Burn wound infections

Advancing burn wound treatment: exploring hydrogel as a transdermal drug delivery system

Burn injuries are prevalent and life-threatening forms that contribute significantly to mortality rates due to associated wound infections. The management of burn wounds presents substantial challenges. Hydrogel exhibits tremendous potential as an ideal alternative to traditional wound dressings such as gauze. This is primarily attributed to its three-dimensional (3D) crosslinked polymer network, which possesses a high water content, fostering a moist environment that supports effective burn wound healing. Additionally, hydrogel facilitates the penetration of loaded therapeutic agents throughout the wound surface, combating burn wound pathogens through the hydration effect and thereby enhancing the healing process. However, the presence of eschar formation on burn wounds obstructs the passive diffusion of therapeutics, impairing the efficacy of hydrogel as a wound dressing, particularly in cases of severe burns involving deeper tissue damage. This review focuses on exploring the potential of hydrogel as a carrier for transdermal drug delivery in burn wound treatment. Furthermore, strategies aimed at enhancing the transdermal delivery of therapeutic agents from hydrogel to optimize burn wound healing are also discussed.

Antivirulence and antipathogenic activity of Mayan herbal remedies against Pseudomonas aeruginosa

ETHNOPHARMACOLOGICAL RELEVANCE

The Yucatan Peninsula has a privileged wealth of vascular plants with which various Mayan herbal formulations have been developed. However, studies on their antipathogenic and antivirulence properties are scarce.

AIM OF THE STUDY

Identify antivirulence properties in Mayan herbal remedies and determine their antipathogenic capacity in burn wounds infected with Pseudomonas aeruginosa.

MATERIALS AND METHODS

An ethnobotanical study was conducted in Mayan communities in central and southern Quintana Roo, Mexico. Furthermore, the antipathogenic capacity of three Mayan herbal remedies was analyzed using an animal model of thermal damage and P. aeruginosa infection. Antivirulence properties were determined by inhibiting phenotypes regulated by quorum sensing (pyocyanin, biofilm, and swarming) and by the secretion of the ExoU toxin. The chemical composition of the most active herbal remedy was analyzed using molecular network analysis.

RESULTS

It was found that topical administration of the remedy called "herbal soap" (HS) for eleven days maintained 100% survival of the animals, reduced establishment of the bacteria in the burn and prevented its systemic dispersion. Although no curative effect was recorded on tissue damaged by HS treatment, its herbal composition strongly reduced swarming and ExoU secretion. Through analysis of Molecular Networks, it was possible to carry out a global study of its chemical components, and identify the family of oxindole monoterpenoid alkaloids and carboline and tetrahydropyrididole alkaloids. In addition, flavonols, flavan-3-ols, and quinic acid derivatives were detected.

CONCLUSIONS

The antipathogenic and antivirulence capacity of ancient Mayan remedies makes them a potential resource for developing new antibacterial therapies to treat burns infected by P. aeruginosa.

Nanofiber-reinforced self-healing polysaccharide-based hydrogel dressings for pH discoloration monitoring and treatment of infected wounds

The escalating global health concern arises from chronic wounds induced by bacterial infections, posing a significant threat to individuals. Consequently, an imperative exist for the development of hydrogel dressings to facilitate prompt wound monitoring and efficacious wound management. To this end, pH-sensitive bromothymol blue (BTB) and pH-responsive drug tetracycline hydrochloride (TH) were introduced into the polysaccharide-based hydrogel to realize the integration of wound monitoring and controlled treatment. Polysaccharide-based hydrogels were formed via a Schiff base reaction by cross-linking carboxymethyl chitosan (CMCS) on an oxidized sodium alginate (OSA) skeleton. BTB was used as a pH indicator to monitor wound infection through visual color changes visually. TH could be dynamically released through the pH response of the Schiff base bond to provide effective treatment and long-term antibacterial activity for chronically infected wounds. In addition, introducing polylactic acid nanofibers (PLA) enhanced the mechanical properties of hydrogels. The multifunctional hydrogel has excellent mechanical, self-healing, injectable, antibacterial properties and biocompatibility. Furthermore, the multifaceted hydrogel dressing under consideration exhibits noteworthy capabilities in fostering the healing process of chronically infected wounds. Consequently, the research contributes novel perspectives towards the advancement of intelligent and expeditious bacterial infection monitoring and dynamic treatment platforms.

Bloodstream infections and multidrug resistant bacteria acquisition among burns patients in Australia and New Zealand: A registry-based study

INTRODUCTION

This study interrogates infection related data in the Burns Registry of Australia and New Zealand (BRANZ), to examine associations of multi-drug resistant organisms (MDROs) and blood stream infection (BSI).

METHODS

Data between July 2016 and June 2021 were analysed to determine prevalence, risk factors and outcomes associated with BSIs and MDROs: Methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant Enterococcus (VRE), carbapenem-resistant Pseudomonas spp. (CRP), and carbapenem-resistant Enterobacter (CRE). Data completeness and value for quality improvement activity were assessed.

RESULTS

We found a low incidence (3.4%) of the resistant organisms of interest, and no change over the study period. Fequency varied between services and increased with age and size of burn. MRSA was the commonest organism in all age groups. A positive BSI result occurred in 1.6% of patients (12.1% of cultures taken) at a median time of 10.2 days post injury. Free text identification of organisms was inconsistently documented.

CONCLUSIONS

The low rate and patterns of acquisition of MDROs of interest and BSIs is comparable with reports from countries with low incidence of massive burns. Wider adoption of a standardized laboratory reporting framework would help realise the potential of clinical quality registries to provide data which supports evidence based infection prevention initiatives.

Assessing Pediatric Burn Wound Infection Using a Point-of-Care Fluorescence Imaging Device

Wound infection is the most common complication among pediatric burn patients. When not treated promptly, burn wound infection may lead to delayed healing, failure of skin grafts, or death. Standard burn wound assessment includes inspection for visual signs and symptoms of infection (VSSI) and microbial sampling. To aid in the assessment of burn wound infection, the MolecuLight, a point-of-care autofluorescence imaging device, was introduced at our pediatric burn program in 2020. The MolecuLight uses violet light to illuminate the wound bed, causing clinically relevant quantities of 29 different species of bacteria (>104 CFU/g) to fluoresce in real time. The objectives of this study were to evaluate the role of the MolecuLight in the management of pediatric burn wounds and determine if the findings from the MolecuLight corresponded to VSSI and/or microbial sampling. A retrospective review of patients 0-18 years who had burn wounds assessed with the MolecuLight between November 1, 2020 and June 8, 2023 was conducted. Data were extracted from the medical records of 178 eligible patients with 218 wounds imaged with the device. Fluorescence corresponded with VSSI in 81% of wounds and microbial findings in 82% of wounds. MolecuLight fluorescence, in combination with VSSI, improved sensitivity for detecting wound infections by 39% and decreased specificity by 19% compared to visual signs and symptoms in isolation. Incorporation of the MolecuLight in standard burn wound assessments can improve the detection of infections, which may promote improved wound healing outcomes and antimicrobial stewardship.

Distribution of Nosocomial Pathogens and Antimicrobial Resistance among Patients with Burn Injuries in China: A Comprehensive Research Synopsis and Meta-Analysis

INTRODUCTION

Over the past decade, numerous studies have described the types of pathogens and their antibiotic resistance patterns in patients with burn injuries in China; however, the findings have generally been inconsistent. We conducted a literature search and meta-analysis to summarize the infection spectra and antimicrobial resistance patterns in patients with burn injuries.

METHODS

We searched the PubMed, Embase, Web of Science, China National Knowledge Infrastructure, China Biomedical Literature, Wanfang, and Weipu databases for relevant articles published between January 2010 and December 2023. The DerSimonian-Laird random-effects model was used to estimate the proportions and 95% confidence intervals (CIs) of pathogens among Chinese patients with burn injuries. Meta-regression analyses were performed to explore differences in the proportions of pathogens among different subgroups and their resistance patterns. This study was registered with PROSPERO (CRD42024514386).

RESULTS

The database searches yielded 2017 records; after removing duplicates and conducting initial screening, 219 articles underwent full-text screening. Ultimately, 60 studies comprising a total of 62,819 isolated strains reported the proportions of pathogens in patients with burn injuries and were included in this meta-analysis. Meta-analyses were conducted on 18 types of pathogens. The most common pathogens causing infections in Chinese patients with burn injuries were Staphylococcus aureus, Pseudomonas aeruginosa, Acinetobacter baumannii, Klebsiella pneumoniae, and Staphylococcus epidermidis. Similar results were observed in the subgroup analysis focusing on wound infections. Since 2015, there has been a significant decrease in the proportion of Pseudomonas aeruginosa (R2 = 4.89%) and a significant increase in the proportion of Klebsiella pneumoniae (R2 = 9.60%). In terms of antibiotic resistance, there has been a significant decrease in the resistance of Staphylococcus aureus to multiple antibiotics and an increasing trend in the resistance of Klebsiella pneumoniae.

