CLINICAL MANIFESTATIONS OF TRACE-METAL ABNORMALITY IN HEMODIALYSIS-PATIENTS - A MULTICENTER COLLABORATIVE STUDY

A multicenter collaboratively study was undertaken involving the preva lence of abnormal blood levels of 6 trace metals (copper, zinc, alumin um, lead, cadmium, and mercury) in hemodialysis patients to observe th eir clinical manifestations. The study involved 6 medical centers and 405 patients with end-stage renal disease who had been on maintenance hemodialysis for at least 4 months. Venous blood samples were collecte d from these patients before initiating hemodialysis. Atomic absorptio n spectrophotometry was used to measure plasma levels of copper, zinc, and aluminum, as well as whole blood levels of lead, cadmium, and mer cury. Additionally, clinical symptoms and other parameters related to intoxication or deficiency of these trace elements were simultaneously assessed. Those results indicated a high proportion of abnormally low plasma zinc levels (19%) and abnormally high aluminum levels (21%) in the 405 hemodialysis patients. A small portion of patients had sympto ms attributed only to abnormally high blood levels of copper (7%) or c admium (7%). The patients did not have any lead or mercury intoxicatio n. Plasma zinc levels decreased with age but increased with dialysis d uration. Female patients had higher levels of plasma copper, blood lea d, and blood mercury than did males. Moreover, no significant influenc e of different dialyzers on plasma or blood levels of these trace meta ls was found. On the basis of the above results, we can conclude that the abnormal metabolism of trace metals contributes to a part of the u remic symptoms unresolved by maintenance hemodialysis. Furthermore, en vironmental factors, diets, and the aging process with its accompanyin g altered gastrointestinal absorption-rather than the hemodialysis pro cedure-are most likely responsible for the trace metal burden found in uremia.