PTH Intact, and Calcium

Message

Test performed at York Hospital Laboratory.

Test Code

PTHCA

Alias/See Also

PTH (Intact) and Calcium

CPT Codes
83970, 82310

Includes

Intact PTH
Calcium

Preferred Specimen

0.4 mL serum collected in a serum separator tube (SST)

Other Acceptable Specimens

0.4 mL plasma collected in a lithium heparin (green-top) tube 0.4 mL serum collected in a no additive (red-top) tube, transferred to a plastic screw-cap vial

Instructions

Specimen must be refrigerated or frozen within 1 hour of collection. All samples must be stored frozen at York Hospital prior to testing, then thawed when needed. Requests for add-on PTH testing are unacceptable. Samples collected at the offsite locations must be transferred to an aliquot tube and frozen prior to transporting to the main laboratory.

Transport Temperature

Frozen

Specimen Stability

Room temperature:1 hour
Refrigerated: 2 days
Frozen: 4 weeks

Reject Criteria (Eg, hemolysis? Lipemia? Thaw/Other?)

Hemolyzed specimens
Samples held at room temperature for longer than 1 hour

Methodology
Chemiluminescence Spectrophotometry

Setup Schedule

Monday, Wednesday, Friday

Report Available

3 Days

Reference Range

PTH, Intact

7.5 - 53.5 pg/mL

Age	Calcium (mg/dL)
<=3 Years	8.7 - 9.8
4-11 Years	8.8 - 10.1
12-13 Years	8.8 - 10.6
14-15 Years	9.2 - 10.7
16-19 Years	8.9 - 10.7
Adult	8.4 - 10.6

Critical Values

Calcium

< 6.0 or > 12.0 mg/dL

Clinical Significance

PTH measurement is an important aid in the diagnosis of disorders of calcium metabolism. PTH synthesis and secretion are triggered rapidly by low concentrations of ionized calcium. The biological activities of PTH are to increase absorption of dietary calcium, decrease renal clearance and mobilize skeletal calcium stores. Abnormally high ionized calcium concentrations suppress secretion of PTH. In conjunction with serum calcium levels, the PTH assay may be used as an aid in the differential diagnosis of hypercalcemia, hypocalcemia and parathyroid disorders. PTH determination is important in monitoring dialysis patients to manage renal osteodystrophy.

The CPT Codes provided in this document are based on AMA guidelines and are for informational purposes only. CPT coding is the sole responsibility of the billing party. Please direct any questions regarding coding to the payor being billed. Any Profile/panel component may be ordered separately. Reflex tests are performed at an additional charge.