Subpopulations in Strains of Staphylococcus aureus Provide Antibiotic Tolerance

The ability of Staphylococcus aureus to colonise different niches across the human body is linked to an adaptable metabolic capability, as well as its ability to persist within specific tissues despite adverse conditions. In many cases, as S. aureus proliferates within an anatomical niche, there is an associated pathology. The immune response, together with medical interventions such as antibiotics, often removes the S. aureus cells that are causing this disease. However, a common issue in S. aureus infections is a relapse of disease. Within infected tissue, S. aureus exists as a population of cells, and it adopts a diversity of cell types. In evolutionary biology, the concept of "bet-hedging" has established that even in positive conditions, there are members that arise within a population that would be present as non-beneficial, but if those conditions change, these traits could allow survival. For S. aureus, some of these cells within an infection have a reduced fitness, are not rapidly proliferating or are the cause of an active host response and disease, but these do remain even after the disease seems to have been cleared. This is true for persistence against immune responses but also as a continual presence in spite of antibiotic treatment. We propose that the constant arousal of suboptimal populations at any timepoint is a key strategy for S. aureus long-term infection and survival. Thus, understanding the molecular basis for this feature could be instrumental to combat persistent infections.

Frail patients having vascular surgery during the early COVID-19 pandemic experienced high rates of adverse perioperative events and amputation

BACKGROUND

Frailty predicts adverse perioperative outcomes and increased mortality in patients having vascular surgery. Frailty assessment is a potential tool to inform resource allocation, and shared decision-making about vascular surgery in the resource constrained COVID-19 pandemic environment. This cohort study describes the prevalence of frailty in patients having vascular surgery and the association between frailty, mortality and perioperative outcomes.

METHODS

The COVID-19 Vascular Service in Australia (COVER-AU) prospective cohort study evaluates 30-day and six-month outcomes for consecutive patients having vascular surgery in 11 Australian vascular units, March-July 2020. The primary outcome was mortality, with secondary outcomes procedure-related outcomes and hospital utilization. Frailty was assessed using the nine-point visual Clinical Frailty Score, scores of 5 or more considered frail.

RESULTS

Of the 917 patients enrolled, 203 were frail (22.1%). The 30 day and 6 month mortality was 2.0% (n = 20) and 5.9% (n = 35) respectively with no significant difference between frail and non-frail patients (OR 1.68, 95%CI 0.79-3.54). However, frail patients stayed longer in hospital, had more perioperative complications, and were more likely to be readmitted or have a reoperation when compared to non-frail patients. At 6 months, frail patients had twice the odds of major amputation compared to non-frail patients, after adjustment (OR 2.01; 95% CI 1.17-3.78), driven by a high rate of amputation during the period of reduced surgical activity.

CONCLUSION

Our findings highlight that older, frail patients, experience potentially preventable adverse outcomes and there is a need for targeted interventions to optimize care, especially in times of healthcare stress.

Australian guideline on diagnosis and management of peripheral artery disease: part of the 2021 Australian evidence-based guidelines for diabetes-related foot disease

BACKGROUND

Peripheral artery disease (PAD) is implicated in up to 50% of diabetes-related foot ulcers (DFU) and significantly contributes to morbidity and mortality in this population. An evidence-based guideline that is relevant to the national context including consideration of the unique geographical and health care system differences between Australia and other countries, and delivery of culturally safe care to First Nations people, is urgently required to improve outcomes for patients with PAD and DFU in Australia. We aimed to identify and adapt current international guidelines for diagnosis and management of patients with PAD and DFU to develop an updated Australian guideline.

METHODS

Using a panel of national content experts and the National Health and Medical Research Council procedures, the 2019 International Working Group on the Diabetic Foot (IWGDF) guidelines were adapted to the Australian context. The guideline adaptation frameworks ADAPTE and Grading of Recommendations Assessment, Development and Evaluation (GRADE) were applied to the IWGDF guideline for PAD by the expert panel. Recommendations were then adopted, adapted or excluded, and specific considerations for implementation, population subgroups, monitoring and future research in Australia were developed with accompanying clinical pathways provided to support guideline implementation.

RESULTS

Of the 17 recommendations from the IWGDF Guideline on diagnosis, prognosis and management of PAD in patients with diabetes with and without foot ulcers, 16 were adopted for the Australian guideline and one recommendation was adapted due to the original recommendation lacking feasibility in the Australian context. In Australia we recommend all people with diabetes and DFU undergo clinical assessment for PAD with accompanying bedside testing. Further vascular imaging and possible need for revascularisation should be considered for all patients with non-healing DFU irrespective of bedside results. All centres treating DFU should have expertise in, and/or rapid access to facilities necessary to diagnose and treat PAD, and should provide multidisciplinary care post-operatively, including implementation of intensive cardiovascular risk management.

