Influence of Skin Commensals on Therapeutic Outcomes of Surgically Debrided Diabetic Foot Infections-A Large Retrospective Comparative Study

In diabetic foot infections (DFI), the clinical virulence of skin commensals are generally presumed to be low. In this single-center study, we divided the wound isolates into two groups: skin commensals (coagulase-negative staphylococci, micrococci, corynebacteria, cutibacteria) and pathogenic pathogens, and followed the patients for ≥ 6 months. In this retrospective study among 1018 DFI episodes (392 [39%] with osteomyelitis), we identified skin commensals as the sole culture isolates (without accompanying pathogenic pathogens) in 54 cases (5%). After treatment (antibiotic therapy [median of 20 days], hyperbaric oxygen in 98 cases [10%]), 251 episodes (25%) were clinical failures. Group comparisons between those growing only skin commensals and controls found no difference in clinical failure (17% vs. 24 %, p = 0.23) or microbiological recurrence (11% vs. 17 %, p = 0.23). The skin commensals were mostly treated with non-beta-lactam oral antibiotics. In multivariate logistic regression analysis, the isolation of only skin commensals was not associated with failure (odds ratio 0.4, 95% confidence interval 0.1-3.8). Clinicians might wish to consider these isolates as potential pathogens when selecting a targeted antibiotic regimen, which may also be based on oral non-beta-lactam antibiotic agents effective against the corresponding skin pathogens

Pseudomonal Diabetic Foot Infections: Vive la Différence?

Objective To assess the outcomes of diabetic foot infections (DFIs) due to Pseudomonas aeruginosa. Patients and Methods From April 24, 2013 to July 31, 2016, we analyzed data from patients prospectively enrolled in our clinical pathway of DFIs, comparing those with infection due to Pseudomonas with those without infection due to Pseudomonas. Results Overall, we assessed 1018 cases of DFIs: 392 with osteomyelitis and 626 with only soft tissue infections. The prevalence of P aeruginosa in deep wound cultures was 10% (104/1018); of the 1018 cultures, 22 were monomicrobial, 82 were polymicrobial, and 46 were with osteomyelitis. Overall, the patients were treated with a median of 1 surgical debridement and a total of 20 days of antibiotic therapy. In a comparison of crude groups, the proportion of clinical failures was significantly higher with Pseudomonas than with other pathogens (36/104 [35%] vs 218/914 [24%], respectively; P=.02). A multivariate analysis showed that pseudomonal DFIs did not recur more often than nonpseudomonal DFIs (hazard ratio, 1.0; 95% confidence interval, 0.6-1.7). Among the 104 cases of pseudomonal DFIs, there was no association between failure of treatment and the total duration of antibiotic therapy, duration of intravenous therapy, duration of combined antibiotic therapy with more than 1 agent, or duration of oral (fluoroquinolone) therapy. Among 15 cases of pseudomonal recurrence, 2 (13%) developed resistance to the antibiotic agent used for the index episode. Conclusion For DFIs caused by P aeruginosa, other than choosing an antibiotic agent that is active against the organism, it does not appear necessary to treat with a different therapeutic regimen compared with the treatment of nonpseudomonal DFIs. There is no difference

Urinary Catheters: What Type Do Men and Their Nurses Prefer?

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/111067/1/j.1532-5415.1999.tb01567.x.pd

Developing and Validating a Risk Score for Lower-Extremity Amputation in Patients Hospitalized for a Diabetic Foot Infection

Objective: Diabetic foot infection is the predominant predisposing factor to nontraumatic lower-extremity amputation (LEA), but few studies have investigated which specific risk factors are most associated with LEA. We sought to develop and validate a risk score to aid in the early identification of patients hospitalized for diabetic foot infection who are at highest risk of LEA. Research Design and Methods: Using a large, clinical research database (CareFusion), we identified patients hospitalized at 97 hospitals in the U.S. between 2003 and 2007 for culture-documented diabetic foot infection. Candidate risk factors for LEA included demographic data, clinical presentation, chronic diseases, and recent previous hospitalization. We fit a logistic regression model using 75% of the population and converted the model coefficients to a numeric risk score. We then validated the score using the remaining 25% of patients. Results: Among 3,018 eligible patients, 21.4% underwent an LEA. The risk factors most highly associated with LEA (P 11,000 per mm3. The model showed good discrimination (c-statistic 0.76) and excellent calibration (Hosmer-Lemeshow, P = 0.63). The risk score stratified patients into five groups, demonstrating a graded relation to LEA risk (P < 0.0001). The LEA rates (derivation and validation cohorts) were 0% for patients with a score of 0 and ~50% for those with a score of ≥21. Conclusions: Using a large, hospitalized population, we developed and validated a risk score that seems to accurately stratify the risk of LEA among patients hospitalized for a diabetic foot infection. This score may help to identify high-risk patients upon admission

