Evenepoel Pieter, Claes Kathleen, Kuypers Dirk, Maes Bart, Bammens Bert, Vanrenterghem Yves
Department of Medicine, Division of nephrology, University Hospital Leuven, Belgium.
Nephrol Dial Transplant. 2004 May;19(5):1281-7. doi: 10.1093/ndt/gfh128. Epub 2004 Feb 19.
The natural history of parathyroid function after successful renal transplantation (RT) and the factors predisposing to persistent hyperparathyroidism (HPT) are not well established. A better knowledge of these data may be helpful in the development of algorithms for optimal surveillance and treatment of HPT after successful RT. Our aim was to evaluate the post-transplant natural history of parathyroid function and calcium metabolism in patients with a functional renal graft and to identify risk factors for persistent HPT.
Charts of 1165 allograft kidney recipients transplanted between 1989 and 2000 were reviewed. Patients with an intact parathyroid hormone (iPTH) level available at the time of transplantation were identified. The charts of the latter patients were checked for a variety of demographic and clinical data, and all determinations of the iPTH concentration available since transplantation were recorded. Serum levels of calcium, phosphorus, alkaline phosphatases and creatinine, concurrently determined, were also registered.
After an initial fall, iPTH levels showed a slow but steady decline towards the upper normal limit. The prevalence of persistent HPT, defined as an iPTH level > or =2.5 times the upper normal limit or the need for parathyroidectomy following transplantation, remained stable at approximately 17% up to 4 years after transplantation. Patients with persistent HPT had significantly elevated serum levels of iPTH, calcium and phosphorus at the time of RT, and had spent a longer time on dialysis. Post-transplant iPTH levels correlated significantly with transplant kidney function.
Kidney transplant recipients with a high iPTH and calcium x phosphate product at the time of transplantation are at risk for persistent HPT especially when renal function is suboptimal. Therapy for persistent HPT, if considered, should be initiated 3 months post-transplantation since further spontaneous improvement of parathyroid function thereafter is limited.
肾移植成功后甲状旁腺功能的自然病程以及导致持续性甲状旁腺功能亢进（HPT）的因素尚未完全明确。更好地了解这些数据可能有助于制定肾移植成功后HPT的最佳监测和治疗方案。我们的目的是评估功能性肾移植患者移植后甲状旁腺功能和钙代谢的自然病程，并确定持续性HPT的危险因素。
回顾了1989年至2000年间接受1165例同种异体肾移植患者的病历。确定移植时甲状旁腺激素（iPTH）水平完整的患者。检查这些患者的病历以获取各种人口统计学和临床数据，并记录自移植以来所有可用的iPTH浓度测定值。同时测定的血清钙、磷、碱性磷酸酶和肌酐水平也进行了记录。
iPTH水平在最初下降后，显示出缓慢但稳定地朝着正常上限下降。持续性HPT的患病率定义为iPTH水平>或=正常上限的2.5倍或移植后需要进行甲状旁腺切除术，在移植后4年内一直稳定在约17%。持续性HPT患者在肾移植时血清iPTH、钙和磷水平显著升高，且透析时间更长。移植后iPTH水平与移植肾功能显著相关。
移植时iPTH和钙×磷乘积高的肾移植受者有发生持续性HPT的风险，尤其是当肾功能欠佳时。如果考虑对持续性HPT进行治疗，应在移植后3个月开始，因为此后甲状旁腺功能的进一步自发改善有限。
