Studies of bronchial secretion. The influence of inflammatory response and bacterial infection.

Bronchial secretions obtained during bronchoscopic examination of 60 children suffering from respiratory tract infections were studied for the concentration of immunoglobulins, anti-proteolytic factors, lactoferrin, and lysozyme. Eleven children having bronchial asthma without a history of chronic or recurrent infections of the respiratory tract were designated as a control. The results were analysed in relation to clinical diagnosis (chronic bronchitis, bronchitis, bronchiectasis) or to the local status of bronchial mucosa at the time of bronchoscopy (no inflammation, inflammation, inflammation with documented bacterial infection). The statistical analysis of the results revealed a decrease of lactoferrin and locally produced IgA in the group of children suffering from bronchitis and chronic bronchitis. Samples infected with Haemophilus species had significantly higher concentration of lactoferrin than any other group. Similarly, albumin in this group was higher than in the other group except that other bacteria were present. Samples infected with Haemophilus also had increased concentrations of S-IgA, IgG, and anti-proteolytic factors when compared with the group without local inflammation.