CONCLUSIONS

We systematically summarized the epidemiological characteristics and antibiotic resistance patterns of pathogens among individuals suffering from burns in China, thus providing guidance for controlling wound infections and promoting optimal empirical antimicrobial therapy. The observed high levels of antibiotic resistance underscore the need for ongoing monitoring of antibiotic usage trends.

Personalized bacteriophage therapy outcomes for 100 consecutive cases: a multicentre, multinational, retrospective observational study

In contrast to the many reports of successful real-world cases of personalized bacteriophage therapy (BT), randomized controlled trials of non-personalized bacteriophage products have not produced the expected results. Here we present the outcomes of a retrospective observational analysis of the first 100 consecutive cases of personalized BT of difficult-to-treat infections facilitated by a Belgian consortium in 35 hospitals, 29 cities and 12 countries during the period from 1 January 2008 to 30 April 2022. We assessed how often personalized BT produced a positive clinical outcome (general efficacy) and performed a regression analysis to identify functional relationships. The most common indications were lower respiratory tract, skin and soft tissue, and bone infections, and involved combinations of 26 bacteriophages and 6 defined bacteriophage cocktails, individually selected and sometimes pre-adapted to target the causative bacterial pathogens. Clinical improvement and eradication of the targeted bacteria were reported for 77.2% and 61.3% of infections, respectively. In our dataset of 100 cases, eradication was 70% less probable when no concomitant antibiotics were used (odds ratio = 0.3; 95% confidence interval = 0.127-0.749). In vivo selection of bacteriophage resistance and in vitro bacteriophage-antibiotic synergy were documented in 43.8% (7/16 patients) and 90% (9/10) of evaluated patients, respectively. We observed a combination of antibiotic re-sensitization and reduced virulence in bacteriophage-resistant bacterial isolates that emerged during BT. Bacteriophage immune neutralization was observed in 38.5% (5/13) of screened patients. Fifteen adverse events were reported, including seven non-serious adverse drug reactions suspected to be linked to BT. While our analysis is limited by the uncontrolled nature of these data, it indicates that BT can be effective in combination with antibiotics and can inform the design of future controlled clinical trials. BT100 study, ClinicalTrials.gov registration: NCT05498363 .

In vitro analysis of interactions between Pseudomonas aeruginosa and Candida albicans treated with silver sulfadiazine in wound infections

Background

Microorganisms tend to rely on close relationships with other species to survive. Consequently, biofilms formed by interactions of different species have been shown to delay the wound healing process. Studies suggest these mixed-population infections contribute to the development of drug resistance and inhibition of host immune response. Silver sulfadiazine (SSD) has been shown to effectively decrease the risk of infection in an open wound. Typically, these are bacterial wound infections; however, the role of fungal species needs further attention.

Objectives

The purpose of this in vitro study was to determine the effect of SSD on interactions between Pseudomonas aeruginosa 09-009 (PA1) or P. aeruginosa 09-010 (PA2) and Candida albicans ATTC 64550 (CA).

Methods

A mixture of 4 mL of tryptic soy broth (TSB) and 100 µL of CA and/or PA1 or PA2 (∼106 log cfu/mL) inoculums were deposited into either wells or vials. The wells or vials were then sonicated (50 W for 10 s) to separate microorganisms attached to the walls. After incubation, cell counts were performed at 24 and 48 h for each microorganism using specific media.

Results

Our results show that without SSD treatment, P. aeruginosa exhibits an inhibitory effect on C. albicans. Treatment with SSD demonstrated significant reduction of P. aeruginosa; however, C. albicans persisted. This experiment demonstrates that SSD was effective in reducing the bioburden of both P. aeruginosa strains after 24 and 48 h; however, it was not as effective in reducing C. albicans.

Conclusions

The data suggest that for polymicrobial mixed infections containing Pseudomonas spp. and C. albicans, treatment with SSD may be beneficial but does not provide adequate microorganism eradication. As such, added treatments that provide coverage for Candida infection are necessary. Additional in vivo studies are needed to obtain a better understanding of the complex interactions between these organisms.

Cold atmospheric plasma is bactericidal to wound-relevant pathogens and is compatible with burn wound healing

Burn wound healing can be significantly delayed by infection leading to increased morbidity and hypertrophic scarring. An optimal antimicrobial agent would have the ability to kill bacteria without negatively affecting the host skin cells that are required for healing. Currently available products provide antimicrobial coverage, but may also cause reductions in cell proliferation and migration. Cold atmospheric plasma is a partially ionized gas that can be produced under atmospheric pressure at room temperature. In this study a novel handheld Aceso Plasma Generator was used to produce and test Aceso Cold Plasma (ACP) in vitro and in vivo. ACP showed a potent ability to eliminate bacterial load in vitro for a number of different species. Deep partial-thickness and full-thickness wounds that were treated with ACP after burning, after excision, after autografting, and at days 5, 7, and 9 did not show any negative effects on their wound healing trajectories. On par with in vitro analysis, bioburden was decreased in treated wounds vs. control. In addition, metrics of hypertrophic scar such as dyschromia, elasticity, trans-epidermal water loss (TEWL), and epidermal and dermal thickness were the same between the two treatment groups.It is likely that ACP can be used to mitigate the risk of bacterial infection during the phase of acute burn injury while patients await surgery for definitive closure. It may also be useful in treating wounds with delayed re-epithelialization that are at risk for infection and hypertrophic scarring. A handheld cold plasma device will be useful in treating all manner of wounds and surgical sites in order to decrease bacterial burden in an efficient and highly effective manner without compromising wound healing.

Metal-ion-controlled hydrogel dressing with enhanced adhesive and antibacterial properties for accelerated wound healing

In order to improve the wound repair environment, this research has successfully developed a new multifunctional hydrogel dressing, which has strong adaptability and can accelerate wound healing. Pioneering the development of metal-ion-controlled hydrogel dressings, this research integrates dopamine and imidazole double crosslinked networks with metal-ion coordination. The resulting hydrogel dressing exhibits a notable antibacterial effect and exceptional mechanical properties, withstanding pressures of up to 12 kPa, tensions of 25 kPa, and maintaining skin adhesion at 6 kPa. Furthermore, the dressing can self-heal within only 7-8 s post-injection. Impressively, the hydrogel achieves complete biodegradation within a short timeframe (37 h). Notably, the use of various metal ions facilitates painless peeling during the degradation period, perfectly aligning with the requirements of an ideal wound dressing. This study has made significant progress in the fields of trauma repair and materials, providing strong solutions for dealing with harsh post-traumatic environments.

Multi-resistant organisms in burn patients: an end or a new beginning

Infections are a major cause of morbidity and mortality in burn patients, and the rise of multidrug-resistant organisms (MDROs) has made it more challenging to manage and prevent infections. This review examines the available treatment options for MDROs in burn patients and anticipates the future challenges posed by their increasing prevalence. The review covers new antibiotics, such as Eravacycline and Plazomicin, as well as non-antibiotic therapies, such as bacteriophages and nanoparticles. Future research should focus on examining the long-term efficacy, cost-effectiveness, and in vivo efficacy of different treatment modalities. The potential of alternative therapies, such as probiotics and low-frequency magnetic fields, should also be explored. Accurate and rapid diagnostic and monitoring tools for detecting MDROs in burn patients should be developed. The emergence of MDROs in burn care is a challenge and a new beginning in infection innovation and novel treatments.

Design and Application of an In Situ Traceable Nitric Oxide Donor for Promoting the Healing of Wound Infections

Therapies for wound infections require medications with antibacterial and wound-healing functions. However, it remains a challenge to produce a single drug that can perform dual functions. Nitric oxide (NO), with its antibacterial and wound-healing activities, is an ideal solution to address this challenge. However, many controlled-release strategies for NO rely on external probes for tracing the release in situ, making it difficult to precisely assess the location and magnitude. To address this issue, this study describes a novel NO donor, DHU-NO1, capable of efficiently releasing NO under mild conditions (450 nm illumination). Simultaneously, DHU-NO1 generates the fluorophore Azure B (AZB), which enables direct, non-consumptive tracing of the NO release by monitoring the fluorescence and absorption changes in AZB. Given that NO can be conveniently traced, the amount of released NO can be controlled during biological applications, thereby allowing both functions of NO to be performed. When applied to the affected area, DHU-NO1, illuminated by both a simple light-emitting diode (LED) light source and natural light, achieves significant antibacterial effects against wound infections and promotes wound healing in mice. This study offers a novel and effective approach for treating wound infections.

