FBLN1 and Multiple small medullary renal cysts: As for the other proteins, serotransferrin (TF) has been correlated in rat and human urine samples with a risk of renal damage induced by subclinical tubular alterations [55], while Fibulin 1 (FBLN1) could be another possible biomarker of kidney injury, as demonstrated by proteomic studies performed both on sera of patients with different renal diseases [56] and on urinary extracellular vesicles isolated from the urine of patients with medullary sponge kidney disease [57].