RESUMO
INTRODUCTION: Serum levels of ß2-microglobulin (b2M) are significantly higher in patients with end stage renal failure undergoing hemodialysis (HD) and its accumulation accelerates Dialysis Related Amyloidosis (DRA). In HD patients low-flux dialysis, intravenous (IV) iron (administered for the treatment of anemia) affects ß2M removal during dialysis. IV iron also affects the oxidation of plasma proteins, including b2M. AIMS: To examine the effect of intravenous iron therapy on ß2M levels and oxidation in HD patients treated with high-flux compared with low-flux dialyzers. METHODS: Sixteen HD patients on chronic maintenance IV iron therapy were studied. Half of the patients were allocated to high-flux and half to low-flux dialysis. After five weeks, each patient was assigned to the second dialyzer. After two weeks of treatment with each dialyzer, blood samples were taken and serum levels of ß2M were measured. In addition, the hematocrit and iron status were measured. Part of the samples were used to evaluate oxidized ß2M. RESULTS: A significant increase in ß2M levels was found with low-flux dialysis, which further increased during dialysis with IV iron administration. High-flux dialysis therapy significantly lowered the ß2M levels, with a clear decrease during the dialysis session, that was unaffected by IV iron administration. A significant decrease in ß2M oxidation was found during highflux, but not low-flux dialysis. CONCLUSIONS: High-flux dialysis is more effective than lowflux in decreasing the levels and oxidation of ß2M. These observations may have significance in improving iron therapy, aimed to decrease or attenuate the appearance of DRA.
