Interleukin-1 kinetics in hemodialysis.

Interleukin-1 (IL-1) was measured in the plasma and in mononuclear cell (MC) lysates from patients on maintenance hemodialysis (HD) using either cuprophan (CU) or polysulfone (PS) membranes. Basal plasma levels of IL-1 in HD patients were significantly higher than those of uremic patients on conservative treatment or of healthy subjects. In 10 patients on conservative treatment, plasma levels of IL-1 increased significantly after 3 and 6 months of HD. During a single HD session, plasma IL-1 fell to 21% (CU) and 22% (PS) of pre-HD levels. Hemodialysis patients had a significantly higher intracellular IL-1 content than normal controls. During HD, a further increase was seen regardless of the membrane employed. A parallel in vitro study showed that IL-1 produced during HD requires at least 24 hours to be released, and that both CU and PS are able to bind and clear IL-1.