Median SP-D level in plasma was 21.4 ng/mL [(IQR, 13.2–38.4); mean 27.3 ± 19.6 ng/mL] in the group of patients with direct ARDS and 16.3 ng/mL [(IQR, 9.7–38.3); mean 24.3 ± 18.4 ng/mL] in the group of patients with indirect ARDS. Here, SFTPD is linked to acute respiratory distress syndrome.