Is Patch Testing with Food Additives Useful in Children with Atopic Eczema?

Background: Atopy patch testing is a useful way to determine delayed-type hypersensitivity reactions to foods and aeroallergens. Although food additives have been accused of worsening atopic eczema symptoms, according to recent studies the role of food additives in atopic eczema remains unclear. The purpose of our study was to investigate food additive hypersensitivity in a group of children with atopic eczema by using standardized atopy patch testing and to determine the role of food additive hypersensitivity in atopic eczema.

Methods: Thirty-four children with atopic eczema and 33 healthy children were enrolled in the study. Children who consumed foods containing additives and did not use either antihistamines or local or systemic corticosteroids for at least 7 days prior to admission were enrolled in the study. All children were subjected to atopy patch testing and after 48 and 72 hours their skin reactions were evaluated by using the guidelines.

Results: Positive atopy patch test results were significantly higher in the atopic eczema group. Forty-one percent of the atopic eczema group (n = 14) and 15.2% (n = 5) of the control group had positive atopy patch test results with food additives (p = 0.036) (estimated relative risk 1.68, case odds 0.7, control odds 0.17). Carmine hypersensitivity and the consumption of foods containing carmine, such as gumdrops, salami, and sausage, were significantly higher in the children with atopic eczema.

Conclusion: This is the first study investigating hypersensitivity to food additives in children with atopic eczema. Our results indicate that carmine may play a role in atopic eczema.