Occupational allergic rhinoconjunctivitis and asthma due to fennel seed.

Background: A patient with complaints of rhinitis and asthma occurring at work presented for consultation.

Objectives: To evaluate the role of the foods and spices with which he worked, in the causation of his complaints, and to evaluate his immune reactivity to these materials.

Methods: Allergy skin testing and in vitro RAST assays were carried out. After demonstrating specific reactivity to fennel, SDS-PAGE electrophoreses was carried out.

Results: Positive skin tests to grass, ragweed, and freshly prepared fennel seed were found. Serum IgE antibodies to fennel were quite high. Immunoblotting studies showed reactions to two components in fennel extract as well as to components in mugwort, paprika, short ragweed and black pepper.

Conclusion: This case of occupational rhinitis and asthma in an atopic individual involves sensitivity to unique allergens in fennel, with molecular weights of 67 to 75 KD.