Test Code PTHI 
Methodology Electrochemiluminescence Immunoassay 
Description Useful for distinguishing normal individuals from patients with primary hyperparathyroidism, hypoparathyroidism, and patients with hypercalcemia of malignancy.

No sample should be collected on patients receiving therapy with high biotin doses(i.e. biotin therapy for Multiple Sclerosis or oncology patients; skin, hair and nail supplements, or multivitamins containing > 5 mg/day) until at least 12 hours after the last biotin administration. If unsure, or if the clinical picture does not fit the results please contact the laboratory . We have methods to check for biotin interference as well as for any other interferences and for the accuracy of the results.

Biotin interference would falsely decrease the result of this assay. 

Specimen Draw blood in either a plain, red-top tube or serum gel tube. Spin down and send 2.0 mL (minimum 1.0 mL) of serum refrigerated in a plastic vial. Please freeze specimen if the interval between specimen collection and testing will be greater than 48 hours. 
Reference Values 15 - 65 pg/mL

Parathyroid hormone (PTH) values should be interpreted in conjunction with a serum calcium value. Since PTH is now only orderable as an individual test, a separate calcium order or value is required. 

Analytic Time 1 Day 
Day(s) Test Set Up Monday through Sunday 
CPT Code(s) 83970  Parathyroid hormone