Cryocrit, cryoprotein

This test is done to find out if you have abnormal proteins called cryoglobulins 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 (cryoglobulins) are dissolved in your blood at the normal body temperature. But when you are in a cold environment, they may thicken and clump together. This restricts the blood flow to your joints, muscles and organs. This can eventually lead to damage and inflammation of your blood vessels and tissues. 

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

You may need this test if your healthcare provider suspects that you have a problem with your blood proteins. Symptoms tend to happen 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.

Your healthcare provider 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 healthcare provider may also order tests to measure blood levels of other antibodies, including antinuclear antibodies, antibodies to DNA, and antibodies to phospholipids.

Test results may vary depending on your age, gender, health history, the method used for the test, and other things. Your test results may not mean you have a problem. Ask your healthcare provider what your test results mean for you. 

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 healthcare provider will do more tests to find out the cause.

The test is done with a blood sample. A needle is used to draw blood from a vein in your arm or hand. 

Having a blood test with a needle carries some risks. These include bleeding, infection, bruising, and feeling lightheaded. When the needle pricks your arm or hand, you may feel a slight sting or pain. Afterward, the site may be sore. 

Other factors aren't likely to affect your results.

You may need to not eat or drink anything but water for 8 hours before the test. Be sure your healthcare provider knows about all medicines, herbs, vitamins, and supplements you are taking. This includes medicines that don't need a prescription and any illicit drugs you may use.