Characteristics of pollen-related food allergy based on individual pollen allergy profiles in the Chinese population

Abstract

Background: Patients with pollinosis are often multi-sensitized to diverse pollen allergens. However, little is known about pollen allergy types among Chinese pollinosis patients. This study is aimed to characterize clinical manifestations of food allergy among patients with different types of pollen allergy.

Methods: We retrospectively analyzed 402 pollinosis patients from an outpatient allergy department of the Peking Union Medical College Hospital who had been diagnosed by experienced allergists. All included patients who answered a questionnaire regarding seasonal pollinosis and clinical symptoms after ingestion of food and underwent intradermal skin tests. Total IgE and specific IgE levels were quantified by ImmunoCAP, using 0.35 kUA/L as a threshold for positivity.

Results: The patients were divided into 3 groups, based on the season during which they experienced symptoms and the 2 peaks of Chinese airborne pollen: spring-tree pollen symptoms group (SG), autumn-weed pollen symptoms group (AG), and a combined spring and autumn pollen symptoms group (CG). Birch pollen (83%) and ash pollen (74%) were common allergens among patients with spring symptoms, while mugwort pollen (87%) was a common allergen among patients with autumn symptoms. In total, 30% of the study population experienced pollen-related food allergy. Pollen-related food allergies were more prevalent among the single-season symptom groups (68% and 50% for the SG and AG, respectively) than among the CG (20%). All patients with pollen-related food-induced anaphylaxis exhibited autumn weed pollen symptoms. Except for 2 patients, all patients with food-induced anaphylaxis were allergic to mugwort pollen. In the SG, all patients with food allergy were sensitive to birch pollen, with birch and Bet v 1-specific IgE levels higher in this group than in the group without food allergy (p < 0.001). In the AG, Art v 3 was more prevalent among patients with pollen-related food allergy than without food allergy (79% vs. 33%, p < 0.001), a proportion similar to the one in the CG (67% vs. 48%, p = 0.01). Meanwhile, the Art v 3-specific IgE levels among patients with pollen-related food allergy were higher than among tolerant patients in the AG (p < 0.001) and CG (p = 0.02). Unexpectedly, the Art v 3-specific IgE levels were higher in patients with food-induced anaphylaxis than with oral allergy syndrome only in the CG.

Conclusions: Bet v 1 (a Pathogenesis-related 10 protein) and Art v 3 (a non-specific lipid transfer protein; nsLTP) are candidate molecular biomarkers for the diagnosis of food allergies in patients with season-specific pollen-related allergies. Measuring pollen allergen component-specific IgE levels might be an effective tool for the management of pollinosis in clinical practice in China.

Keywords: Anaphylaxis; Art v 3; Bet v 1; Food allergy; Pollinosis.

Fig. 1

Frequencies of specific pollen allergies by seasonal symptoms group. A wheal size of at least 5 mm and detection of specific IgE >0.35 kUA/L were considered positive indicators of allergy. SG, spring symptoms group; AG, autumn symptoms group; CG, combined seasons group

Fig. 2

Specific IgE levels in participants with pollen-related food allergy, stratified by symptom season: A) spring symptom group, B) autumn symptom group, and C) combined seasons group. ∗, p < 0.05; ∗∗, p < 0.01; ∗∗∗, p < 0.001. sIgE, specific IgE; SG, spring symptom group; AG, autumn symptom group; CG, combined seasons group; PA, pollen allergy; PFA, pollen-related food allergy

Fig. 3

The results of the receiver operating curve analysis for pollen allergen components as predictors of pollen-related food allergy in different seasonal symptoms groups: SG, spring symptom group; AG, autumn symptom group; CG, combined seasons group

Fig. 4

Specific gE levels of mugwort and Art v 3 were compared among patients with oral allergy syndrome and food-induced anaphylaxis. The diagnostic power of predicting systemic reactions to pollen-related food in different groups. ∗∗, p < 0.01. sIgE, specific IgE; AG, autumn symptom group; CG, combined seasons group; OAS, oral allergy syndrome; FIA, food-induced anaphylaxis

Fig. 5

Results of the correlation analysis between pollen allergen components (Bet v 1 and Artv 3) and food allergen components (Pru p 1 and Pru p 3) in patients with and without food allergy. sIgE, specific IgE; SG, spring symptoms group; AG, autumn symptoms group; PA, pollen allergy; PFA, pollen-related food allergy