Current research on fungi in chronic wounds.

The survey on prevailing medical practices for non-healing chronic wounds and its impact provides valuable insights into the management and treatment strategies adopted in the context of chronic wound care. The discussion highlights key findings related to diabetes as a prevalent cause, wound location, treatment approaches, and the utilization of serological tests. Diabetes emerged as a significant risk factor for chronic wounds, with 90% of the respondents having a family history of diabetes, and 70% currently under medication for diabetes management. These findings emphasize the crucial role of diabetes in contributing to non-healing chronic wounds. Healthcare providers should prioritize diabetic patients for preventive wound care measures and regular assessments to reduce the incidence of chronic wounds. The survey reveals that a substantial proportion of chronic wounds (75%) are diabetes-related, further supporting the link between diabetes and wound development. Infection-related wounds (10%), autoimmune-related wounds (3%), and other causes (5%) also contribute to the overall burden of chronic wounds. Understanding the various causative factors allows healthcare professionals to tailor treatment plans accordingly and address the specific needs of individual patients. The location of wounds showed a gender disparity, with a higher prevalence of chronic wounds in male limbs (74%) compared to female limbs (26%). Similarly, chronic wounds in other sites were more common in males (74%) than females (26%). The reasons for these gender-based differences warrant further investigation and consideration in treatment planning. In terms of treatment and management, nearly all respondents (100%) were on multiple antibiotics for wound care, indicating the widespread use of antimicrobial therapy. Additionally, a significant portion of respondents (57%) reported trying alternative treatment approaches, suggesting the need for a more diverse and holistic approach to chronic wound management. Hospitalization for chronic wound care was common, with 80% of the respondents having been hospitalized multiple times. This suggests that chronic wounds often require extensive medical attention and resources, making the management of chronic wounds a challenging and resource- intensive aspect of healthcare. The utilization of wound-related serological tests was relatively low, with only 3% of respondents undergoing such tests. This indicates a potential gap in healthcare practices, as serological tests can provide valuable diagnostic information for guiding wound management strategies. Increased awareness and promotion of serological tests among healthcare providers could lead to better wound care outcomes. Overall, the survey findings underscore the complexities and challenges associated with non-healing chronic wounds, especially in the context of diabetes-related wounds. The study highlights the need for comprehensive and personalized wound management strategies, increased awareness about wound-related serological tests, and the exploration of alternative treatment approaches to improve the outcomes and quality of life for individuals affected by chronic wounds. Addressing these challenges would lead to better wound healing outcomes, reduced healthcare burdens, and enhanced overall patient well-being Keywords: Non-healing chronic wounds, Wounds Prevalence, Antimicrobial therapy, Alternative treatment approaches, Serological tests.

Chronic wounds including pressure, venous, arterial and diabetic neuropathic ulcers, represent a significant burden to the healthcare system. These different chronic wound types do not share origin or cause, however they have common features as bacterial infection and continuing influx of polymorphonuclear neutrophils that release high concentrations of matrix metalloproteases (MMPs), myeloperoxidase (MPO) and reactive oxidative species causing excessive degradation of the extracellular matrix (ECM) and the growth factors. Because of the multifactorial nature of virtually all chronic wounds, the therapeutic wound healing approach should emphasize the necessity to investigate wound dressings that possess the ability to directly and indirectly modulate the biochemical environment based on the pathology of chronic to encourage the healing process. The overall aim of the present work was to develop biopolymer wound dressings capable to improve the management of chronic wounds. The specific research objective was defined in three main targets: i) to balance the proteolytic activity of MMPs, ii) to balance the MPO activity and the oxidative environment, and iii) antimicrobial protection. The first part of the thesis aimed to provide suitable materials to perform bioactive biopolymer-based wound dressings. The first step was to provide a versatile functionalization of chitosan platform to improve the sequestering ability over metal dependent enzymes (MMPs) in chronic wounds. In order to impart to chitosan the ability to inhibit MMP, chitosan was functionalized with deferent thiol moieties, which can chelate the zinc cation in the active site of the enzyme, modifying MMP activity. In addition the combination of -NH2 and -SH chemistry allowed grafting of other active agents on the chitosan platform. The second step was the identification and evaluation of natural active agents as chronic wound healing promoters. Polyphenols from bark, twigs and leaf extracts from the medicinal plant Hamamelis virginiana (Witch hazel) were studied for this porpoise and it was found to have both a strong antioxidant activity and an inhibitory effect on MPO and collagenase. The second part of the thesis was focused in the performance and evaluation of new materials for wound healing applications. To this aim, chitosan and/or thiolated chitosan were modified with H. virginiana extracts following different approaches. The first approach was focused to develop a new method for covalent functionalization of thiolated chitosan with polyphenols from H. virginiana extracts. The novelty of this approach consists in the use of thiolysis - a common analytical method for proanthocyanidins characterization - to covalently functionalize natural macromolecules such as chitosan with bioactive phenolic moieties. The phenolics-functionalized chitosan showed improved therapeutic properties in vitro. The second approach focused on the use of laccase-assisted cross-linking between phenolic moieties of H. virginiana with chitosan and gelatin as a functionalization method to obtain stable and bioactive hydrogel wound dressings. H. virginiana extract was oxidized by laccase in a one-step process under mild reaction conditions to covalently crosslink chitosan and gelatin. The physical and mechanical properties of these hydrogels were investigated using different analytical techniques and their potential for chronic wound treatment was evaluated in vitro in terms of antibacterial and inhibitory effect on MPO and collagenase. The results indicated that the polyphenols exerted a dual role in the hydrogel: i) "passive" being a structural element, and ii) "active" modifying the chronic wound environment by attenuating the deleterious MMPs, MPO and ROS activities, and reducing the bacterial load.

