Trace element levels in adult patients with proteinuria.

AIM: Trace elements are involved in many metabolic processes. They circulate prevalently bound to protein. In literature few studies deal with metal metabolism in adult patients with proteinuria, so we decided to further investigate metal metabolism in proteinuric patients. METHODS: We studied 27 patients (14 male, 13 female), mean age 61.6+/-17 years with different degrees of renal function, serum albumin and proteinuria. Metal concentrations of copper (Cu), zinc (Zn) and aluminum (Al) were measured in serum and urine. No patient had environmental exposure to these metals. RESULTS: The serum Zn level was below the normal range in 11 patients. The serum Cu level was reduced in 5 patients. The Al serum level was elevated in 4 patients. Six patients had reduced and 6 patients had elevated Zn excretion. The urinary Cu excretion was elevated in 6 patients. The urinary Al excretion was elevated in 1 patient. Trace metal concentrations were related neither to renal function nor to total serum protein or albumin levels. Serum zinc was directly correlated with proteinuria and urinary zinc and negatively correlated with testosterone levels in both sexes. CONCLUSION: Adult patients with proteinuria have several modification of trace metal concentration in serum and urine. Serum concentration of metals did not depend on renal function or serum protein levels. Urinary Zn excretion was directly related to proteinuria and serum Zn levels. A negative correlation between serum Zn levels and testosterone was found in both sexes. Renal failure reduced urinary excretion of Cu and Al.

Dialysis hypersensitivity: a fading problem?

Allergic-type reactions experienced by patients on chronic hemodialysis are frequently reported in the literature, often related to compounds released during the hemodialysis sessions, in particular ethylene oxide (ETO). In these studies, dialysis patients seem to have higher values of IgE than those observed in a reference population. The aim of our work was to investigate IgE-related parameters of 126 dialysis patients in comparison with two control groups composed of healthy subjects and predialysis patients. IgE values were not significantly different in nonallergic dialysis patients, with a geometric mean (X) of 27.5 kU/l, when compared to healthy controls (X = 38 kU/l) and predialysis subjects (X = 40.7 kU/l). Higher values of IgE (X = 74.1 kU/l) were detected in allergic dialysis patients. However, only 3 patients, all without detectable antibodies against ETO, complained of anaphylactic symptoms during dialysis sessions in a 4-year surveillance period. At variance, 6 symptom-free patients carried IgE antibodies against ETO (range 0.7-15 kU/l), usually with high total IgE. Our results suggest a reduced frequency of hypersensitivity reactions during dialysis sessions. Furthermore, uremia does not alter IgE reactivity in the predialysis period or after long-term maintenance dialysis treatment.