Bronchial hyperresponsiveness in children and adolescents with Crohn's disease.

Pulmonary manifestations have been described in Crohn's disease (CD). Bronchial responsiveness to methacholine (MCh) was evaluated in 14 children with CD with no evidence of airway disease, 10 asthmatics, and 10 healthy subjects. In patients with CD total blood eosinophils and serum IgE were 0.20 x 10(9) x L(-1) (95% CI -1.68 to 2.08) and 138.4 kU x L(-)(1) (95% CI 18.84 to 257.96), respectively. Three patients with CD had positive prick tests. Bronchial hyperresponsiveness (BHR) was demonstrated in 10 patients with CD (71%) and in the asthmatics, but not in control subjects. In patients with CD PD(20) appeared significantly greater than in asthmatics (699 microg [95% CI 238 to 1,115] versus 104 microg [95% CI 37.35 to 293]; p < 0.05), and was not related either to baseline FEV(1) or IgE or eosinophils (r = 0.32; r = -0.5; r = -0.15, p = NS, respectively). Neither activity nor treatment or duration of CD affected BHR. Five nonatopic CD patients underwent a second MCh challenge over a 25-mo period: the PD(20) appeared significantly greater than basal PD(20) (1,941 microg versus 575 microg, p < 0.05, respectively), in the absence of significant changes of disease activity. BHR might be the expression of subclinical airway inflammation, a phenomenon which can be responsible for the development of various pulmonary manifestations in CD.