Does this test have other names?

Cryocrit, cryoprotein

What is this test?

This test is done to find out if you have abnormal proteins in your blood.

Blood proteins include normal immunoglobulins, or antibodies, like IgG and IgM. But they can also include antibodies linked to autoimmune diseases. These abnormal blood proteins are dissolved in your blood at body temperature, but they change into solid clumps when the blood is cooled.

These abnormal proteins are called cryoglobulins. High levels of cryoglobulins may be a sign that your body is making abnormal proteins. This condition is seen with a number of disorders and conditions, such as Raynaud's syndrome, lupus, rheumatoid arthritis, Sjogren's syndrome, leukemia, and lymphoma.

Why do I need this test?

You may need this test if your doctor suspects that you have a problem with your blood proteins. Symptoms tend to occur in cold weather and include:

  • Skin blueness

  • Numbness or tingling

  • Coldness in the fingers

In more severe cases, it can also cause joint pain or tissue damage.

What other tests might I have along with this test?

Your doctor may also order a joint fluid analysis if he or she suspects that you have a systemic inflammatory disease, such as lupus or rheumatoid arthritis. Your doctor may also order tests to measure blood levels of other antibodies, including antinuclear antibodies, antibodies to DNA, and antibodies to phospholipids.

What do my test results mean?

Many things may affect your lab test results. These include the method each lab uses to do the test. Even if your test results are different from the normal value, you may not have a problem. To learn what the results mean for you, talk with your health care provider.

A normal test is negative for cryoglobulins. This means the antibodies in your blood stay dissolved even when the blood is chilled.

If you test positive for cryoglobulins, it means these proteins became visibly sludge-like when your blood sample was refrigerated. If your cryoglobulin test is positive, your health care provider will do more tests to find out the cause.

How is this test done?

The test requires a blood sample, which is drawn through a needle from a vein in your arm.

Does this test pose any risks?

Taking a blood sample with a needle carries risks that include bleeding, infection, bruising, or feeling dizzy. When the needle pricks your arm, you may feel a slight stinging sensation or pain. Afterward, the site may be slightly sore.

What might affect my test results?

Other factors aren't likely to affect your results.

How do I get ready for this test?

You may need to not eat or drink anything but water for eight hours before the test.