Test Code LAB4071 CRYOGLOBULIN
Specimen Type
10 mL Glass Red Top tube
Collection Instructions
Draw 3 × 10ml glass red top tubes. Keep Warm using activated heat pack and transport directly to the lab, place in 37°C degree heat block or submerged upright in 37°C waterbath as soon as possible to fully clot.
Specimens MUST be kept at 37°C during collection, tansporation and processing.
Specimen Volume
30 mL
Minimum Volume
5 mL
Turnaround Time
7 days
Test Schedule
Daily
Sample Stability
Refrigerated: 7 Days
Specimen Processing
- Place 3 x10 mL red top serum tubes upright in the 37°C heat block or submerged upright in 37°C waterbath for at least 1 hour to allow the tubes tob fully clot.
- Place 3 conical centrifuge tubes in the heat block to warm to 37°C before use.
Note: We do not advise using disposable conical centrifuge tubes (the ones commonly used in urinalysis or body fluids) as they crack easily and often do not withstand the faster centrifugation process.
- After 1 hour, and without spinning the tubes, aliquot the unclotted supernatant from all serum tubes into one of the pre-warmed conical centrifuge tube.
Important: For the next step DO NOT use refrigerated centrifuge.
- Centrifuge the conical centrifuge tube for 5 minutes at 3000 rpm
- When centrifugation is complete, remove the other 2 empty conical tubes from water bath
- Place exactly 5 mL of serum in one of the empty, pre-warmed conical centrifuge tube
- Place the remaining serum in the second empty, pre-warmed conical centrifuge tube
- Label and cap the tubes and store at 2-8°C.
Method
Precipitation
Reference Ranges
Cryoglobulin Negative
Cryocrit < 0.1%
Test Components
Cryoglobulin.
Cryocrit.
CPT Codes
82595
Result Interpretation
Results will be preliminarily determined as negative or positive on a daily basis. Results from 24 hours, 48 hours, 72 hours and 7 days will be reported in the LIS on day 7. Any positive results will require a crycrit calculation on the conical tube with 5mL and re-warming of the 2nd conical tube to verify if the specimen is a true postive.
Limitations
- Tests is not useful for general screening of a population without a clinical suspicion of cryoglobulinemia.
- Temperature control before and after serum separation is very important. Failure to keep specimen at 37°C during the processing of the sample can lead to false-negative results.
- Falsely low cryocrits will occur if the precipitated serum is not kept cold while determining the cryocrit.