Oral allergy syndrome successfully treated with pollen immunotherapy

Some patients with allergic rhinitis have oral allergic reactions to fresh fruits and vegetables. This phenomenon has been termed "oral allergy syndrome" and is proposed to be due to cross-reacting allergens in the foods and pollens.

We report a patient with allergic rhinitis and oral allergy syndrome treated with pollen immunotherapy. Prior to immunotherapy, eating any fresh fruit or vegetable caused immediate itching and swelling of his tongue and throat. Prick skin test titration with pollens and foods was performed before and after 13 months of immunotherapy. Specific IgE immunoassay was performed with the same extracts on serum obtained before and after 7 and 13 months of immunotherapy. IgE immunoblots were performed on the same extracts separated by polyacrylamide gel electrophoresis using sera from the same time periods.

After 1 year on immunotherapy, the patient's allergic rhinitis symptoms resolved, and he was able to eat fresh fruits and vegetables without reaction. Skin testing and specific IgE immunoassay demonstrated a marked reduction in sensitivity to not only the pollens but the foods as well. Immunoblots revealed that the intensity of IgE binding to most components of the extracts, some common to pollens and foods, declined during immunotherapy.

These results support the notion that oral allergy syndrome is due to cross-reacting allergens in foods and pollens and may be amenable to treatment with pollen immunotherapy.