Although patients treated with PMX-DHP tended to have a lower GAP-stage before AE-IPF, there were no significant differences before AE-IPF in PaO2 at rest, 6MWT results, serum levels of Krebs von den Lungen-6 (KL-6) and surfactant protein D (SP-D), or extent score based on HRCT between the two groups. Here, SFTPD is linked to idiopathic pulmonary fibrosis.