[Rheological and biochemical properties of sputum. Role of infection (author's tansl)].

Rheological and biochemical changes in sputum following repeated bronchial infections have been studied in six chronic bronchitics. Secretory IgA (IgAs) in the sputum decrease and serumalbumin increases as the number of acute bronchial infection episodes increases. Rheological properties of sputum follow a comparable course to that of secretory IgA. The decrease of the ratio-IgA-serum albumin and the loss of the viscoelastic properties of sputum reflect the non functional state of the bronchial mucosa. These changes may be considered as possible important factors altering mucus clearance and therfore favoring chronic bronchial obstruction.