Parathyroid glands (Latin: glandulae parathyreoideae) are four lentil-sized hormone-producing glands located at the back of the thyroid gland (Latin: glandula thyreoidea).

The parathyroid glands produce parathyroid hormone (abbreviated as PTH), which is a key hormone in regulating calcium balance. The most important disease of the parathyroid gland is hyperfunction, also called hyperparathyroidism. The causes of parathyroid hyperfunction can be varied. Diagnosis requires, among other things, certain laboratory tests, such as the determination of calcium, phosphate, and parathyroid hormone levels in the blood.¹

In primary and secondary hyperparathyroidism, the parathyroid glands produce too much parathyroid hormone. “Primary” means that the hyperparathyroidism is not caused by any other disease. A common cause is a benign tissue neoplasm (adenoma) of the parathyroid gland; malignant tumors are less common. “Secondary” means that hyperparathyroidism is caused by another disease, such as kidney disease. In this form, the parathyroid glands respond to an existing deficiency of calcium with increased production of parathyroid hormone. Both primary and secondary hyperparathyroidism can result in calcium loss from the bones, leading to bone pain, fractures, problems with the blood and heart vessels, kidney stones, mental illness, and coma.^1,2

The therapeutic goal is to normalize blood calcium, phosphate, and parathyroid hormone levels. This is achieved by treatment of the underlying disease, surgical removal of the parathyroid glands, vitamin D or calcium supplementation, a low-phosphate diet, or by taking drugs such as calcimimetics (these control the level of parathyroid hormone).^1,2

¹ Federal Ministry of Social Affairs, Health, Long-Term Care and Consumer Protection (BMSGPK) (ed.): https://www.gesundheit.gv.at/krankheiten/stoffwechsel/ueberfunktion-nebenschilddruesen (accessed: July 23, 2020).

² Package leaflet Cinglan®, Date of information: 08/2019.