Laboratory Test Information Guide

Details for Cryofibrinogen

Test Name: Cryofibrinogen
Alternate Name(s):  
Laboratory: Clinical Immunology
Specimen Type: 4 x 2.7 mL Light Blue (Sodium Citrate) Vacutainer tubes and 2 x 6 mL Red top Vacutainer tubes
Collection Information: The cryofibrinogen request includes cryoglobulin testing so additional blood tubes other than those stated are not required.

If possible, patient should be fasting.

Caution: Specimen is not acceptable when drawn on a patient receiving heparin or any other anti-coagulant.

Immediately after the blood draw, label the red top tubes and place in a thermos with warm (not hot) water. Water should be 37°C. Send to the laboratory specimen receiving area.

Do not leave the specimens at room temperature or refrigerate.

Transport the samples as soon as possible.
Test Schedule: Daily
Turnaround time from when specimen
is received in testing laboratory:
Final reports for Negatives: 7 days
Final reports for Positives: 10 days
Reference Range: Negative.
Effective Date: 2010-01-11
Revised Date: 2013-09-26
Critical Value:  
Interpretive Comments: Cryofibrinogen refers to cold-precipitable complexes of fibrin, fibrinogen and fibronectin. These may occur:

(i) when blood drawing is slow allowing thrombin generation ex vivo,
(ii) in any condition in which increased levels of fibrin occur
(iii) in certain dysfibrinogenemias.

Cryoglobulins may be found in serum and plasma but cryofibrinogen is only found in plasma. A positive cryofibrinogen is validated by a negative serum cryoglobulin.

A 2-day preliminary result for cryoglobulin and cryofibrinogen will be reported and available on Powerchart. The crits for positive cryoglobulin and cryofibrinogen are reported at the completion of the test.
The characterization is performed on the positive cryoglobulin only, not on the corresponding cryofibrinogen.
Special Processing: The specimen tubes must remain at 37°C until the plasma and serum have been separated.
Comments: If the cryoglobulin/cryofibrinogen develops as a gel rather than flocculation, the crit may be technically impossible to perform.
Method of Analysis: Manual
Critical Information Required: Is patient on anticoagulant therapy?
Storage & Shipment: The specimen blood tubes must remain at 37°C until the plasma and serum have been separated. After separation, the specimen can be stored or shipped at ambient temperature or refrigerated.
System Codes: 
Referred To:  

Questions? Comments? Contact Laura Gopaul