Figure 4
From: Cleaved cytokeratin-18 is a mechanistically informative biomarker in idiopathic pulmonary fibrosis
Serum cCK-18 levels in patients with lung fibrosis. A. Serum cCK-18 level is higher in IPF (n=84) than HP (n=24), NSIP (n=22), or control subjects (n=39); p ≤ 0.001 for comparison of IPF with all subgroups). cCK-18 level is similar in HP, NSIP, and control subjects. B. cCK-18 distinguishes IPF from other fibrotic ILDs (area under the receiver operating characteristic curve [AUC] = 0.76). Sensitivity (Sn), specificity (Sp), and likelihood ratios (LR) are shown for the diagnosis of IPF (versus HP and NSIP) using several cCK-18 thresholds. A cut-off of 115 units per liter (dashed line) provided the highest AUC (0.76). * Four outliers are excluded from the IPF group for illustrative purposes (cCK-18 values not shown: 433, 513, 979, 1147 units/L).