Biomarkers that could predict progression in fibrotic ILD patients include UIP pattern on CT across different entities such as CTD-ILD (8, 49), hypersensitivity pneumonitis (9) and IPAF (50), severity of the disease at baseline such as DLCO, and/or CPI (51) and genetic or molecular biomarkers including MUC5b polymorphisms (52). Here, MUC5B is linked to idiopathic pulmonary fibrosis.