Fig. 3.

Receiver operating characteristic curve for serum levels of HSP47, KL-6, SP-A, SP-D and LDH in patients with S-IPF and AE-IPF. The cut-off level for HSP47 that resulted in the highest diagnostic accuracy was 559.4 pg/mL, which discriminated between AE-IPF and S-IPF with 100.0 % sensitivity and 93.9 % specificity; diagnostic accuracy was 96.2 %. Use of serum HSP47 level for diagnosis of AE-IPF resulted in the largest area under the curve (0.989) compared to use of serum levels of KL-6, SP-A, SP-D and LDH (0.597, 0.591, 0.583 and 0.841, respectively)