Biofilms in Chronic Wounds: Pathogenesis and Diagnosis

To evaluate the effects of hyperbaric oxygen (HBO) therapy in the management of chronic wound and observe the correlation between wound healing and CD34+ endothelial progenitor cells (EPCs). A total of 119 patients with chronic wound in lower extremities lasting > 3 months were recruited for this randomized, single-center, placebo-controlled clinical trial. The changes of CD34+ average count before and after HBO therapy were detected by flow cytometry (FACS). There were 97 patients on long-term HBO therapy and in 22 patients on hyperbaric air therapy as control group. The CD34/Scal-1+ and CD34/CXCR4 dual-positive populations of gated cell were determined respectively by FACs. The outcomes of two groups were compared. Treatment was administered within a single-place hyperbaric chamber for 90-min daily (session duration 120 min) for 5 days a week for 4 weeks (20 treatment sessions). The wound size decreased at the 4-week end point (62.7% ± 22.3% in the HBO group vs 34.4% ± 20.6% in the control group, P < 0.05). After 10 episodes of HBO therapies for chronic non-healing wound, the peripheral CD34+ EPCs average count rose from 0.24% ± 0.03% at pre-treatment to 1.32% ± 0.05% while the number was 1.75% ± 0.17% after 20 episodes of HBO (P < 0.05). Both were significantly different from that of the patients at pre-treatment. However the overall circulating white cell count was not significantly elevated. The CD34/Scal-1+ and CD34/CXCR4 dual-positive populations of gated cell in HBO group were 5.8 and 5.2 folds than those at pre-treatment respectively. The number of EPCs was positively correlated with wound healing in lower extremities (correlation coefficient 0.84; P < 0.01). Adjunctive treatment of HBO facilitates the healing of chronic non-healing wound in selected patients through the mobilization of EPCs.

We sought to examine whether vacuum-assisted closure (VAC) is associated with fewer surgical site infections (SSIs) or infections of chronic wounds than other management procedures for surgical wounds. The PubMed and Scopus databases were searched systematically. Randomized controlled trials (RCTs) comparing the development of SSIs or infections of chronic wounds between patients treated with VAC for acute or chronic wounds and those whose wounds were treated without VAC were considered eligible for inclusion in the study. Eight RCTs met the inclusion criteria for the study. Four of the studies included chronic or diabetic lower extremity wounds and four included fractures. In three of four studies reporting on fractures, the wounds were not closed post-operatively, whereas in one study primary closure of the wound was performed. With regard to wounds left open after the stabilization of fractures, patients whose wounds were treated with VAC developed fewer SSIs than those whose wounds were treated without VAC ([367 patients (196 with VAC; 171 without VAC) relative risk [RR], 0.47; 95% CI 0.28-0.81]). On the contrary, no difference in the development of SSIs occurred among patients with chronic or diabetic lower-extremity wounds treated with VAC and those whose wounds were treated without VAC ([638 patients (320 with VAC; 318 without VAC) RR 1.67; 95% CI: 0.71-3.94]). The available evidence suggests that the development of infections in wounds treated with VAC depends on the type of wound being treated.

