Increased frequency of bronchial hyperresponsiveness in patients with inflammatory bowel disease

Abstract
Although bronchopulmonary manifestations are rare in inflammatory bowel diseases (IBD), subclinical abnormalities have been described in up to 50% of cases. The pathophysiology of these abnormalities remains unknown. However, a latent inflammation of the bronchial mucosa secondary to the inflammation of the intestinal mucosa has been suggested. This subclinical inflammation may lead to increased bronchial responsiveness. We studied the bronchial responsiveness in 38 inflammatory bowel disease (IBD) patients, using the methacholine test. Bronchial hyperresponsiveness was defined by a PC20M 1 between IBD patients and controls. However, there was a significantly greater fall in FEV1 in the IBD patients at the concentrations of methacholine tested. The frequency of bronchial hyperresponsiveness was significantly higher in the IBD population (45%) than in controls (17%; PP<0.02). Thus, subclinical bronchial hyperresponsiveness is common in IBD, and may be considered a further extraintestinal manifestation.