[A study of interstitial pneumonia associated with collagen vascular disease--comparison with the data of idiopathic pulmonary fibrosis].

To clarify the pathogenesis of idiopathic interstitial pneumonia (IIP), we compared the data of interstitial pneumonia (IP) associated with collagen vascular disease (CVD) with those of idiopathic pulmonary fibrosis (IPF). These disorders are found to have similar clinical, radiographic, and morphological findings, and lung function. However, the in vitro behavior of fibroblasts from CVD-IP and IPF, and the detection of soluble ICAM-1 were different. Further, in the T cell receptor repertoire, the predominance of different genes was found in bronchoalveolar lavage cells from CVD and IPF. These differences could partly explain the variability of IP pattern seen in CVD. In summary, our results indicate the possibility that CVD-IF and IPF result from different mechanisms although they share the same spectrum of pulmonary changes.