Current Knowledge and Perspectives of Phage Therapy for Combating Refractory Wound Infections

Wound infection is one of the most important factors affecting wound healing, so its effective control is critical to promote the process of wound healing. However, with the increasing prevalence of multi-drug-resistant (MDR) bacterial strains, the prevention and treatment of wound infections are now more challenging, imposing heavy medical and financial burdens on patients. Furthermore, the diminishing effectiveness of conventional antimicrobials and the declining research on new antibiotics necessitate the urgent exploration of alternative treatments for wound infections. Recently, phage therapy has been revitalized as a promising strategy to address the challenges posed by bacterial infections in the era of antibiotic resistance. The use of phage therapy in treating infectious diseases has demonstrated positive results. This review provides an overview of the mechanisms, characteristics, and delivery methods of phage therapy for combating pathogenic bacteria. Then, we focus on the clinical application of various phage therapies in managing refractory wound infections, such as diabetic foot infections, as well as traumatic, surgical, and burn wound infections. Additionally, an analysis of the potential obstacles and challenges of phage therapy in clinical practice is presented, along with corresponding strategies for addressing these issues. This review serves to enhance our understanding of phage therapy and provides innovative avenues for addressing refractory infections in wound healing.

Fermented Polyherbal Formulation Ameliorates the Severity of Acute Multiple Antibiotics-Resistant Pseudomonas aeruginosa-Infected Burn Wound in a Rat Burn Model

Pseudomonas aeruginosa, a Gram-negative opportunistic bacterium, has emerged as a cause of life-threatening infections in burn wounds. Current therapeutic approaches through wound dressings and systemic medicines are far from satisfactory; resistance to more than two antibiotics shown by pathogens contributes to failures of therapy causing mortality. This animal study was conducted to check the efficacy of one Ayurveda-based fermented polyherbal preparation (AP 01) against multiple antibiotics-resistant (MAR) P. aeruginosa HW01-infected rat burn wounds. AP-01 was applied on artificially infected burn wound on a rat model infected with MAR P. aeruginosa to register the healing effects in terms of reduction in residual wound area percentage, the presence of C-reactive protein in blood, and the presence of viable bacteria colony. Topical application with conventional antibiotics served as a positive control. The polyherbal preparation had reduced the infected residual burn wound area at 40.63% ± 0.69 from the initial burn wound area within two weeks after a single intervention, whereas residual burn wound area remained much higher in the case of animals left untreated and in the case of the animals treated with control drug. Restoration to the normalcy of serum C-reactive protein level was also achieved earlier in the case of polyherbal AP-01-treated groups than in other groups. Fermented formulations using components of AP-01 singly or in different combinations had never been tested earlier for topical application in infected burn wound. The formulation of AP-01 was found superior in terms of the rate of healing and control of infection by MAR P. aeruginosa strains in burn wounds in rat models.

Plasma-derived Extracellular Vesicles (EVs) as Biomarkers of Sepsis in Burn Patients via Label-free Raman Spectroscopy

Sepsis following burn trauma is a global complication with high mortality, with ~60% of burn patient deaths resulting from infectious complications. Sepsis diagnosis is complicated by confounding clinical manifestations of the burn injury, and current biomarkers markers lack the sensitivity and specificity required for prompt treatment. Circulating extracellular vesicles (EVs) from patient liquid biopsy as biomarkers of sepsis due to their release by pathogens from bacterial biofilms and roles in subsequent immune response. This study applies Raman spectroscopy to patient plasma derived EVs for rapid, sensitive, and specific detection of sepsis in burn patients, achieving 97.5% sensitivity and 90.0% specificity. Furthermore, spectral differences between septic and non-septic burn patient EVs could be traced to specific glycoconjugates of bacterial strains associated with sepsis morbidity. This work illustrates the potential application of EVs as biomarkers in clinical burn trauma care, and establishes Raman analysis as a fast, label-free method to specifically identify features of bacterial EVs relevant to infection amongst the host background.

High-Intensity Blue Light (450-460 nm) Phototherapy for Pseudomonas aeruginosa-Infected Wounds

Background: Nosocomial wound infection with Pseudomonas aeruginosa (PA) is a serious complication often responsible for the septic mortality of burn patients. Objective: High-intensity antimicrobial blue light (aBL) treatment may represent an alternative therapy for PA infections and will be investigated in this study. Methods: Antibacterial effects of a light-emitting diode array (450-460 nm; 300 mW/cm2; 15/30 min; 270/540 J/cm2) against PA were determined by suspension assay, biofilm assay, and a human skin wound model and compared with 15-min topically applied 3% citric acid (CA) and wound irrigation solution (Prontosan®; PRT). Results: aBL reduced the bacterial number [2.51-3.56 log10 colony-forming unit (CFU)/mL], whereas PRT or CA treatment achieved a 4.64 or 6.60 log10 CFU/mL reduction in suspension assays. aBL reduced biofilm formation by 60-66%. PRT or CA treatment showed reductions by 25% or 13%. Here, aBL reduced bacterial number in biofilms (1.30-1.64 log10 CFU), but to a lower extend than PRT (2.41 log10 CFU) or CA (2.48 log10 CFU). In the wound skin model, aBL (2.21-2.33 log10 CFU) showed a bacterial reduction of the same magnitude as PRT (2.26 log10 CFU) and CA (2.30 log10 CFU). Conclusions: aBL showed a significant antibacterial efficacy against PA and biofilm formation in a short time. However, a clinical application of aBL in wound therapy requires effective active skin cooling and eye protection, which in turn may limit clinical implementation.

Early ambulation impacts on quality-of-life outcomes positively after lower limb burn injury: A group trajectory analysis

INTRODUCTION

Despite the challenges of providing burn care throughout the 2.5MKm2 jurisdiction of Western Australia, early intervention after injury remains a key premise of the multidisciplinary model of care applied by the State Adult Burn Unit (SABU) team. In particular, contemporary guidelines support the facilitation of early ambulation after lower limb burn and skin grafting. Thus, this study aimed to evaluate the association between the timing of ambulation after burn and surgery on quality of life (QoL) outcomes.

METHODS

Data from 1707 lower limb burn patients aged ≥ 18, admitted to the SABU between February 2011- December 2019, were included. Self-reported QoL longitudinal outcomes were assessed using the Short Form 36 and Burn Specific Health Scale Brief. Three recovery trajectories were defined according to their QoL outcome responses, mapped out to one year. Early ambulation was defined as occurring within 48 h of acute burn or surgery, as per SABU routine practice.

RESULTS

Early ambulation was shown to have a positive association to the higher QoL trajectory group (>75% of cohort), though not statistically significant for the Physical Component (PCS) and Mental health Component (MCS) summary scores of the SF36; however, ambulation pathway was associated with adjusted long-term BSHS-B QoL outcomes. The least favorable trajectory of long-term recovery of the physical aspects of QoL was seen in those with higher TBSA and complications and increasing age and comorbidities. In contrast, the mental health components of QoL were robust to all those factors, apart from pre-existing comorbidities.

CONCLUSION

Early ambulation after lower limb burn, and surgery, was positively associated with early and long-term QoL outcomes. Recovery trajectory is strongly indicated by where the patient journey begins after early acute care. The optimal physical QoL recovery trajectory was shared by those who were younger with reduced TBSA; complications; and, comorbidities whereas the mental health QoL trajectories were only impacted by comorbidities.

Microbial infections in burn patients

Polymicrobial infections are the leading causes of complications incurred from injuries that burn patients develop. Such patients admitted to the hospital have a high risk of developing hospital-acquired infections, with longer patient stays leading to increased chances of acquiring such drug-resistant infections. Acinetobacter baumannii, Klebsiella pneumoniae, Pseudomonas aeruginosa, and Proteus mirabilis are the most common multidrug-resistant (MDR) Gram-negative bacteria identified in burn wound infections (BWIs). BWIs caused by viruses, like Herpes Simplex and Varicella Zoster, and fungi-like Candida spp. appear to occur occasionally. However, the preponderance of infection by opportunistic pathogens is very high in burn patients. Variations in the causative agents of BWIs are due to differences in geographic location and infection control measures. Overall, burn injuries are characterized by elevated serum cytokine levels, systemic immune response, and immunosuppression. Hence, early detection and treatment can accelerate the wound-healing process and reduce the risk of further infections at the site of injury. A multidisciplinary collaboration between burn surgeons and infectious disease specialists is also needed to properly monitor antibiotic resistance in BWI pathogens, help check the super-spread of MDR pathogens, and improve treatment outcomes as a result.

Clinical impact of fungal colonization of burn wounds in patients hospitalized in the intensive care unit: a retrospective cohort study

Background

Invasive fungal infections in burn victims significantly increase mortality and hospitalization. The effect of fungal burn wound colonization has not been established.

Methods

All adult patients hospitalized in the intensive care unit (ICU) with burns ≥10% of total body surface area (TBSA) between 2005 and 2021 were included. Superficial swabs were collected whenever clinical suspicion of wound colonization was raised, and deep tissue samples were sent at any wound excision. The primary outcome was the incidence of invasive fungal infections defined as any deep tissue fungal infection or fungemia.

Results

Of 242 patients included, 39 (16.1%) had fungal wound colonization, 22 (56.4%) with yeasts and 24 (61.5%) molds. Patients with fungal colonization had a significantly higher rate of invasive fungal infections (82.1% vs 3.9%, p<0.001), candidemia (15.4% vs 3.4%, p=0.002), as well as longer ICU stay (61.5±57.6 vs 19±40.5 days, p<0.001), and higher in-ICU mortality (43.6% vs 15.8%, p<0.001). Survival analysis showed fungal colonization to be associated with significantly increased risk of invasive infection (aHR 25, 95% CI (9.67 to 64.62)), even when adjusted for age, TBSA, sequential organ failure assessment scores, Charlson Comorbidity Index and the presence of bacteremia.

