Synonyms: PTH
Related tests: osteocalcin, Vitamin D, Calcium
Clinical significance
Parathyroid hormone is a polypeptide hormone produced by the parathyroid glands, four small glands around the thyroid. The role of parathyroid hormone is to maintain the balance of calcium and phosphate in the plasma; in particular, PTH stimulates bone resorption, increases phosphate excretion and calcium reabsorption in the kidneys, and increases calcium absorption from the gut by stimulating the production of vitamin D 1,25(OH) in the kidneys. PTH secretion is regulated by the plasma calcium concentration through feedback.
Clinical indications
Suspected hyper- or hypoparathyroidism
Sample type
The patient must have a blood sample taken.
Preparation
You must fast for at least 8 hours; a small amount of water is allowed. You must have been standing or sitting upright for at least 30 minutes.