Moderate to Severe Soft Tissue Diabetic Foot Infections: A Randomized, Controlled, Pilot Trial of Post-Debridement Antibiotic Treatment for 10 versus 20 days

Background: The optimal duration of antibiotic therapy for soft-tissue infections of the diabetic foot (ST-DFI) remains unknown. Objective: We determine if antibiotic therapy after debridement for a short (10 days), compared with a long (20 days), duration for ST-DFI results in similar rates of clinical remission and adverse events (AE). Summary Background Data: The optimal duration of systemic antibiotic therapy, after successful debridement, for soft tissue infections of diabetic patients is unknown. Because of the high recurrence risk, overuse is commonplace. Methods: This was a randomized, controlled, non-inferiority pilot trial of cases of diabetic foot infection (excluding osteomyelitis) with the primary outcome of “clinical remission at two-months follow-up”. Results: Among 66 enrolled episodes (17% females; median age 71 years), we randomized 35 to the 10-day arm and 31 to the 20-day arm. The median duration of the parenteral antibiotic therapy was 1 day, with the remainder given orally. In the intention-to-treat (ITT) population, we achieved clinical remission in 27 (77%) patients in the 10-day arm compared to 22 (71%) in the 20-days arm (p = 0.57). There were a similar proportion in each arm of AE (14/35 versus 11/31; p = 0.71), and remission in the per-protocol (PP) population (25/32 vs. 18/27; p = 0.32). Overall, eight soft tissue DFIs in the 10-day arm and five cases in the 20-day arm recurred as a new osteomyelitis (8/35 [23%] versus 5/31 [16%]; p = 0.53). Overall, the number of recurrences limited to the soft tissues was 4 (6%). By multivariate analysis, rates of remission (ITT population, hazard ratio 0.6, 95%CI 0.3-1.1; PP population 0.8, 95%CI 0.4-1.5) and AE were not significantly different with a 10-day compared to 20-day course. Conclusions: In this randomized, controlled pilot trial, post-debridement antibiotic therapy for soft tissue DFI for 10 days gave similar (and non-inferior) rates of remission and AEs to 20 days. A larger confirmatory trial is under way

Timing of Revascularization and Parenteral Antibiotic Treatment Associated with Therapeutic Failures in Ischemic Diabetic Foot Infections

For ischemic diabetic foot infections (DFIs), revascularization ideally occurs before surgery, while a parenteral antibiotic treatment could be more efficacious than oral agents. In our tertiary center, we investigated the effects of the sequence between revascularization and surgery (emphasizing the perioperative period of 2 weeks before and after surgery), and the influence of administering parenteral antibiotic therapy on the outcomes of DFIs. Among 838 ischemic DFIs with moderate-to-severe symptomatic peripheral arterial disease, we revascularized 608 (72%; 562 angioplasties, 62 vascular surgeries) and surgically debrided all. The median length of postsurgical antibiotic therapy was 21 days (given parenterally for the initial 7 days). The median time delay between revascularization and debridement surgery was 7 days. During the long-term follow-up, treatment failed and required reoperation in 182 DFI episodes (30%). By multivariate Cox regression analyses, neither a delay between surgery and angioplasty (hazard ratio 1.0, 95% confidence interval 1.0-1.0), nor the postsurgical sequence of angioplasty (HR 0.9, 95% CI 0.5-1.8), nor long-duration parenteral antibiotic therapy (HR 1.0, 95% CI 0.9-1.1) prevented failures. Our results might indicate the feasibility of a more practical approach to ischemic DFIs in terms of timing of vascularization and more oral antibiotic use

Standards for the development and methodology of the 2019 International Working Group on the Diabetic Foot guidelines

