Linking cross-reactivity clusters of food and respiratory allergens in PAMD@ to asthma and duration of allergy.

BACKGROUND: Component resolved diagnosis, recently redefined as precision allergy medicine diagnosis - PAMD@, may help understanding allergic cross-reactivity patterns among polysensitized patients and their clinical implication. OBJECTIVE: We aimed to investigate similarities among allergens by empirically determining the occurrence of co-sensitization patterns and to relate them to clinical features, in particular to asthma. METHODS: A retrospective cohort study in 1057 participants suspected to have allergic sensitization was performed in Vienna. To define cross-reactivity patterns, cluster analysis for 671 patients who showed reaction to at least one of the allergens in ISAC112 was performed and followed by multivariate logistic regression analysis to relate clusters and clinical symptoms, in particular current asthma. RESULTS: We determined 18 cross-reactivity clusters, comprising of 6 food, 10 respiratory, and 2 other clusters of allergens. Overall, 14% of the cohort patients were positive for 1 cross-reactivity cluster and 23% to 2 or more clusters. Multisensitized patients who were sensitized to PR-10 allergen proteins in addition to Bermuda timothy grass pollen clusters showed the highest association with asthma (odds ratio, 4.22 and 95% CI: 2.32-7.68) and an increase of 10 years of the duration of allergy increased the odds for a combined sensitization to PR-10 cluster and Bermuda-timothy cluster by 1.27 (95% CI: 1.06-1.53). CONCLUSION: Similarities among IgE positivity patterns determined by ISAC112 revealed 18 cross-reactivity clusters. This PAMD@ approach allowed prediction of clinical features and revealed that certain cross-reactivity patterns are related to duration of allergic symptoms.

Elevated oxytocin and noradrenaline indicate higher stress levels in allergic rhinitis patients: Implications for the skin prick diagnosis in a pilot study.

BACKGROUND & AIMS: The effects of acute stress on allergic symptoms are little understood. The intention of this clinical study was to study the effects of acute stress and related mediators in allergic rhinitis (AR), taking the wheal and flare reaction in skin prick testing (SPT) as a readout. METHODS: 19 healthy and 21 AR patients were first subjected to SPTs with grass pollen-, birch pollen- and house dust mite allergen extracts, histamine and negative control. Subsequently, participants were exposed to a standardized Trier Social Stress Test (TSST), followed by SPT on the contralateral forearm. Stress responders were identified based on the salivary cortisol levels and State-subscale of State-Trait-Anxiety Inventory (STAI-S). Blood samples were collected before and after TSST and adrenaline, noradrenaline, serotonin, oxytocin, platelet activating factor and prostaglandin D2 were analyzed by enzyme immunoassay (EIA). RESULTS: SPT results of 14/21 allergics and 11/19 healthy who responded with stress after TSST were evaluated. No significant differences regarding SPT to allergens or histamine before and after the stress test could be calculated at the group level. But, the wheal and flare sizes after TSST increased or decreased substantially in several individuals, and unmasked sensitization in one "healthy" person, which could not be correlated with any mediator tested. The most significant finding, however, was that, independent of TSST, the baseline levels of oxytocin and noradrenaline were significantly higher in allergics. CONCLUSION: High baseline levels of noradrenaline points toward higher stress levels in allergic patients, which might be counterregulated by elevated oxytocin. Moreover, our data indicate that acute stress may have a significant influence on SPT fidelity in susceptible individuals.