Abstract
BACKGROUND: Asthma is a chronic respiratory disease comprising different pheno- and endotypes. Diagnostic tools for the identification of allergic versus non-allergic asthma are needed for new precision medicine-based treatments. OBJECTIVE: To determine IgE sensitization profiles to multiple micro-arrayed allergen molecules in adult patients with asthma in the Austrian LEAD (Lung, hEart, sociAl, boDy) cohort; to compare IgE- and non-IgE sensitized patients with asthma; and to define possible allergen-specific immunotherapy concepts for sensitized patients. METHODS: Out of 893 patients with a history of asthma, patients with current asthma (n = 436) were analyzed for IgE sensitizations to 110 micro-arrayed molecules from airborne and food allergen sources and by skin prick testing (SPT) with 10 allergen extracts (English plantain, mugwort, ragweed, timothy grass, ash tree, mites, dog, cat, Alternaria alternata, and Fagales mix). Clinical asthma-related parameters were compared between patients with IgE sensitization to asthma allergen molecules and non-IgE sensitized patients with asthma. RESULTS: IgE sensitization was detected in 73.2% of patients with asthma using 63 micro-arrayed respiratory allergens. The most recognized respiratory outdoor allergen molecules were Bet v 1 (32.8%) and Ole e 1 (23.2%) followed by grass pollen, ragweed, and mugwort allergens. Fel d 1 was the most frequently recognized respiratory indoor allergen molecule (42.7%) followed by house dust mite and dog allergen molecules. Micro-arrayed allergens allowed the identification of IgE reactivity profiles indicative of genuine sensitizations to different allergen sources. IgE-sensitized patients were significantly younger than non-IgE-sensitized patients with asthma (median age 44 versus 58 years). Patients sensitized to respiratory allergens showed significantly better lung function (FEV1, FVC and FEV/FVC) and less dyspnea but more allergic bronchitis than non-IgE-sensitized patients with asthma. More IgE-sensitized patients used antihistamines but fewer inhaled corticosteroids than non-IgE-sensitized patients with asthma. Interestingly, eosinophil counts were lower both in ICS-treated as well as untreated sensitized patients than in non-sensitized patients with asthma. CONCLUSION: Molecular allergy diagnosis allowed the detection of genuine IgE sensitizations in adult patients with asthma; enabling stratification for precision medicine-based forms of personalized treatments such as allergen-based immunotherapy (AIT) and/or administration of biological treatments in asthma.