Collagen type III biomarker levels according to interstitial fibrosis and tubular atrophy in IgAN patients. Serum and urinary levels of C3M (A), C3C (C), and PRO-C3 (E) in IgAN patients, according to the Banff score (ci0–ci3). Serum and urinary levels of C3M (B), C3C (D), and PRO-C3 (F) according to the T-score (T0–T2). Data are presented on a log10-scale as median with IQR and statistical differences were assessed by Kruskal–Wallis test; * p < 0.05, ** p < 0.01, **** p < 0.0001. Black symbols corresponds to black y-axis (left, ex S-PRO-C3) and grey right y-axis (ex U-PRO-C3/Cr) and the figures are divided by a dotted line in the middle.