PROTEIN S, FUNCTIONAL

Mnemonic

PROTS

Synonym

Protein S Activity

Specimen Collection Requirements

Patient Preparation

Patients on oral anticoagulants will have decreased functional protein C/S values. Patients should be off oral anticoagulant therapy for 2 weeks for accurate measurement of functional protein C/S levels.

Collect

Plasma, one 5 mL light blue (sodium citrate) top tube

Handling

See Coagulation Specimen Collection Guidelines. CRITICAL FROZEN. Separate specimens must be submitted when multiple tests are ordered.

Preferred Volume

2.0 mL

Minimum Volume

1.0 mL

Transport

Frozen

Rejection Criteria

Serum, nonfrozen or hemolyzed specimens

Stability

Ambient: 4 hours; Refrigerated: Unacceptable; Frozen at -20°C: 3 months, at -70°C: 6 months 

Testing Information

Note

Interfering factors: Artifactually decreased functional protein C/S values may be seen in patients with abnormally elevated levels of factor VIII. Artifactually elevated levels of functional protein C/S may be seen in patients receiving heparin therapy.

Performed

7 days/week

Reported

3-4 days

Method

Clotting

Referral Lab

ARUP (30114)

Reference Values

Reference Values

Interpretation provided.

CPT Codes

85306

Last Updated: Thursday, January 5, 2017 03:42:26 AM