Department of Endocrinology and Internal Medicine, Tage-Hansens Gade (THG), Aarhus University Hospital, Aarhus, Denmark.
J Bone Miner Res. 2018 Mar;33(3):467-477. doi: 10.1002/jbmr.3328. Epub 2017 Nov 30.
Nonsurgical hypoparathyroidism (Ns-HypoPT) and pseudohypoparathyroidism (PHP) are both rare diseases, characterized by hypocalcemia. In Ns-HypoPT, PTH levels are low, whereas patients with PHP often have very high levels due to receptor-insensitivity to PTH (PTH-resistance). Accordingly, we hypothesized that indices of bone turnover and bone mineralization/architecture are similar in Ns-HypoPT and PHP despite marked differences in PTH levels. We studied 62 patients with Ns-HypoPT and 31 with PHP as well as a group of age- and sex-matched healthy controls. We found a significantly higher areal BMD (aBMD) by DXA among patients with Ns-HypoPT, both compared with PHP and the background population. Compared with Ns-HypoPT, PHP patients had significantly lower total and trabecular volumetric BMD (vBMD) assessed by quantitative computed tomography (QCT) scans at the spine and hip. High-resolution peripheral quantitative computed tomography (HRpQCT) scans showed a lower trabecular area and vBMD as well as a lower trabecular number at the tibia in PHP compared to Ns-HypoPT and matched controls. In PHP, PTH levels correlated with levels of markers of bone formation (osteocalcin, bone-specific alkaline phosphatase, P1NP), and bone resorption (CTx). In adult males, levels of bone markers were significantly higher in PHP compared with Ns-HypoPT. Levels of procalcitonin and calcitonin were significantly higher in PHP compared with Ns-HypoPT. In conclusion, indices of bone turnover, density, and microarchitecture differ between patients with Ns-HypoPT and PHP. Our data suggest that patients with PHP do not have a complete skeletal resistance to PTH and that the effects of chronically high PTH levels in PHP are mostly confined to the trabecular tissue. © 2017 American Society for Bone and Mineral Research.
非手术性甲状旁腺功能减退症（Ns-HypoPT）和假性甲状旁腺功能减退症（PHP）都是罕见疾病，其特征为低钙血症。在 Ns-HypoPT 中，PTH 水平较低，而 PHP 患者由于对 PTH 的受体不敏感（PTH 抵抗），其 PTH 水平通常非常高。因此，我们假设尽管 PTH 水平存在明显差异，但 Ns-HypoPT 和 PHP 患者的骨转换和骨矿化/结构指数相似。我们研究了 62 名 Ns-HypoPT 患者和 31 名 PHP 患者以及一组年龄和性别匹配的健康对照者。我们发现 DXA 测定的 Ns-HypoPT 患者的面积骨密度（aBMD）显著高于 PHP 患者和背景人群。与 Ns-HypoPT 相比，PHP 患者的脊柱和髋部定量计算机断层扫描（QCT）评估的总骨密度（vBMD）和小梁骨密度（vBMD）明显更低。高分辨率外周定量计算机断层扫描（HRpQCT）显示 PHP 患者的胫骨小梁面积和 vBMD 以及小梁数量均低于 Ns-HypoPT 和匹配对照组。在 PHP 中，PTH 水平与骨形成标志物（骨钙素、骨特异性碱性磷酸酶、P1NP）和骨吸收标志物（CTX）的水平相关。在成年男性中，PHP 患者的骨标志物水平明显高于 Ns-HypoPT。与 Ns-HypoPT 相比，PHP 患者的降钙素原和降钙素水平明显更高。总之，Ns-HypoPT 和 PHP 患者的骨转换、密度和微观结构指数存在差异。我们的数据表明，PHP 患者的骨骼对 PTH 不完全抵抗，并且 PHP 中慢性高 PTH 水平的影响主要局限于小梁组织。
