Oral allergy syndrome in birch pollen sensitized patients in Korea: Results of a Retrospective Chart Review

RATIONALE: Oral allergy syndrome (OAS) is a form of a contact allergic reaction that mainly occurs when the oropharynx comes in contact with foods. It is caused by cross-reacting allergens found in both pollens and food, and the most common type of OAS is the birch pollen-related (BPR) food allergy. Although OAS is a common form of food allergy in adults, there have been few epidemiologic studies in Korea.

METHODS: To evaluate the prevalence and triggers of BPR food allergy, a retrospective chart review was conducted on 1427 patients who underwent a skin prick test for inhalant allergens at the Asthma and Allergy Clinic in Seoul National University Bundang Hospital from JAN 2011 to DEC 2016.

RESULTS: Of the 125 birch pollen sensitive patients, only 3 patients were birch pollen mono-sensitive and the others showed multi-sensitivity to trees, grasses, weeds or house dust mite allergens. In total, 20% of the study population experienced food allergy and the OAS was the main clinical manifestation (96.15%). Apple, peach and persimmon were identified as frequent triggers. The incidence of OAS was higher in females and there was no significant difference between the groups with and without OAS in age, serum eosinophil counts or serum total IgE levels.

CONCLUSIONS: Although we discovered some difference in the prevalence with previous reports, OAS was still common to atopy patients who were sensitized to birch pollen. Larger epidemiologic studies are needed to figure out Asian specific Oral allergy syndrome.