Cathepsin B only displayed a moderate diagnostic capacity to detect fibrosis in F1 patients, AUROC = 0.68 ± 0.09 (95%CI = 0.51–0.86; p = 0.035), but cathepsin B also showed excellent diagnostic power to detect intermediate levels of fibrosis in F2 patients (AUROC = 0.992 ± 0.006) and advanced liver fibrosis in F3 (AUROC = 0.98 ± 0.01) and F4 patients (AUROC = 0.95 ± 0.02). Here, CTSB is linked to fibrosis.