Conclusions

Fungal burn wound colonization is associated with increased risk of invasive fungal infections and mortality.

Level of Evidence

This a single center, retrospective cohort study.

Rare multi-fungal sepsis: a case of triple-impact immunoparalysis

Patients with burn injury and inhalation injury are highly susceptible to infectious complications, including opportunistic pathogens, due to the loss of skin cover and mucosal damage of respiratory tract as well as the disruption of homeostasis. This case report, a 34-year-old man suffered critical burns, provides the first literature description of triple-impact immunoparalysis (critical burns, inhalation injury, and SARS-CoV-2 infection), leading to a lethal multifocal infection caused by several fungi including very rare environmental representatives Metschnikowia pulcherrima and Wickerhamomyces anomalus. The co-infection by these common environmental yeasts in a human is unique and has not yet been described in the literature. Importantly, our patient developed refractory septic shock and died despite targeted antifungal therapy including the most potent current antifungal agent-isavuconazole. It can be assumed that besides immunoparalysis, effectiveness of therapy by isavuconazole was impaired by the large distribution volume in this case. As this is a common situation in intensive care patients, routine monitoring of plasmatic concentration of isavuconazole can be helpful in personalization of the treatment and dose optimization. Whatmore, many fungal species often remain underdiagnosed during infectious complications, which could be prevented by implementation of new methods, such as next-generation sequencing, into clinical practice.

Microneedle Patch for Transdermal Sequential Delivery of KGF-2 and aFGF to Enhance Burn Wound Therapy

Severe burn wounds usually destroy key cells' functions of the skin resulting in delayed re-epithelization and wound regeneration. Promoting key cells' activities is crucial for burn wound repair. It is well known that keratinocyte growth factor-2 (KGF-2) participates in the proliferation and morphogenesis of epithelial cells while acidic fibroblast growth factor (aFGF) is a key mediator for fibroblast and endothelial cell growth and differentiation. However, thick eschar and the harsh environment of a burn wound often decrease the delivery efficiency of fibroblast growth factor (FGF) to the wound site. Therefore, herein a novel microneedle patch for sequential transdermal delivery of KGF-2 and aFGF is fabricated to enhance burn wound therapy. aFGF is first loaded in the nanoparticle (NPaFGF) and then encapsulated NPaFGF with KGF-2 in the microneedle patch (KGF-2/NPaFGF@MN). The result shows that KGF-2/NPaFGF@MN can successfully get across the eschar and sequentially release KGF-2 and aFGF. Additional data demonstrated that KGF-2/NPaFGF@MN achieved a quicker wound closure rate with reduced necrotic tissues, faster re-epithelialization, enhanced collagen deposition, and increased neo-vascularization. Further evidence suggests that improved wound healing is regulated by significantly elevated expressions of hypoxia-inducible factor-1 alpha (HIF-1ɑ) and heat shock protein 90 (Hsp90) in burn wounds. All these data proved that KGF-2/NPaFGF@MN is an effective treatment for wound healing of burns.

Microneedle System with Biomarker-Activatable Chromophore as Both Optical Imaging Probe and Anti-bacterial Agent for Combination Therapy of Bacterial-Infected Wounds and Outcome Monitoring

Wounds infected with bacteria, if left untreated, have the potential to escalate into life-threatening conditions, such as sepsis, which is characterized by widespread inflammation and organ damage. A comprehensive approach to treating bacterial-infected wounds, encompassing the control of bacterial infection, biofilm eradication, and inflammation regulation, holds significant importance. Herein, a microneedle (MN) patch (FM@ST MN) has been developed, with silk fibroin (SF) and tannic acid-based hydrogel serving as the matrix. Encapsulated within the MNs are the AIEgen-based activatable probe (FQ-H2O2) and the NLRP3 inhibitor MCC950, serving as the optical reporter/antibacterial agent and the inflammation regulator, respectively. When applied onto bacterial-infected wounds, the MNs in FM@ST MN penetrate bacterial biofilms and gradually degrade, releasing FQ-H2O2 and MCC950. The released FQ-H2O2 responds to endogenously overexpressed reactive oxygen species (H2O2) at the wound site, generating a chromophore FQ-OH which emits noticeable NIR-II fluorescence and optoacoustic signals, enabling real-time imaging for outcome monitoring; and this chromophore also exhibits potent antibacterial capability due to its dual positive charges and shows negligible antibacterial resistance. However, the NLRP3 inhibitor MCC950, upon release, suppresses the activation of NLRP3 inflammasomes, thereby mitigating the inflammation triggered by bacterial infections and facilitating wound healing. Furthermore, SF in FM@ST MN aids in tissue repair and regeneration by promoting the proliferation of epidermal cells and fibroblasts and collagen synthesis. This MN system, free from antibiotics, holds promise as a solution for treating and monitoring bacterially infected wounds without the associated risk of antimicrobial resistance.

Epidemiology and early bacterial colonization of minor and moderate pediatric burns: A retrospective study from a developing country

OBJECTIVES

Infection is still the leading cause of morbidity and mortality among burn patients worldwide. Isolation and identification of pediatric burn wound bacterial colonizers can prevent infection and improve burn trauma treatment. In this study, we explored early microbial colonizers within the burn wounds and the susceptibility of those isolates to antibiotics among hospitalized pediatric patients with minor and moderate burns, clinically significant infections and outcomes.

METHODS

A retrospective analysis of pediatric patients admitted to the inpatient pediatric surgical ward and treated for minor and moderate burns from 2009 to 2018 was performed.

RESULTS

One hundred six patients met the inclusion criteria. The mean age was 3.6 ± three years (0.2-14.1 years). The most common type of burn was scald burns (82.1%). The mean TBSA of the hospitalized pediatric burn cases was 8.5% (IQR, 6-12%). Seventy-nine (74.5%) patients had positive wound cultures at admission, regardless of the hospital admission day. Fifty-eight (73.4%) had one bacterial growth (mono isolate), while 21 (26.6%) had mixed growth or poly isolates. Among patients with mixed growth or poly isolate, 16 had two bacteria, three had three bacteria, and one had four bacteria isolated, totaling 105 isolated microorganisms (14 different species, 70.5% Gram-positive bacteria and 29.5% Gram-negative bacteria). Twelve patients (11%) developed clinically significant infections (eleven got burn wound infection, and one had septicemia). All patients received prophylactic systemic antibiotics. Only 35.2% of the isolated bacteria from the wounds were sensitive to the prophylactic antibiotics, and only ∼17% in case of clinically significant infections. We found a statistically significant difference in the length of hospital stay between patients with initially colonized samples of burn wounds compared with patients with initial negative samples (p = 0.008). All patients in the cohort survived hospital discharge.

CONCLUSION

Despite common bacterial colonization of acute burn wounds, only ∼10% of the patients developed clinically significant infections, a minority of which were sensitive to prophylactic antibiotics. Our findings indicate the need to refine the antibiotic approach in pediatric patients with minor/moderate burns in our local setting.

Multidrug-Resistant Pathogens in Wound Infections: A Systematic Review

This systematic review aimed to explore the antimicrobial activity of a silver-containing gelling fiber dressing against multidrug-resistant organisms (MDROs) in wound infections. It particularly focuses on burn wounds and evaluates its potential clinical significance in combating antimicrobial resistance. A comprehensive literature search was conducted across multiple databases over the past ten years. It is used to identify relevant studies addressing MDRO infections in wound care and exploring novel antimicrobial approaches. The included studies underwent rigorous methodological assessment. Additionally, the data were synthesized to evaluate the efficacy of silver-containing dressings in inhibiting MDRO growth and eradicating biofilm-associated bacteria. Moreover, this review revealed that silver-containing dressings have constant in vitro antimicrobial activity against 10 MDROs over seven days in simulated wound fluid. However, inhibitory and bactericidal effects were consistently observed against free-living and biofilm phenotypes. The findings suggest potential clinical significance in managing MDRO infections in wounds. This highlights its role in mitigating treatment failure and antimicrobial resistance. Despite the promising implications for wound management practices, this study acknowledges some limitations. In vitro models and the absence of direct clinical validation have also been included. However, the review explains the importance of new approaches. Nanotechnology has been used to address antimicrobial resistance in wound care. Thus, further research and innovation are needed to improve patient outcomes and combat antimicrobial resistance.

Complications Following Tissue Expander-Based Reconstruction in Pediatric Burn Injuries: A Retrospective Analysis

BACKGROUND

Tissue expansion has been widely used to reconstruct soft tissue defects following burn injuries in pediatric patients, allowing for satisfactory cosmetic and functional outcomes. Factors impacting the success of tissue expander (TE)-based reconstruction in these patients are poorly understood. Herein, we aim to determine the risk factors for postoperative complications following TE-based reconstruction in pediatric burn patients.

