Studies of hypersensitivity reactions to foods in infants and children.

In order to extend previous investigations of adverse reactions to foods performed at this institution, 68 children, aged 5 mo to 15 yr, were studied. All subjects reported a history of adverse reaction to ingestion of one or more of the 14 foods under study. Sixteen of 43 subjects, 3 yr of age or older, had 22 adverse reactions during 94 food challenges with one or more of the 14 foods. All reactions confirmed were to peanut or other nuts, milk, egg, and soy. Skin testing with 1:20 weight/volume concentrations of food extracts applied by the puncture technique produced a net wheal reaction 3 mm or greater in all subjects 3 yr of age or older in whom double-blind food challenges confirmed the history of adverse reaction. Thirteen of 25 children less than 3 yr of age manifested adverse reactions during 49 food challenges. Skin testing by puncture technique produced a net wheal 3 mm or greater in 9 children less than 3 yr of age in whom food challenge elicited a clinical response within 2 hr. One of 4 subjects less than 3 yr of age in whom the adverse reaction occurred more than 4 hr after food challenge exhibited a wheal to puncture skin test of 3 mm or greater. These studies suggest that at present double-blind food challenge is an indispensible tool for the unequivocal evaluation of adverse reactions to foods.