Coagulation
Coagulation laboratory tests
Cryoglobulin / cryofibrinogen assays
Author: Jeremy C. Parsons, M.D.
Last author update: 1 June 2012
Last staff update: 15 September 2020
Copyright: 2002-2023, PathologyOutlines.com, Inc.
PubMed Search: Cryoglobulin assays OR Cryofibrinogen assays
Table of Contents
Definition / generalCite this page: Parsons JC. Cryoglobulin / cryofibrinogen assays. PathologyOutlines.com website. https://www.pathologyoutlines.com/topic/coagulationcryofibrinogen.html. Accessed June 3rd, 2023.
Definition / general
- Either asymptomatic or causes cutaneous symptoms at cold - exposed areas
- Cryofibrinogen consists of fibrinogen and other substances that precipitate at cold temperatures (cryoglobulins are immunoglobulins that precipitate at cold temperatures)
- Either primary, or associated with malignancy, infection (especially hepatitis C), inflammatory conditions, diabetes, pregnancy, oral contraceptives
- May exhibit leukocytoclastic vasculitis in skin biopsies
- Specimen:
- Two sodium citrate or EDTA tubes plus one red top tube for cryoglobulin
- Place immediately in warm water (or use warmer for heal sticks or other warming method) and transport to laboratory within 2 hours
- Dont use heparin - containing specimens (heparin precipitates fibrinogen in this assay)
- Indication:
- For patients with unexplained cutaneous ulcers or ischemia on cold - exposed areas
- Procedure:
- Centrifuge at 37C, refrigerate plasma, centrifuge at 4C
- Each mm of visible precipitate represents 1% of cryofibrinogen
- Cyrocrit is %volume of precipitate compared to total plasma
- Also perform cryoglobulin test to ensure that plasma precipitate is not a cryoglobulin
- If the cryoglobulin test is positive, serum protein electorpheresis with immune fixation should be run to determine what type of cryoglobulin is present
