Protein S (Activity)

Message

Performed in the Hematology Laboratory x5475, 76. Sample MUST be drawn to minimum fill line on tube.
This test should not be performed on pregnant females.

Test Code

PSFN

CPT Codes
85306

Preferred Specimen

plasma

Minimum Volume

2.7 mL. Sample MUST be drawn to minimum fill line on tube or the sample will be rejected as QNS.

Instructions

If drawn with other coagulation assays: for up to 3 tests draw 1, 2.7mL sodium citrate tubes. For 4 or more coagulation tests, draw 2, 2.7 mL sodium citrate tubes.

Transport Container

Light Blue Top (Sodium Citrate), 2.7 mL draw tubes

Transport Temperature

Room temperature

Specimen Stability

Refrigerator Stability: 4 hours
Plasma is stable for 6 months frozen at -70 degrees C.

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

Gross hemolysis, QNS, Clotted, Lipemic

Methodology

Optical clot detection

Setup Schedule

Performed 1x/week, weekdays between 8-4pm

Limitations

Test not performed when patient is taking Coumadin; must be off for at least 10 days before testing. DTI's (Argatroban) and other oral Xa inhibitors may show falsely normal or increased values; report Free Protein S value instead. Pregnancy may lower Protein S levels.

Reference Range

0 -	5 days	22%	78%
		22%	78%
5 days -	1 month	33%	93%
		33%	93%
1 month -	3 months	54%	118%
		54%	118%
3 months -	6 months	55%	119%
		55%	119%
6 months -	150 years	70%	140%
		70%	140%
**Female Ranges are in BLUE

Results below reference range will reflex an order for the Free Protein S Antigen Assay.

Clinical Significance

A test for congenital or acquired hypercoagulability (pulmonary embolism, stroke, DVT). Decreased levels seen in liver disease, during pregnancy, and when taking Coumadin.

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.