Oral allergy syndrome

ABSTRACT

Oral allergy syndrome (OAS) is an IgE-mediated allergy caused by cross-reacting antigenic determinants in pollens and various fruits, vegetables, and nuts which are known as the most common food allergy in adults. Cross-reactive antigenic proteins include pathogenesis-related-10 protein, profilin, cross-reactive carbohydrate determinant and lipid transfer protein. The prevalence of OAS has been reported at up to 70% of birch pollen allergy. A nationwide multicenter study in our country has recently reported that the prevalence of OAS in Korea is 41.7% of pollen allergy. Typical symptoms of OAS are tingling, itching sense and edema of lips, mouth, and throat immediately after ingestion of raw fruits, vegetables, or nuts. These can progress to systemic symptoms including anaphylaxis. The diagnosis can be made by typical clinical history in patients with pollen allergy. Skin prick test using fresh fruits extracts can be helpful in confirming sensitization to foods, which has better sensitivity than commercial skin prick test or serum specific IgE test. Treatment of OAS is to avoid causative foods. Self-injectable epinephrine should be considered in the case of anaphylaxis. Allergen-specific immunotherapy to pollens has also been tried.