METHODS

A retrospective review of pediatric patients who underwent TE placement for burn reconstruction from 2006 to 2019 was performed. Primary outcomes were major complications (TE explantation, extrusion, replacement, flap necrosis, unplanned reoperation, readmission) and wound complications (surgical site infection and wound dehiscence). Descriptive statistics were calculated. The association between primary outcomes, patient demographics, burn characteristics, and TE characteristics was assessed using the chi-squared, Fisher's exact, and Mann-Whitney U tests.

RESULTS

Of 28 patients included in the study, the median [interquartile range (IQR)] age was 6.5 (3.3-11.8) years, with a follow-up of 12 (7-32) months. The majority were males [n = 20 (71%)], Black patients [n = 11 (39%)], and experienced burns due to flames [n = 78 (29%)]. Eleven (39%) patients experienced major complications, most commonly TE premature explantation [n = 6 (21%)]. Patients who experienced major complications, compared to those who did not, had a significantly greater median (IQR) % total body surface area (TBSA) [38 (27-52), 10 (5-19), P = 0.002] and number of TEs inserted [2 (2-3), 1 (1-2), P = 0.01]. Ten (36%) patients experienced wound complications, most commonly surgical site infection following TE placement [n = 6 (21%)]. Patients who experienced wound complications, compared to those who did not, had a significantly greater median (IQR) %TBSA [35 (18-45), 19 (13-24), P = 0.02].

CONCLUSION

Pediatric burn injuries involving greater than 30% TBSA and necessitating an increasing number of TEs were associated with worse postoperative complications following TE-based reconstruction.

Prevention and Management of Wound Infections in Burn Patients

The leading cause of morbidity in burn patients is infection with pneumonia, urinary tract infection, cellulitis, and wound infection being the most common cause. High mortality is due to the immunocompromised status of patients and abundance of multidrug-resistant organisms in burn units. Despite the criteria set forth by American Association of Burn, the diagnosis and treatment of burn infections are not always straightforward. Topical antimicrobials, isolation, hygiene, and personal protective equipment are common preventive measures. Additionally medical and nutritional optimization of the patients is crucial to reverse the immunocompromised status triggered by burn injury.

Wound infection among children with moderate burns - An explorative review of the association between reported frequency and diagnosis

INTRODUCTION

The Linkoping burn centre in Sweden has, even though being a high income country, reported high burn wound infections (BWI) frequencies in scalded children compared to similar populations in other parts of the world.

AIM

The aim was to investigate possible explanations for differences in frequency of BWI among children with partial thickness burns treated at the Linköping burn centre in Sweden, and that reported in other studies.

METHOD

In order to investigate what BWI criteria that were used in similar studies a literature search on PubMed Central was done along with a retrospective analysis of children previously diagnosed as infected to confirm or reject the high infection frequency reported earlier.

RESULT

Of the 34 selected publications reporting on BWI frequency 16 (47%) did not define a criteria for the BWI diagnosis and almost a third did not report on wound culturing. Of those who did report the use a third do not mention any bacterial growth found is these cultures. The retrospective analysis on children at the centre did not show any decrease in infection frequency even with some disagreement on onset for the BWI.

CONCLUSION

The reporting of criteria and diagnosis of burn wound infection is highly variable making it difficult to interpret results and come to conclusions. The high frequency of BWI at the centre might be a result of close monitoring due to study participation, use of clean instead of sterile routine at dressing changes or low thresholds for the diagnosis in respect to changes in infection markers.

Angioinvasive mucormycosis in burn intensive care units: A case report and review of literature

BACKGROUND

Mucormycosis is a rare, rapidly progressive and often fatal fungal infection. The rarity of the condition lends itself to unfamiliarity, delayed treatment, and poor outcomes. Diagnosis of fungal infections early enough to enable appropriate treatment occurs in less than half of affected patients.

CASE SUMMARY

An 11-year-old girl with a history of 15% total body surface area scald burns involving both lower limbs progressed to develop angioinvasive mucormycosis. This further led to a thrombosis of the right external iliac artery and vein and rapidly progressive necrosis of surrounding soft tissues. She also had dextrocardia and patent foramen ovale. A right hip disarticulation and serial aggressive debridements were performed but she went on to develop systemic sepsis with multisystem involvement and succumbed to the infection. Pathology revealed mucor species with extensive vascular invasion.

CONCLUSION

This case highlights the importance of maintaining vigilance for mycotic infections and acting appropriately when there are signs of fulminant wound infection.

Fusariosis in burn patients: A systematic review of case reports

Burns can cause skin damage, facilitating the entry of fungi and other microorganisms into the body, leading to infections. Fusarium is a fungus capable of infecting individuals with burn injuries. Diagnosing and treating Fusarium infections in burn patients can be challenging due to the manifestation of nonspecific symptoms. This study aims to investigate case reports and case series from published literature describing Fusarium infection in burned patients, in order to assess treatment regimens, clinical outcomes, and make recommendations for future management. We conducted searches on Web of Science, PubMed, ScienceDirect, and Medline for all case reports and case series containing keywords 'Burn', 'Burns', 'Burned', 'Fusarium', or 'Fusariosis' in the title or abstract. All burn patients who developed Fusarium fungal infections between January 1974 and March 2023 were included in the study. Demographic and clinical data were analyzed retrospectivity. The final analysis incorporates 24 case reports encompassing a total of 87 burn patients with Fusarium infection. Patient ages ranged from one to 85 years, with the majority being male (53%). The median percentage of burn surface area was 78%, and the skin in the face, upper limbs, and lower limbs were the most commonly infected sites. Fungal infections appeared around 10 days after the burn injury on average. The majority of the patients were identified through culture or histopathology. The Fusarium dimerum species complex, which was found in nine patients, was the most frequently identified Fusarium species complex. Amphotericin B was the most preferred treatment drug, followed by voriconazole, and 62% of patients underwent debridement. In our study, 23 patients (37%) died from fungal infections. Implementing early and effective treatment protocols targeting Fusarium spp. in burn treatment units can significantly reduce mortality rates. It is critical to enhance the understanding of fusariosis epidemiology and emphasize the importance of maintaining a high clinical suspicion for this condition in burn patients.

Prevalence and antimicrobial-resistant patterns of Pseudomonas aeruginosa among burn patients attending Yekatit 12 Hospital Medical College in Addis Ababa, Ethiopia

BACKGROUND

Burns are one of the most common forms of trauma globally. P. aeruginosa plays a prominent role as an etiological agent among burn patients. There is a paucity of information about the prevalence and antimicrobial resistance patterns of P. aeruginosa among burn patients in Ethiopia. Hence, this study was designed to assess the prevalence and antimicrobial-resistant patterns of P. aeruginosa among burn patients attending Yekatit 12 Hospital Medical College in Addis Ababa, Ethiopia.

METHODS

Hospital-based cross-sectional study was conducted at Yekatit 12 Hospital Medical College among burn patients from November 2020 to April 2021. Identification of P. aeruginosa was performed using Culture, Biochemical tests, and, Gram staining. Antimicrobial resistance testing was done using the Kirby-Bauer disc diffusion method. Logistic regression was computed to determine associated factors.

RESULTS

From 210 burn wound cultures, 27 (12.86%) were found positive for P. aeruginosa. All the isolates showed greater than 70% susceptibility to the tested antibiotics except Gentamycin, Ceftazidime, and, Ciprofloxacin. In addition, 33.33% of P. aeruginosa isolates were multidrug-resistant. Admission type, Hospital stay time and Total body surface area (TBSA) had a statistically significant association (all with P-value <0.05) with the acquisition of P. aeruginosa infection.

CONCLUSION

Overall, the prevalence of P. aeruginosa isolates among burn patients is almost 13%. Most P. aeruginosa isolates were sensitive to Imipenem, while they were most resistant to Gentamycin. One-third of P. aeruginosa were multidrug-resistant. This suggests the need to monitor the treatment of infection with the pathogen to limit the possibility of the emergence of multidrug-resistant isolates in burn centers.

Vasculature-on-a-chip technologies as platforms for advanced studies of bacterial infections

Bacterial infections frequently occur within or near the vascular network as the vascular network connects organ systems and is essential in delivering and removing blood, essential nutrients, and waste products to and from organs. In turn, the vasculature plays a key role in the host immune response to bacterial infections. Technological advancements in microfluidic device design and development have yielded increasingly sophisticated and physiologically relevant models of the vasculature including vasculature-on-a-chip and organ-on-a-chip models. This review aims to highlight advancements in microfluidic device development that have enabled studies of the vascular response to bacteria and bacterial-derived molecules at or near the vascular interface. In the first section of this review, we discuss the use of parallel plate flow chambers and flow cells in studies of bacterial adhesion to the vasculature. We then highlight microfluidic models of the vasculature that have been utilized to study bacteria and bacterial-derived molecules at or near the vascular interface. Next, we review organ-on-a-chip models inclusive of the vasculature and pathogenic bacteria or bacterial-derived molecules that stimulate an inflammatory response within the model system. Finally, we provide recommendations for future research in advancing the understanding of host-bacteria interactions and responses during infections as well as in developing innovative antimicrobials for preventing and treating bacterial infections that capitalize on technological advancements in microfluidic device design and development.

