Test Results For:
Parathyroid Hormone (PTH)
Test Overview
- Test Name
-
Parathyroid Hormone (PTH)
- Test Code
- PTH
Short Description
PTH
Test Name
Parathyroid Hormone (PTH)
Test Code
PTH
Category
Immunoassay
TAT
Main Lab:
6, 24
Hour(s), Day(s)
Family Site:
<8hrs, <6hrs, 1 Day
Specimen(s)
1 x Venous blood - 5 mL Tube - Lavender - EDTA Whole Blood , 1 x - 5 mL Tube - Lavender - EDTA Plasma
Specimen Type
EDTA Whole Blood
Specimen Format
Tube
Specimen Colour
Lavender
Specimen Volume
5 mL
Sampling Order
4
Origin
Venous blood
Collection Time after baseline
-
Transport Temperature
15-25°C
Accepted Other Specimens
Lithium Heparin Plasma
TAT
Main Lab:
6, 24
Hour(s), Day(s)
Family Site:
<8hrs, <6hrs, 1 Day
Test Stability
Room Temp:
8 Hour(s)
2–8°C:
2 Day(s)
Specimen Type
EDTA Plasma
Specimen Format
Tube
Specimen Colour
Lavender
Specimen Volume
5 mL
Sampling Order
4
Origin
-
Collection Time after baseline
-
Transport Temperature
15-25°C
Accepted Other Specimens
Lithium Heparin Plasma
TAT
Main Lab:
6, 24
Hour(s), Day(s)
Family Site:
<8hrs, <6hrs, 1 Day
Test Stability
Room Temp:
8 Hour(s)
2–8°C:
2 Day(s)
Methodology
-
Specimen Type
EDTA Whole Blood
Other Type of Specimen Accepted
Lithium Heparin Plasma
Delay before pre-treatment
8
Transport temperature
15-25°C
Test stability at room temperature
8 Hour(s)
Test stability at 2–8°C
2 Day(s)
Haemolysis interference
No
Clinical Interest
Parathyroid hormone (PTH) is produced by the parathyroid gland.
The main role of PTH is to regulate calcium levels in the blood through a combined effect on three main organs: the bones, the intestinal mucosa and the kidneys.
Its action on intestinal calcium is indirect and results from the renal production of the vitamin D metabolite active in the intestine, 1,25-dihydroxyvitamin D.
In the kidney, PTH stimulates calcium reabsorption and inhibits phosphate reabsorption in the renal tubules.
Finally, PTH promotes osteoclastic bone resorption and the release of calcium and phosphate from the bone.
In hypercalcaemia due to primary hyperparathyroidism or ectopic PTH secretion (pseudohypoparathyroidism), most patients have elevated PTH levels.
On the other hand, in the case of hypercalcaemia due to malignancy or other causes, the concentration of PTH in the circulation is generally low, below or close to the lower limit of the reference values.
Secondary hyperparathyroidism is a compensatory hyperfunction of the parathyroid glands caused by hypocalcaemia or peripheral resistance to PTH. It is generally caused by renal failure. Chronic overproduction of PTH in renal failure increases the risk of bone disease (renal osteodystrophy).
Periodic measurement of serum calcium, phosphorus and PTH levels is recommended in all patients with chronic renal disease.
Hypoparathyroidism is an uncommon congenital or acquired condition in which PTH secretion is deficient or absent.
In most cases, hypoparathyroidism follows parathyroidectomy or thyroidectomy. Pseudohypoparathyroidism is a rare condition.
Clinical Information Required
-
Patient Collection Note
-
LOINC Code
31-8, 2731-8
Outwork
No