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If you have additional questions regarding this test, please call: 415-353-1667
|Approval req'd?||No, however antigenic fibrinogen will only be performed if the functional fibrinogen is low.|
|Utilization Guidelines||Should only be ordered in patients with low levels of fibrinogen by functional assay.|
|Patient Preparation||Overnight fasting is required|
|Collection Instructions||1. Check the expiration date on the label of the blue top vacutainer before drawing the patient.
2. For blood collection in a sodium citrate blue top, the tube must be filled to above the Minimum Fill Indicator on the tube. It is crucial to wait and allow the tube to stop filling before removing it from the needle.
3. With use of a butterfly needle, draw about 1 cc using a separate blue top to remove air from tubing, discard the first tube and then draw a second blue top tube filled to the full extent of the vacuum.
4. Tubes should not be filled past the Maximum Fill dashed line by either using a syringe or removing the tube cap.
|Container type||Blue top filled to full extent of vacuum|
|Amount to Collect||2.7 mL blood|
|Sample type||Citrated plasma|
|Preferred volume||1 mL plasma|
|Min. Volume||0.5 mL plasma (1.0 mL for LabCorp)|
|UCSF Rejection Criteria||Samples collected in outdated blue top vacutainer. Over-filled or under-filled tubes may be rejected Hemolyzed sample.|
|Processing notes||Central Processing: Deliver whole blood sample to Hematology Lab ASAP.
Hematology: Freeze plasma at -20C.
If approved, ship frozen to Quest Nichols, test code #37801X. For Brown & Toland patient, order BTMOLT. Ship frozen to LabCorp, test # 117052
|Ref Lab Rejection Criteria||Sample received unfrozen|
|Normal range||180-350 mg/dL|
|Synonyms||Factor I; Fibrinogen antigen; Immunologic fibrinogen; Quantitative fibrinogen|
|Stability||Refrigerated 3 days, frozen at -20C 3 months.|
|Turn around times||Test is run Tuesday and Friday. Turnaround time: 7-10 days|
|Additional information||Use only to evaluate suspected abnormal fibrinogen.
If an abnormal fibrinogen is suspected, a functional fibrinogen and immunologic fibrinogen (fibrinogen, antigenic) must be run on the same sample. Therefore, if only a fibrinogen antigen is ordered, a functional fibrinogen will be automatically added and separately charged. The Fibrinogen antigen will only be performed if the Functional Fibrinogen is low. If the Functional Fibrinogen is normal, then the Fibrinogen antigen will be cancelled with the notation: Test Not Indicated. In the rare circumstance in which the functional fibrinogen is normal and an assessment for dysfibrinogenemia is nevertheless essential, please contact the hematology laboratory at 353-1747 to request that the immunologic fibrinogen be performed.
Rare individuals have a bleeding diathesis or a thrombotic tendency due to the presence of an abnormal fibrinogen (dysfibrinogenemia). This is most commonly hereditary, but dysfibrinogenemia with a bleeding tendency can be acquired in liver disease. Performing functional fibrinogen and immunologic fibrinogen on a plasma sample permits diagnosis of dysfibrinogenemia. Thrombin time and reptilase time are not necessary for diagnosis of dysfibrinogenemia.
|Last Updated||8/21/2014 12:31:33 PM|