Abstract: TH-PO1051

Influence of Dialysis Vintage on Mineral and Bone Disorders after Kidney Transplantation

Session Information

Category: Mineral Disease

  • 1201 Mineral Disease: Ca/Mg/PO4

Authors

  • Kono, Keiji, Kobe University Graduate School of Medicine, Kobe, Japan
  • Fujii, Hideki, Kobe University Graduate School of Medicine, Kobe, Japan
  • Nakai, Kentaro, Fukuoka Red Cross Hospital, Fukuoka, Japan
  • Hosokawa, Nozomi, Kobe University Graduate School of Medicine, Kobe, Japan
  • Goto, Shunsuke, Kobe University Graduate School of Medicine, Kobe, Japan
  • Nishi, Shinichi, Kobe University Graduate School of Medicine, Kobe, Japan
Background

Mineral and bone disorder (MBD), such as hypercalcemia and hypophosphatemia, frequently occurs after kidney transplantation (KT), and its evidence has accumulated. However, the relationship between pre-KT dialysis vintage and post-KT MBD has not been evaluated in the detail.

Methods

Ninety-six patients who underwent KT were included. Patients with parathyroidectomy during pre-KT and the 12 months post-KT were excluded. We compared the natural history of post-KT MBD between pre-emptive KT (PKT) and non-PKT. Furthermore, non-PKT group was divided into 3 groups according to the dialysis vintage; <3years, 3-6years, >6years. Parameters of MBDs and kidney function were followed at pre-KT, 1 and 2 weeks, and 1, 2, 3, 6 and 12 months post-KT. We also checked pre-KT parathyroid enlargement by ultrasound evaluation.

Results

Serum calcium levels increased and reached a plateau at the 2 months post-KT in all the groups. Patients with longer dialysis vintage had higher serum calcium levels from the 1 week post-KT, and particularly the group with dialysis vintage > 6 years had persistent hypercalcemia, which was significantly higher serum calcium levels from the 1 month to 12 months post-KT compared to the other groups. Serum phosphate levels substantially decreased until the 1 week post-KT, after which it gradually increased in all the groups. The non-PKT group had significantly lower serum phosphate levels compared to the PKT group from the 1 week to 3 months post-KT, but there was no significant difference depending on dialysis vintage. PTH levels were significantly higher in the PKT group compared to the non-PKT group at pre-KT, but substantially decreased in the PKT group to almost the same levels as the other groups until the 1 month post-KT. The group with dialysis vintage > 6 years had higher prevalence of pre-KT parathyroid enlargement and persistent higher PTH levels during the 12 months post-KT, and its levels were significantly higher at the 12 months post-KT compared to the other groups. Kidney function was comparable among all the groups during the 12 months post-KT.

Conclusion

Our findings suggest that patients with longer dialysis vintage have persistent higher serum calcium levels just after KT, and its levels are significantly higher especially in dialysis vintage > 6 years probably due to persistent hyperparathyroidism.