Test Code 1136
Test Details
Parathyroid Hormone
PTH is a hormone secreted by the parathyroid glands that is important in bone remodeling. PTH functions as part of a feedback system that involves calcium, phosphorus (as phosphate), and vitamin D.
Methodology
Electrochemiluminescence Immunoassay (ECLIA)
Patient Preparation
None
Preferred Specimen
1.0 mL serum (0.5 mL minimum) collected in serum separator tube (SST/Tiger Top)
Transport Temperature
Refrigerated (ship on frozen cold packs)
Stability
Refrigerated: 2 days
Lab Values
Parathyroid Hormone
- Low: <15 pg/dL
- Normal: 15-65 pg/dL
- High: >65 pg/dL
Clinical Significance
Parathyroid Hormone
- Used to help diagnose the cause of a low or high calcium level and to help distinguish between parathyroid-related and non-parathyroid-related causes.
- A calcium test is almost always ordered along with PTH to determine the balance between calcium and PTH and the response of the parathyroid glands to changing levels of calcium.
- Most often ordered when calcium regulation is abnormal.
- High doses of biotin (> 5 mg/day) may interfere with assay results. Patient assumed to be refraining from biotin supplementation for at least 3 days prior to blood draw.
Treatment Options
Parathyroid Hormone
- Primary hyperparathyroidism – Surgery to remove adenoma or parathyroidectomy
- Secondary hyperparathyroidism – Treat underlying cause/condition most often kidney disease. In some cases, medication may be used to reduce PTH secretion and/or high calcium levels in blood.
- Patients with hypoparathyroidism are treated with calcium and vitamin D supplementation.
