Can Plasma Hyaluronan and Hyaluronidase Be Used As Markers of the Endothelial Glycocalyx State in Patients with Kidney Disease?

Hyaluronan (HA) is widely spread in the body and is an important component of the extracellular matrix, including the endothelial glycocalyx (EG). Essential for its vasculoprotective function, HA is involved in vascular permeability and many other processes. In patients with kidney disease, plasma HA is higher than expected, but the extent to which plasma HA and its degrading enzyme hyaluronidase can be used as markers for the state of the EG has not yet been determined. In the first part of this review, we describe HA synthesis and degradation; we then focus on the involvement of the kidney in the process. In the second part, we summarize the available data on HA and hyaluronidase in patients with kidney failure. Plasma HA is somewhat elevated in kidney failure and predicts for poor survival in dialysis patients. The increased HA levels in kidney failure are probably a result of decreased excretion, but an upregulated turnover cannot be ruled out with certainty in some patients. Hyaluronan might be involved in the regulation of peritoneal transport in PD.