Treating diabetic foot ulcers with antimicrobial wound dressing impregnated with dialkylcarbamoyl chloride

OBJECTIVE

Diabetic foot ulcers (DFUs) are at significant risk of becoming infected, with an associated elevated risk of amputation. Choosing an appropriate treatment would help prevent infection, improve healing and patients' quality of life, as well as reduce healthcare costs. The aim of this study was to assess the efficacy of a dialkylcarbamoyl chloride (DACC)-coated wound dressing to reduce bacterial load in the treatment of infected diabetic foot ulcers with signs of biofilm.

METHOD

In this prospective, descriptive observational study, patients with infected DFUs were treated with a DACC-coated wound dressing, and were followed until complete healing was achieved. Levels of bacterial load and the presence of biofilm were also assessed.

RESULTS

The patients consisted of 42 males and 19 females, with a mean age of 54.4 years. All wounds exhibited complete wound closure upon treatment with the DACC-coated wound dressing, with an average time to heal of 71.8 days. A total of 53 patients had received systemic antibiotic treatment prior to study enrolment, and the number of patients requiring antibiotic treatment reduced to 20 during the study. The level of bacterial load (including biofilm) was reduced, leading to wound progression in a proportion of wounds.

CONCLUSION

The findings of this study revealed that treatment with a non-medicated antimicrobial wound dressing was an appropriate dressing choice to reduce microbial load and aid promotion of healing in infected DFUs with the presence of biofilm.

Experimental and clinical evidence for DACC-coated dressings: an update

OBJECTIVE

To update the evidence in relation to the use of dialkylcarbamoyl chloride (DACC)-coated wound dressings in the prevention, treatment and management of wounds.

METHOD

PubMed and PubMed Central databases were searched to identify articles published since 2020 describing the experimental and clinical evidence for DACC-coated dressings, and their antimicrobial effect, as well as their impact on the prevention and treatment of infected wounds. The identified articles were then narratively reviewed.

RESULTS

The search yielded 113 articles (plus references from ad hoc sources), of which nine met the inclusion criteria. Of the nine included studies, five related to clinical aspects and four were laboratory studies.

CONCLUSION

A number of new studies have provided further evidence for the mode of action of the antimicrobial effect of DACC-coated dressings and its wide spectrum effect (including World Health Organization-prioritised microorganisms). Additional clinical studies have provided evidence of new applications, such as in treating wounds in paediatric patients, and extended the evidence relating to their use in treating surgical site infections. Evidence also shows that DACC-coated wound dressings can aid in the binding of biofilms, and how this technology can align and support antimicrobial stewardship in the prevention of antimicrobial resistance.

Dialkyl Carbamoyl Chloride-Coated Dressing Prevents Macrophage and Fibroblast Stimulation via Control of Bacterial Growth: An In Vitro Assay

In this work, we evaluated the direct effect of a dialkyl carbamoyl chloride (DACC)-coated dressing on Staphylococcus aureus adhesion and growth in vitro, as well as the indirect effect of the dressing on fibroblast and macrophage activity. S. aureus cultures were treated with the dressing or gauze in Müller-Hinton medium or serum-supplemented Dulbecco’s modified Eagle medium. Bacterial growth and attachment were assessed through colony-forming units (CFU) and residual biomass analyses. Fibroblast and macrophage co-cultures were stimulated with filtered supernatants from the bacterial cultures treated with the DACC-coated dressing, following which tumor necrosis factor (TNF)-α/transforming growth factor (TGF)-β1 expression and gelatinolytic activity were assessed by enzyme-linked immunosorbent assays (ELISA) and zymography, respectively. The DACC-coated dressing bound 1.8−6.1% of all of the bacteria in the culture. Dressing-treated cultures presented biofilm formation in the dressing (enabling mechanical removal), with limited formation outside of it (p < 0.001). Filtered supernatants of bacterial cultures treated with the DACC-coated dressing did not over-stimulate TNF-α or TGF-β1 expression (p < 0.001) or increase gelatinolytic activity in eukaryotic cells, suggesting that bacterial cell integrity was maintained. Based on the above data, wound caregivers should consider the use of hydrophobic dressings as a first option for the management of acute or chronic wounds.

