Phadia’s T3 test is used to detect blood levels of the IgE (antibodies) responsible for allergic reactions to birch pollen and often alder pollen. People who are allergic to birch pollen often have allergic reactions to a number of foods including fresh fruit, nuts and peanuts. These cross allergies (pollen-food syndrome) are usually less severe, and symptoms are generally limited to the mouth and throat (oral allergy syndrome). The interpretation chart accompanying the result expresses the probability of an allergic reaction to birch and alder pollen, but not necessarily the severity of the reaction. Case history (symptoms, relation to the season and foods associated with oral allergy syndrome, etc.) and clinical examination by the physician are essential for a reliable interpretation of the results.
An anti-birch IgE result of less than 0.35 kilounits per litre (< 0.35 kU/L) indicates that birch (and alder) pollen are probably not responsible for the symptoms reported by the person, but it DOES NOT COMPLETELY RULE OUT THIS POSSIBILITY. Certain molecular allergy tests are available to specify whether a birch-food cross allergy actually stems from a primary allergy to birch pollen or from true allergies to birch and certain foods (peanuts, nuts, etc.).