Acetate free citrate-containing dialysate increase intact-PTH and BAP levels in the patients with low intact-PTH

BACKGROUND Recently, acetate-free citrate containing dialysate (A(-)D) was developed. We have already reported about the significant effect of A(-)D on metabolic acidosis, anemia, and malnutrition in maintenance hemodialysis (MHD) patients. In this study, we compared the effect of A(-)D and acetate containing dialysate (A(+)D) on serum calcium and intact-parathyroid hormone (int-PTH) levels. METHOD Single session study: Seventeen patients were treated with A(+)D in one session and also treated with A(-)D in another session. Serum levels of pH, HCO3-, total (t)-calcium, ionized (i)-calcium, and int-PTH were evaluated at the beginning and the end of each session. Cross over study: A total of 29 patients with MHD were treated with A(+)D for 4 months, switched to A(-)D for next 4 months, and returned to A(+)D for the final 4 months. RESULTS In single session study, serum i-calcium and t-calcium levels significantly increased, and int-PTH levels decreased after HD with A(+)D, whereas HD with A(-)D did not affect iCa and int-PTH. In cross over study, if all patients were analyzed, there was no significant difference in serum int-PTH or bone alkaline phosphatase (BAP) levels during each study period. In contrast, in the patients with low int-PTH (<60 pg/mL), serum levels of int-PTH and BAP were significantly increased during the A(-)D, without significant changes in serum t-calcium or i-calcium levels. CONCLUSION A(-)D containing citrate could affect calcium and PTH levels, and, in 4 month period of crossover study, increased int-PTH levels pararelled with increasing BAP levels, exclusively in MHD patients with low int-PTH levels.