Urology Division, Kidney Transplant Service - Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo (HCFMUSP), São Paulo, Brazil.
Nephrology Division, Laboratório de Fisiopatologia Renal (LIM16) - Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo (HCFMUSP), São Paulo, Brazil.
BMC Nephrol. 2024 Oct 26;25(1):381. doi: 10.1186/s12882-024-03827-0.
Living kidney donors (LKD) experience an abrupt decline in glomerular filtration rate (GFR) resulting in abnormalities of mineral and bone metabolism (MBD), and this may have implications for skeletal health. We prospectively studied acute and long term MBD adaptation of LKD from two kidney transplant centers (São Paulo, Brazil and Miami, USA).
Renal function and MBD parameters longitudinally after kidney donation (baseline - D0, day 1, 14, 180 and 360 post-operatively) were measured in 74 patients (40 y, 73% female, 54% Brazilian). A subset of 20 donors from Brazil were reassessed after 10 years of nephrectomy.
At baseline, Brazilian donors presented lower intact FGF23 (20.8 vs. 80.1 pg/mL, P < 0.01) and higher PTH (47.4 vs. 40.1, P = 0.04) than their US counterparts. GFR decreased to 63% of its baseline levels just after donation but improved 10% during the first year. PTH levels increased on D1, returning to baseline levels on D14, while FGF23 remained higher than baseline over the first year. LKD had a significant reduction of serum phosphate on D1, which returned to baseline levels on D180. A higher fractional excretion of phosphate (FEP) was noted since D14. After 10 years of donation, 20 LKD presented a sustained reduction in GFR (74.8 ± 14mL/min). There was a return to baseline in serum FGF23 [21.8 (18-30) pg/mL] and FEP, accompanied by an increase in serum calcium. PTH remained elevated (57.9 ± 18 pg/mL), whereas serum calcitriol and Klotho were lower than before the donation.
The abrupt decline in kidney mass is associated with an increase in PTH and FGF23 that is not explained by phosphate retention. In a long-term evaluation, LKD showed a sustained drop in GFR, with lower serum calcitriol and Klotho, and higher PTH. The effects of these changes should be investigated in further studies.
活体供肾者（LKD）的肾小球滤过率（GFR）会突然下降，导致矿物质和骨代谢异常（MBD），这可能对骨骼健康产生影响。我们前瞻性地研究了来自两个肾移植中心（巴西圣保罗和美国迈阿密）的 LKD 的急性和长期 MBD 适应性。
对 74 例患者（40 岁，73%为女性，54%为巴西人）在肾捐献后（基线-D0、术后第 1、14、180 和 360 天）进行了肾功能和 MBD 参数的纵向测量。其中 20 名巴西供者在肾切除 10 年后再次进行评估。
在基线时，巴西供者的全段 FGF23（20.8 vs. 80.1 pg/mL，P < 0.01）和 PTH（47.4 vs. 40.1，P = 0.04）均低于美国供者。GFR 在捐赠后仅下降到其基线水平的 63%，但在第一年增加了 10%。PTH 水平在 D1 升高，在 D14 时恢复到基线水平，而 FGF23 在第一年仍高于基线。LKD 在 D1 时血清磷酸盐显著下降，在 D180 时恢复到基线水平。自 D14 以来，发现磷酸盐的分数排泄率（FEP）更高。在捐赠 10 年后，20 名 LKD 的 GFR 持续下降（74.8 ± 14 mL/min）。血清 FGF23 [21.8（18-30）pg/mL]和 FEP 恢复到基线，同时血清钙增加。PTH 仍升高（57.9 ± 18 pg/mL），而血清 1,25-二羟维生素 D3 和 Klotho 低于供肾前。
肾脏质量的突然下降与 PTH 和 FGF23 的增加有关，而这种增加不能用磷酸盐的保留来解释。在长期评估中，LKD 的 GFR 持续下降，血清 1,25-二羟维生素 D3 和 Klotho 降低，PTH 升高。应在进一步的研究中调查这些变化的影响。
