Incidence of Pollen-associated Food Allergies in Patients with Atopic Dermatitis

Abstract

RATIONALE: The aim of our study was to analyze both the frequency and the clinical relevance of pollen-associated food allergies in patients hospitalized in 2007 due to severe atopic dermatitis (AD).METHODS: 536 patients (330 f, 206 m; mean 29 yrs) with AD haven been investigated by specific IgE, prick-to-prick tests (native food), prick tests (pollen), and oral provocation tests. As “positive” patients were diagnosed when specific IgE and positive skin test and a positive clinical reaction (or a clear positive personal history) were observed.RESULTS: 60.1% demonstrated a clinical relevant allergy caused by pollen-associated foodstuff. In 35% the diagnosis was newly established. 51.5% reacted to more than one allergen: hazelnut (42%), raw apple (29,5%) almonds (25.0%), walnut (23.7%) and carrots (14.4%). The strongest prick test reaction was observed for grass and rye pollen. Mean IgE level of all patients was 3,459 U/l (7-47,690 U/l). Specific IgE against pollen was clustered (Immuno CAP low: levels 1-3; high: 4-6): high sensitization was observed against grass (41.4%), rye (40.7%), mugwort (28.9%) and birch (27.4%), respectively. Sensitization against egg, peanut, soy, fish, wheat, and cow's milk was negligible.CONCLUSIONS: One explanation for the rather high rate of patients with a clinically relevant food allergy could be a selection due to severity of their skin disease. It is of great interest whether this subgroup would have a clinical benefit using SIT against pollen regarding both the severity of the skin disease and induction of tolerance against food allergens, respectively. RATIONALE: The aim of our study was to analyze both the frequency and the clinical relevance of pollen-associated food allergies in patients hospitalized in 2007 due to severe atopic dermatitis (AD). METHODS: 536 patients (330 f, 206 m; mean 29 yrs) with AD haven been investigated by specific IgE, prick-to-prick tests (native food), prick tests (pollen), and oral provocation tests. As “positive” patients were diagnosed when specific IgE and positive skin test and a positive clinical reaction (or a clear positive personal history) were observed. RESULTS: 60.1% demonstrated a clinical relevant allergy caused by pollen-associated foodstuff. In 35% the diagnosis was newly established. 51.5% reacted to more than one allergen: hazelnut (42%), raw apple (29,5%) almonds (25.0%), walnut (23.7%) and carrots (14.4%). The strongest prick test reaction was observed for grass and rye pollen. Mean IgE level of all patients was 3,459 U/l (7-47,690 U/l). Specific IgE against pollen was clustered (Immuno CAP low: levels 1-3; high: 4-6): high sensitization was observed against grass (41.4%), rye (40.7%), mugwort (28.9%) and birch (27.4%), respectively. Sensitization against egg, peanut, soy, fish, wheat, and cow's milk was negligible. CONCLUSIONS: One explanation for the rather high rate of patients with a clinically relevant food allergy could be a selection due to severity of their skin disease. It is of great interest whether this subgroup would have a clinical benefit using SIT against pollen regarding both the severity of the skin disease and induction of tolerance against food allergens, respectively.