Interstitial lung disease is a chronic progressive fibrosis lung disease that with a highly variable clinical process.thence it is significant for the patient to search a convenient and accurate prediction method. The objective of this study was to determine whether peripheral blood biomarkers can predict disease .

The median follow-up period was 12 months, each patient received 4 or 5 follow-ups in our center, 336 person-times in study enrollment totally. The patients with interstitial lung disease had significantly higher serum baseline KL-6 and MMP-7 levels compared with healthy control.They divided into progressive group and non-progressive group according to disease change. Serum KL-6 and MMP-7 levels were elevated in patients if disease progression, but baseline level of biomarkers in progressive group were not significant higher compare with non-progressive group .Binary logistic regression showed △KL-6 and △MMP-7 were significant predictors for disease progression. Multivariate Cox analysis showed KL-6 and MMP-7 were significantly associated with survival along with other variables.

The serum levels of KL-6 and MMP-7 were elevated in the individuals with interstitial lung disease compared with healthy controls. The rate of poor prognosis and mortality more associated with the variability increased biomarker concentrations，rather than the baseline concentration.Therefore，Serial measurements of biomarkers contribute to the disease monitoring in clinical management.

Inclusion Criteriar:

• Clinical diagnosis of interstitial lung disease

Exclusion Criteria:

• Diagnosise of interstitial lung disease acute excerbation
• Combined pulmonary embolism, pulmonary edema, pulmonary tuberculosis, and peumonias

All subjects with a diagnosis of idiopathic interstitial pneumonias made in accordance with the American Thoracic Society (ATS)/European Respiratory Society (ERS) consensus classification