Parathyroid Hormone (PTH) Plus Calcium
Also known as: PTH Intact
Use
This test is used for differential diagnosis of hypercalcemia. PTH is an 84-amino acid peptide hormone that is responsible for the regulation of serum calcium levels within a narrow range.
Special Instructions
This test may exhibit interference if the sample is collected from a person consuming a supplement with a high dose of biotin (also known as vitamin B7 or coenzyme R). It is recommended to ask patients about biotin supplementation and advise them to stop taking it at least 72 hours before sample collection.
Limitations
Biologically inactive PTH fragments have interfered with the use of C-terminal or midmolecule assays for evaluating parathyroid function in patients with impaired renal function. The intact PTH assay overcomes these limitations, offering a more accurate assessment in patients with renal issues. Special consideration is needed for individuals consuming biotin supplementation due to potential assay interference.
Methodology
Immunoassay (ECLIA)
Biomarkers
LOINC Codes
- 24346-9
- 17861-6
- 2731-8
- 8251-1
Result Turnaround Time
1 day
Related Documents
For more information, please review the documents below
Specimen
Plasma
Volume
1.5 mL
Minimum Volume
0.7 mL
Container
Lavender-top (EDTA) tube
Collection Instructions
Transfer separated plasma to a plastic transport tube clearly labeled as EDTA plasma and maintain refrigerated temperature.
Patient Preparation
Patients should stop biotin intake at least 72 hours prior to collection.
Storage Instructions
Plasma should be kept refrigerated.
Causes for Rejection
Whole blood; plasma other than EDTA; hemolysis
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | 2 days |
| Refrigerated | 3 days |
| Frozen | 6 months |
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