Hyaluronan serum concentrations are elevated in critically ill patients and associated with disease severity

► Hyaluronan (HA) is a biomarker in chronic liver disease by reflecting matrix proteins. ► HA is significantly elevated in critically ill patients compared to healthy controls. ► Highest HA levels found in ICU patients with liver cirrhosis or patients with sepsis. ► HA levels correlate with biomarkers of organ dysfunction and systemic inflammation. ► HA levels reflect severity of critical illness.