CONCLUSIONS

A guideline containing 17 recommendations for the diagnosis and management of PAD for Australian patients with DFU was developed with accompanying clinical pathways. As part of the adaptation of the IWGDF guideline to the Australian context, recommendations are supported by considerations for implementation, monitoring, and future research priorities, and in relation to specific subgroups including Aboriginal and Torres Strait Islander people, and geographically remote people. This manuscript has been published online in full with the authorisation of Diabetes Feet Australia and can be found on the Diabetes Feet Australia website: https://www.diabetesfeetaustralia.org/new-guidelines/ .

One-Year Health Status Outcomes Following Early Invasive and Noninvasive Treatment in Symptomatic Peripheral Artery Disease

BACKGROUND

Lifestyle changes and medications are recommended as the first line of treatment for claudication, with revascularization considered for treatment-resistant symptoms, based on patients' preferences. Real-world evidence comparing health status outcomes of early invasive with noninvasive management strategies is lacking.

METHODS

In the international multicenter prospective observational PORTRAIT (Patient-Centered Outcomes Related to Treatment Practices in Peripheral Arterial Disease: Investigating Trajectories) registry, disease-specific health status was assessed by the Peripheral Artery Questionnaire in patients with new-onset or worsening claudication at presentation and 3, 6, and 12 months later. One-year health status trajectories were compared by early revascularization versus noninvasive management on a propensity-matched sample using hierarchical generalized linear models for repeated measures adjusted for baseline health status.

RESULTS

In a propensity-matched sample of 1000 patients (67.4±9.3 years, 62.8% male, and 82.4% White), 297 (29.7%) underwent early revascularization and 703 (70.3%) were managed noninvasively. Over 1 year of follow-up, patients who underwent early invasive management reported significantly higher health status than patients managed noninvasively (interaction term for time and treatment strategy; P<0.001 for all Peripheral Artery Questionnaire domains). The average 1-year change in Peripheral Artery Questionnaire summary scores was 30.8±25.2 in those undergoing early invasive, compared with 16.7±23.4 in those treated noninvasively (P<0.001).

CONCLUSIONS

Patients with claudication undergoing early invasive treatment had greater health status improvements over the course of 1 year than those treated noninvasively. These data can be used to support shared decision-making with patients.

REGISTRATION

URL: https://www.

CLINICALTRIALS

gov; Unique identifier: NCT01419080.

The shifting care and outcomes for patients with endangered limbs - Critical limb ischemia (SCOPE-CLI) registry overview of study design and rationale

BACKGROUND

Critical limb ischemia (CLI), the most severe form of peripheral artery disease, is associated with pain, poor wound healing, high rates of amputation, and mortality (>20% at 1 year). Little is known about the processes of care, patients' preferences, or outcomes, as seen from patients' perspectives. The SCOPE-CLI study was co-designed with patients to holistically document patient characteristics, treatment preferences, patterns of care, and patient-centered outcomes for CLI.

METHODS

This 11-center prospective observational registry will enroll and interview 816 patients from multispecialty, interdisciplinary vascular centers in the United States and Australia. Patients will be followed up at 1, 2, 6, and 12 months regarding their psychosocial factors and health status. Hospitalizations, interventions, and outcomes will be captured for 12 months with vital status extending to 5 years. Pilot data were collected between January and July of 2021 from 3 centers.

RESULTS

A total of 70 patients have been enrolled. The mean age was 68.4 ± 11.3 years, 31.4% were female, and 20.0% were African American.

CONCLUSIONS

SCOPE-CLI is uniquely co-designed with patients who have CLI to capture the care experiences, treatment preferences, and health status outcomes of this vulnerable population and will provide much needed information to understand and address gaps in the quality of CLI care and outcomes.ClinicalTrials.gov identifier (NCT Number): NCT04710563 https://clinicaltrials.gov/ct2/show/NCT04710563.

