Patients undergoing dialysis have an impaired glycocalyx barrier and elevated levels of its constituents in their blood, according to a study published online in the Journal of the American Society of Nephrology.
Carmen A. Vlahu, MD, of the Academic Medical Center in Amsterdam, and colleagues used Sidestream Darkfield imaging to detect changes in glycocalyx dimension in dialysis patients and healthy controls based on in vivo recordings of the sublingual microcirculation.
The researchers found that dialysis patients had increased perfused boundary region and perfused diameters, consistent with deeper penetration of erythrocytes into the glycocalyx. Dialysis patients also had elevated serum levels of the glycocalyx constituents hyaluronan and syndecan-1, as well as increased hyaluronidase activity. The imaging parameters were not influenced by loss of residual renal function, but there was an association with greater shedding of hyaluronan in blood. Higher levels of inflammation in patients correlated with more significant damage to the glycocalyx barrier.
“In conclusion, in this study, we show that dialysis patients have loss of glycocalyx barrier properties as estimated by analysis of the dynamic variations of erythrocyte column width in the sublingual microcirculation,” the investigators stated. “Impaired glycocalyx barrier properties, together with shedding of its constituents into blood, are consistent with sustained pathogenic endothelial cell activation in dialysis patients and probably contribute to the aggressive vascular pathology present in this group of patients.”