Bronchial reactivity in schoolchildren allergic to food

Background Food allergy (FA) is associated with an increased risk of asthma. Objective To evaluate whether bronchial hyperreactivity (BHR) occurs in children with FA depending on the presence of respiratory symptoms. Methods Fifty-four children with FA and 62 without FA were studied for BHR, defined as a provocation concentration of methacholine that caused a decrease in forced expiratory volume in 1 second of 20% (PC 20 ). The diagnosis of FA was established using questionnaires, clinical criteria, skin prick tests, serum specific IgE antibodies, and a double-blind placebo-controlled food challenge. Results Among nonasthmatic children, BHR was diagnosed in 15 (47%) with FA and in 7 (17%) without FA ( P 20 in children with FA alone was 2.8 [1.38] mg/mL and was significantly higher than that in children with asthma alone (0.88 [1.01] mg/mL) or with asthma and FA (0.96 [0.83] mg/mL) ( P Conclusions Children with FA had increased BHR independent of respiratory symptoms. Although BHR occurs in asymptomatic children with FA, its course is milder than that in children with FA and asthma. Factors that determine BHR prevalence in children with FA are similar to those in children without FA.