SSc patients have significant higher serum levels of FGF-23 after Iloprost infusion, both at t1 and t2, compared to HC [10.4 ± 5.5 pg/ml and 8.6 ± 5.1 pg/ml versus 3.6 ± 2.2 pg/ml, p < 0.001]. This evidence concerns the gene FGF23 and systemic sclerosis.