Bacterial protease activity as a biomarker to assess the risk of non-healing in chronic wounds: Results from a multicentre randomised controlled clinical trial.

Millions worldwide suffer from chronic wounds challenging clinicians and burdening healthcare systems. Bacteria impede wound healing; however, the diagnosis of excessive bacterial burden or infection is elusive. Clinical signs and symptoms of infection are inaccurate and unreliable. This trial evaluated a novel, point-of-care, lateral flow diagnostic designed to detect virulence factors released by the most common bacteria found in chronic wounds. A multicentre prospective cohort clinical trial examined the efficacy of a diagnostic test in detecting bacterial proteases taken from swab samples of chronic venous, arterial, pressure and mixed aetiology chronic wounds. Two hundred and sixty six wounds were included in the analysis of the study. The wounds were tested at the start of the study after which investigators were permitted to use whatever dressings they desired for the next 12 weeks. Healing status at 12 weeks was assessed. The presence of elevated bacterial protease activity decreased the probability of wound healing at 12 weeks. In contrast, a greater proportion of wounds were healed at 12 weeks if they had little or no bacterial protease activity at study start. In addition, the presence of elevated bacterial protease activity increased the time it takes for a wound to heal and increased the risk that a wound would not heal, when compared to the absence of bacterial protease activity. The results of this clinical trial indicate that bacterial protease activity, as detected by this novel diagnostic test, is a valid clinical marker for chronicity in wounds. The diagnostic test offers a tool for clinicians to detect clinically significant bacteria in real time and manage bacteria load before the clinical signs and symptoms of infection are evident.

Diagnostic Accuracy of Point-of-Care Fluorescence Imaging for the Detection of Bacterial Burden in Wounds: Results from the 350-Patient Fluorescence Imaging Assessment and Guidance Trial.

Objective: High bacterial load contributes to chronicity of wounds and is diagnosed based on assessment of clinical signs and symptoms (CSS) of infection, but these characteristics are poor predictors of bacterial burden. Point-of-care fluorescence imaging (FL) MolecuLight i:X can improve identification of wounds with high bacterial burden (>104 colony-forming unit [CFU]/g). FL detects bacteria, whether planktonic or in biofilm, but does not distinguish between the two. In this study, diagnostic accuracy of FL was compared to CSS during routine wound assessment. Postassessment, clinicians were surveyed to assess impact of FL on treatment plan. Approach: A prospective multicenter controlled study was conducted by 20 study clinicians from 14 outpatient advanced wound care centers across the United States. Wounds underwent assessment for CSS followed by FL. Biopsies were collected to confirm total bacterial load. Three hundred fifty patients completed the study (138 diabetic foot ulcers, 106 venous leg ulcers, 60 surgical sites, 22 pressure ulcers, and 24 others). Results: Around 287/350 wounds (82%) had bacterial loads >104 CFU/g, and CSS missed detection of 85% of these wounds. FL significantly increased detection of bacteria (>104 CFU/g) by fourfold, and this was consistent across wound types (p < 0.001). Specificity of CSS+FL remained comparably high to CSS (p = 1.0). FL information modified treatment plans (69% of wounds), influenced wound bed preparation (85%), and improved overall patient care (90%) as reported by study clinicians. Innovation: This novel noncontact, handheld FL device provides immediate, objective information on presence, location, and load of bacteria at point of care. Conclusion: Use of FL facilitates adherence to clinical guidelines recommending prompt detection and removal of bacterial burden to reduce wound infection and facilitate healing.

A multicenter, randomized, controlled clinical trial evaluating the use of dehydrated human amnion/chorion membrane allografts and multilayer compression therapy vs. multilayer compression therapy alone in the treatment of venous leg ulcers.

Venous leg ulcers produce significant clinical and economic burdens on society and often require advanced wound therapy. The purpose of this multicenter, randomized, controlled study is to evaluate the safety and efficacy of one or two applications of dehydrated human amnion/chorion membrane allograft and multilayer compression therapy vs. multilayer compression therapy alone in the treatment of venous leg ulcers. The primary study outcome was the proportion of patients achieving 40% wound closure at 4 weeks. Of the 84 participants enrolled, 53 were randomized to receive allograft and 31 were randomized to the control group of multilayer compression therapy alone. At 4 weeks, 62% in the allograft group and 32% in the control group showed a greater than 40% wound closure (p = 0.005), thus showing a significant difference between the allograft-treated groups and the multilayer compression therapy alone group at the 4-week surrogate endpoint. After 4 weeks, wounds treated with allograft had reduced in size a mean of 48.1% compared with 19.0% for controls. Venous leg ulcers treated with allograft had a significant improvement in healing at 4 weeks compared with multilayer compression therapy alone.