Eukaryotic elongation factor 2 kinase regulates foam cell formation via translation of CD36

Eukaryotic elongation factor 2 kinase (eEF2K) is an atypical protein kinase that controls protein synthesis in cells under stress. Although well studied in cancer, less is known about its roles in chronic inflammatory diseases. Here, we examined its regulation of macrophage cholesterol handling in the context of atherosclerosis. eEF2K mRNA expression and protein activity were upregulated in murine bone marrow-derived macrophages (BMDMs) exposed to oxidized low-density lipoprotein cholesterol (oxLDL). When incubated with oxLDL, BMDMs from eEF2K knockout (Eef2k^-/- ) mice formed fewer Oil Red O⁺ foam cells than Eef2k^+/+ BMDMs (12.5% ± 2.3% vs. 32.3% ± 2.0%, p < .01). Treatment with a selective eEF2K inhibitor, JAN-384, also decreased foam cell formation for C57BL/6J BMDMs and human monocyte-derived macrophages. Disabling eEF2K selectively decreased protein expression of the CD36 cholesterol uptake receptor, mediated by a reduction in the proportion of translationally active Cd36 mRNA. Eef2k^-/- mice bred onto the Ldlr^-/- background developed aortic sinus atherosclerotic plaques that were 30% smaller than Eef2k^+/+ -Ldlr^-/- mice after 16 weeks of high cholesterol diet (p < .05). Although accompanied by a reduction in plaque CD36⁺ staining (p < .05) and lower CD36 expression in circulating monocytes (p < .01), this was not associated with reduced lipid content in plaques as measured by oil red O staining. Finally, EEF2K and CD36 mRNA levels were higher in blood mononuclear cells from patients with coronary artery disease and recent myocardial infarction compared to healthy controls without coronary artery disease. These results reveal a new role for eEF2K in translationally regulating CD36 expression and foam cell formation in macrophages. Further studies are required to explore therapeutic targeting of eEF2K in atherosclerosis.

Use of Biodegradable Temporising Matrix (BTM) in the reconstruction of diabetic foot wounds: A pilot study

Introduction

Complex diabetes-related foot wounds are at high risk of infection and subsequent major amputation unless healed expediently. Biodegradable Temporising Matrix (BTM) is a synthetic matrix that facilitates the organisation of the extracellular matrix, resulting in a neodermis layer over these difficult-to-heal areas. The aim of this study was to evaluate the efficacy of using BTM in the reconstruction of challenging diabetic foot wounds.

Methods

Eighteen patients with complex diabetic foot wounds (exposed tendon, fascia, joint, bone), or chronic ulcers at high shear stress locations had BTM applied. Indications for BTM application were high shear stress location (66.6%), exposed bone (16.6%), exposed fascia (5.6%), exposed tendon (5.6%) and chronic non-healing wound (5.6%). The time to complete healing, infection rate and incidence of subsequent wound breakdown was analysed.

Discussion

Thirteen of 18 patients completed the BTM treatment regime with all these patients achieving complete wound healing at a median time of 13 weeks. One patient had partial treatment with BTM and four patients were withdrawn from the study following BTM application. The rate of infection and re-ulceration were both 15.4%.

Conclusion

This is the first prospective cohort pilot study evaluating the use of BTM for complex diabetic foot wounds. BTM demonstrates potential in healing uninfected, non-ischaemic diabetic foot wounds with exposed deep structures and chronic wounds subject to high shear stress. The re-ulceration and infection rates were relatively low for this high-risk population. BTM may also offer promise as an alternative to free flaps.

Lay Summary

The prevalence of diabetes and its complications, including foot ulcers and wounds, have significantly increased worldwide over the last 40 years. Increasingly patients are admitted to hospital for antibiotics, debridements and subsequent amputations from these wounds. Complex diabetes-associated wounds are those at highest risk of these complications or necessitating more extensive, complex operations such as free flaps. These wounds may have exposed deep structures, be at risk of high shear stress or be chronic non-healing wounds.

Temporisers are a type of material which integrates into the wound and promotes in-growth of tissue, ideal for healing over these difficult to heal areas. Biodegradable Temporising Matrix (BTM) is a synthetic temporising matrix which has demonstrated positive outcomes in facilitating healing in burns and plastics wounds, but its effectiveness in diabetic foot wounds has not yet been proven. This is the first prospective cohort pilot study evaluating the use of BTM for complex diabetic foot wounds. BTM demonstrates potential in healing uninfected, non-ischaemic complex diabetic foot wounds and potentially avoiding more complex operations.

Correction: Two-year efficacy of varenicline tartrate and counselling for inpatient smoking cessation (STOP study): A randomized controlled clinical trial

[This corrects the article DOI: 10.1371/journal.pone.0231095.].

Protocol for a prospective observational study: the Australia and New Zealand Diabetic and Ischaemic Foot Outcomes Study (ANZ-DIFOS)

INTRODUCTION

Diabetic foot disease is a common condition globally and is over-represented in indigenous populations. The propensity for patients with diabetic foot disease to undergo minor or major limb amputation is a concern. Diabetic foot disease and lower limb amputation are debilitating for patients and have a substantial financial impact on health services. The purpose of this multicentre study is to prospectively report the presentation, management and outcomes of diabetic foot disease, to validate existing scoring systems and assess long term outcomes for these patients particularly in relation to major limb amputation.

