AsseyMethod: Chemiluminescence
Abbrevation: PTH
Sector: Hormone 1
SampleType: S
S.Vol: -
Transport: 0.5 hrs. at 2-8c˚,at -20˚c
Storage: 2 hours at 25˚c,48 hours at 2-8˚c for longer time at -20˚c
Test Name: Parathyroid Hormone - Parathormone
Normal Range: 8.8-76
To determine the cause of calcium imbalance and to evaluate parathyroid gland function. PTH may be measured during surgery for hyperparathyroidism to help confirm removal of the parathyroid gland(s).
When calcium blood levels are higher or lower than normal, and when your doctor wants to determine how well your parathyroid glands are functioning.
A blood sample taken from a vein in your arm.
None
Parathyroid hormone (PTH) is required for calcium and phosphate balance. It is part of a ‘feedback loop’ that includes calcium, PTH, vitamin D, phosphate and magnesium. Conditions and diseases that disrupt this feedback loop can cause inappropriate elevations or decreases in calcium and PTH and lead to symptoms of hypercalcaemia (raised blood concentrations of calcium) or hypocalcaemia (low blood concentrations of calcium).
PTH is produced by four parathyroid glands that are located in the neck beside the thyroid gland. Normally, these glands secrete PTH into the bloodstream to regulate blood calcium concentration. Parathyroid hormone works in three ways to control blood calcium levels.. It takes calcium from bone, stimulates the activation of vitamin D in the kidney (which in turn increases the absorption of calcium from the intestines), and suppresses the excretion of calcium in the urine (while encouraging excretion of phosphate). As blood calcium concentrations rise, the concentration of PTH will normally decrease.
Parathyroid hormone is composed of 84 amino acids (sometimes called PTH (1-84)). Once it is released from the parathyroid gland into the blood stream, it has a very short life-span and levels fall by half in less than 5 minutes. The fall is caused primarily by the breakdown of PTH to smaller fragments.
How is the sample collected for testing?
A blood sample is obtained by inserting a needle into a vein in the arm.
Is any test preparation needed to ensure the quality of the sample?
No test preparation is needed.