During cutaneous tick attachment, the feeding cavity becomes a site of transmission for tick salivary compounds and tick-borne pathogens. However, the immunological consequences of tick feeding for human skin remain unclear. Here, we assessed human skin and blood samples upon tick bite and developed a human skin explant model mimicking Ixodes ricinus bites and tick-borne pathogen infection. Following tick attachment, we observed rapidly occurring patterns of immunomodulation, including increases in neutrophils and cutaneous B and T cells. T cells upregulated tissue residency markers, while lymphocytic cytokine production was impaired. In early stages of Borrelia burgdorferi model infections, we detected strain-specific immune responses and close spatial relationships between macrophages and spirochetes. Preincubation of spirochetes with tick salivary gland extracts hampered accumulation of immune cells and increased spirochete loads. Collectively, we showed that tick feeding exerts profound changes on the skin immune network that interfere with the primary response against tick-borne pathogens.

The World Health Organization (WHO) declared certain fungal pathogens as global health threats for the next decade. Candida auris (C. auris) is a newly emerging skin-tropic multidrug-resistant fungal pathogen that can cause life-threatening infections of high mortality in hospitals and healthcare settings. Here, we address an unmet need and present novel native ex vivo skin models, thus extending previous C. auris-host interaction studies. We exploit histology and immunofluorescence analysis of ex vivo skin biopsies of human adult and fetal, as well as mouse origin infected with C. auris via distinct routes. We demonstrate that an intact skin barrier efficiently protects from C. auris penetration and invasion. Although C. auris readily grows on native human skin, it can reach deeper layers only upon physical disruption of the barrier by needling or through otherwise damaged skin. By contrast, a barrier disruption is not necessary for C. auris penetration of native mouse skin. Importantly, we show that C. auris undergoes morphogenetic changes upon skin penetration, as it acquires pseudohyphal growth phenotypes in deeper human and mouse dermal layers. Taken together, this new human and mouse skin model toolset yields new insights into C. auris colonization, adhesion, growth and invasion properties of native versus damaged human skin. The results form a crucial basis for future studies on skin immune defense to colonizing pathogens, and offer new options for testing the action and efficacy of topical antimicrobial compound formulations.

Depending on their extent, burn injuries require different treatment strategies. In cases of severe large-area trauma, the availability of vital skin for autografting is limited. Donor skin allografts are a well-established but rarely standardized option for temporary wound coverage. Ten patients were eligible for inclusion in this retrospective study. Overall, 202 donor skin grafts obtained from the in-house skin bank were applied in the Department of Plastic and Reconstructive and Aesthetic Surgery, Medical University of Vienna. Between 2017 and 2022, we analysed the results in patient treatment, the selection of skin donors, tissue procurement, tissue processing and storage of allografts, as well as the condition and morphology of the allografts before application. The average Abbreviated Burn Severity Index (ABSI) was 8.5 (range, 5–12), and the mean affected total body surface area (TBSA) was 46.1% (range, 20–80%). In total, allograft application was performed 14 times. In two cases, a total of eight allografts were removed due to local infection, accounting for 3.96% of skin grafts. Six patients survived the acute phase of treatment. Scanning electron microscope images and histology showed no signs of scaffold decomposition and intact tissue layers of the allografts. The skin banking program and the application of skin allografts at the Vienna Burn Center can be considered successful. In severe burn injuries, skin allografts provide time by serving as sufficient wound coverage after early necrosectomy. Having an in-house skin banking program at a dedicated burn centre is particularly advantageous since issues of availability and distribution can be minimized. Skin allografts provide a reliable treatment option in patients with extensive burn injuries.

Summary: Introduction: Currently, very little detailed information on the epidemiological distribution and specificities of severely burned patients during the coronavirus disease 2019 (COVID-19) pandemic is available. This retrospective study aims to describe and compare this specific patient population based on 114 patients who were treated between March 2019 and March 2021 at the Center for Severe Burn Injuries at the Medical University of Vienna. Methods: To answer the research questions, a retrospective cohort study has been conducted over a period of 24 months, starting in March 2019 and ending in March 2021. To evaluate the epidemiological differences, the patients were divided into 2 observation periods of 12 months each. Results: In the period from 12 March 2020 to 11 March 2021, a total of 62 patients were admitted to the Center for Severe Burn Injuries. In comparison, only 52 patients were admitted in the same period of the previous year, which corresponds to an increase of 19.2%. In addition, it was noted that during the 2019–2020 observation period, 27% of patients were female and 73% male, whereas during the pandemic the gender distribution was 42% female and only 58% male. During the pre-pandemic observational period, 13 out of 52 patients admitted died (25%), whereas during the pandemic, 17 out of 62 patients succumbed to their injuries (27%). Conclusion: Although the severity of the COVID-19 pandemic seems to be decreasing, especially due to the increasing availability of vaccines, there is a need for more data on the impact of the crisis on severely burned patients. In contrast to the current literature, we have seen a greater number of inpatient admissions to the Center for Severe Burn Injuries, as well as significant differences in gender distribution. Our data also suggest that the circumstances of the pandemic have no influence on the likelihood of survival for patients with severe burns.

Background/Objectives: It is often assumed that patients with pre-existing psychiatric conditions are more prone to severe burn injuries due to impaired judgment or risky behaviors. However, the relationship between psychiatric illnesses and the incidence and severity of burn injuries remains unclear. This study aims to examine the prevalence of psychiatric illnesses among severely burned patients and compare it to the general population. Methods: We analyzed the data of all patients admitted to our burn intensive care unit with severe burn injuries between 2014 and 2024. Data collection focused on the prevalence of psychiatric illnesses and substance abuse. The prevalence rates in our study cohort were compared to available data provided by the Federal Ministry of Social Affairs, Health, Care and Consumer Protection of Austria, representing the general population as well as data from long-term population studies. The severity and outcome of burn injuries were compared between patients with and without psychiatric conditions. Results: A total of 644 patients were included in this study. The analysis revealed that 176 (27.4%) patients had a documented psychiatric comorbidity, which is comparable to the prevalence of psychiatric conditions in the general population, estimated at 25–30%. However, the prevalence of alcohol abuse among burn patients was notably higher, with 64 patients (9.9%), compared to approximately 3% in the general population. Despite the higher prevalence of alcohol abuse, the severity and extent of burn injuries were similar between patients with and without pre-existing psychiatric conditions. Conclusions: Our findings challenge the common belief that pre-existing psychiatric conditions increase the risk or severity of severe burn injuries. While alcohol abuse is indeed more prevalent among burn patients, the overall distribution of psychiatric illnesses is similar to that in the general population. This suggests that psychiatric conditions may not directly influence the incidence or severity of burn injuries.