The removal of serum hepcidin by different dialysis membranes.

PURPOSE: Hepcidin has been suspected to be associated with anemia of chronic disease, which is commonly observed in patients with maintenance hemodialysis (MHD). As almost of hepcidin is bounded to protein, it is essential to clarify which kind of dialysis membrane can remove it efficiently.

METHODS: Ex vivo study: 50 mL of whole blood from healthy volunteers were circulated for 2 h in a microcircuit with mini-dialyzers (acrylonitrile-co-methallyl sulfonate (AN69) or polysulfone (PS)) without ultrafiltration. We measured hepcidin-25 levels at 0, 60, and 120 min in the blood samples. In vivo study: Blood samples were taken from 28 MHD patients at the start and end of HD sessions with PS or AN69. We measured serum levels of hepcidin 20, 22, and 25 by liquid chromatography tandem mass spectrometry, and also measured serum levels of urea nitrogen (UN), β2microglobulin (MG).

RESULTS: Ex vivo study: Although serum hepcidin 25 levels increased after the ex vivo session with PS, they significantly decreased with AN69. In vivo study: The reduction ratio of β2MG by PS was significantly higher than that of AN69. On the other hand, there was no significant difference in the reduction ratio of hepcidin 20, 22, and 25 between PS and AN69.

CONCLUSIONS: Both super-flux PS and AN69 similarly removed hepcidin 20 22, and 25. HD with PS might achieve a high removal ratio of hepcidin by enhanced diffusion performance and an increased clearance of small molecule solutes. On the other hand, AN69 might remove hepcidin by adsorption.