The pathogenesis of bronchial catarrh and of acute and chronic bronchitis.

""Chronic bronchitis " has recently been discussed from many points of view, all of them important enough, but very little has been said about the aetiology and pathogenesis of the condition. Investigations into the late stages of the disease, clinically, radiologically, or anatomically, do not show the course of the affliction, and, important as it may be to investigate the bacteriology, the effect of antibiotics, or the social conditions, nothing of this kind will elucidate the pathogenetic progress. On the other hand, especially in view of the growing incidence and danger of chronic bronchitis and bronchial carcinoma, it is necessary to investigate in a more detailed way the much neglected field of the normal and morbid anatomy of the bronchi. An attempt is therefore made in this paper to explain the basic pathogenetic factors and not to deal with acute exacerbations and their treatment.