Fukagawa M, Kitaoka M, Kurokawa K
First Department of Internal Medicine, University of Tokyo School of Medicine, Japan.
Nephrol Dial Transplant. 1996;11 Suppl 3:125-9. doi: 10.1093/ndt/11.supp3.125.
Calcitriol pulse therapy has markedly changed the management of secondary hyperparathyroidism in chronic dialysis patients. However, there are still many patients even resistant to this therapy. Our observation of parathyroid size by ultrasonography revealed that these patients usually have enlarged parathyroid glands larger than 0.5 cm3. Such large parathyroid glands are composed of nodular hyperplasia with monoclonal cell proliferation, whose calcitriol receptor density is lower than that of diffuse hyperplasia, thus more resistant to calcitriol. Based on such a pathophysiological model, we have shown that destruction of the largest parathyroid gland was sufficient to restore the responsiveness to calcitriol therapy in these refractory patients. By using colour Doppler ultrasonography, we could also optimize the site and volume of ethanol injection and could detect the recurrence of parathyroid cell growth easily, with lower risk of complications. This selective route of drug delivery to parathyroid glands can be also used for direct injections of calcitriol solution as we have reported. Thus, evaluation of parathyroid size by sensitive ultrasonography is an essential marker for the management of parathyroid hyperfunction in chronic dialysis patients. It is also suggested that ultrasonographic intervention of parathyroid hyperplasia may not only be a useful and safe adjunct to calcitriol pulse therapy, but may also serve as a new therapeutic modality for parathyroid diseases in future.
骨化三醇冲击疗法显著改变了慢性透析患者继发性甲状旁腺功能亢进的治疗方式。然而，仍有许多患者对此疗法耐药。我们通过超声对甲状旁腺大小进行观察发现，这些患者的甲状旁腺通常肿大，体积超过0.5立方厘米。如此大的甲状旁腺由结节性增生组成，伴有单克隆细胞增殖，其骨化三醇受体密度低于弥漫性增生，因此对骨化三醇更具耐药性。基于这样的病理生理模型，我们已表明，破坏最大的甲状旁腺足以恢复这些难治性患者对骨化三醇治疗的反应性。通过使用彩色多普勒超声，我们还可以优化乙醇注射的部位和体积，并能轻松检测甲状旁腺细胞生长的复发情况，并发症风险较低。正如我们所报道的，这种向甲状旁腺给药的选择性途径也可用于直接注射骨化三醇溶液。因此，通过敏感的超声评估甲状旁腺大小是慢性透析患者甲状旁腺功能亢进治疗的重要指标。还表明，甲状旁腺增生的超声干预不仅可能是骨化三醇冲击疗法有用且安全的辅助手段，而且未来可能成为甲状旁腺疾病的一种新治疗方式。
