A causal relationship between microcirculation abnormalities and pulmonary fibrosis could be driven by the clinical association of SSc-ILD with digital ulcers,41 capillaroscopy structural changes,42 anti-endothelium antibody positivity43 and increased serum markers of endothelial dysfunction such as E-selectin, P-selectin, von Willebrand Factor Antigen and ICAM1.44,45 Furthermore, the available BALF characterization data consistently show increased levels of endothelin-146 and thrombin47 in SSc-ILD patients. This evidence concerns the gene ICAM1 and systemic sclerosis.