Protein S Antigen, Free
Label Mnemonic: | PSAF |
Epic code: | LAB8982 |
Order form: | Laboratory Requisition |
Supply order: | Supply Order Form |
Billing: | Billing Policies |
CPT code: | 85306 |
Specimen(s):
Plasma
Collection Medium:
Light Blue top tube 2.7 mL (Na Citrate) |
Minimum:
Full draw, 2.7 mL light blue top tube
Rejection Criteria:
Short drawn tube, clot, traumatic tap (excessive hemolysis).
Testing
Schedule:
0800-1630 Monday, Wednesday and Friday. If you need results STAT, call Hematology resident (0800-1630, M-F) at 356-8628. All other times page the Pathology resident on-call at 3404.
Turn Around
Time:
1-3 days upon receipt in laboratory
Reference Range:
Females: 66-147%
Males: 73-139%
Males: 73-139%
Interpretive Data:
Patients on warfarin may have decreased free protein S antigen concentrations. Warfarin therapy should be discontinued for at least two weeks prior to protein S testing. Decreased concentrations of free protein S antigen are also associated with liver disease, vitamin K deficiency, acute thrombosis, and DIC. Pregnancy, estrogen therapy, nephrotic syndrome, and inflammatory syndromes increase C4b binding protein concentrations, thus decreasing free protein S levels.
Methodology:
Immunoturbidimetric assay
Sample
Processing:
Centrifuge within four hours of draw time.
Separate plasma into plastic container and cap (glass is not acceptable).
Centrifuge a second time to ensure platelet poor plasma and separate plasma into a new, labeled plastic tube, cap.
Separate plasma into plastic container and cap (glass is not acceptable).
Centrifuge a second time to ensure platelet poor plasma and separate plasma into a new, labeled plastic tube, cap.
Sample
Storage:
Freeze specimen immediately.
Transport
Instructions:
Place labeled specimen into zip-lock type biohazard bag; seal bag.
Place packing list into outside pocket of bag.
Place dry ice on top of specimen in Styrofoam container.
Place packing list into outside pocket of bag.
Place dry ice on top of specimen in Styrofoam container.
CPT Code:
85306