Hemodialysis with Regenerated Cellulosic Membranes Does Not Reduce Plasma Selenium Levels in Chronic Uremic Patients

: Selenium (Se) is considered an essential and very important trace element for humans. Se blood levels are frequently low in end-stage renal disease (ESRD) patients, but very little has been established concerning the mechanisms that could modify Se status in uremia, including a supposed dialysis-mediated Se depletion. In order to verify whether hemodialysis (HD) can induce a loss of Se, thereby leading or contributing to a low plasma Se concentration, we investigated the effect of HD procedure with the most commonly used regenerated cellulosic membrane (Cuprophan) on plasma Se levels in 20 uremic patients on HD for 62.5 ± 49.4 months. Plasma Se levels were also determined in 15 chronic renal failure (CRF) nondialyzed patients and in 28 age-matched healthy controls. Se concentration was determined by atomic absorption spectrophotometry. Plasma Se levels of both HD patients (61.3 ± 8.5 μ/L) and CRF nondialyzed patients (56.4 ± 10.1 μg/L) were significantly lower than in normal subjects (78.3 ± 9.7 μg/L, p < 0.001). In CRF nondia-lyzed patients, a significant (p < 0.05) negative correlation was found between the plasma Se concentration versus serum creatinine values. Within the HD group, plasma Se levels significantly increased after the HD procedure (72.8 ± 17.2 μg/L, p < 0.02) together with hemat-ocrit and total plasma protein values (p < 0.05 and p < 0.001, respectively). In the hollow fiber dialyzer during an HD session, the Se concentration increased but not significantly from the blood inflow site (64.6 ± 12.5 μg/L) to the outflow site (72.6 ± 17 μg/L) and decreased, again not significantly, from the dialysate entrance (5 ± 1.9 μg/L) to the outlet (4.8 ± 2.5 μ?.). In HD with low-flux regenerated cellulosic dialyzer, very likely due to the high molecular weight of Se-binding proteins, the replacement treatment did not induce a Se loss in chronic uremic patients with a low plasma Se concentration.