Diabetic foot disease is a source of major patient suffering and societal costs. Investing in evidence-based international guidelines on diabetic foot disease is likely among the most cost-effective forms of health care expenditure, provided the guidelines are outcome focused, evidence based, and properly implemented. The International Working Group on the Diabetic Foot (IWGDF) has published and updated international guidelines since 1999. The 2019 updates are based on formulating relevant clinical questions and outcomes, rigorous systematic reviews of the literature, and recommendations that are specific, and unambiguous along with their transparent rationale, all using the Grading of Recommendations Assessment Development and Evaluation (GRADE) framework. We herein describe the development of the 2019 IWGDF guidelines on the prevention and management of diabetic foot disease, which consists of six chapters, each prepared by a separate working group of international experts. These documents provide guidelines related to diabetic foot disease on prevention; offloading; peripheral artery disease; infection; wound healing interventions; and classification of diabetic foot ulcers. Based on these six chapters, the IWGDF Editorial Board also produced a set of practical guidelines. Each guideline underwent extensive review by the members of the IWGDF Editorial Board as well as independent international experts in each field. We believe that adoption and implementation of the 2019 IWGDF guidelines by health care providers, public health agencies, and policymakers will result in improved prevention and management of diabetic foot disease and a subsequent worldwide reduction in the patient and societal burden this disease causes

Initial antibiotic therapy for postoperative moderate or severe diabetic foot infections: Broad versus narrow spectrum, empirical versus targeted

AIM To retrospectively evaluate clinical and microbiological outcomes after combined surgical and medical therapy for diabetic foot infections (DFIs), stratifying between the empirical versus the targeted nature, and between an empirical broad versus a narrow-spectrum, antibiotic therapy. METHODS We retrospectively assessed the rate of ultimate therapeutic failures for each of three types of initial postoperative antibiotic therapy: adequate empirical therapy; culture-guided therapy; and empirical inadequate therapy with a switch to targeted treatment based on available microbiological results. RESULTS We included data from 332 patients who underwent 716 DFI episodes of surgical debridement, including partial amputations. Clinical failure occurred in 40 of 194 (20.6%) episodes where adequate empirical therapy was given, in 77 of 291 (26.5%) episodes using culture-guided (and correct) therapy from the start, and in 73 of 231 (31.6%) episodes with switching from empirical inadequate therapy to culture-targeted therapy. Equally, a broad-spectrum antibiotic choice could not alter this failure risk. Group comparisons, Kaplan-Meier curves and Cox regression analyses failed to show either statistical superiority or inferiority of any of the initial antibiotic strategies. CONCLUSIONS In this study, the microbiological adequacy of the initial antibiotic regimen after (surgical) debridement for DFI did not alter therapeutic outcomes. We recommend that clinicians follow the stewardship approach of avoiding antibiotic de-escalation and start with a narrow-spectrum regimen based on the local epidemiology

CODIFI (Concordance in Diabetic Foot Ulcer Infection) : a cross-sectional study of wound swab versus tissue sampling in infected diabetic foot ulcers in England

OBJECTIVE: To determine the extent of agreement and patterns of disagreement between wound swab and tissue samples in patients with an infected diabetic foot ulcer (DFU). DESIGN: Multicentre, prospective, cross-sectional study. SETTING: Primary and secondary care foot ulcer/diabetic outpatient clinics and hospital wards across England. PARTICIPANTS: Inclusion criteria: consenting patients aged ≥18 years; diabetes mellitus; suspected infected DFU. EXCLUSION CRITERIA: clinically inappropriate to take either sample. INTERVENTIONS: Wound swab obtained using Levine's technique; tissue samples collected using a sterile dermal curette or scalpel. OUTCOME MEASURES: Coprimary: reported presence, and number, of pathogens per sample; prevalence of resistance to antimicrobials among likely pathogens. Secondary: recommended change in antibiotic therapy based on blinded clinical review; adverse events; sampling costs. RESULTS: 400 consenting patients (79% male) from 25 centres.Most prevalent reported pathogens were Staphylococcus aureus (43.8%), Streptococcus (16.7%) and other aerobic Gram-positive cocci (70.6%). At least one potential pathogen was reported from 70.1% of wound swab and 86.1% of tissue samples. Pathogen results differed between sampling methods in 58% of patients, with more pathogens and fewer contaminants reported from tissue specimens.The majority of pathogens were reported significantly more frequently in tissue than wound swab samples (P<0.01), with equal disagreement for S. aureus and Pseudomonas aeruginosa. Blinded clinicians more often recommended a change in antibiotic regimen based on tissue compared with wound swab results (increase of 8.9%, 95% CI 2.65% to 15.3%). Ulcer pain and bleeding occurred more often after tissue collection versus wound swabs (pain: 9.3%, 1.3%; bleeding: 6.8%, 1.5%, respectively). CONCLUSION: Reports of tissue samples more frequently identified pathogens, and less frequently identified non-pathogens compared with wound swab samples. Blinded clinicians more often recommended changes in antibiotic therapy based on tissue compared with wound swab specimens. Further research is needed to determine the effect of the additional information provided by tissue samples. TRIAL REGISTRATION NUMBER: ISRCTN52608451