Olfactomedin-4 elevation in pediatric acute respiratory distress syndrome

Olfactomedin-4 (OLFM4) was associated with higher mortality, higher probability of dialysis by day 7, and fewer ventilator-free days (VFDs) in a pediatric acute respiratory distress syndrome (ARDS) cohort. In vitro, OLFM4 increased following H3 exposure in undifferentiated neutrophils, which was partly mitigated by toll-like receptor (TLR) antagonism. OLFM4 appears to be a marker, and potentially a mediator, of pathological inflammation and end-organ damage in ARDS.