[Bronchial hyperreactivity or broncho obstructive hyper response]

In this article bronchial hyperreactivity (BHR) is defined and a series of factors which may be involved are discussed: genetic, neurovegetative imbalance, increase in the bronchial epithelial permeability, inflammation and mechanical factors which cause the shortening of the bronchial smooth muscle. A less rigid bronchial cartilage and a decrease in pulmonary elasticity, as well as a thickening of the bronchial wall due to a relative hypertrophy of the glandular tissue might just explain the occurrence of bronchial hyperreactivity in breast-feeding newborns, which actively wheeze and later outgrow the abnormality, and those cases of persistent BHR who repeatedly wheeze. This hyperbronchial response reappears with the aging of the lung tissue.