Effect of a DACC-coated dressing on keratinocytes and fibroblasts in wound healing using an in vitro scratch model

Wound dressings that exert an antimicrobial effect in order to prevent and treat wound infections can be harmful to the wound healing process. Dressings with hydrophobic coatings, however, have been suggested to both reduce the microbial load and promote the healing process. Therefore, the potential effects of a dialkylcarbamoyl chloride (DACC)-coated dressing on fibroblasts and keratinocytes in wound healing were studied using mechanical scratch wounding of confluent cell layers as an in vitro model. Additionally, gene expression analysis by qRT-PCR was used to elucidate the longitudinal effects of the DACC-coated dressing on cell responses, specifically inflammation, growth factor induction and collagen synthesis. DACC promoted cell viability, did not stick to the cell layers, and supported normal wound healing progression in vitro. In contrast, cells became attached to the uncoated reference material, which inhibited scratch closure. Moreover, DACC slightly induced KGF, VEGF, and GM-CSF expression in HaCaT cells and NHDF. Physiological COL1A1 and COL3A1 gene expression by NHDF was observed under DACC treatment with no observable effect on S100A7 and RNASE7 levels in HaCaT cells. Overall, the DACC coating was found to be safe and may positively influence the wound healing outcome. Graphical abstract.

Dialkylcarbamoyl chloride-coated versus alginate dressings after pilonidal sinus excision: a randomized clinical trial (SORKYSA study)

Background

Disease of the pilonidal sinus is a common condition that affects mainly young adults. Options for management include excision of the sinus tracts, leaving the wound open to heal by secondary intention. The aim of this study was to compare wound healing with dialkylcarbamoyl chloride (DACC)‐coated dressings versus alginate dressings.

Methods

This multicentre trial randomized consecutive patients undergoing surgery for pilonidal disease to postoperative wound care with either DACC‐coated or alginate dressings. The primary outcome was the proportion of wounds healed after 75 days. Secondary outcomes were the local status of wounds during the healing process, the quality assessment of the dressings by the patient, and the time needed to return to usual activities.

Results

A total of 246 patients were included: 120 in the DACC‐coated group and 126 in the alginate group. In per‐protocol analysis, there were significantly more patients with completely healed wounds after 75 days in the DACC group than in the alginate group: 78 of 103 (75·7 per cent) versus 58 of 97 (60 per cent) respectively (odds ratio 2·55, 95 per cent c.i. 1·12 to 5·92; P = 0·023). During follow‐up, wounds with alginate dressings had more fibrin than those with DACC‐coated dressings, but the difference was not significant (P = 0·079). There was no difference between the two arms in patients' assessment of the dressings.

Conclusion

The number of wounds completely healed at 75 days was significantly higher for DACC‐coated compared with alginate dressings. However, the preplanned, clinically significant improvement in healing of 20 per cent was not reached. Registration number: NCT02011802 ( https://clinicaltrials.gov/).

5th Congress of WUWHS Abstract book Florence, Italy September 25–29 2016

The abstract book contains the abstracts of keynote lectures, focus sessions, symposia, workshops, AIUC annual meeting, AISLEC annual meeting, EPUAP annual meeting, ETRS special session, sponsor symposia, oral presentations, poster presentations and the subject index.

Colorectal Cancer Cells Adhere to Traumatized Peritoneal Tissue in Clusters, An Experimental Study

Purpose/Aim: Colorectal malignity is one of the most common forms of cancer. The finding of free intraperitoneal colorectal cancer cells during surgery has been shown to be associated with poor outcome. The aim of this study was to develop an experimental model designed to investigate adhesion of colorectal cancer cells to the peritoneal surface.

MATERIALS AND METHODS

Two human experimental models were developed, the first using cultured mesothelial cells and the second consisting of an ex vivo model of peritoneal tissue. Both models were subjected to standardized trauma, following which labeled colorectal cancer cells (Colo205) were introduced. Adhesion of tumor cells was monitored using microscopy and detection of fluorochromes.

