Protease-antiprotease imbalance: local evaluation with bronchoalveolar lavage.

The protease-antiprotease imbalance is thought to be involved in a variety of destructive lung diseases: pulmonary emphysema, chronic bronchitis, cystic fibrosis and adult respiratory distress syndrome. Bronchoalveolar lavage allowed the investigators to assess the protease-antiprotease shift in such conditions but sometimes gave conflicting results. The role of bronchoalveolar lavage as a research and diagnostic tool in diseases characterised by protease-antiprotease imbalance is reviewed, as well as its potential usefulness in the near future.