Effect of 25-hydroxy Vitamin D and Hemodialysis on Vitamin D Axis in Sudanese Renal Failure Patients

Objective: The aim of this study is to investigate the effect of hemodialysis on vitamin D axis through measuring the blood level of25-hydroxyvitamin D, parathyroid hormone (PTH), calcium and phosphate in renal failure patients before and after dialysis compared to their level in healthy subjects.

Materials and Methods: 16 Sudanese patients with renal failure under hemodialysis and vitamin D dose and 16 healthy subjects were involved in this study after informed consent.

Results: The mean of the 25-hydroxyvitamin D concentration in the control, pre dialysis and post dialysis were 0.75, 1.31, and 0.84 μmol/l sequentially. There was no significant difference between the control and post dialysis samples (p-value = 0.44) and there was significant difference between the means of the control and pre dialysis samples (p˂ 0.000) and between the pre dialysis and post dialysis samples (p˂ 0.000). The means of phosphate concentration in the three samples were 3.31, 6.26 and 3.19 mg/dl respectively. Regarding the results of the parathyroid hormone (PTH) and calcium; the means of the PTH in the control, pre dialysis and post dialysis samples were 18.08, 18.01 and 21.96 pg/ml. Concerning the means comparisons, there was no significant difference between all the means. The means of calcium of the three groups were 10.58, 9.96 and 10.14 mg/dl. However, there was no significant variation between the means.

Conclusion: 25-hydroxyvitamin D treatment caused significant increase in the blood concentration of 25-hydroxyvitamin D and phosphate and an insignificant decrease in PTH and calcium.