Food allergy preceded by contact urticaria due to the same food: Involvement of epicutaneous sensitization in food allergy

There have recently been reports suggesting that sensitization to food allergens may occur outside the intestinal tract, especially through the skin. To clarify the role of epicutaneous sensitization in food allergy, we investigated the clinical characteristics of adult patients with food allergies preceded by contact urticaria due to the same foods. We investigated clinical characteristics of 15 patients (20–51 years of age; 5 men and 10 women), who had food allergies preceded by contact urticaria. Fourteen patients were contact urticaria due to the causative foods during occupationally cooking, whereas 1 patient during face pack. In the occupational group, causative foods included rice, wheat, fruits, vegetables, fish, shrimp and cuttlefish; in the fresh cucumber paste case the cause was cucumber. In the 15 patients, the causative foods were fresh, not processed, and were tolerated by most (9/15, 60%) after heating. Regarding to symptoms after ingestion of the causative foods, the most frequently induced symptoms was oral symptoms (14/15, 93.3%), followed by urticaria (4/15, 26.7%), abdominal symptoms (3/15, 20%). The duration between the start of jobs or face pack, and the onset of contact urticaria was from 1 month to 19 years (mean, 8.7 years). The duration between the onset of contact urticaria and the onset of food allergy was from a few weeks to 6 years (mean, 11 months). One sushi cook experienced severe anaphylactic shock after ingestion of fish. In the occupational group, 13 of 15 patients (86.7%) had atopic dermatitis or hand eczema, indicating that the impaired skin barrier might be a risk for food allergies induced by epicutaneous sensitization. Epicutaneous sensitization of foods could induce food allergy under occupational cooking and skin-care treatment with foods in adults.