Does this test have other names?

Cryofibrinogenemia, CF

What is this test?

This test looks for an abnormal protein called cryofibrinogen in your blood plasma.

People who have this abnormal protein may get a disorder called cryofibrinogenemia. The disorder rarely causes symptoms. But if it's not treated, it can become life-threatening and lead to stroke, heart attack, gangrene, or other health emergencies.

Why do I need this test?

You may need this test to find out whether you have cryofibrinogenemia. Or your healthcare provider may order it to see how well your treatment for cryofibrinogenemia is working. When this disorder causes signs and symptoms, they may include:

• Sensitivity to cold, including itching, redness, swelling, or hives

• Red or purple marks on the skin, a condition called purpura

• Skin sores (lesions and ulcers)

• Stroke

• Heart attack

• Poor circulation

• A blood clot in the lungs (pulmonary embolism)

• Swelling caused by a blood clot, usually in the legs (phlebitis)

• Joint pain

• Inflammation of your kidneys (glomerulonephritis)

There are 2 types of cryofibrinogenemia. Primary or essential cryofibrinogenemia happens without any other health conditions. It's rare. Secondary cryofibrinogenemia happens with a range of other disorders. These include:

• Certain cancers, such as non-Hodgkin lymphoma and colorectal cancer

• Infections, such as sepsis, tuberculosis, streptococcus, herpes, and hepatitis C

• Connective tissue disorders, such as lupus or Crohn's disease

• Vasculitis, a disorder caused by inflammation of blood vessels 

What other tests might I have along with this test?

Your healthcare provider will order other tests if your cryofibrinogen test shows that you have cryofibrinogenemia. To diagnose primary cryofibrinogenemia, your provider may order an angiogram to look for blocked arteries. Or they may order a biopsy of affected tissue.

Additional tests depend on your symptoms and history, but may include screenings for cancer, infection, and inflammatory diseases.  

What do my test results mean?

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

Your test results show whether and how much cryofibrinogen is in your blood plasma. Healthy people can have a small amount of this protein in their blood, so a positive result alone doesn't necessarily mean that you have a problem.    

How is this test done?

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

Does this test pose any risks?

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. 

What might affect my test results?

If you are taking a blood thinner containing heparin, you may get a false-positive test result. 

How do I get ready for this test?

You don't need to prepare for this 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.