Spatial transcriptomics reveals altered lipid metabolism and inflammation-related gene expression of sebaceous glands in psoriasis and atopic dermatitis.

Sebaceous glands drive acne, however, their role in other inflammatory skin diseases remains unclear. To shed light on their potential contribution to disease development, we investigated the spatial transcriptome of sebaceous glands in psoriasis and atopic dermatitis patients across lesional and non-lesional human skin samples. Both atopic dermatitis and psoriasis sebaceous glands expressed genes encoding key proteins for lipid metabolism and transport such as ALOX15B, APOC1, FABP7, FADS1/2, FASN, PPARG, and RARRES1. Also, inflammation-related SAA1 was identified as a common spatially variable gene. In atopic dermatitis, genes mainly related to lipid metabolism (e.g. ACAD8, FADS6, or EBP) as well as disease-specific genes, i.e., Th2 inflammation-related lipid-regulating HSD3B1 were differentially expressed. On the contrary, in psoriasis, more inflammation-related spatially variable genes (e.g. SERPINF1, FKBP5, IFIT1/3, DDX58) were identified. Other psoriasis-specific enriched pathways included lipid metabolism (e.g. ACOT4, S1PR3), keratinization (e.g. LCE5A, KRT5/7/16), neutrophil degranulation, and antimicrobial peptides (e.g. LTF, DEFB4A, S100A7-9). In conclusion, our results show that sebaceous glands contribute to skin homeostasis with a cell type-specific lipid metabolism, which is influenced by the inflammatory microenvironment. These findings further support that sebaceous glands are not bystanders in inflammatory skin diseases, but can actively and differentially modulate inflammation in a disease-specific manner.

Outlier detection in dermatology: Performance of different convolutional neural networks for binary classification of inflammatory skin diseases.

BACKGROUND: Artificial intelligence (AI) and convolutional neural networks (CNNs) represent rising trends in modern medicine. However, comprehensive data on the performance of AI practices in clinical dermatologic images are non-existent. Furthermore, the role of professional data selection for training remains unknown. OBJECTIVES: The aims of this study were to develop AI applications for outlier detection of dermatological pathologies, to evaluate CNN architectures' performance on dermatological images and to investigate the role of professional pre-processing of the training data, serving as one of the first anchor points regarding data selection criteria in dermatological AI-based binary classification tasks of non-melanoma pathologies. METHODS: Six state-of-the-art CNN architectures were evaluated for their accuracy, sensitivity and specificity for five dermatological diseases and using five data subsets, including data selected by two dermatologists, one with 5 and the other with 11 years of clinical experience. RESULTS: Overall, 150 CNNs were evaluated on up to 4051 clinical images. The best accuracy was reached for onychomycosis (accuracy = 1.000), followed by bullous pemphigoid (accuracy = 0.951) and lupus erythematosus (accuracy = 0.912). The CNNs InceptionV3, Xception and ResNet50 achieved the best accuracy in 9, 8 and 6 out of 25 data sets, respectively (36.0%, 32.0% and 24.0%). On average, the data set provided by the senior physician and the data set provided in accordance with both dermatologists performed the best (accuracy = 0.910). CONCLUSIONS: This AI approach for the detection of outliers in dermatological diagnoses represents one of the first studies to evaluate the performance of different CNNs for binary decisions in clinical non-dermatoscopic images of a variety of dermatological diseases other than melanoma. The selection of images by an experienced dermatologist during pre-processing had substantial benefits for the performance of the CNNs. These comparative results might guide future AI approaches to dermatology diagnostics, and the evaluated CNNs might be applicable for the future training of dermatology residents.

Increasing incidence of Trichophyton tonsurans in Munich-A single-centre observation.

BACKGROUND: Tinea capitis and tinea corporis are highly prevalent fungal skin infections, which globally are mainly caused by Microsporum canis and Trichophyton rubrum, respectively. While in the United States and Great Britain Trichophyton tonsurans is widely prevalent as a causative pathogen, it so far only plays a minor role in Germany. OBJECTIVES: Since the frequency of pathogenic species varies regionally and temporally, this study assesses the proportion of Trichophyton tonsurans infections in the dermatology department of a large university hospital in Germany from 2019 to 2022 and thoroughly characterises the affected patient population. PATIENTS/METHODS: This retrospective study at the Technical University of Munich analyses mycological culture results regarding the identified dermatophyte and infection site. Detailed patient and disease-related information on Trichophyton tonsurans positive patients was obtained. RESULTS: In 2022, 23 patients of 111 dermatophyte culture-positive patients tested positive for Trichophyton tonsurans. This accounted for 20.7% and represented a tenfold increase from 2.1% in 2019. Contact sports were only practiced by 21.7% of patients, and no common hotspot or other linkage could be identified between the cases. Additionally, 47.8% of the patients received a systemic treatment, with 30.4% visiting the clinic more than three times. In 2022, 21.7% were diagnosed with a simultaneous infection of the capillitium and body, whereas this was only observed in 7.1% of cases in 2019 to 2021. CONCLUSIONS: This study suggests an increase of Trichophyton tonsurans infections via several routes of transmission.

Keratinocytes Regulate the Threshold of Inflammation by Inhibiting T Cell Effector Functions.

