Taniguchi Masatomo, Tanaka Motoko, Hamano Takayuki, Nakanishi Shohei, Fujii Hideki, Kato Hitoshi, Koiwa Fumihiko, Ando Ryoichi, Kimata Naoki, Akiba Takashi, Kono Takashi, Yokoyama Keitaro, Shigematsu Takashi, Kakuta Takatoshi, Kazama Junichiro James, Tominaga Yoshihiro, Fukagawa Masafumi
Department of Medicine and Clinical Science, Graduate School of Medical Sciences, Kyushu University, Higashi-ku, Fukuoka, Japan.
Ther Apher Dial. 2011 Jun;15 Suppl 1:42-9. doi: 10.1111/j.1744-9987.2011.00926.x.
The standard measurement of parathyroid hormone (PTH) is the intact PTH (iPTH) assay, which is used for approximately 90% of Japanese dialysis patients. The iPTH assay reacts not only with 1-84 PTH, but also with large truncated fragments of non-1-84 PTH, including 7-84 PTH. On the other hand, the whole PTH assay is specific for 1-84 PTH. The aim of the current study was to define the validity of both whole and intact PTH assays. A total of 738 hemodialysis patients were enrolled from twelve dialysis services. The serum PTH level was evaluated by both intact and whole PTH assays simultaneously. Non-1-84 PTH was determined by subtracting the whole PTH value from that of the intact PTH assay. The median level of whole PTH was 121 pg/mL, and that of iPTH was 210 pg/mL. The whole PTH assay had a very high correlation with the iPTH assay (r = 0.870, P < 0.001). For 43 out of 738 patients (5.8%) the value for intact PTH-whole PTH was <0. Both assays significantly correlated with non-1-84 PTH (P < 0.001), while the iPTH assay, particularly, had a very high correlation with non-1-84 PTH (r = 0.791). As a whole, 18% of the total population was misclassified into a different Japanese guideline category. Stratified by Japanese guideline classifications, 28% of patients within an iPTH target range were misclassified. Using Bland-Altman plot analysis, as the serum PTH level increased, there was a large difference between two assays. Both PTH assays correlate strongly, although the whole PTH assay may be more useful for precise evaluation of PTH function than the iPTH assay.
甲状旁腺激素（PTH）的标准检测方法是完整PTH（iPTH）检测，约90%的日本透析患者使用该方法。iPTH检测不仅能检测1-84 PTH，还能检测非1-84 PTH的大片段截短产物，包括7-84 PTH。另一方面，全段PTH检测仅针对1-84 PTH。本研究的目的是确定全段和完整PTH检测的有效性。我们从12个透析中心招募了738例血液透析患者。同时采用完整PTH检测和全段PTH检测评估血清PTH水平。非1-84 PTH通过完整PTH检测值减去全段PTH检测值来确定。全段PTH的中位数水平为121 pg/mL，iPTH为210 pg/mL。全段PTH检测与iPTH检测具有高度相关性（r = 0.870，P < 0.001）。738例患者中有43例（5.8%）的完整PTH-全段PTH值<0。两种检测方法均与非1-84 PTH显著相关（P < 0.001），尤其是iPTH检测与非1-84 PTH具有高度相关性（r = 0.791）。总体而言，18%的患者被错误分类到不同的日本指南类别。按日本指南分类进行分层分析，处于iPTH目标范围内的患者中有28%被错误分类。使用Bland-Altman图分析发现，随着血清PTH水平升高，两种检测方法之间存在较大差异。尽管全段PTH检测在精确评估PTH功能方面可能比iPTH检测更有用，但两种PTH检测方法的相关性都很强。
