Trace elements in end-stage renal disease - 2. Clinical implication of trace elements

For human beings trace elements are essential nutrients with a gamut of fun ctions. They are for instance indispensable components of many enzymes, so they have some regulatory functions and they may affect immune reactions an d free radical generation. Abnormalities of trace elements are primarily th e result of uremia, and they may be further modified and sometimes greatly exacerbated by the dialysis procedure. The role of trace elements in hemodi alysis (HD) patients has not yet been fully characterized. To prevent some complications in chronic HD patients, it is very important to regulate the levels of trace elements by adequate water treatment. Reverse osmosis is ab le to prevent the accumulation of the majority of trace elements in the pat ients. Zinc supplementation may be recommended for patients with proven zin c deficiency, but for all chronic renal failure patients it is questionable . Selenium deficiency is to be suspected in dialyzed patients and selenium supplementation may be beneficial (increasing glutathione peroxidase activi ty, cardioprotective effect, immunostimulatory properties) for chronic rena l failure patients. Supplementation with a trace element may be indicated w hen its depletion was unequivocally documented and when there is evidence o f the positive effects of this element on the quality of life of the dialyz ed patients.