METHODS AND ANALYSIS

This is a multisite, international, prospective observational study, being undertaken at Waikato Hospital, New Zealand (NZ); Sir Charles Gairdner Hospital, the Royal Adelaide Hospital and the Queen Elizabeth Hospital, Australia. Consecutive participants with diabetic foot disease that meet inclusion criteria and agree to participate will be recruited from multidisciplinary team diabetic foot clinic, vascular clinic, dialysis and admission to hospital. Follow-up of participants will occur at 1, 3, 6 and 12 months. At recruitment and follow-up reviews, information about service details, demographic and clinical history, wound data and discharge information will be recorded. The primary outcomes are the time to wound healing, major amputation, overall mortality and amputation-free survival at 12 months. This study started in NZ in August 2020 and will commence in Australian sites in early 2021.

ETHICS AND DISSEMINATION

New Zealand Central Health and Disability Ethics Committee (20/CEN/122), Waikato DHB Research Department (RDO020044), Quality Improvement HoD Sir Charles Gairdner Hospital (39715) and the Central Adelaide Local Health Network (CALHN) Human Research Ethics Committee (13928). Results will be presented at international conferences and published in peer-reviewed journals.

TRIAL REGISTRATION NUMBER

Australian New Zealand Clinical Trials Registry (ACTRN12621000337875).

The Anti-inflammatory and Proangiogenic Properties of High-Density Lipoproteins: An Emerging Role in Diabetic Wound Healing

Significance: Prolonged inflammation and impaired angiogenesis are the two principal factors that prevent successful wound healing, which is exacerbated in people with diabetes. There is a significant need for new wound healing treatments that target both these factors simultaneously. This review discusses the emerging evidence that high-density lipoproteins (HDL) have pleiotropic wound healing benefits. Recent Advances: Numerous in vitro and in vivo studies have demonstrated the anti-inflammatory and proangiogenic effects of HDL. In endothelial cells, HDL mediate these effects through interaction with the scavenger receptor SR-BI, which activates the PI3K/Akt pathway, causing a decrease in inflammatory protein production and an increase in proangiogenic growth factors. In macrophages, HDL inhibit inflammation through suppression of the nuclear factor kappa B activation pathway. This review details the molecular disturbances that cause impaired wound healing in diabetes with a particular focus on inflammation and angiogenesis and the pathways in which HDL provide benefit. Critical Issues: Diabetic foot ulcers (DFUs) impose a major public health challenge worldwide. It is estimated that 20% patients with DFUs require amputation, which is accompanied by a significant social and economic burden. To date, there are no therapeutic agents with pleiotropic effects that actively improve wound healing, highlighting a therapeutic void for this complex disease.

Plasma-polymerized pericyte patches improve healing of murine wounds through increased angiogenesis and reduced inflammation

Pericytes have the potential to be developed as a cell therapy for the treatment of wounds; however, the efficacy of any cell therapy relies on the successful delivery of intact and functioning cells. Here, the effect of delivering pericytes on wound repair was assessed alongside the development of a surface-functionalized pericyte patch. Plasma polymerization (PP) was used to functionalize the surface of silicone patches with heptylamine (HA) or acrylic acid (AA) monomers. Human pericytes were subsequently delivered to murine excisional wounds by intradermal injection or using the pericyte-laden patches and the comparative effects on wound healing, inflammation and revascularization determined. The AA surface provided the superior transfer of the cells to de-epidermized dermis. Excisional murine wounds treated either with pericytes injected directly into the wound or with the pericyte-laden AA patches showed improved healing with decreased neutrophil infiltration and reduced numbers of macrophages in the wounds. Pericyte delivery also enhanced angiogenesis through a mechanism independent of VEGF signalling. Pericytes, when delivered to wounds, improved healing responses by dampening inflammation and promoting angiogenesis. Delivery of pericytes using PP-AA-functionalized patches was equally as effective as direct injection of pericytes into wounds. Pericyte-functionalized dressings may therefore be a clinically relevant approach for the treatment of wounds.

Factors Associated With Key Outcomes in Diabetes Related Foot Disease: A Prospective Observational Study

OBJECTIVE

Diabetic foot disease is a serious and common complication of diabetes mellitus. The aim of this study was to assess limb and patient factors associated with key clinical outcomes in diabetic patients with foot ulcers.

