| [ Summary ] |
The parathyroid gland progresses to the hyperplasia under azotemic conditions. Patients with nodular hyperplasia, which is characterized by blunted sensitivity to vitamin D and calcium, become resistant to medical therapy. Histologically most glands exceeding 0.5 g in weight are nodular hyperplasia. To evaluate the stage of hyperplasia, ultrasonographic color flow mapping is useful. Patients with undetectable parathyroid or with only small glands without in-gland color signals, usually respond to medical therapy. On the other hand, patients with in-gland color signals strongly suggest nodular hyperplasia. Patients whom we are suspicious of harboring nodular hyperplasia are usually resistant to medical treatment and interventional therapy should be considered. If this is not done Ca X P products rise with vitamin D therapy, leading to ectopic calcification. |