Tracheobronchial aspirate fluid neutrophil lipocalin, elastase- and neutrophil protease-4-α 1 -antitrypsin complexes, protease inhibitors and free proteolytic activity in respiratory distress syndrome

Abstract

Free proteolytic or elastolytic activity in the TAF of RDS infants in the first week of life occurred by way of exception. Elastase-/NP4-alpha1AT complex or neutrophil lipocalin levels were not correlated with the development of CLD. The correlation between CLD and low alpha1AT or ACT at 3-4 d and SLPI at 7-8 d of age may be due to either immaturity or complex formation. The severity of RDS as judged from radiological examination was correlated with elastase-alpha1AT complex on day 3-4. The main hypothesis, that TAF protease/protease inhibitor levels or imbalance and leucocyte activity are important factors indicating a high risk of severe RDS and subsequent CLD development, was principally not confirmed.