Extensive primary cutaneous fusariosis in a patient with burns: A case report and review of the literature

BACKGROUND

Fusarium species can cause a broad spectrum of human infections, ranging from superficial and locally invasive to disseminated, depending on the immune status of the host and portal of entry. Although several cases of cutaneous fusariosis in burn victims have been reported, molecular identification for pathogen recognition has been used only in a few cases.

CASE DESCRIPTION

In this report, we describe an uncommon case of extensive primary cutaneous fusariosis caused by Fusarium keratoplasticum in a patient who sustained injuries during stubble burning.

FINDINGS

A review of cases of cutaneous fusariosis in burn victims revealed that this uncommon infection could be lethal, and treatment strategies should focus on both surgical debridement and the initiation of systemic antifungal therapy. Furthermore, because skin defects can serve as a portal of entry for Fusarium species in burn victims, early and aggressive treatment is crucial to prevent serious consequences.

Multifunctional On-Demand Removability Hydrogel Dressing Based on in Situ Formed AgNPs, Silk Microfibers and Hydrazide Hyaluronic Acid for Burn Wound Healing

Elevated temperatures can deactivate tissues in the burn wound area, allowing pathogenic bacteria to multiply on the wound surface, ultimately leading to local or systemic infection. An ideal burn dressing should provide antibacterial properties and facilitate painless dressing changes. Silk microfibers coated with poly (2, 3, 4-trihydroxybenzaldehyde) (referred to as mSF@PTHB) to in situ reduce AgNO3 to silver nanoparticles (AgNPs) in a hydrazide hyaluronic acid-based hydrogel are utilized. The findings indicate a more homogeneous distribution of the silver elements compared to directly doped AgNPs, which also conferred antioxidant and antibacterial properties to the hydrogel. Moreover, hydrogels containing pH-responsive dynamic acylhydrazone bonds can undergo a gel-sol transition in a weak acid environment, leading to the painless removal of adhesive hydrogel dressings. Notably, the on-demand replaceable self-healing antioxidant hydrogel dressing exhibits antibacterial effects and cytocompatibility in vitro, and the wound-healing performance of the hydrogel is validated by treating a burn mouse model with full-thickness skin defects. It is demonstrated that hydrogel dressings offer a viable therapeutic approach to prevent infection and facilitate the healing of burn wounds.

Associated predictors of prolonged length of stay in patients surviving extensive burns: A large multicenter retrospective study

BACKGROUND

Patients with extensive burns are critically ill and have long treatment periods. Length of stay (LOS) is a good measure for assessing treatment. This study sought to identify predictors of prolonged LOS in patients with extensive burns (≥50% TBSA).

METHODS

This retrospective multicenter cohort study included adults aged ≥ 18 years who survived extensive burns in three burn centers in Eastern China between January 2016 and June 2022. Epidemiological, demographic and clinical outcomes data were extracted from electronic medical records and compared between patients with/without prolonged LOS, which was defined as LOS greater than the median. Logistic regression analysis was used to identify predictors of prolonged LOS.

RESULTS

The study sample included 321 patients, of whom 156 (48.6%) had an LOS of 58 days (IQR 41.0-77.0). Univariate regression analysis showed that increased total burn area and increased full-thickness burn area; electrical, chemical and other burns; increased erythrocytes, leukocytes, platelets or serum creatinine within 24 h of admission; concomitant inhalation injury, pulmonary edema, sepsis, bloodstream infection, wound infection, pulmonary infection, urinary tract infection, or HB < 70 g/L during hospitalization were associated with prolonged LOS in patients with extensive burns. Increased number of surgical operations, mechanical ventilation and renal replacement therapy were also associated with prolonged LOS (P < 0.05 or P < 0.001). Multivariate regression analysis revealed that increased total burn area (ratio 1.032, 95%CI 1.01-1.055; P = 0.004), electrical and chemical or other burns (3.282, 1.335-8.073; P = 0.01), development of wound infection (2.653 1.285-5.481; P = 0.008) and increased number of operative procedures (1.714, 1.388-2.116, P < 0.001) were significant predictors.

CONCLUSIONS

Increased area of full-thickness burn,occurrence of electrical and chemical or other burns,occurrence of wound infection and increased number of surgeries are the best predictors of prolonged LOS in patients with extensive burns. Clarifying relevant predictors of burn patients' LOS provides a reliable reference for clinical treatment.

Central venous catheter tip colonization and associated bloodstream infection in patients with severe burns under routine catheter changing

BACKGROUND

Although routine changing of central venous catheters (CVCs) is commonly performed in patients with severe burns, information on pathogen colonization of the CVC tip and associated bloodstream infections (BSIs) is limited in those patients.

METHODS

The medical records of 214 patients with severe burns who underwent routine CVC changing at 7-day intervals and their results of 686 pairs of CVC tips and concurrent blood cultures were retrospectively reviewed to evaluate the CVC colonization rate and associated BSI pathogens.

RESULTS

Of the 686 CVCs, 137 (20.0%) were colonized by pathogens, and 81 (59.1%) of them had BSIs caused by the same pathogen. Nonflame burn (P = .002), total body surface area burn ≥30% (P = .004), femoral catheterization (P = .001), CVC changing during pre-existing BSI (P < .001), and renal replacement therapy (P = .017) were associated with catheter-related BSI in the multivariate analysis. Most BSIs were caused by Gram-negative bacteria (most commonly Acinetobacter baumannii, Klebsiella pneumoniae, and Pseudomonas aeruginosa).

CONCLUSIONS

The CVC colonization rate in patients with severe burns and routine CVC changing was not high. Lengthening the CVC duration might be attempted in patients at a lower risk of catheter-related BSI although further prospective studies are necessary.

Effect of albumin substitution on pharmacokinetics of piperacillin/tazobactam in patients with severe burn injury admitted to the ICU

BACKGROUND

Pathophysiological changes in severely burned patients alter the pharmacokinetics (PK) of anti-infective agents, potentially leading to subtherapeutic concentrations at the target site. Albumin supplementation, to support fluid resuscitation, may affect pharmacokinetic properties by binding drugs. This study aimed to investigate the PK of piperacillin/tazobactam in burn patients admitted to the ICU before and after albumin substitution as total and unbound concentrations in plasma.

PATIENTS AND METHODS

Patients admitted to the ICU and scheduled for 4.5 g piperacillin/tazobactam administration and 200 mL of 20% albumin substitution as part of clinical routine were included. Patients underwent IV microdialysis, and simultaneous arterial plasma sampling, at baseline and multiple timepoints after drug administration. PK analysis of total and unbound drug concentrations under steady-state conditions was performed before and after albumin supplementation.

RESULTS

A total of seven patients with second- to third-degree burns involving 20%-60% of the total body surface were enrolled. Mean (SD) AUC0-8 (h·mg/L) of total piperacillin/tazobactam before and after albumin substitution were 402.1 (242)/53.2 (27) and 521.8 (363)/59.7 (32), respectively. Unbound mean AUC0-8 before and after albumin supplementation were 398.9 (204)/54.5 (25) and 456.4 (439)/64.5 (82), respectively.

CONCLUSIONS

Albumin supplementation had little impact on the PK of piperacillin/tazobactam. After albumin supplementation, there was a numerical increase in mean AUC0-8 of total and unbound piperacillin/tazobactam, whereas similar Cmax values were observed. Future studies may investigate the effect of albumin supplementation on drugs with a higher plasma protein binding.

Polymyxin B-targeted liposomal photosensitizer cures MDR A. baumannii burn infections and accelerates wound healing via M1/M2 macrophage polarization

Multidrug-resistant (MDR) Acinetobacter baumannii infections pose a significant challenge in burn wound management, necessitating the development of innovative therapeutic strategies. In this work, we introduced a novel polymyxin B (PMB)-targeted liposomal photosensitizer, HMME@Lipo-PMB, for precise and potent antimicrobial photodynamic therapy (aPDT) against burn infections induced by MDR A. baumanni. HMME@Lipo-PMB-mediated aPDT exhibited enhanced antibacterial efficacy by specifically targeting and disrupting bacterial cell membranes, and generating increased intracellular ROS. Remarkably, even at low concentrations, this targeted approach significantly reduced bacterial viability in vitro and completely eradicated burn infections induced by MDR A. baumannii in vivo. Additionally, HMME@Lipo-PMB-mediated aPDT facilitated burn infection wound healing by modulating M1/M2 macrophage polarization. It also effectively promoted acute inflammation in the early stage, while attenuated chronic inflammation in the later stage of wound healing. This dynamic modulation promoted the formation of granulation tissue, angiogenesis, and collagen regeneration. These findings demonstrate the tremendous potential of HMME@Lipo-PMB-mediated aPDT as a promising alternative for the treatment of burn infections caused by MDR A. baumannii.

