Kim S Joseph, Goldstein Marc, Szabo Tamas, Pierratos Andreas
Division of Nephrology, Humber River Regional Hospital, University of Toronto, Toronto, Ontario, Canada.
Am J Kidney Dis. 2003 Mar;41(3):E12. doi: 10.1053/ajkd.2003.50139.
Derangements in bone mineral metabolism are an invariable consequence of end-stage renal disease (ESRD). Extraosseous tumoral calcification is a relatively uncommon complication that can be associated with substantial morbidity.
The authors report a case of an ESRD patient who had severe tumoral calcification of his shoulder, hands, and feet despite daily conventional hemodialysis. Conversion to daily nocturnal hemodialysis (DNHD) led to a dramatic resolution of his calcific deposits within only 9 months of initiating this form of renal replacement therapy.
After initiating DNHD, the patient's serum phosphate level, which had been exceedingly difficult to control, normalized within the first week. Despite maintaining a high dialysate calcium (Ca) bath up to 4.2 mEq/L (2.1 mmol/L; to maintain calcium balance and suppress parathyroid hormone [PTH]), there was ongoing dissolution of the calcific deposits. This occurred with relatively preserved bone mineral density. The Ca x phosphorus (PO4) product decreased from 85 mg2/dL2 (6.80 mmol2/L2) and remained less than 55 mg2/dL2 (4.4 mmol2/L2) throughout the patient's course on DNHD. PTH levels fell precipitously early on but then rose again several months after starting DNHD. This PTH rebound as well as the possible mechanisms underlying the dissolution of this patient's extraosseous calcifications are explored further.
Extraosseous tumoral calcification associated with ESRD is an uncommon but potentially serious complication in this patient population. DNHD, by offering superior phosphate clearance, can facilitate the dissolution of these calcific deposits over a relatively short period. This effect can be seen despite using high calcium concentration dialysate to maintain calcium balance and mitigate hyperparathyroidism.
骨矿物质代谢紊乱是终末期肾病（ESRD）的必然结果。骨外肿瘤性钙化是一种相对少见的并发症，可伴有严重的发病率。
作者报告一例ESRD患者，尽管每日进行常规血液透析，但肩部、手部和足部仍出现严重的肿瘤性钙化。改为每日夜间血液透析（DNHD）后，在开始这种肾脏替代治疗仅9个月内，其钙化沉积物就显著消退。
开始DNHD后，患者一直难以控制的血清磷酸盐水平在第一周内恢复正常。尽管维持高达4.2 mEq/L（2.1 mmol/L）的高透析液钙浴（以维持钙平衡并抑制甲状旁腺激素[PTH]），钙化沉积物仍在持续溶解。这一过程中骨矿物质密度相对保持稳定。钙×磷（PO4）乘积从85 mg2/dL2（6.80 mmol2/L2）下降，并且在患者接受DNHD治疗的整个过程中一直保持低于55 mg2/dL2（4.4 mmol2/L2）。PTH水平在早期急剧下降，但在开始DNHD几个月后又再次上升。进一步探讨了这种PTH反弹以及该患者骨外钙化溶解的潜在机制。
与ESRD相关的骨外肿瘤性钙化在该患者群体中是一种少见但可能严重的并发症。DNHD通过提供更好的磷酸盐清除率，可在相对较短的时间内促进这些钙化沉积物的溶解。尽管使用高钙浓度透析液来维持钙平衡并减轻甲状旁腺功能亢进，但仍可看到这种效果。
