SERUM BIOMARKERS IN INTERSTITIAL LUNG ABNORMALITIES AND FAMILIAL EARLY INTERSTITIAL LUNG DISEASE

Interstitial lung abnormalities (ILA) are incidental findings at thorax computed tomography in asymptomatic patients that could progress and could be sporadic (ILA) or with a genetic substrate (EARLY interstitial lung disease (ILD)). The aim of this study was to analyse serum biomarkers and clinical behaviour of subjects with ILA (incidental sporadic mild ILD) with healthy controls (Control-ILA) and subjects with mild ILD with a 1 st degree familial ILD (EARLY familial ILD) and without it (familial control-EARLY). Serum levels of KL6, GAL3, CCL18, SPD and αKlotho were quantified by ELISA. Demographic, genetic and pulmonary function tests (PFT) including FVC, TLC, DLCO and 6-minute walking test were evaluated. Correlations were performed between serum biomarkers and functional parameters. Parametric and non-parametric statistical tests were used. p<0.05 was considered statistically significant. ILA patients were older than EARLY ones with a higher proportion of males and less smokers than their controls in both groups. TLC was diminished in ILA compared with their controls (p<0.05). DLCO was decreased in ILA and EARLY compared with their controls (p<0.05). Regarding baseline serum biomarkers, ILA had increased KL6, SPD and α-Klotho compared to their controls, while EARLY had increased KL6 and decreased α-Klotho(p<0.05). A negative correlation between SPD and FVC was observed in EARLY subjects. KL6 and αKlotho in both groups and SPD in ILA are the most altered biomarkers in our cohort. This different profile could impact on ILD progression.