Abstract: Objective To observe the influences upon serum calcium and parathyroid hormone (PTH) by adjusting the dialysate calcium concentration in hemodialysis (HD) patients. Methods Serum calcium and intact PTH levels in twenty-three HD patients were observed when their dialysate calcium concentration was adjusted. These patients were divided into two groups by their initial serum calcium levels: hypocalcaemia group and normal calcaemia group.Results One month after increasing the dialysate calcium concentration from 1.25 to 1.5mmol/L, the serum calcium was increased [from (1.92±0.15) to (2.06±0.12)mmol/L，P＜0.001) and serum iPTH level was decreased [from (615±305) to (306±180) pg/ml，P＜0.001) in the hypocalcaemia group; The serum calcium and serum iPTH level were not significantly changed in the normal calcemia group. Conclusion Increasing dialysate calcium concentration is helpful to the HD patients who have both hypocalcemia and high serum PTH levels.

Key words: Serum calcium, Hemodialysis, Dialysate