OBJECTIVE CLINICAL AND LABORATORY STUDIES OF IMMEDIATE HYPERSENSITIVITY REACTIONS TO FOODS IN ASTHMATIC-CHILDREN

[摘要] Clinical and laboratory observations were made with 38 children afflicted with chronic severe asthma (reversible obstructive airway disease) in which hypersensitivity to food was incriminated in the histories. Symptoms were evoked in double-blind food challenges in only 11/38 children and 14/70 challenges. The symptoms were characteristic of immediate-type hypersensitivity and were chiefly gastrointestinal, even though asthma was the common presenting complaint. There were no delayed reactions. Peanut was responsible for 8 reactions, [hen] egg for 5 and cow''s milk for 1. The result which could best be used for diagnosis was a significant wheal reaction in a skin test done by the puncture technique using a verified extract of 1:20 wt/vol concentration. No subject with clinically significant, symptomatic hypersensitivity to food had a negative puncture test, and puncture tests were positive in only 10/56 instances of negative reactions in food challenges. Laboratory observations included release of histamine and enzymes from leukocytes and the levels of neutrophil enzymes in serum before and after food provocation tests. While these determinations were of interest with respect to the immunochemical basis of reactions to foods, they were not useful for practical clinical diagnosis. The outstanding laboratory finding was the spontaneous release of 25%-100% of the histamine from leukocytes in all patients proved clinically hypersensitive by food challenges. This suggests that this parameter may be an indicator of immediate-type hypersensitivity to food. A general approach to food hypersensitivity was developed in which the immunologic components coupled with quantitative concentration-response relationships render comprehensible the distinction between asymptomatic (immunologic) hypersensitivity and symptomatic (clinical) hypersensitivity.