RESULTS

The mesothelial cell layers and peritoneal membranes remained viable in culture medium for several weeks. In our experimental model, the tumor cells added were seen to adhere to the edges of the traumatized area in cluster formations.

CONCLUSIONS

The use of human peritoneal tissue in an ex vivo model would appear to be a potentially useful tool for the study of interaction between human peritoneal membrane and free tumor cells. Experimental surgical trauma increases the ability of tumor cells to adhere to the peritoneal membrane. This ex vivo model should be useful in future studies on biological interactions between peritoneum and tumor cells in the search for novel forms of peritoneal cancer therapy.

Dialkylcarbamoyl chloride-impregnated dressing for the prevention of surgical site infection in women undergoing cesarean section: a pilot study

INTRODUCTION

Incisional surgical site infections (SSIs) occur in approximately 1.8-9.2% of patients undergoing cesarean section (CS) and contribute to prolonged hospitalization time and increased treatment costs. Dressings impregnated with dialkylcarbamoyl chloride (DACC) are an innovative approach to wound treatment based on a solely physical mechanism of action, and therefore can be used safely and without time restrictions in women during the puerperal and lactation period.

MATERIAL AND METHODS

A single-blinded randomized, controlled pilot study was conducted at the Mazovian Bródno Hospital, a tertiary care hospital, between December 2013 and March 2014, and it evaluated the presence of superficial and deep SSIs in patients during the first 14 days after a CS. Patients were randomly allocated to receive treatment with either a DACC dressing or a standard surgical dressing.

RESULTS

One hundred and forty-two patients after planned or emergency CS were enrolled in the study. No significant differences between the groups were observed with regard to patients' basic demographic and perioperative characteristics. The rate of superficial and deep SSIs was 2.8% in the group of patients who received a DACC dressing compared to 9.8% in the group with a standard surgical dressing (p = 0.08). Patients with SSIs who received a standard surgical dressing required systemic antibiotic therapy significantly more frequently (p = 0.03). Based on the logistic regression model developed, the pre-pregnancy body mass index was the only statistically significant risk factor for SSI (p = 0.015).

CONCLUSIONS

The results of the pilot study indicate a decreasing tendency of the SSI rate in patients after a CS who received DACC impregnated dressings.

In vitro and clinical experience of Cutimed Sorbact: the evidence base

In the previous chapter, Keith Cutting and James McGuire explored the link between infection and wound chronicity and explained how Cutimed Sorbact can be used to promote healing in chronic wounds. The following sections summarise the existing evidence for the Cutimed Sorbact range of dressings.

TGF-β1 promotes transition of mesothelial cells into fibroblast phenotype in response to peritoneal injury in a cell culture model

BACKGROUND

Peritoneal adhesions are a clinical problem. A key to the understanding of peritoneal adhesions is to study the healing of mesothelial cells within the peritoneal cavity following surgery. Transforming growth factor beta (TGF-βs) affects this healing process. The aim of this study was to investigate the effects of different concentrations of TGF-β1 on the healing rate and healing properties of mesothelial cells.

MATERIALS AND METHODS

Human mesothelial cells from peritoneal fluid were collected, cultured and a mechanical wound was created. The restoration of the mesothelial surface with and without increasing concentrations of TGF-β1 was monitored.

RESULTS

The denuded area was restored within 24 h. The healing rate was most extensive between the first and second hour after the damage (61.9 ± 22.8 μm/h). No significant difference in healing rate were observed when increasing levels of TGF-β1 were used. However, higher concentrations of TGF-β1 increased cell size and the cells presented more fibroblast specific properties. Lower TGF-β1 concentrations increased the number of proliferating cells.

CONCLUSIONS

This study indicates the importance of high levels TGF-β1 in mesothelial cell healing, mainly by changing the actual healing properties of the cells. Elevated levels of TGF-β1 might promote mesothelial cell transition towards a more fibroblast-like appearance.