Copper-related blood indexes in kidney dialysis patients.

Previous work has suggested that kidney hemo- dialysis patients could be at risk for either moderate copper defi- ciency or copper toxicity. The present study examined copper- related blood indexes in subjects undergoing hemodialysis treatments with membranes that are not copper-based, in subjects undergoing chronic ambulatory peritoneal dialysis (CAPD), and in control subjects. Both dialysis groups had low plasma copper and ceruloplasmin activities. This occurred despite high plasma inter- leukin 6 concentrations, a situation that usually elevates plasma ceruloplasmin and copper values. CAPD and hemodialysis sub- jects had low ratios of ceruloplasmin activity to immunoreactive protein, and low ratios of plasma copper to ceruloplasmin protein. Both are signs of copper deficiency. In contrast, copper-containing erythrocyte superoxide dismutase (SOD) activities were high in hemodialysis subjects and showed a nonsignificant trend toward high values in CAPD subjects. Blood mononuclear cell copper contents were highly variable within each group, and there were no significant differences between groups. In conclusion, ceruloplas- mm-related indexes in kidney dialysis patients not dialyzed with copper-based membranes suggested a tendency toward moderate copper deficiency. However, this contention could not be con- firmed by erythrocyte SOD activity or mononuclear cell copper measurements. Am J Clin Nuir 1996;64:757-60.