ARUP's Laboratory Test Directory

0030114: Protein S, Functional

Test Mnemonic: PROT S F
Methodology: Clotting

Performed: Sun-Sat

Reported: 1-2 days

Specimen Required:  
Collect: One 5 mL lt. blue (sodium citrate).  Refer to the Hemostasis/Thrombosis Specimens section in the front of this User's Guide for specimen collection instructions.

Transport: 2 mL platelet-poor plasma, frozen. (Min: 1 mL) Submit specimen in an ARUP Standard Transport Tube.

Pediatric Collection/Transport: 1 mL platelet-poor plasma, frozen.

Remarks: CRITICAL FROZEN.  Separate specimens must be submitted when multiple tests are ordered.

Unacceptable Conditions: Serum.  Nonfrozen or hemolyzed specimens.

Stability: Ambient: 2 hours; Refrigerated: 4 hours; Frozen: 2 weeks

Reference Interval:
Male
1-89 days: 15-55%
90-179 days: 35-92%
180-364 days: 45-115%
1-6 years: 62-120%
7-9 years: 64-141%
10-11 years: 68-180%
12-13 years: 65-143%
14-15 years: 66-149%
16-17 years: 75-157%
18 years and older: 66-143%

Female
1-89 days: 15-55%
90-179 days: 35-92%
180-364 days: 45-115%
1-6 years: 62-120%
7-9 years: 58-154%
10-11 years: 68-140%
12-13 years: 60-150%
14-15 years: 53-147%
16-17 years: 51-150%
18 years and older: 57-131%

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

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.



CPT Code(s):
85306