[Chronic bronchitis: rare etiology].

Chronic bronchitis is defined for epidemiologic and clinical purposes as the presence of productive cough for three months in each of two successive years. Based on symptoms, the term 'chronic bronchitis', therefore, does not describe one distinct disease. It is rather a collective name for the clinical manifestation of numerous different congenital or acquired chronic diseases of the trachea, the bronchi and the bronchioli. Cigarette smoking is the most consistently important (and preventable) determinant of chronic bronchitis. There are, however, other rare etiologic factors, including malformations, tumors, recurrent aspirations and bronchiectasis. The latter often occur in association with systemic disorders such as cystic fibrosis, immotile cilia syndrome, immunodeficiency, alpha 1-antitrypsin deficiency and others.