The effect of low-dose cholecalciferol and calcium treatment on posttransplant bone loss in renal transplant patients: a prospective study.

Background/aim: Posttransplant steroid doses have been reduced with the use of new and potent immunosuppressive agents. However, posttransplant osteoporosis is still a serious problem. Our aim in this study was to investigate the effect of low-dose cholecalciferol and calcium supplementation on bone loss after transplantation in renal transplant patients.

Methods: Fifty-eight renal transplantation patients were included in the study. Fourteen newly transplanted patients (group 1) and 44 renal transplantation patients with a graft age of at least six months (group 2) were involved. All patients received 400 IU/day orally cholecalciferol (vitamin D3) and 600 mg/day orally calcium replacement starting from the second day posttransplantation. All patients baseline serum and urine biochemistry, serum 25-hydroxy vitamin D3 (25 (OH)D3), and bone mineral density (BMD) tests were performed. Also, the same measurements were performed at the 12th month in group 1.

Results: After one year of treatment, BMDs were improved in group 1. Patients in group 1 had a nonsignificant increase of lumbar spine (8.12 +/- 18.64% of baseline BMD) and femoral total (7.10 +/- 13.48% of baseline BMD) BMD at the end of the first year. On the other hand, there was a significant increase in femoral neck (10.06 +/- 15.70% of baseline BMD, p < 0.05) measurements. The baseline results of group 2 were similar to group 1. In group 1, 25 (OH)D3 levels were increased while PTH levels were decreased at the end of the year.

Conclusion: In renal transplant patients who use low-dose metilprednisolon and new immunosuppressive agents together, low doses of vitamin D3 and calcium replacement for one year provides a reduction in lumbar spine, femoral neck, and femoral total bone loss and prevents bone loss in group 2. In addition, it contributed to the normalization of PTH levels.