Modern Aspects of Burn Injury Immunopathogenesis and Prognostic Immunobiochemical Markers (Mini-Review)

Red blood cell distribution width at admission and the short-term mortality of patients with severe burn injury: a meta-analysis

OBJECTIVE

Red blood cell distribution width (RDW) is a marker of inflammation and oxidative stress, and its elevation has been associated with poor outcomes in critically ill patients. This meta-analysis aimed to evaluate the association between RDW at admission and short-term mortality in patients with severe burn injury.

METHODS

We systematically searched PubMed, Embase, and Web of Science up to August 2024, following PRISMA 2020 and Cochrane guidelines. Cohort studies of adult severe burn patients who reported RDW at admission and short-term mortality were included. Meta-analyses were performed using random-effects models, with mean difference (MD) and relative risk (RR) calculated for RDW and mortality outcomes, respectively. Subgroup and sensitivity analyses were conducted to assess heterogeneity.

RESULTS

Nine cohort studies involving 5268 patients were included. Overall, RDW at admission was higher in nonsurvivors compared to survivors [MD: 0.95%, 95% confidence interval (CI): 0.52-1.38, p < 0.001, I2 = 57%]. In addition, a high RDW was associated with an increased risk of short-term mortality (RR: 1.76, 95% CI: 1.41-2.19, p < 0.001, I2 = 77%). Sensitivity analyses by excluding one dataset at a time confirmed the robustness of these findings. Subgroup analyses revealed no significant differences based on clinical settings, patient age, sex, follow-up duration, or study quality.

CONCLUSIONS

RDW at admission is a significant predictor of short-term mortality in patients with severe burn injury. This finding highlights the potential role of RDW as a simple and effective marker for risk stratification in these patients.

Phage Therapy in a Burn Patient Colonized with Extensively Drug-Resistant Pseudomonas aeruginosa Responsible for Relapsing Ventilator-Associated Pneumonia and Bacteriemia

Pseudomonas aeruginosa is one of the main causes of healthcare-associated infection in Europe that increases patient morbidity and mortality. Multi-resistant pathogens are a major public health issue in burn centers. Mortality increases when the initial antibiotic treatment is inappropriate, especially if the patient is infected with P. aeruginosa strains that are resistant to many antibiotics. Phage therapy is an emerging option to treat severe P. aeruginosa infections. It involves using natural viruses called bacteriophages, which have the ability to infect, replicate, and, theoretically, destroy the P. aeruginosa population in an infected patient. We report here the case of a severely burned patient who experienced relapsing ventilator-associated pneumonia associated with skin graft infection and bacteremia due to extensively drug-resistant P. aeruginosa. The patient was successfully treated with personalized nebulized and intravenous phage therapy in combination with immunostimulation (interferon-γ) and last-resort antimicrobial therapy (imipenem-relebactam).

An Overview of Recent Developments in the Management of Burn Injuries

According to the World Health Organization (WHO), around 11 million people suffer from burns every year, and 180,000 die from them. A burn is a condition in which heat, chemical substances, an electrical current or other factors cause tissue damage. Burns mainly affect the skin, but can also affect deeper tissues such as bones or muscles. When burned, the skin loses its main functions, such as protection from the external environment, pathogens, evaporation and heat loss. Depending on the stage of the burn, the patient's condition and the cause of the burn, we need to choose the most appropriate treatment. Personalization and multidisciplinary collaboration are key to the successful management of burn patients. In this comprehensive review, we have collected and discussed the available treatment options, focusing on recent advances in topical treatments, wound cleansing, dressings, skin grafting, nutrition, pain and scar tissue management.

Multiplexed Human Gene Expression Analysis Reveals a Central Role of the TLR/mTOR/PPARγ and NFkB Axes in Burn and Inhalation Injury-Induced Changes in Systemic Immunometabolism and Long-Term Patient Outcomes

Burn patients are subject to significant acute immune and metabolic dysfunction. Concomitant inhalation injury increases mortality by 20%. In order to identify specific immune and metabolic signaling pathways in burn (B), inhalation (I), and combined burn-inhalation (BI) injury, unbiased nanoString multiplex technology was used to investigate gene expression within peripheral blood mononuclear cells (PBMCs) from burn patients, with and without inhalation injury. PBMCs were collected from 36 injured patients and 12 healthy, non-burned controls within 72 h of injury. mRNA was isolated and hybridized with probes for 1342 genes related to general immunology and cellular metabolism. From these specific gene patterns, specific cellular perturbations and signaling pathways were inferred using robust bioinformatic tools. In both B and BI injuries, elements of mTOR, PPARγ, TLR, and NF-kB signaling pathways were significantly altered within PBMC after injury compared to PBMC from the healthy control group. Using linear regression modeling, (1) DEPTOR, LAMTOR5, PPARγ, and RPTOR significantly correlated with patient BMI; (2) RPTOR significantly correlated with patient length of stay, and (3) MRC1 significantly correlated with the eventual risk of patient mortality. Identification of mediators of this immunometabolic response that can act as biomarkers and/or therapeutic targets could ultimately aid the management of burn patients.