METHODS

This was a prospective observational study of diabetic patients with foot wounds admitted to a major tertiary teaching hospital in South Australia or seen at associated multidisciplinary foot clinics between February 2017 and December 2018. Patient demographic and clinical data were collected, including limb status severity assessed by the WIfI system and grip strength. Participants were followed up for 12 months. The primary outcomes were major amputation, death, amputation free survival, and completion of healing of the index wound within one year.

RESULTS

A total of 153 participants were recruited and outcome data were obtained for 152. Forty-two participants underwent revascularisation during the research period. Eighteen participants (11.8%) suffered major amputation of the index limb and 16 (10.5%) died during follow up. Complete wound healing was achieved in 106 (70%) participants. There was a statistically significant association between WIfI stage and major amputation (subdistribution hazard ratio [SHR] 2.75), mortality (hazard ratio [HR] 2.60), amputation free survival (odds ratio [OR] 0.32), and wound healing (SHR 0.69). There was also a statistically significant association between time to healing and grip strength (SHR 0.50), and previous amputations (major or minor) (SHR 0.57).

CONCLUSION

This prospective study supports the ability of the WIfI classification system to predict one year key clinical outcomes in a diabetic population with foot ulcers. It also demonstrated that grip strength may be a useful predictor of wound healing.

Variability in utilization of diagnostic imaging tests in patients with symptomatic peripheral artery disease

AIM

Imaging can help guide management in peripheral arterial disease (PAD) with symptoms refractory to medical treatment. However, there are no set guidelines to determine when physicians should seek further imaging in patients with PAD for the assessment of new, persistent or worsening symptoms. This study describes the rates and variability in non-invasive and invasive imaging for patients presenting to vascular specialty clinics for symptomatic PAD.

METHODS

Patients (n=1,275) with a new PAD diagnosis or exacerbation of PAD symptoms were enrolled from 16 vascular clinics. Hierarchical logistic regression models were used to estimate the referral rates for 1) non-invasive and 2) invasive imaging tests, after adjusting for patient demographics, disease characteristics, PAQ summary score, PAD performance measures and country. Median Odds Ratios (MOR) were calculated to examine the variability across sites and providers.

RESULTS

Mean ABI was 0.67 ± 0.19. There were 690 (54.1%) patients who had imaging, of which 62 (9.0%) had invasive imaging. Imaging rates ranged from 8.6% to 98.6% across sites. The MOR for use of imaging for site was 3.36 (p < 0.001) and provider 3.49 (p < 0.001). The variability was explained primarily by (R² = 29%) country followed by patient-level factors, provider and lastly site (R² = 17%, 14%, and 13%, respectively).

CONCLUSION

There is wide variation in the use of imaging for patients presenting with new onset or recent exacerbations of their PAD. Country, followed by provider and site, were most strongly associated with this variability after adjusting for patient characteristics.

Assessment of a smartphone-based application for diabetic foot ulcer measurement

The accurate measurement of diabetic foot ulcer (DFU) wound size is essential as the rate of wound healing is a significant prognostic indicator of the likelihood of complete wound healing. Mobile phone photography is often used for surveillance and to aid in telemedicine consultations. However, there remains no accurate and objective measurement of wound size integrated into these photos. The NDKare mobile phone application has been developed to address this need and our study evaluates its accuracy and practicality for DFU wound size assessment. The NDKare mobile phone application was evaluated for its accuracy in two- (2D) and three-dimensional (3D) wound measurement. One hundred and fifteen diabetic foot wounds were assessed for wound surface area, depth and volume accuracy in comparison to Visitrak and the WoundVue camera. Thirty five wounds had two assessors with different mobiles phones utilizing both applications to assess the reproducibility of the measurements. The 2D surface area measurements by NDKare showed excellent concordance with Visitrak and WoundVue measurements (ICC: 0.991 [95% CI: 0.988, 0.993]) and between different users (ICC: 0.98 [95% CI: 0.96, 0.99)]. The 3D NDKare measurements had good agreement for depth and fair agreement for volume with the WoundVue camera. The NDKare phone application can consistently and accurately obtain 2D measurements of diabetic foot wounds with mobile phone photography. This is a quick and readily accessible tool which can be integrated into comprehensive diabetic wound care.

Long-term outcomes following endovascular and surgical revascularization for peripheral artery disease: a propensity score-matched analysis

AIMS

Peripheral artery disease (PAD) revascularization can be performed by either endovascular or open surgical approach. Despite increasing use of endovascular revascularization, it is still uncertain which strategy yields better long-term outcomes.

