Search

IntroductionLesional skin of atopic dermatitis (AD) is often colonised byStaphylococcus aureusand the bacterial abundance increases during a flare. However, the role ofS. aureusand the skin microbiome in the pathogenesis of AD, including its influence on the dysfunctional skin barrier and immune response, remains to be elucidated. In this study, the temporal relationship between alterations in the skin barrier function, inflammation and microbiome is examined in adults with AD.Methods and analysisThis clinical study consists of 81 adult patients with AD, as defined by the Hanifin and Rajka criteria, and 41 age and sex-matched controls. The objectives are to examine alterations in the skin microbiome, skin barrier and immune response during (1) an untreated AD flare, (2) an AD flare treated with topical corticosteroids (TCS), (3) an AD flare treated with systemic dicloxacillin/placebo and TCS or (4) cutaneous exposure to either autologousS. aureus, staphylococcal enterotoxin B or a vehicle. Skin biopsies, tape strips, skin and nasal swabs are collected and analysed using RNA sequencing, multiplex immunoassays, liquid chromatography-mass spectrometry and 16S rDNA. Blood samples are analysed for filaggrin gene mutations and leucocyte gene expression.Ethics and disseminationThe scientific Ethical Committee of the Capital Region in Denmark (phases I and II: H-20011047, phases III and IV: H-21079287), the local data protection agency (phases I and II: P-2020-165, phases III and IV: P-2022-250) and the Danish Medicines Agency (phases III and IV: EudraCT 2021-006883-25, ClinicalTrials.gov:NCT05578482) have approved the studies. Participants will give written informed consent prior to study initiation. The study is conducted in accordance with the Helsinki Declaration. Outcomes will be presented at national and international conferences and in international peer-reviewed publications.Trial registration numberNCT05578482, EudraCT 2021-006883-2.

IntroductionAtopic dermatitis (AD) is a highly prevalent, chronic, inflammatory skin disease. Several orally administered Janus kinase inhibitors (JAKis, including baricitinib, upadacitinib and abrocitinib) have received a marketing authorisation for AD.Clinical trials in rheumatoid arthritis (RA) have flagged up a potential risk of JAKi-induced venous thromboembolic events (VTEs). Accordingly, the summary of product characteristics for a JAKi must mention VTEs as potential adverse drug reactions. In contrast to RA, AD per se is not associated with an elevated risk of VTEs. Assessing this potential risk among patients with AD would shed further light on the putative underlying relationship between JAKis and VTEs.Our research question is to investigate whether JAKi administration increases the risk of VTEs in adults with AD. Our primary objective is to assess the risk of VTEs in adults with AD exposed to JAKis compared to AD adults not exposed to JAKis, and our secondary objective is to evaluate whether JAKi initiation acts as a trigger of VTEs in adults with AD within 3 months.Methods and analysisHence, we have designed (1) a nested case–control study and (2) a case–time control study in a cohort of adults with AD with data from the French national health insurance system (2017–2025).Here, we describe the study protocol, our methodological choices and certain novel aspects, including the combined value of the two assumptions and the use of an exhaustive national health insurance database with potentially greater statistical power for studying rare events in the population of patients with AD at a low risk of VTEs (thus limiting the influence of confounding factors).Ethics and disseminationThe protocol has been approved by an independent ethics committee and registered with the French National Data Protection Commission. The study’s findings will be published in peer-reviewed scientific journals and presented at international conferences.

BackgroundOveruse and misuse of antibiotics is a public health problem in low-income and middle-income countries. Although the association of antibiotics with atopic and allergic diseases has been established, most studies focused on prenatal exposure and the occurrence of disease in infants or young children.ObjectiveTo investigate the association of preschool use of antibiotics with atopic and allergic skin diseases in young adulthood.DesignPopulation-based retrospective cohort.Setting and participantsThe first-year college students (n=20 123) from five universities were investigated. The sampled universities are located in Changsha, Wuhan, Xiamen, Urumqi and Hohhot, respectively.MethodsWe conducted a dermatological field examination and a questionnaire survey inquiring the participants about the frequency of upper respiratory tract infection (URTI) and the preschool antibiotics use (prior to 7 years old). The two-level probit model was used to estimate the associations, and adjusted risk ratio (aRR) and 95% CI were presented as the effect size.ResultsA total of 20 123 participants with complete information was included in the final analysis. The frequent antibiotics use intravenously (aRR 1.36, 95% CI 1.14 to 1.62) and orally (aRR 1.18, 95% CI 1.01 to 1.38) prior to 7 years old was significantly associated with atopic dermatitis in young adulthood. Similar trends could be observed in allergic skin diseases among those who use antibiotics orally and intravenously, with RRs of 1.16 (95% CI 1.01 to 1.34) and 1.33 (95% CI 1.13 to 1.57), respectively.ConclusionsPreschool URTI and antibiotics use significantly increases the risk of atopic and allergic skin diseases in young adulthood.

ObjectivesLearning to take control of one’s health is an important part of the transition from adolescence to adulthood. This study aimed to explore young adults’ perceptions of living with atopic dermatitis (AD) in relation to the concept of self-management.DesignA qualitative study with an inductive approach was performed through semistructured interviews (n=15). The interviews were recorded, transcribed verbatim and analysed with systematic text condensation.ParticipantsYoung adults (mean age 23,4 years) with persistent AD in a longitudinal population-based birth cohort. To capture experience of living with persistent AD (preschool/school-age onset) of different severity (mild to severe/very severe), a purposive selection was performed. In total, 15 young adults were included. Persistent AD (preschool/school-age onset) was defined as dry skin in combination with itchy rash of typical localisation in the 12 months preceding the 16-year and the 24-year follow-ups. Severity was self-assessed using the Patient Oriented Eczema Measure.ResultsDespite having experience of AD since childhood, the respondents expressed uncertainty about treatment and how it affected their bodies. Their uncertainties and feelings affected how they used topical corticosteroids. The respondents emphasised that they perceived availability of healthcare and knowledge about treatment of AD among healthcare providers to be limited. The participants did not state any experiences of support to self-management from healthcare, which affect young adults’ possibilities to take full control of their AD care.ConclusionsYoung adults with preschool/school-age onset of AD are unsure how to treat and manage the disease. One explanation may be insufficient transition process.