Abstract

Introduction:

The identification of serum biomarkers for the differential diagnosis between interstitial lung disease  associated with autoimmune diseases (AD-ILD) and idiopathic pulmonary fibrosis (IPF) is of potential interest. Endothelin-1 (ET-1) is a pleiotropic molecule that plays a key role in endothelial dysfunction and lung fibrosis, characteristic processes of AD-ILD and IPF [1-2]. Accordingly, it is plausible to consider ET-1 as a biomarker for the differential diagnosis between both diseases.

Objective:

To determine the use of ET-1 for the differential diagnosis between AD-ILD and IPF patients.

Methods:

115 patients with IPF, 104 with AD-ILD, 45 with different AD and 49 healthy controls (HC) were included. ET-1 serum levels were determined by enzyme-linked immunosorbent assay.

Results: 

Similar ET-1 serum levels were found between AD-ILD and IPF patients (AD-ILD: mean 1.43 pg/mL, IPF: 1.36 pg/mL). Interestingly, an increase of ET-1 levels was observed in patients with AD-ILD and IPF compared to AD patients (AD:1.01 pg/mL, p<0.001 in both cases). This increase was more evident when AD-ILD and IPF patients were compared to HC (HC: 0.84 pg/mL, p<0.001 in both cases).

Conclusion:

Serum ET-1 may not be useful as biomarker for the differential diagnosis between AD-ILD and IPF, although it could help to evaluate the presence of ILD in AD patients.

References:

[1] Mayes,M.D. Arthritis Rheum 2003;48:1190-9

[2] Ross,B. Am J Respir Cell Mol Biol 2010;42:16-20

Acknowledgements: Study supported by FUAM20/32 (Cátedra UAM-Roche EPID Futuro) and SEPAR 474-2017. Personal funds, SR-M and VP-C: RD16/0012/0009 (ISCIII-ERDF); RL-M: CP16/00033 (ISCIII-ESF).