This finding parallels observations by Lin et al. [9], who reported lower plasma kallistatin in septic shock versus sepsis and linked Day 1 levels to mortality, as well as Kim et al. [10] and Lin et al. [11], who found reduced kallistatin associated with increased mortality, septic shock, and ARDS in community-acquired pneumonia cohorts. Here, SERPINA4 is linked to acute respiratory distress syndrome.