Food allergy in children.

The diagnosis of hypersensitivity reactions to foods in infancy and childhood requires the use of clinical skills and laboratory diagnostic methods to identify suspect foods. Patients and parents occasionally may need to keep food/symptom diaries to explore the association of foods and adverse reaction. Skin testing or RAST may shorten the list of potential allergens because of their excellent negative predictive value. Except for obvious serious allergic reactions after ingestion of a single food, confirmation of the reaction may be ideally confirmed by a DBPCFC, especially if the reported symptoms are subjective in nature. Equivocal responses should be repeated. Although many in vitro and in vivo diagnostic methods have been developed to potentially improve the diagnosis of food allergy in children, no test has been able to predict the results of the DBPCFC with any greater accuracy than skin tests or RAST. The "perfect" test with excellent positive and negative predictive values has yet to be developed.