Effect of Intermittent Etidronate Therapy on the Prevention of Bone Loss after Kidney Transplantation / 대한내분비학회지

ABSTRACT

BACKGROUND: Osteopenia or osteoporosis is one of the most frequently encountered complications in patients receiving various immunosuppressants after kidney transplantation. The few available preventive strategies for these complications tend to result in various outcomes. In this study, we evaluated the effect of intermittent etidronate therapy for the prevention of bone loss after kidney transplantation. METHODS: Fifty patients who received kidney transplantation for various reasons were recruited and followed for one year. Thirty-eight of these patients commenced etidronate treatment 7 days after operation, the other 12 were followed without etidronate therapy. The treatment consisted of 400mg of etidronate administered orally for 14 days, then repeated four-times every three months. Blood chemistry, iPTH and aluminium levels were tested periodically in all patients. Also checked were bone mineral density of the lumbar spine(L2-4) and femur at baseline, 6 and 12 months after kidney transplantation, as well as D-L spine lateral x-ray at baseline and 12 months. Serum osteocalcin and urine deoxypyridinoline were measured at baseline, 7 days and then every 3 months. RESULTS: Both the etidronate-treated and control groups showed significant decreases in bone mineral densities of the lumbar spine, femur neck and total femur at 6 and 12 months after kidney transplantation(p<0.005). Bone loss was significantly lower in the etidronate-treated group than the control at 12 months after kidney transplantation; lumbar spine(-3.54% vs. -9.51%, p<0.0005), femur neck (-5.41% vs. -8.91%, p<0.0005), total femur (-7.59% vs. -9.07%, p<0.005). Osteocalcin was decreased and deoxypyridinoline increased in both groups. No significant differences in the level or pattern of osteocalcin and deoxypyridinoline were observed in either group. New radiologic compression fractures were found in two patients of the treated group who exhibited severe osteoporosis at baseline during follow-up. CONCLUSIONS: The intermittent administration of etidronate seems to be effective in preventing rapid bone loss after kidney transplantation. Furthermore, this method is safe and convenient for administration and follow-up. Further studies will be required to elucidate the most effective treatment course for the prevention of fractures after kidney transplantation, especially in patients with established severe osteoporosis.