METHODS AND RESULTS

This retrospective cohort study evaluated patients hospitalized with PAD in Australia and New Zealand who underwent either endovascular or surgical revascularization between 2008 and 2015, and compared procedures using a propensity score-matched analysis. Hybrid interventions were excluded. The primary endpoint was mortality or major adverse limb events (MALE), defined as a composite endpoint of acute limb ischaemia, urgent surgical or endovascular reintervention, or major amputation, up to 8 years post-hospitalization using time-to-event analyses 75 189 patients fulfilled eligibility (15 239 surgery and 59 950 endovascular), from whom 14 339 matched pairs (mean ± SD age 71 ± 12 years, 73% male) with good covariate balance were identified. Endovascular revascularization was associated with an increase in combined MALE or mortality [hazard ratio (HR) 1.13, 95% confidence interval (CI): 1.09-1.17, P < 0.001]. There was a similar risk of MALE (HR 1.04, 95% CI: 0.99-1.10, P = 0.15), and all-cause urgent rehospitalizations (HR 1.01, 95% CI: 0.98-1.04, P = 0.57), but higher mortality (HR 1.16, 95% CI: 1.11-1.21, P < 0.001) when endovascular repair was compared to surgery. In subgroup analysis, these findings were consistent for both claudication and chronic limb-threatening ischaemia presentations.

CONCLUSION

Although the long-term risk of MALE was comparable for both approaches, enduring advantages of surgical revascularization included lower long-term mortality. This is at odds with some prior PAD studies and highlights contention in this space.

Efficacy of Telmisartan to Slow Growth of Small Abdominal Aortic Aneurysms: A Randomized Clinical Trial

Importance

Currently there is no drug therapy for abdominal aortic aneurysm (AAA).

Objective

To test the efficacy of the angiotensin receptor blocker telmisartan in slowing AAA growth in the Telmisartan in the Management of Abdominal Aortic Aneurysm (TEDY) trial.

Design, Setting, and Participants

A randomized, double-blind, placebo-controlled trial recruited participants between September 6, 2011, and October 5, 2016, to evaluate the efficacy of telmisartan treatment in patients with AAA. Participants with 35- to 49-mm AAAs recruited from Australia, the Netherlands, and the US were randomized 1:1 to receive telmisartan, 40 mg, or identical placebo. Analyses were conducted according to intention-to-treat principles. Final follow-up was conducted on October 11, 2018, and data analysis was performed between June and November 2019.

Intervention

Telmisartan, 40 mg, or identical placebo.

Main Outcomes and Measures

The primary outcome of the difference in AAA growth, assessed on core imaging laboratory-read ultrasonographic scanning, was tested with linear mixed-effects models. Other outcomes included effects on blood pressure, computed tomographic (CT)-measured AAA diameter and volume, time to AAA-related events (AAA repair or mortality due to AAA rupture), and health-related quality of life.

Results

Of 300 intended participants, 210 were enrolled and randomized to receive telmisartan (n = 107) or placebo (n = 103). Of patients included in the intention-to-treat analysis (telmisartan: n = 106, placebo: n = 101), 183 were men (88%); mean (SD) age was 73.5 (7.9) years. At 1 year, participants receiving telmisartan had mean lower systolic (8.9; 95% CI, 4.1-13.8 mm Hg; P < .001) and diastolic (7.0; 4.3-9.8 mm Hg; P < .001) blood pressure levels compared with participants receiving placebo. A total of 188 participants (91%) received at least 2 ultrasonographic scans and 133 participants (64%) had at least 2 CT scans. There was no significant difference in ultrasonographic-assessed AAA growth rates among those assigned telmisartan (1.68 mm/y) or placebo (1.78 mm/y): mean difference, -0.11 mm/y (95% CI, -0.60 to 0.38 mm/y; P = .66). Telmisartan had no significant effects on AAA growth assessed by CT-measured AAA diameter (mean difference, -0.01 mm/y; 95% CI, -0.02 to 0.01 mm/y; P = .23) or volume (mean difference, -0.02 cm3/y; 95% CI, -0.04 to 0.00 cm3/y; P = .11), AAA-related events (relative risk, 1.35; 95% CI, 0.54-3.35; P = .52), or health-related quality of life (mean difference in physical component score at 24 months, 0.4; 95% CI, 0.4-0.4; P = .80). Hypotensive symptoms (eg, syncope) were twice as common among participants receiving telmisartan compared with placebo (28 [26%] vs 13 [13%]; P = .02), but overall adverse event rates were otherwise similar for both groups.

