Elevated levels of plasma hyaluronan in septicaemia

Hyaluronan (hyaluronic acid) is normally rapidly cleared from the circulation by the endothelial cells in the liver sinuoids, which make up part of the reticulo-endothelial system (RES). An impaired RES function in severe infection and sepsis might therefore lead to elevated hyaluronan plasma levels. Thus, plasma concentrations of hyaluronan were analysed in 44 patients with severe infection at onset of disease and twice during the following 2-3 days. The patients were divided with respect to severity of disease; no septic shock (n = 29), group 1), septic shock survivors (n = 7, group 2), and septic shock non-survivors (n = 8, group 3). Patients in group 1 showed significantly higher values of plasma hyaluronan on day 1 (p less than 0.05) compared with controls. There was no significant difference on the following two sampling occasions. Patients with septic shock (groups 2 and 3) showed higher values than both controls (p less than 0.001) and patients with severe infection without septic shock (group 1, p less than 0.001) at all three sampling occasions. Non-survivors of septic shock (group 3) had significantly higher values than survivors (group 2), (p less than 0.01-0.05). Septic shock, and especially fatal septic shock, thus appears to be associated with elevated plasma hyaluronan concentrations. Possible mechanisms might be an increased release of the polysaccharide from the interstitial space to the bloodstream, or a decreased rate of clearance by liver endothelial cells. This question demands further study.