Chronic wounds can be classified as diabetic foot ulcers, pressure ulcers, or venous leg ulcers. Chronic wound management has become a threat to clinicians and constitutes a major healthcare burden. The healing process of chronic wounds requires many factors to work in concert to achieve optimal healing. Various treatment options, ranging from hypoxia to infection, have evolved considerably to address the challenges associated with chronic wound healing. The conventional and accelerating treatments for chronic wounds still represent an unmet medical need due to the complex pathophysiology of the chronic wound microenvironment. In clinical settings, traditional chronic wound care practices rely on nonspecific topical treatment, which can reduce pain and alleviate disease progression with varying levels of success but fail to completely cure the wounds. Conventional wound dressings, such as hydrocolloids, gauze, foams, and films, have also shown limited success for the treatment of chronic wounds and only act as a physical barrier and absorb wound exudates. Emerging advances in treatment approaches, including novel therapies (stem cells, microRNAs, and nanocarrier-based delivery systems) and multifunctional biological dressings, have been reported for chronic wound repair. This review summarizes the challenges offered by chronic wounds and discusses recent advancements in chronic wound treatment.

Infection is the likeliest single cause of delayed healing in healing of chronic open wounds by secondary intention. If neglected it can progress from contamination to colonization and local infection through to systemic infection, sepsis and multiple organ dysfunction syndrome, and it can be life-threatening. Infection in chronic wounds is not as easy to define as in acute wounds, and is complicated by the presence of biofilms. There is, as yet, no diagnostic for biofilm presence, but it contributes to excessive inflammation - through excessive and prolonged stimulation of nitric oxide, inflammatory cytokines and free radicals - and activation of immune complexes and complement, leading to a delay in healing. Control of biofilm is a key part of chronic wound management. Maintenance debridement and use of topical antimicrobials (antiseptics) are more effective than antibiotics, which should be reserved for treating spreading local and systemic infection. The continuing rise of antimicrobial resistance to antibiotics should lead us to reserve their use for these indications, as no new effective antibiotics are in the research pipeline. Antiseptics are effective through many mechanisms of action, unlike antibiotics, which makes the development of resistance to them unlikely. There is little evidence to support the theoretical risk that antiseptics select resistant pathogens. However, the use of antiseptic dressings for preventing and managing biofilm and infection progression needs further research involving well-designed, randomized controlled trials.

Background: Chronic non-healing wounds are one of the major burden to the patients in the present era and covers about 1% of adult population and 3.6% of the population greater than 65 years. Chronic leg wounds are the common cause of morbidity and its prevalence in the community range from 1.9 to 13.1%. Indian studies show the prevalence of chronic wounds of around 4.5/1000 population. Recent studies have shown that application of a sub atmospheric pressure in a controlled manner to the wound site helps significantly in wound healing. Aim of the present study is to assess the efficacy of topical negative pressure moist wound dressings in wound healing process in chronic wounds and to prove that negative pressure dressings can be used as a much better treatment option than conventional saline dressings in the management of chronic wounds.Methods: After 10 days, in study group the mean rate of granulation tissue formation, mean graft, mean hospital stay was 81.7%,80.6%, 34.7 days respectively and the same in control group it is 41.9%. ,60.45%, 58.60 days respectively.Results: To conclude, topical negative pressure dressing’s help in faster healing of chronic wounds and better graft take up and reduces hospital stay of these patients.Conclusions: The database of our retrospective study regarding age and sex incidence, clinicopathological features and therapeutic outcome was comparable to other studies in various literatures.

Increased local temperature is a classic sign of wound infection, and its quantitative measurement has the potential to assist with assessment and diagnosis of chronic deep wound and surrounding skin infection at the bedside. Evidence supporting such use in chronic wound care is very limited. This clinical pilot study was conducted in an attempt to quantify the relationship between increased periwound skin temperature and wound infection, as well as validate use of a handheld infrared thermometer for the wound care practitioner. Using a cross-sectional design, 2 groups of participants were recruited from a chronic wound clinic: without wounds (n = 20) and with chronic leg ulcers (n = 40). Participant and wound characteristics were documented. All skin temperatures were documented using a handheld infrared thermometer under consistent environmental conditions within the clinic. Data analysis was based on the difference (Delta) in skin temperature (in degrees Fahrenheit) between a target or wound site and an equivalent contralateral control site. Wound infection was identified using the combination of a validated assessment tool and clinical judgment. Supplemental semiquantitative bacterial swabs were collected from all wounds. Descriptive statistics were analyzed using the chi-squared calculation. A Pearson r calculation of test-retest skin temperature data collected from nonwounded participants initially determined reliability of the infrared thermometer. Correlation of increased periwound skin temperature to wound infection was determined by calculation of a 1-way analysis of variance. The infrared thermometer was found to be reliable (r = 0.939, P = .000 at a 95% confidence interval). A statistically significant relationship between increased periwound skin temperature and wound infection was identified (F = 44.238, P = .000 at a 95% confidence interval). Neither patient nor wound characteristics were significantly different between the participants with noninfected or infected wounds. The results of this study demonstrate that incorporating quantitative skin temperature measurement into routine wound assessment provides a timely and reliable method for a wound care practitioner to quantify the heat associated with deep and surrounding skin infection and to monitor ongoing wound status. Study limitations may reduce transferability of these findings to wound types other than chronic leg ulcers. Further research is needed to support and strengthen these results.

