AIRWAY REACTIVITY CHANGES IN ASTHMATIC-PATIENTS UNDERGOING BLINDED FOOD CHALLENGES

To investigate the possible pathogenic role of food allergy in asthma, airway hyperresponsiveness was measured by methacholine inhalation ch allenges (MIC) performed before and after double-blind, placebo-contro lled food challenges (DBPCFC) in 26 food-allergic, asthmatic patients. Airway hyperresponsiveness was classified as severe in two cases (PD( 20)FEV(1) < 2 breath units, BU), moderate in 18 (PD(20)FEV(1):2-20 BU) , and mild in six (PD(20)FEV(1) > 20 BU). Medications included albuter ol (81%), inhaled steroids (38%), cromolyn (35%), and theophylline (23 %). MICs were performed in the afternoon after DBPCFC. Of the 22 posit ive DBPCFC, 12 involved chest symptoms (cough, wheezing, or both). Ano ther 10 positive DBPCFCs included laryngeal, gastrointestinal, and/or skin symptoms without any chest symptoms. Significant increases in air way hyperresponsiveness were evident in seven of 12 patients experienc ing chest symptoms during DBPCFC. Significant increases in airway hype rresponsiveness were observed in one patient without chest symptoms du ring a positive DBPCFC and one patient after a negative DBPCFC. Howeve r, this last patient had a negative MIC with the same antigen 1 yr lat er. These studies indicate that food-induced allergic reactions can in crease airway reactivity, and may do so without inducing acute asthma.