Similar clinical deterioration like AE-IPF will also occur in almost all the other types of pulmonary fibrosis, especially connective tissue disease-ILD (CTD-ILD), nonspecific interstitial pneumonia (NSIP), drug induced ILD, fibrotic allergic pneumonia and cryptogenic organizing pneumonia (COP) etc. Therefore, this program will also provide insight into the basic research and clinical management of acute exacerbation of other interstitial lung diseases, which is one common problem extensively exists in the area of interstitial lung disease and the key factor in terms of improving patients' quality of life and survival.