EVIDENCE OF TAURINE DEPLETION AND ACCUMULATION OF CYSTEINESULFINIC ACID IN CHRONIC DIALYSIS PATIENTS

Methionine, taurine and cysteinesulfinic acid (CSA) were determined by reversed-phase high-performance liquid chromatography (RP-HPLC) in pl asma from ten patients treated with hemodialysis (HD) and eight patien ts treated with continuous ambulatory peritoneal dialysis (CAPD). The patients' data were compared with data obtained from ten healthy contr ols. Significant reductions in plasma taurine levels were observed in the HD patients (34 +/- 13 mu mol/liter, mean +/- SD) and the CAPD pat ients (47 +/- 12 mu mol/liter) compared to the controls (66 +/- 5 mu m ol/liter), while the CSA levels were markedly higher in the HD patient s (9.1 +/- 2.8 mu mol/liter) and the CAPD patients (9.1 +/- 2.4 mu mol /liter) than in the controls (0.79 +/- 0.15 mu mol/liter). A single HD treatment significantly reduced the plasma taurine and CSA concentrat ions (P < 0.01 and P < 0.001), respectively. The plasma methionine lev els were normal in both patient groups. The finding of a low plasma ta urine level and a large accumulation of CSA suggests that the metaboli c conversion of CSA to taurine is impaired in uremic patients and this metabolic abnormality may cause taurine depletion.