Extracorporeal shockwave therapy (ESWT) has been shown to reduce wound dimensions and healing time in chronic wounds and should be considered a valuable tool in the healing of chronic complex lower extremity wounds. The aim of this small case series was to evaluate the effect of ESWT on complex chronic wounds in patients with multiple comorbidities in a medically underserved outpatient wound care clinic setting. All patients had baseline wound measurements taken. Pictures of the wounds were also taken at the time of the initial visit. Patients selected for ESWT received weekly treatments for a maximum recorded duration of 12 weeks in the form of focused electro-hydraulic acoustic pulses. Wound beds were cleansed according to standard of care. Thirteen patients were followed with a total of 18 wounds treated. After retrospectively analyzing the data, 3 subjects and a total of 5 wounds were excluded, leaving 10 total subjects and 13 wounds. Out of these wounds, 12 healed completely by or before week 12 of ESWT. All wounds demonstrated significant wound dimension reduction during the first 12 weeks of treatment. ESWT could offer accessible, fast, safe, and cost-effective management of some complex chronic wounds. Further research is needed to validate these findings.

The objectives of this research were 1) to study the properties of both scientific and traditional medicinal herbs to produce innovative herbal medicine for chronic wounds healing in diabetic patients, and 2) to analyze chronic wounds healing by innovative herbal medicine and Buddhist ways to prevent disability in 30 diabetic patients in Mahasarakham, Thailand. The results revealed that 19 medicinal herbs have properties in managing the blood, vascular, lymphatic system, the main cause of chronic wounds, reducing blood viscosity, purifying blood vessels, flushing out waste water, and healing wounds. 5 medicinal herbs were used to produce innovative herbal medicine, and Buddhist principles were used in research and for informants. Chronic wounds in diabetic patients have three characteristics: peripheral neuropathy, ischemic wounds, and infectious wounds. Herbal Oil Formula 1 and Herbal Infusion Formula 2 were used as basic medicines for healing, Herbal Capsule Formula 3 for inflamed wounds, Herbal Infusion for wounds with dark secretions and rotten blood. Wounds with a lot of secretions, foul odors, and full wounds were healed by Mangosteen Peel Powder Formula 5. Accordingly, 100% of all 3 types of chronic wounds were healed. This saved all patients from disability.

Tackling chronic wound healing using nanomaterials: advancements, challenges, and future perspectives

Combinatorial wound dressings loaded with synergistic antibiotics in the treatment of chronic infected wounds

Chronic wounds impose a significant healthcare burden to a broad patient population. Cell-based therapies, while having shown benefits for the treatment of chronic wounds, have not yet achieved widespread adoption into clinical practice. We developed a CRISPR/Cas9 approach to precisely edit murine dendritic cells to enhance their therapeutic potential for healing chronic wounds. Using single-cell RNA sequencing of tolerogenic dendritic cells, we identified N-myc downregulated gene 2 (Ndrg2), which marks a specific population of dendritic cell progenitors, as a promising target for CRISPR knockout. Ndrg2-knockout alters the transcriptomic profile of dendritic cells and preserves an immature cell state with a strong pro-angiogenic and regenerative capacity. We then incorporated our CRISPR-based cell engineering within a therapeutic hydrogel for in vivo cell delivery and developed an effective translational approach for dendritic cell-based immunotherapy that accelerated healing of full-thickness wounds in both non-diabetic and diabetic mouse models. These findings could open the door to future clinical trials using safe gene editing in dendritic cells for treating various types of chronic wounds.

While much is known about acute infection pathogenesis, the understanding of chronic infections has lagged. Here we sought to identify the genes and functions that mediate fitness of the pathogen Pseudomonas aeruginosa in chronic wound infections, and to better understand the selective environment in wounds. We found that clinical isolates from chronic human wounds were frequently defective in virulence functions and biofilm formation, and that many virulence and biofilm formation genes were not required for bacterial fitness in experimental mouse wounds. In contrast, genes involved in anaerobic growth, some metabolic and energy pathways, and membrane integrity were critical. Consistent with these findings, the fitness characteristics of some wound impaired-mutants could be represented by anaerobic, oxidative, and membrane-stress conditions ex vivo, and more comprehensively by high-density bacterial growth conditions, in the absence of a host. These data shed light on the bacterial functions needed in chronic wound infections, the nature of stresses applied to bacteria at chronic infection sites, and suggest therapeutic targets that might compromise wound infection pathogenesis.