THBD and acute respiratory distress syndrome: Plasma levels of thrombomodulin were higher in the flu syndrome with the ARDS group [1411 pg/ml (IQR 878–2237)] and flu syndrome without the ARDS group [1390 pg/ml (IQR 21–17460)] compared to the control group [219 pg/ml (IQR 21–601)], p = 0.0001.