[Evaluation of the elastase burden in patients with idiopathic interstitial pneumonia]

This study was designed to clarify the role of neutrophil elastase in the pathogenesis of idiopathic interstitial pneumonia (IIP). To accomplish this, elastase: alpha 1-antitrypsin complexes in plasma and bronchoalveolar lavage fluids (BALF) were measured in 19 patients with IIP and compared to 15 normal smokers. Cell differentiation counts showed that there was no difference in percent neutrophils in BALF between IIP patients and normal smokers. However, elastase: alpha 1-antitrypsin complexes were significantly increased in both plasma and BALF in patients with IIP compared to normal smokers. In IIP patients with honeycombing demonstrated by high resolution CT, although elastase: alpha 1-antitrypsin complexes were not significantly increased in plasma, elastase: alpha-antitrypsin complexes in BALF were significantly increased compared to IIP patients without honeycombing. Western immunoblot analysis showed that although the native 80-KD elastase: alpha-antitrypsin complex was detected in BALF, the molecular weight of elastase: alpha 1-antitrypsin complex in plasma was 60-KD.