| Test Description |
|
Test Name
|
Factor XIII Activity (5M Urea) |
|
Synonym
|
Factor XIII; Factor XIII Assay |
|
Description
|
Factor XIII is a plasma proenzyme responsible for stabilization of the fibrin polymers by cross linking. Inheritance of Factor XIII deciciency is automsomal recessive. Patients with severe Factor XIII deficiencies have bleeding symptoms including poor and delayed wound healing, central nervous system hemorrhage, delayed bleeding and post surgical hemorrhage. The urea solubility assay is used as a screening test for severe Factor XIII deficiency. Levels >1-2% will give a normal result. This assay is used to diagnose acquired or hereditary Factor XIII deficiency. Reduced levels of Factor XIII are not associated with bleeding. |
|
Methodology
|
Urea Solubility |
|
Performed
|
Wednesday |
|
Turnaround Time
|
1-7 days |
|
Specimen Requirements
|
3 mL platelet-poor citrated plasma (light blue 3.2% sodium citrate tube). Freeze plasma within 4 hours of collection in 1 mL aliquots.
Transport frozen.
Minimum volume 2 mL.
Coagulation Drawing Instructions:
- When drawing coagulation tests, always draw a "pilot" tube (7-10 mL plain red top tube, completely filled). This removes tissue fluid contamination, discard pilot tube.
- Draw blood in a light blue (3.2% sodium citrate) top tube. Fill tubes as far as vacuum will fill and mix gently. Ratio of anticoagulant and blood must be maintained. Avoid slow flowing draws and traumatic venipunctures.
- Spin vacutainer – remove plasma avoiding platelet/buffy layer – spin plasma again – remove top portion of plasma and place 1 mL of PLATELET-POOR PLASMA in plastic tube. (Glass tube unacceptable)
- Double-centrifugation is critical for accurate results as platelet contamination may cause erroneous results.
- Plasma must be frozen within 4 hours of collection.
- CRITICAL WARNING: Specimen must remain frozen until testing. Submit separate aliquots when multiple tests are ordered on same patient specimen.
|
|
Rejection Criteria
|
Plasma hemolyzed, thawed or contaminated with heparin. |
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CPT Code(s)
|
85291 |
|
Reference Range
|
The laboratory will provide an interpretive report. |
|
Contact Information
|
Hemostasis Lab: 214-645-5067
Customer Service: 214-645-7057, Toll Free 877-887-8136 |
