Norwegian Birch Rust Allergy Study

Used to collect data about symptoms potentially characterising the allergy of MB. A shortened version of the MeDALL questionnaire (mechanisms of the development of allergic diseases) will be used to collect data about allergic diseases and symptoms. POEM questionnaire (Patient-Oriented Eczema Measure) will be used to evaluate atopic eczema once in the season of MB and once outside MB and pollen seasons. The participant will also register symptoms during two periods, preferably 6 weeks during MB season autumn (August-September) 2022 and 2 weeks outside MB and pollen seasons in January/February 2023. During the 8 weeks of symptom registration the participants will receive an e-mail every other day with questions regarding symptoms and medication.

To clarify and verify the symptoms registered by the participants we will perform measurements of Peak Nasal Inspiratory Flow (PNIF) and spirometry. PNIF and spirometry will be used to assess airway obstruction through the nose and lungs, and will be performed in and outside the seasons of MB and pollen. Spirometry will be performed pre and post inhalation of bronchodilating medicine (reversibility test). Some of the participants (patients and controls) will be randomised to nasal provocation test (NPT), performed outside the seasons of MB and pollen, and for those PNIF and spirometry will be carried out before and after NPT.

To evaluate the symptoms as specific for allergy the participants will be tested with skin prick test (SPT) with MB and common airway allergens, serum specific IgE (sIgE) to MB and common airway allergens, nasal provocation test (NPT) with MB and passive basophil activation test (pBAT) with MB. Blood samples for the sIgE and pBAT will be performed in MD season, while SPT and NPT will be performed outside seasons of MB and pollen. We will compare the results from SPT, sIgE and pBAT with the results from NPT to calculate sensitivity and specificity of SPT, sIgE and pBAT. All those tests demand that we are able to develop MB extracts that are suitable for those tests.