Conclusions and Relevance

This underpowered study did not show a treatment effect for telmisartan on small AAA growth. Future trials will need to ensure adequate sample size and duration of follow-up.

Trial Registrations

anzctr.org.au Identifier: ACTRN12611000931976; ClinicalTrials.gov Identifier: NCT01683084.

Evaluation of a Novel Three-Dimensional Wound Measurement Device for Assessment of Diabetic Foot Ulcers

Objective: The initial wound measurement and regular monitoring of diabetic foot ulcers (DFU) is critical to assess treatment response. There is no standardized, universally accepted, quick, reliable, and quantitative assessment method to characterize DFU. To address this need, a novel topographic imaging system has been developed. Our study aims at assessing the reliability and practicality of the WoundVue^® camera technology in the assessment of DFU. Approach: The WoundVue system is a prototype device. It consists of two infrared cameras and an infrared projector, and it is able to produce a three-dimensional (3D) reconstruction of the wound structure. Fifty-seven diabetic foot wounds from patients seen in a multidisciplinary foot clinic were photographed from two different angles and distances by using the WoundVue camera. Wound area, volume, and maximum depth were measured for assessment of reliability. Thirty-one of these wounds also had area calculated by using the established Visitrak™ system, and a correlation between the area obtained by using both systems was assessed. Results: WoundVue images analysis showed excellent agreement for area (intraclass correlation coefficient [ICC]: 0.995), volume (ICC: 0.988), and maximum depth (ICC: 0.984). Good agreement was found for area measurement by using the WoundVue camera and Visitrak system (ICC: 0.842). The average percentage differences between measures obtained by using the WoundVue from different angles for assessment of different sizes and shapes of wounds were 2.9% (95% confidence interval [CI]: 0.3-5.4), 12.9% (95% CI: 9.6-35.7), and 6.2% (95% CI: 2.3-14.7) for area, maximum depth, and volume, respectively. Innovation: This is the first human trial evaluating this novel 3D wound measurement device. Conclusion: The WoundVue system is capable of recreating a 3D model of DFU and produces consistent data. Digital images are ideal for monitoring wounds over time, and the WoundVue camera has the potential to be a valuable adjunct in diabetic foot wound care.

Attenuation of Flightless I Increases Human Pericyte Proliferation, Migration and Angiogenic Functions and Improves Healing in Murine Diabetic Wounds

Pericytes are peri-vascular mural cells which have an important role in the homeostatic regulation of inflammatory and angiogenic processes. Flightless I (Flii) is a cytoskeletal protein involved in regulating cellular functions, but its involvement in pericyte activities during wound healing is unknown. Exacerbated inflammation and reduced angiogenesis are hallmarks of impaired diabetic healing responses, and strategies aimed at regulating these processes are vital for improving healing outcomes. To determine the effect of altering Flii expression on pericyte function, in vitro and in vivo studies were performed to assess the effect on healing, inflammation and angiogenesis in diabetic wounds. Here, we demonstrated that human diabetic wounds display upregulated expression of the Flii protein in conjunction with a depletion in the number of platelet derived growth factor receptor β (PDGFRβ) +/ neural glial antigen 2 (NG2) + pericytes present in the dermis. Human pericytes were found to be positive for Flii and attenuating its expression in vitro through siRNA knockdown led to enhanced proliferation, migration and angiogenic functions. Genetic knockdown of Flii in a streptozotocin-induced murine model of diabetes led to increased numbers of pericytes within the wound. This was associated with dampened inflammation, an increased rate of angiogenic repair and improved wound healing. Our findings show that Flii expression directly impacts pericyte functions, including proliferation, motility and angiogenic responses. This suggests that Flii regulation of pericyte function may be in part responsible for the changes in pericyte-related processes observed in diabetic wounds.

Efficacy of phage cocktail AB-SA01 therapy in diabetic mouse wound infections caused by multidrug-resistant Staphylococcus aureus

BACKGROUND

Diabetic foot ulcer (DFU) is a serious complication of diabetes mellitus. Antibiotic-resistant Staphylococcus aureus is frequently isolated from DFU infections. Bacteriophages (phages) represent an alternative or adjunct treatment to antibiotic therapy. Here we describe the efficacy of AB-SA01, a cocktail of three S. aureus Myoviridae phages, made to current good manufacturing practice (cGMP) standards, and which has undergone two phase I clinical trials, in treatment of multidrug-resistant (MDR) S. aureus infections.