Consensus on the treatment of second-degree burn wounds (2024 edition)

Second-degree burns are the most common type of burn in clinical practice and hard to manage. Their treatment requires not only a consideration of the different outcomes that may arise from the dressing changes or surgical therapies themselves but also an evaluation of factors such as the burn site, patient age and burn area. Meanwhile, special attention should be given to the fact that there is no unified standard or specification for the diagnosis, classification, surgical procedure, and infection diagnosis and grading of second-degree burn wounds. This not only poses great challenges to the formulation of clinical treatment plans but also significantly affects the consistency of clinical studies. Moreover, currently, there are relatively few guidelines or expert consensus for the management of second-degree burn wounds, and no comprehensive and systematic guidelines or specifications for the treatment of second-degree burns have been formed. Therefore, we developed the Consensus on the Treatment of Second-Degree Burn Wounds (2024 edition), based on evidence-based medicine and expert opinion. This consensus provides specific recommendations on prehospital first aid, nonsurgical treatment, surgical treatment and infection treatment for second-degree burns. The current consensus generated a total of 58 recommendations, aiming to form a standardized clinical treatment plan.

Analgesic Efficacy of Oxycodone in Postoperative Dressings after Surgical Treatment of Burn Wounds: A Randomised Controlled Trial

INTRODUCTION

This study aimed to assess the analgesic efficacy of oxycodone at doses of 10 mg and 20 mg in dressings after surgery of burn wounds.

MATERIAL AND METHODS

Twenty adult patients who underwent surgical treatment of third-degree burn wounds under general anaesthesia were included. Burn wounds were treated with dressings, to which oxycodone was added at 20 mg in Group 1 and 10 mg in Group 2. After the surgery, plasma oxycodone and noroxycodone concentrations were assayed, and pain intensity was assessed with Numerical Rating Scale (NRS).

RESULTS

In Group 1, no patient reported pain; in Group 2, four patients reported pain. The pain intensity, according to NRS, was 1-8. Plasma concentration of oxycodone in the blood serum was in the range of 1.24-3.15 ng/mL and 1.09-1.28 ng/mL in Group 1 and Group 2, respectively. Noroxycodone was not detected in the plasma. Adverse effects were not observed in any of the treated patients.

CONCLUSIONS

Oxycodone in dressings provides patients with adequate and safe analgesia.

Genomic landscape of NDM-1 producing multidrug-resistant Providencia stuartii causing burn wound infections in Bangladesh

The increasing antimicrobial resistance in Providencia stuartii (P. stuartii) worldwide, particularly concerning for immunocompromised and burn patients, has raised concern in Bangladesh, where the significance of this infectious opportunistic pathogen had been previously overlooked, prompting a need for investigation. The two strains of P. stuartii (P. stuartii SHNIBPS63 and P. stuartii SHNIBPS71) isolated from wound swab of two critically injured burn patients were found to be multidrug-resistant and P. stuartii SHNIBPS63 showed resistance to all the 22 antibiotics tested as well as revealed the co-existence of blaVEB-6 (Class A), blaNDM-1 (Class B), blaOXA-10 (Class D) beta lactamase genes. Complete resistance to carbapenems through the production of NDM-1, is indicative of an alarming situation as carbapenems are considered to be the last line antibiotic to combat this pathogen. Both isolates displayed strong biofilm-forming abilities and exhibited resistance to copper, zinc, and iron, in addition to carrying multiple genes associated with metal resistance and the formation of biofilms. The study also encompassed a pangenome analysis utilizing a dataset of eighty-six publicly available P. stuartii genomes (n = 86), revealing evidence of an open or expanding pangenome for P. stuartii. Also, an extensive genome-wide analysis of all the P. stuartii genomes revealed a concerning global prevalence of diverse antimicrobial resistance genes, with a particular alarm raised over the abundance of carbapenem resistance gene blaNDM-1. Additionally, this study highlighted the notable genetic diversity within P. stuartii, significant informations about phylogenomic relationships and ancestry, as well as potential for cross-species transmission, raising important implications for public health and microbial adaptation across different environments.

Management of Severe Burn Wounds Colonized With Multi-resistant Pseudomonas aeruginosa and Fusarium Using Marine Omega3 Wound Matrix in a Female Victim of War

War-related burns are common injuries, also among the civilian population. Additional trauma such as fractures or shrapnel wounds may add significant morbidity. Burn injuries in war zones are furthermore frequently undertreated and hence prone to complications. We report a case of a young female victim of war, whose severely infected burn wounds could be successfully healed using a combination of targeted antimicrobial therapy, wound conditioning using decellularized fish skin, and subsequent skin grafting.

The Antimicrobial Efficacy of Topically Applied Mafenide Acetate, Citric Acid and Wound Irrigation Solutions Lavanox and Prontosan against Pseudomonas aeruginosa

Since burn wound infections caused by Pseudomonas aeruginosa (PA) lead to major complications and sepsis, this study evaluates the antimicrobial efficacy of the wound irrigation solutions Prontosan (PRT), Lavanox (LAV), citric acid (CA) and mafenide acetate (MA) using microbiology assays and an ex vivo skin wound model. In suspension assays, all the solutions showed significant reductions in bacterial number (log10 reduction: CA 5.77; LAV 4.91; PRT 4.74; MA 1.23). The biofilm assay revealed that PRT and LAV reduced biofilm formation by ~25% after a 15 min treatment, while PRT was most effective after a 24 h treatment (~68%). The number of PA in biofilms measured directly after a 15 min treatment was reduced most effectively with CA and LAV (log10 reductions ~2.5), whereas after a 24 h treatment, all solutions achieved only 1.36-1.65 log10 reductions. In the skin wound model, PRT and LAV provided the highest bacterial reduction after a 15 min treatment (log10 reduction 1.8-1.9), while MA was more effective after a 22 h treatment (log10 reduction 3.6). The results demonstrated the antimicrobial efficacy of all solutions against PA. Further investigation is needed to explore the potential clinical applications of a combination or alternating use of these solutions for infection prophylaxis and treatment of wound infections caused by PA.

Concise Review on Scientific Approaches to Burns and Scars

Burns are large open surgical lesions bathed in virulent pus that result in rupturing of the cutaneous membrane, which has serious consequences such as an extensive loss of proteins, and body fluids, increased chances of infections, and sometimes death. These can be classified based on their penetration levels, i.e., first-degree burns penetrating the epidermis, second-degree burns including both epidermis and dermis, third-degree burns to both layers including the hair follicular cells, sweat glands and various core tissues, fourth-degree burns to adipose tissue, fifth stage burns to muscles, and sixth stage burns to bones. Wound healing/wound repair is a very perplexing process in which the tissues of the affected/burnt area repairs themselves to attain their original form and functionality but develop a scar at the wound site. This article mainly focuses on the algorithms to differentiate various degrees of burns, general first aid approaches to burns and scars, the rationale of treatment of burns, basic mechanisms highlighting the healing processes in humans in terms of free from scar formation as well as with scar formation at their elementary levels including cellular as well as biochemical levels, utility, and progression of pre-clinical data to humans and finally approaches for the improvement of scar formation in man.

Application of Aleppo pine extract for skin burn treatment

OBJECTIVE

To investigate the Pinus halepensis extracts and determine its healing and antibacterial effects, and to evaluate the treatment of skin burns.

METHODS

Aqueous and ethanolic extracts and topical based on Aleppo pine plant extracts were prepared. Thirty male and female Wistar rats were used to study the cutaneous toxicity of extracts from the bark of P. halepensis. The extracts' healing potential for burn wounds were also assessed by evaluating the clinical and macroscopic aspects of the wounds. The antibacterial activity of crude extracts of P. halepensis as well as its wound healing abilities was verified in this investigation.

RESULTS

In animals with acute dermal toxicity, there were no signs of treatment-related toxicity or death. The extracts of these plants could be transformed into phytomedicines for the treatment of infected wounds. The results demonstrated that formulated ointments are successful in treating second-degree burns in rats and may be suitable for the short-term therapeutic treatment of second-degree burns.

CONCLUSION

This study successfully answered our problem, regarding the efficacy of our extract for treating second-degree burns in rats. Further studies are needed to confirm these results by identifying the molecules responsible for these activities and examining their mechanism of action.

Molecular Machinery of the Triad Holin, Endolysin, and Spanin: Key Players Orchestrating Bacteriophage-Induced Cell Lysis and their Therapeutic Applications

Phage therapy, a promising alternative to combat multidrug-resistant bacterial infections, harnesses the lytic cycle of bacteriophages to target and eliminate bacteria. Key players in this process are the phage lysis proteins, including holin, endolysin, and spanin, which work synergistically to disrupt the bacterial cell wall and induce lysis. Understanding the structure and function of these proteins is crucial for the development of effective therapies. Recombinant versions of these proteins have been engineered to enhance their stability and efficacy. Recent progress in the field has led to the approval of bacteriophage-based therapeutics as drugs, paving the way for their clinical use. These proteins can be combined in phage cocktails or combined with antibiotics to enhance their activity against bacterial biofilms, a common cause of treatment failure. Animal studies and clinical trials are being conducted to evaluate the safety and efficacy of phage therapy in humans. Overall, phage therapy holds great potential as a valuable tool in the fight against multidrug- resistant bacteria, offering hope for the future of infectious disease treatment.

