Background: Drug reaction with eosinophilia and systemic symptoms (DRESS) is a severe multi-organ drug hypersensitivity reaction (DHR) involving T cells. DRESS patients have a heightened risk (~25%) of developing multiple drug hypersensitivity (MDH) to unrelated drugs from the first reaction. This project aims to characterise DRESS, focusing on those with and without MDH, to identify potential biomarkers for further drug reactions. Methods: This multicentre cross-sectional study analysed clinical features and immune responses, including T cell activation and in vitro cytokine secretion using Cyto-LTT. The study included 20 DRESS patients (12 with MDH), 8 maculopapular exanthema (MPE) patients (4 with MDH), and a control group of 9 healthy donors (HD). Clinical assessments included detailed histories, skin testing, and the RegiSCAR score for diagnosing DRESS. Results: The Cyto-LTT improved diagnostic sensitivity, particularly in DRESS patients, identifying 19% of drugs that were negative by skin testing. MDH patients’ leukocytes exhibited stronger and broader secretions of cytokines and cytotoxic mediators, up to ten-fold higher compared to DHR patients with a single drug sensitisation. T cells from recovered delayed DHR patients exhibited signs of chronic activation after resolution, with elevated CD69 and PD-1 but reduced CD38 and OX-40 levels compared to HD. Conclusion: Recovered delayed DHR patients display an altered T cell activation profile suggesting a “chronic disease” state, possibly explaining the heightened risk of MDH. Increased cytokine secretions, such as stimulation index > 10, especially for cytotoxic mediators, may differentiate those at risk for MDH.

Goals: The intranasal Schirmer test (INS) is a quick method to objectify nasal secretion. This study aims to use the INS to assess nasal secretion change through direct nasal allergen provocation (NPT). Material and Methods: This prospective single-center study included patients who received allergy diagnostics using NPT and anterior rhinomanometry (aRMM). The Schirmer filter paper was attached to the nasal septum bilaterally pre- and post-allergen provocation. Additionally, all participants completed the sinonasal outcome test 22 (SNOT-22). The difference in wetting length before and after allergen provocation was investigated. Moreover, a cut-off value for allergic rhinitis were calculated. Results: A total of n = 25 patients and n = 25 in the control group were included. Patients with a positive result in NPT showed a significantly higher secretion in the provoked nasal cavity (mean difference = 13.95 mm; p = 0.01). The increased moisture level through provocation resulted in an area under the curve (AUC) of 0.814. A cut-off value of 2.75 mm wetting length increase (Youden index = 0.532) was calculated (sensitivity = 81.8% and specificity = 71.4%). Allergy diagnostic patients scored significantly higher in the SNOT-22 than the control group (25.04 score difference; p < 0.001). Conclusion: The INS represents a straightforward and cost-effective test to assess intranasal secretion changes in allergy diagnostics. The incorporation of the INS in the NPT protocol could particularly enhance treatment efficacy for patients with inconclusive NPT results or it could serve as a substitute for other objective measurements like aRMM or acoustic rhinometry.

Aim: The 4th Davos Declaration, convened during the Global Allergy Forum (GAF) in Davos, aimed to elevate patient care for patients with atopic dermatitis (AD) by uniting experts and stakeholders. The forum addressed the high prevalence of AD, with a strategic focus on advancing research, treatment, and management to meet the evolving challenges in the field. Methods: This multidisciplinary forum brought together top leaders from research, clinical practice, policy, and patient advocacy to discuss the critical aspects of AD, including neuroimmunology, environmental factors, comorbidities, and breakthroughs in prevention, diagnosis, and treatment. The discussions were geared towards fostering a collaborative approach to integrate these advancements into practical, patient-centric care. Results The forum underlined the mounting burden of AD, attributing it to significant environmental and lifestyle changes. It acknowledged the progress in understanding AD and in developing targeted therapies but recognized a gap in translating these innovations into clinical practice. Emphasis was placed on the need for enhanced awareness, education, and stakeholder engagement to address this gap effectively and to consider environmental and lifestyle factors in a comprehensive disease management strategy. Conclusion: The 4th Davos Declaration marks a significant milestone in the journey to improve care for people with AD. By promoting a holistic approach that combines research, education, and clinical application, the Forum sets a roadmap for stakeholders to work together to improve patient outcomes in AD, reflecting a commitment to adapt and respond to the dynamic challenges of AD in a changing world.

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