Lotfollahi Legha, Ossareh Shahrzad, Neyestani Tirang R
Hasheminejad Kidney Center, Iran University of Medical Sciences, Tehran, Iran.
Iran J Kidney Dis. 2021 Jan;15(1):31-37.
Dysregulated vitamin D metabolism is one of the most important issues in chronic kidney disease- mineral and bone disorder (CKD-MBD). Patients with end-stage kidney disease (ESKD) receive large amounts of calcitriol, i.e., 1,25 -dihydroxy vitamin D [1-25(OH)2D], for suppression of parathyroid hormone (PTH). The aim of this study was to evaluate the 1-25(OH)2D status in maintenance hemodialysis patients and its correlation with 25(OH) D level and calcitriol consumption and to determine whether the usual practice of administrating large amounts of calcitriol for suppression of PTH may lead to toxic serum levels.
One hundred and fifty-six maintenance hemodialysis patients were enrolled. Demographic data, comorbid conditions and history of medication use (cumulative and current doses) were retrieved from Hemodialysis Data Processor Software previously designed for our center. Predialysis serum samples were measured for serum levels of 25(OH)D and 1-25(OH)2D accompanying by markers of mineral bone metabolism and inflammation.
Of 156 patients, 66% were male and the mean age was 56.5 ± 16.3 years. There was no significant correlation between serum level of 25(OH)D and 1,25(OH)2D (r = 0.12, P > .05). Only current ingestion of vitamin D was correlated with both 25(OH) D (r = 0.324, P < .001) and 1,25(OH)2D serum levels (r = 0.334, P < .001). There was no significant relationship between current or cumulative calcitriol consumption and 1,25(OH)2D serum level. 1,25(OH)2D/25(OH)D ratio which, represents the degree of vitamin D hydroxylation efficiency was 0.9 pg/ng (expected value in no CKD > 2.2 pg/ng).
Calcitriol consumption was not correlated with increased serum 1,25(OH)2D level and the practice of hyperparathyroidism treatment with calcitriol may be safely continued, though we are not yet aware of the 1,25(OH)2D status at the cellular levels.
维生素D代谢失调是慢性肾脏病 - 矿物质和骨异常（CKD - MBD）中最重要的问题之一。终末期肾病（ESKD）患者会接受大量的骨化三醇，即1,25 - 二羟基维生素D [1,25(OH)₂D]，以抑制甲状旁腺激素（PTH）。本研究的目的是评估维持性血液透析患者的1,25(OH)₂D状态及其与25(OH)D水平和骨化三醇消耗量的相关性，并确定为抑制PTH而大量使用骨化三醇的常规做法是否会导致血清中毒水平。
纳入156例维持性血液透析患者。从先前为我们中心设计的血液透析数据处理软件中获取人口统计学数据、合并症情况和用药史（累积剂量和当前剂量）。透析前采集血清样本，检测血清25(OH)D和1,25(OH)₂D水平以及矿物质骨代谢和炎症标志物。
156例患者中，66%为男性，平均年龄为56.5±16.3岁。血清25(OH)D水平与1,25(OH)₂D水平之间无显著相关性（r = 0.12，P > 0.05）。仅当前维生素D摄入量与25(OH)D（r = 0.324，P < 0.001）和1,25(OH)₂D血清水平（r = 0.334，P < 0.001）均相关。当前或累积骨化三醇消耗量与1,25(OH)₂D血清水平之间无显著关系。代表维生素D羟化效率程度的1,25(OH)₂D/25(OH)D比值为0.9 pg/ng（无CKD时的预期值> 2.2 pg/ng）。
骨化三醇消耗量与血清1,25(OH)₂D水平升高无关，尽管我们尚不清楚细胞水平的1,25(OH)₂D状态，但用骨化三醇治疗甲状旁腺功能亢进的做法仍可安全继续。