Whilst the importance of keratinocytes as a first-line defense has been widely investigated, little is known about their interactions with non-resident immune cells. In this study, the impact of human keratinocytes on T cell effector functions was analyzed in an antigen-specific in vitro model of allergic contact dermatitis (ACD) to nickel sulfate. Keratinocytes partially inhibited T cell proliferation and cytokine production. This effect was dependent on the keratinocyte/T cell ratio and was partially reversible by increasing the number of autologous dendritic cells. The inhibition of T cell proliferation by keratinocytes was independent of the T cell subtype and antigen presentation by different professional antigen-presenting cells. Autologous and heterologous keratinocytes showed comparable effects, while the fixation of keratinocytes with paraformaldehyde abrogated the immunosuppressive effect. The separation of keratinocytes and T cells by a transwell chamber, as well as a cell-free keratinocyte supernatant, inhibited T cell effector functions to the same amount as directly co-cultured keratinocytes, thus proving that soluble factor/s account for the observed suppressive effects. In conclusion, keratinocytes critically control the threshold of inflammatory processes in the skin by inhibiting T cell proliferation and cytokine production.

Trotz einer großen Auswahl wirksame Medikamente: Psoriatiker scheinen immer noch untertherapiert zu sein.

HINTERGRUND UND ZIELE: Durch die Entwicklung neuer anti-psoriatischer Medikamente und verbesserte Strukturen zu deren flächendeckender Einführung hat sich die medizinische Versorgung von Psoriasis-Patienten deutlich verbessert. In dieser Studie haben wir die tatsächliche Inanspruchnahme des Gesundheitswesens untersucht und Gründe für die Unzufriedenheit der Betroffenen ermittelt. PATIENTEN UND METHODIK: Diese nicht-interventionelle Querschnittsstudie wurde als anonyme Online-Befragung von 12/2018 bis 01/2019 in Deutschland durchgeführt. Teilnehmer mit einer selbstberichteten, von einem Arzt gestellten Psoriasis-Diagnose und Symptomen beantworteten Fragen zu ihrer Erkrankung, deren Einfluss auf das tägliche Leben und ihrer medizinischen Versorgung. ERGEBNISSE: 649 Teilnehmer mit einem mittleren Alter von 42,5 ± 13,7 Jahren und ausgewogener Geschlechterverteilung (männlich: 50,2 %) wurden ausgewertet. 54,1 % waren zum Zeitpunkt der Studie in ärztlicher Behandlung, 45,9 % nicht. Von den Teilnehmern mit medizinischer Versorgung waren 59,3 % nur mäßig oder weniger zufrieden mit ihrer Behandlung. Gründe für die Unzufriedenheit mit der Medikation waren unter anderem mangelnde Wirksamkeit und Nebenwirkungen. Von den nicht in ärztlicher Behandlung befindlichen Teilnehmern wurde "Zeitmangel des Arztes" als Hauptgrund für die Nichtinanspruchnahme ärztlicher Hilfe angegeben. SCHLUSSFOLGERUNGEN: Trotz der Verfügbarkeit effizienter Therapieoptionen in Deutschland sind viele Betroffene mit Psoriasis unzufrieden. Diese unterbehandelte Gruppe wurde als neue Zielgruppe identifiziert.

Despite large choice of effective therapies: Individuals with psoriasis still seem undertreated.

BACKGROUND AND OBJECTIVES: Due to the development of new anti-psoriatic drugs in combination with improved structures for implementation throughout Germany, the medical care of psoriasis patients has markedly improved. In this study we investigated the real-life utilization of the health care system and identified reasons for dissatisfaction in affected individuals. PATIENTS AND METHODS: This non-interventional cross-sectional study was conducted as an anonymous online survey from 12/2018 to 01/2019 in Germany. Participants with a self-reported physician-confirmed diagnosis of psoriasis and symptoms answered questions about their disease, its influence on daily life and their medical care. RESULTS: 649 participants with a mean age of 42.5 ± 13.7 years and equal gender distribution (male: 50.2 %) were evaluated. 54.1 % received medical treatment at the time of the study, 45.9 % did not. Among the participants with medical care, 59.3 % were only moderately or less satisfied with their treatment. Reasons for dissatisfaction with the medication included lack of efficacy and side effects. Participants without medical treatment specified a physician's lack of time as a main reason for not seeking medical help. CONCLUSIONS: Despite the availability of efficient therapeutic options in Germany, many individuals with psoriasis are not satisfied. This under-treated group was identified as a new target population.

Interest in Sexually Transmitted Infections: Analysis of Web Search Data Terms in Eleven Large German Cities from 2015 to 2019.

Incidence of sexually transmitted infections (STIs) such as chlamydia, gonorrhea, and syphilis has increased in recent years in the US and in European countries. In order to implement effective educational programs, the interests of target populations have to be identified. Since the internet is an important source of information-gathering on health issues, this study investigates web search data in large German cities related to STIs. Google Ads Keyword Planner was used to identify STI-related terms and their search volume in eleven German cities from June 2015 to May 2019. The data obtained were analyzed descriptively with regard to total search volumes, search volumes of specific thematic areas, and search volumes per 100,000 inhabitants. Overall, 741 terms with a total search volume of 5,142,560 queries were identified, with more than 70% of all search queries including a specific disease and "chlamydia" being the overall most often searched term (n = 1,196,160). Time courses of search behavior displayed a continuous interest in STIs with synchronal and national rather than regional peaks. Volumes of search queries lacked periodic patterns. Based on the findings of this study, a more open public discussion about STIs with linkage to increased media coverage and clarification of responsibilities among all STI-treating disciplines concerning management of STIs seem advisable.