RESULTS

Wounds of saline-treated mice showed no healing, but expanded and became inflamed, ulcerated, and suppurating. In contrast, AB-SA01 treatment decreased the bacterial load with efficacy similar or superior to vancomycin treatment. At the end of the treatment period, there was a significant decrease (p < 0.001) in bacterial load and wound size in infected phage- and vancomycin-treated groups compared with infected saline-treated mice. In phage-treated mice, wound healing was seen similar to vancomycin treatment. No mortality was recorded associated with infections, and post-mortem examinations did not show any evident pathological lesions other than the skin wounds. No adverse effects related to the application of phages were observed.

CONCLUSION

Topical application of phage cocktail AB-SA01 is effective, as shown by bacterial load reduction and wound closure, in the treatment of diabetic wound infections caused by MDR S. aureus. Our results suggest that topical phage cocktail treatment may be effective in treating antibiotic-resistant S. aureus DFU infections.

Abstract 24: Health Status Differences Between Early Invasive and Non Invasive Treatment Strategies in Patients With Peripheral Artery Disease: Insights From Portrait Registry

Background: In patients with symptomatic peripheral artery disease (PAD), a key treatment goal is to improve their health status; their symptoms, function, and quality of life (QoL). While medical therapy with lifestyle changes is recommended in all, revascularization can be a consideration to alleviate PAD symptoms. We sought to compare the real-world impact of either treatment strategy on patients’ health status improvement.

Methods: Patients with new or worsening PAD symptoms (Rutherford category 1-3), from 10 U.S. specialty vascular clinics between 2011-2015, who either underwent early revascularization (using stent, angioplasty or surgery within 3 months of enrolment) or medical management alone (statin, aspirin, cilostazol, supervised exercise therapy, risk factor (diabetes, hypertension) management) were identified from the Patient-Centered Outcomes Related to Treatment Practices in Peripheral Arterial Disease: Investigating Trajectories (PORTRAIT) registry. The Peripheral Artery Questionnaire (PAQ) was used to assess patients’ disease-specific health status at enrollment and at 3, 6 and 12 months of follow up. The differences in PAQ overall summary scores, and each subdomain, were compared using an adjusted generalized linear model for repeated measures (Figure 1).

Results: Among 797 patients (mean age of 68.6 years, 58.1% male), 226 underwent early revascularization and 571 were managed medically. At baseline, patients in the revascularization vs. medical management cohort had lower PAQ summary scores (mean ± SD; 42.6 ± 20.7 vs. 48.5 ± 22.3, P<0.001) and QoL scores (43.4 ± 23.9 vs. 50.4 ± 26.4, P<0.001). Over 1 year of follow-up, patients who underwent revascularization reported significantly higher health status over time than patients managed medically without revascularization (P <0.001 for all PAQ sub-domains; Figure 1).

Conclusion: Patients with PAD who received early revascularization had worse health status at baseline, but they reported a greater degree of improvement over 1 year of follow-up when compared to patients managed medically without revascularization. Summarizing real-world health status benefits following a PAD diagnosis is critical to help guide preference-sensitive decisions on PAD management.

Two-year efficacy of varenicline tartrate and counselling for inpatient smoking cessation (STOP study): A randomized controlled clinical trial

INTRODUCTION

Varenicline tartrate is superior for smoking cessation to other tobacco cessation therapies by 52 weeks, in the outpatient setting. We aimed to evaluate the long-term (104 week) efficacy following a standard course of inpatient-initiated varenicline tartrate plus Quitline-counselling compared to Quitline-counselling alone.

METHODS

Adult patients (n = 392, 20-75 years) admitted with a smoking-related illnesses to one of three hospitals, were randomised to receive either 12-weeks of varenicline tartrate (titrated from 0.5mg daily to 1mg twice-daily) plus Quitline-counselling, (n = 196) or Quitline-counselling alone, (n = 196), with continuous abstinence from smoking assessed at 104 weeks.

RESULTS

A total of 1959 potential participants were screened for eligibility between August 2008 and December 2011. The proportion of participants who remained continuously abstinent (intention-to-treat) at 104 weeks were significantly greater in the varenicline tartrate plus counselling arm (29.2% n = 56) compared to counselling alone (18.8% n = 36; p = 0.02; odds ratio 1.78; 95%CI 1.10 to 2.86, p = 0.02). Twenty-two deaths occurred during the 104 week study (n = 10 for varenicline tartrate plus counselling and n = 12 for Quitline-counselling alone). All of these participants had known or developed underlying co-morbidities.

CONCLUSIONS

This is the first study to examine the efficacy and safety of varenicline tartrate over 104 weeks within any setting. Varenicline tartrate plus Quitline-counselling was found to be an effective opportunistic treatment when initiated for inpatient smokers who had been admitted with tobacco-related disease.