1. Hạ can xi máu: Symptoms of hypocalcemia include neuromuscular irritability (including tetany as manifested by Chvostek’s sign or Trousseau’s sign, bronchospasm), electrocardiographic changes, and seizures.

1. Dấu hiệu Chvostek and Trousseau: Xem
2. Dấu hiệu bàn tay đỡ đẻ (carpopedal spasm : Xem
3. ...

2. Tăng canxi máu : Primary hyperparathyroidism is caused by excess PTH secretion. PTH-secreting adenomas are asymptomatic. It occurs more frequently in women. Extreme osteoclastic activity is observed in the bones. Osteoblastic activity also increases in the bones. Calcium ion concentration is elevated in the extracellular fluid, while concentration of phosphate ions is usually depressed. Serum alkaline phosphate levels are usually high.

Radiographs of the bones show extensive decalcification. Other observations include:

1. Multiple fractures
2. Osteitis fibrosa cystica-bones are eaten away in severe hyperparathyroidism i.e. slow, extensive decalcification with ‘punched out cystic areas’
3. Parathyroid poisoning and metastatic calcification
4. Kidney stones- due to crystals of calcium phosphate