[The protease inhibitor system in children (in diseases of the lung, liver and hereditary alpha 1-antitrypsin deficiency)].

The balance of the protease inhibitor system is decisive for the pulmonary conditions of children. Our investigations showed that an imbalance of this system can be interpreted as manifestation of a severe pulmonary inflammation (e.g. deficit of inter-alpha-antitrypsin inhibitor in case of dyspnoe) or it can be regarded itself as a severe disease (alpha 1 antitrypsin deficit). A largely normal protease inhibitor system in children with pulmonary diseases is a point in favour of a clinically bland progression (for instance no protease inhibitor depression in group II = lung diseases). The efforts to compensate for existing inhibitor deficits are distinct (e.g. by the compensatory mechanism of alpha 2 macroglobulin). How and to which extent hepatopathies or the still immature liver in early childhood, for instance by synthesis disturbances, have an effect on the protease inhibitor system cannot be regarded as clarified. For characterization pulmonary inflammatory diseases and alpha 1 antitrypsin deficiency analysis of inhibitors can be efficient.