MILWAUKEE (AAAAI) -- Allergy to cooked potatoes is responsible for severe allergic disease in infants and young children, according to a study in the September 2002 Journal of Allergy and Clinical Immunology (JACI). The JACI is the peer-reviewed scientific journal of the American Academy of Allergy, Asthma and Immunology (AAAAI).

Food allergy is the main cause of allergic symptoms in infants and young children. There are a limited number of foods responsible for the majority of food-induced allergic reactions in children, namely cow's milk, eggs, peanut, soy, fish and wheat. However, the clinical effects of allergic reactions to potato and the effectiveness of elimination diets on such reactions have not been previously described.

To determine the severity of potato allergy, Liliane F.A. De Swert, MD, and colleagues from the University Hospital Gasthuisberg, Leuven, Belgium, evaluated eight infants and young toddlers with atopic dermatitis (eczema) suspected of having an allergy to cooked potatoes. Allergis sensitivity was assessed by skin prick tests with homemade cooked and uncooked potato extracts, a commercial extract, and by using IgE immunoblots from potato extract. Nine other children with eczema and milk allergy served as control subjects in this small study.

Skin prick test responses were positive for cooked potato extracts in 7 of 7 potato-sensitive children, and for the commercial extract in 8 of 8 of these patients. Only 1 of the 9 control patients had a positive skin test. During immunoblotting, 8 of 8 sensitive patients reacted to one or more protein bands compared with 0 of 9 from the control group. Oral challenges with cooked potato were positive in 7 of 7 sensitive patients. When cooked potatoes were eliminated from the diet of the potato-sensitive children, the severity of their atopic dermatitis improved significantly (utilizing an objective eczema severity scoring method) over a period of several months.

Researchers concluded that allergy to cooked potatoes might be responsible for severe allergic disease in a small number of young children with symptoms of immediate hypersensitivity, atopic dermatitis, or both. This allergy can be controlled by following a potato elimination diet.

This JACI study was the first to show, by evaluating the symptoms before and after elimination of potato from the diet, that hypersensitivity to cooked potatoes was responsible for severe symptoms of atopic disease in a very select group of young children.