Antimicrobial Activity of Chitosan Scaffold Loaded with Soluble Factors of Different Probiotic Strains Against Multidrug Resistant Pseudomonas aeruginosa

Background

Bacterial infection remains the most frequent complication of burn injury, which can lead to sepsis, even if antibiotics are used topically and systemically. Pseudomonas aeruginosa (P. aeruginosa) is the main causative agent in many cases. The emergence of antibiotic-resistant strains in recent years has increased the need to find novel alternative therapies, such as probiotics. Therefore, this study aimed to examine the antimicrobial properties of probiotic cell-free supernatant (CFS), along with the potential use of a chitosan scaffold both as an antimicrobial agent and as a carrier for the delivery of these complexes.

Objective

Evaluation of the antimicrobial properties of cell-free soluble factors of probiotic bacteria both alone and in combination with chitosan scaffolds.

Materials and Methods

Nine isolates of P. aeruginosa previously identified by standard diagnostic tests were investigated. The antimicrobial effects of probiotics in the form of Pedilact® oral drop which contained three probiotic strains, Kidilact® sachet, which contained seven probiotic strains, and strains of Lactobacillus casei (L. casei) and Lactobacillus acidophilus (L. acidophilus) isolated from yogurt were studied by an agar well diffusion assay and by using CFS harvested at various growth stages, without pH neutralization. Chitosan with different concentrations of glutaraldehyde (GA) as a crosslinking agent was fabricated to produce a suitable scaffold for loading cell-free supernatants of probiotic strains. The scaffolds were then characterized using scanning electron microscopy. The antimicrobial properties of the CFS, chitosan, and chitosan scaffolds loaded with CFS were analyzed against MDR P. aeruginosa.

Results

In the agar well diffusion assay, CFS obtained from probiotic strains effectively inhibited the growth of a clinical strain of P. aeruginosa. This effect was observed when CFS was assessed without pH neutralization. Kidilact® was the most promising synbiotic formulation based on its inhibitory activity. The chitosan scaffold was successfully fabricated, as shown by SEM, and its structure was not affected by acidic CFS. The fabricated scaffolds were able to deliver CFS and, interestingly, antibacterial activity against P. aeruginosa when CFS was loaded on the chitosan scaffold was enhanced significantly.

Conclusion

The results of this study showed chitosan scaffold loaded with cell-free probiotics metabolites can be considered to be a promising antimicrobial dressing in wound healing applications.

Trends and Innovation in Negative Pressure Wound Therapy: A Review of Burn Wound Management

Significance: Burns result in irretrievable cell damage, which can occur upon exposure to hot surfaces, liquids, gases, ultraviolet or ionizing radiation, and through friction. Standard of care in burn management involves protecting the patient, limiting burn progression, and achieving wound closure. Negative pressure wound therapy (NPWT) and NPWT with instillation and dwell time (NPWTi-d) are two wound management options that have been shown to improve outcomes for burn patients in recent years. This work provides a general review of NPWT and NPWTi-d use in burn wound management. A literature search was performed using PubMed and Embase for peer-reviewed publications and conference abstracts written in English and reporting on burn management using NPWT and/or NPWTi-d from a single manufacturer between 2000 and 2021. All burn types were included. Recent Advances: Thirteen studies and 308 patients were available for assessment. Use of NPWT was reported in a majority of studies (n = 11). When conventional NPWT was applied, graft take of >90% was observed and consistent final wound closure was achieved. Two studies described NPWTi-d use for burn wound management. NPWTi-d use promoted granulation tissue development in burn wounds. Critical Issues: Limited high-level prospective evidence exists for use of NPWT and NPWTi-d in burn wound management. Future Directions: Available literature on the use of NPWT and/or NPWTi-d in burn care has reported improved outcomes in wound bed preparation, which can ultimately lead to final wound closure. The use of these modalities should be considered in management of burn care patients.

Pseudomonas aeruginosa kills Staphylococcus aureus in a polyphosphate-dependent manner

Due to their frequent coexistence in many polymicrobial infections, including in patients with burn or chronic wounds or cystic fibrosis, recent studies have started to investigate the mechanistic details of the interaction between the opportunistic pathogens Pseudomonas aeruginosa and Staphylococcus aureus. P. aeruginosa rapidly outcompetes S. aureus under in vitro co-cultivation conditions, which is mediated by several of P. aeruginosa's virulence factors. Here, we report that polyphosphate (polyP), an efficient stress defense system and virulence factor in P. aeruginosa, plays a role for the pathogen's ability to inhibit and kill S. aureus in a contact-independent manner. We show that P. aeruginosa cells characterized by low polyP level are less detrimental to S. aureus growth and survival while the gram-positive pathogen is significantly more compromised by the presence of P. aeruginosa cells that produce high level of polyP. We show that the polyP-dependent phenotype could be a direct effect by the biopolymer, as polyP is present in the spent media and causes significant damage to the S. aureus cell envelope. However, more likely is that polyP's effects are indirect through the regulation of one of P. aeruginosa's virulence factors, pyocyanin. We show that pyocyanin production in P. aeruginosa occurs polyP-dependent and harms S. aureus through membrane damage and the generation of reactive oxygen species, resulting in increased expression of antioxidant enzymes. In summary, our study adds a new component to the list of biomolecules that the gram-negative pathogen P. aeruginosa generates to compete with S. aureus for resources.

Human Wound and Its Burden: Updated 2022 Compendium of Estimates

Significance: Chronic wounds affect 10.5 million (up 2.3 million from the 2014 update) of U.S. Medicare beneficiaries. Chronic wounds impact the quality of life of nearly 2.5% of the total population of the United States. This fraction is larger in the elderly. These wounds can lead to a range of complications and health care costs. Given the aging population, the continued threat of diabetes and obesity worldwide, and the persistent problem of infection, it is expected that chronic wounds will continue to be a substantial clinical, social, and economic challenge. Disparities in the prevalence and management of chronic wounds exist, with underserved communities and marginalized populations often facing greater challenges in accessing quality wound care. These disparities exacerbate the public health burden. Recent Advances: U.S. Centers for Medicare and Medicaid Services had proposed revision of its local coverage determination limiting the use of skin substitute grafts/cellular and/or tissue-based products for the treatment of diabetic foot ulcers and venous leg ulcers in the U.S. Medicare population. In response to the comment phase, this proposal has been put on hold. The U.S. Food and Drug Administration (FDA) has renewed its focus on addressing nonhealing chronic wounds and has outlined efforts to address identified barriers to product development for nonhealing chronic wounds. The new approach places emphasis on engaging key wound healing stakeholders, including academia, professional associations, patient groups, reimbursement organizations, and industry. Finally, recent advances demonstrating that wounds closed by current FDA definition of wound closure may remain functionally open because of deficiencies in restoration of barrier function warrant revisiting the wound closure endpoint. Such "closed" wounds that are functionally open, also known as invisible wounds, are likely to be associated with high wound recurrence. Future Directions: Addressing the public health problem of chronic wounds will require a multifaceted approach that includes prevention, improved wound care management, and addressing the underlying risk factors.

Early wound excision within three days decreases risks of wound infection and death in burned patients

INTRODUCTION

In lieu of limited studies on the timing of burn wound eschar excision for burns, a more comprehensive analysis is indicated to determine the effects of early wound excision following burns. This study aims to address the outcomes of early wound excision in burn patients.

METHODS

Data collection were from TriNetX research database. Three groups of burn patients were stratified by the number of days in which they received burn wound excision within 14 days of injury. Five outcomes were observed: death, wound infection, sepsis, myocardial contractile dysfunction, and blood transfusion. Risk and incidence of various health outcomes were compared between the groups after propensity-matching age, sex, ethnicity, race and burn size using a z-test with p < 0.05 considered significant.

RESULTS

We identified 6158 burn patients with wound excision within 14 days of injury, the majority of whom (60.1%) received burn wound excision between 0 and 3 days after burn. 72.5% of patients had burns covering less than 20% of total body surface area. After propensity matching, we found a significantly lower risk of mortality in those who received burn wound excision within the first three days (3.84%) as compared to 8-14 days after burn (6.09%) (p < 0.05). Moreover, we found a decreased risk of wound infection in patients with burn wound excision within 0-3 days (37.84%) compared to those 4-7 days (42.48%) (p < 0.05). No statistical difference was detected in propensity-matched groups for myocardial contractile dysfunction, blood transfusion, or sepsis. In addition, the risk of hypertrophic scaring significantly decreased when wound excision was performed within 0-3 days (22% within 0-3 days, 28% within 4-7 days, p < 0.05).

CONCLUSION

Burn wound excision within 3 days of injury is beneficial when comparing to later treatment between 4 and 14 days, which results in a significantly lowered risk of mortality and infection in burn patient.