XDH and acute respiratory distress syndrome: The major findings of our study are: (i) XDH variants may increase the risk of sepsis and renal dysfunction as well as risk of death in sepsis-associated ARDS; (ii) XOR activity may serve as a biomarker for evaluating disease prognosis, and (iii) knowledge of XDH SNPs could potentially identify sub-groups that might benefit from development of targeted therapies to improve clinical outcomes.