[Bronchial hyperreactivity].

Bronchial hyperreactivity, the abnormal reaction of the airways on non-allergic stimuli, is a feature of patients with chronic nonspecific lung disease. Several underlying mechanisms such as the neurogenic pathways, inflammatory cells and mediators, increased vascular leakage, epithelial damage and pathological changes in airway smooth muscle seem to play a role of importance in bronchial hyperreactivity. Recent developments in these research fields produce more clarity in the mutual connection of these factors in relation to the phenomenon of bronchial hyperreactivity.