Evaluation of immediate adverse reactions to foods in adult patients: I. Correlation of demographic, laboratory, and prick skin test data with response to controlled oral food challenge

Abstract

Forty-five adult patients, referred to here as the index population, with a history of immediate adverse reactions after food ingestion were evaluated by history, physical examination, laboratory studies, and skin testing. Fifty-six percent of these patients reported adverse reactions to only one food, whereas 84% of the patients reported up to three foods as being capable of eliciting reactions. The average age obtained by history at which adverse reactions began to occur was 19 4 5 yr. The occurrence of these reactions persisted over an average of 14 4 5 yr. Most reactions involved the gastrointestinal tract alone or in combination with the skin or respiratory tract. The most frequently involved foods were shellfish, peanuts, eggs, fish, tomatoes, and walnuts. Twenty-five of the patients participated in oral challenge with the suspected food. The food challenge was positive in 10 patients. Comparison of information obtained by history including personal or family history of any other allergic disease, age of onset of sensitivity, the length of time of suspected sensitivity in years, and the number of foods to which the sensitivity was believed to exist revealed no significant differences between food challenge-positive (FC+) and food challenge-negative (FC−) patients. However, a significant difference in the reaction patterns reported by history in the FC+ and FC− patients was noted in that FC + patients more often described reactions in which a combination of gastrointestinal, respiratory, and dermatologic symptoms occurred. The complete blood count with differential, blood chemistries, and serum immunoglobulin levels were similar in both groups. Nine of 10 patients in the FC+ group had positive skin tests to the food that produced clinical symptoms. The skin tests were positive to a suspected food in three of the 15 patients in the FC− group. The results obtained suggest that an immediate adverse reaction to a food may have its initial presentation when the patient has reached adulthood, that such individuals tend to be atopic, that three or fewer foods are generally implicated, and that such sensitivities may persist for years. Patients who describe previous reactions involving combined gastrointestinal, respiratory, and dermatologic symptoms and have a positive skin test to the suspected food are more likely to experience a reaction on subsequent exposure to that food.