to ensure that adipose tissue fragments are aspirated through the needle into the syringe. A single biopsy can collect about 200 mg of tissue. This biopsy technique is very safe for both participants and research staff. Following the biopsy, participants can resume most everyday activities, although they should avoid swimming and overly strenuous activities for 48 h to avoid excessive bleeding. Participants can safely undergo 2 biopsies within a single day, meaning that the technique can be applied in before-after acute intervention studies.

Effects of diabetes family history and exercise training on the expression of adiponectin and leptin and their receptors.

Daughters of diabetes patients have lower insulin sensitivity than women with no diabetes family history, but increase insulin sensitivity to a greater extent with exercise training. This study aimed to determine whether differences in circulating concentrations of adiponectin and leptin, and adipose tissue expression of their genes and receptors played a role. Women offspring of patients with type 2 diabetes mellitus (n = 34; age, 35.6 ± 7.0 years; body mass index, 28.1 ± 5.1 kg/m²) and matched controls with no diabetes family history (n = 36; age, 33.6 ± 6.1 years; body mass index, 27.3 ± 4.7 kg/m²) participated. Blood and abdominal subcutaneous adipose tissue samples were obtained at baseline and after a controlled 7-week endurance-type exercise intervention (sessions were performed at 65%-80% of maximum heart rate). At baseline, no significant differences were observed between groups in circulating leptin or adiponectin concentrations, or expression of their genes or receptors. In response to exercise, plasma leptin decreased more in offspring than controls (-32.2% vs -7.3%, P = .005 for interaction); and the long isoform of the leptin receptor messenger RNA (mRNA) increased significantly only in the offspring (+39.4%, P = .026 vs +7.7%, P = .892). Leptin mRNA decreased similarly in both groups (-24.7% vs -25.0%, P < .05 for both). Furthermore, changes in plasma leptin (r = -0.432, P < .001) and leptin mRNA (r = -0.298, P = .019) correlated significantly with changes in insulin sensitivity. Plasma adiponectin decreased similarly in both groups (-12.1% vs -15.2%, P < .01 for both), but no significant changes were observed in adiponectin-related gene expression. This work shows that exercise training has differing effects on leptin-related variables between women with and without a diabetes family history and suggests that these molecular differences may contribute to the differential effects of exercise training on insulin sensitivity between these 2 groups.

Individual responsiveness to exercise-induced fat loss is associated with change in resting substrate utilization.

Fat loss in response to exercise training varies between individuals, even when differences in compliance to the exercise program are accounted for. The purpose of this study was to investigate whether individual variation in change in fasting respiratory quotient (RQ) after exercise training contributes to this interindividual variability. Fifty-five premenopausal women participated in a 7-week endurance-type exercise training program; and fitness, body composition, and resting substrate utilization and metabolic rate in the fasted state were assessed at baseline and postintervention. Total net energy expenditure of the exercise intervention (exEE) was determined from heart rate obtained in all exercise sessions and individualized calibration of the heart rate vs oxygen uptake relationship. Dietary intake and physical activity (by constant heart rate monitoring) were assessed at baseline and during the final week of the intervention. Mean change in fat mass for the group was -0.97 kg (range, +2.1 to -5.3 kg). The strongest correlate of change in fat mass was exEE (r = 0.60, P < .0005). Change in fasting RQ correlated significantly (r = -0.26, P = .05) with the residual for change in fat mass after adjusting for the effects of both exEE and change in energy intake, explaining 7% of the variance. In multiple regression analysis, exEE (P < .0005) and change in fasting RQ (P = .02) were the only statistically significant independent predictors of change in fat mass, together explaining 40.2% of the variance. Thus, fat loss in response to exercise training depends not only on exercise energy expenditure but also on exercise training-induced changes in RQ at rest. This suggests that development of strategies to maximize the change in resting fat oxidation in response to an exercise training program may help individuals to maximize exercise-induced fat loss.