Abstract
Introduction: Vitamin D replacement is recommended for chronic kidney patients as vitamin D prevents the development of secondary hyperparathyroidism. However, the optimal vitamin D level or dosage is controversial. In this study, we investigated the basal vitamin D levels in patients undergoing hemodialysis, and effects of high dose vitamin D supplements on serum Vitamin D, parathormone (PTH), calcium (Ca), phosphorus (P), alkaline phosphatase (ALP), C-reactive protein (CRP), and albumin test levels.
Materials and Methods: 61 patients who have been in the routine hemodialysis program for at least six months in Usak University Training and Research Hospital included in the study. The demographic characteristics of the patients, 25(OH) vitamin D, PTH, Ca, P, ALP, albumin, CRP levels collected from the patient records before and after three months of high dose vitamin D (150.000-300.000IU) replacement. The data obtained in this study analyzed with SPSS 21 package program.
Results: 31 of the patients were female, 30 were male. The mean age of the patients was 63.39±13.76. Vitamin D level was insufficient or deficient in 95.2% of the patients. Only there was a statistically significant correlation between basal vitamin D levels and dialysis duration (p<0.05). There was no significant difference between the PTH, Ca, P, ALP, and CRP levels of patients before and after vitamin D replacement, but there were a significant difference in serum albumin and vitamin D levels (p<0.005).
Conclusion: Although vitamin D treatment is necessary for chronic kidney patients undergoing dialysis, more clinical studies are needed to bring standardization regarding the dosage and duration of administration.

Key words: Hemodialysis, vitamin D, bone turnover