Published Online: June 13, 2014
Current treatments for eczema include topical corticosteroids and moisturizers. Many creams for dry skin and eczema are advertised as “natural” products, and some may contain potential food allergens such as goat’s milk, cow’s milk, coconut milk or oil, oats and nut oils. Application of these moisturizers (containing food allergens) to damaged skin could cause food allergen sensitization, leading to reactions when the food is subsequently eaten.
In an article recently published in The Journal of Allergy and Clinical Immunology: In Practice, Voskamp and colleagues report a case study of a woman who experienced severe anaphylaxis—requiring several doses of intramuscular adrenaline—immediately after eating a salad containing goat’s cheese, a food she had consumed without problem in the past. Questioning revealed that she had previously been applying a skin moisturizer containing goat’s milk, which she ceased after experiencing increasing skin redness and itch. Serum testing in the laboratory confirmed that she had high levels of allergy antibodies (IgE) to goat’s milk. Additionally, serum IgE binding tests identified IgE binding to the actual moisturizer, which could be completely blocked by goat’s milk, indicating that the IgE was binding to goat’s milk protein within the moisturizer. Furthermore, another test of her white blood cells in the laboratory, the basophil activation test (representing histamine release from cells involved in the allergic reaction), showed basophil activation by goat’s milk and also by the moisturizer.
Combined, the clinical history and laboratory data support the sensitization route as the eczematous skin application of the allergen in the moisturizer, with subsequent anaphylaxis when the allergen was eaten in food. This route of sensitization has been hypothesized for wheat, oat, peanut and goat’s milk allergy, due to sensitization from products such as soaps and oils used to alleviate eczema. This study provides the first confirmatory link of the immunological response of a patient to a food allergen in a skin product, with subsequent anaphylaxis. The authors remind clinicians and patients that skin care ought to be bland, avoiding agents capable of sensitization, especially food allergens.
The Journal of Allergy and Clinical Immunology: In Practice is an official journal of the AAAAI, focusing on practical information for the practicing clinician.