Abstract:

Objective To find high-specific serum biomarkers for the diagnosis and prognosis monitoring of interstitial lung disease（ILD）. Methods A total of 134 ILD patients,including 124 patients with connective tissue disease interstitial lung disease （CTD-ILD）,were enrolled,and 48 patients with ordinary pneumonia, 22 patients with chronic obstructive pulmonary disease（COPD）,38 patients with lung cancer and 9 patients with other pulmonary diseases were enrolled as well. Totally,30 healthy subjects were enrolled as healthy control group. Krebs Von den Lungen-6 （KL-6）,matrix metalloproteinase-3 （MMP-3）,fibronectin （FN） and C-reactive protein（CRP） were determined. Receiver operating characteristic （ROC） curve was used to evaluate the diagnostic efficiency of KL-6 for ILD. Results Compared with healthy control group,the KL-6 levels of ILD,lung cancer and ordinary pneumonia groups were higher （P<0.01,P<0.05）,and the KL-6 level of ILD group was the highest. The FN levels of ILD,ordinary pneumonia and COPD groups decreased （P<0.01）. CRP increased in all pulmonary disease groups（P<0.01）. ROC curve analysis showed that the area under curve of KL-6 for the diagnosis of ILD was 0.814. The optimal cut-off value for the diagnosis of ILD was 430 U/mL,the sensitivity was 59.4%,and the specificity was 89.8%. The MMP-3 level of ILD group was 155（84.5-290.5） ng/mL,which was 2-15 times higher than normal reference range provided by manufactories. The positive rate of MMP-3 in CTD-ILD group was 84.7%. Conclusions High-specific serum biomarkers,KL-6 and MMP-3,can improve the diagnostic efficiency for ILD and CTD-ILD.

Key words: Krebs Von den Lungen-6, Matrix metalloproteinase-3, Fibronectin, C-reactive protein, Interstitial lung disease