Protein S, Functional

Label Mnemonic:	PROTSF
Epic code:	LAB9054
Downtime form:	A-1a Doctor/Provider Orders - Pathology Core and Specialty Care Nursery

Commercial Mailout Laboratory
6240-8 RCP
356-8593

Specimen(s):

Plasma

Collection Medium:

Light Blue top tube 2.7 mL (Na Citrate)

Minimum:

Preferred Minimum: 1.5 mL platelet-poor plasma in a Light Blue top tube.
Absolute Minimum: 1 mL platelet-poor plasma in a Light Blue top tube.

Rejection Criteria:

Serum. EDTA plasma, clotted or hemolyzed specimens.

Delivery Instructions:

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

Turn Around Time:

1-2 days upon receipt at reference laboratory.

Reference Range:

Male
1-89 days: 15-55%
90-179 days: 35-92% 
180-364 days: 45-115% 
1-5 years: 62-120%
6 years:  62-130%
7-9 years: 66-140%
10-11 years: 65-139%
12-13 years: 72-139%
14-15 years: 68-145%
16-17 years: 77-167%
18 years and older: 66-143%

Female
1-89 days: 15-55%
90-179 days: 35-92% 
180-364 days: 45-115% 
1-5 years: 62-120%
6 years:  62-130%
7-9 years: 62-151%
10-11 years: 65-142%
12-13 years: 70-140%
14-15 years: 55-145%
16-17 years: 51-147%
18 years and older: 57-131%

Interpretive Data:

Patients on warfarin may have decreased functional protein S values. Patients should be off warfarin therapy for two weeks for accurate measurement of functional protein S. Artificially increased functional protein S values may be due to heparin therapy or the presence of direct thrombin inhibitors or factor Xa inhibitors.

Comments:

This test is acceptable for detecting protein S deficiency. Do not order if the individual has been on warfarin therapy in the previous 2-4 weeks.

Methodology:

Electromagnetic Mechanical Clot Detection

CPT Code:

85306