Cold Agglutinins Test

Why It Is Done

The cold agglutinins test may be done to:

• See whether high cold agglutinin levels are causing autoimmune hemolytic anemia.
• Find pneumonia caused by mycoplasma. Over half of people with pneumonia caused by mycoplasma develop an increase in cold agglutinin levels in their blood within a week of being infected. Newer tests for mycoplasma pneumonia have replaced the cold agglutinins blood test.

How To Prepare

In general, there's nothing you have to do before this test, unless your doctor tells you to.

How It Is Done

A health professional uses a needle to take a blood sample, usually from the arm.

How It Feels

When a blood sample is taken, you may feel nothing at all from the needle. Or you might feel a quick sting or pinch.

Risks

There is very little chance of having a problem from this test. When a blood sample is taken, a small bruise may form at the site.

Results

Normal

Each lab has a different range for what's normal. Your lab report should show the range that your lab uses for each test. The normal range is just a guide. Your doctor will also look at your results based on your age, health, and other factors. A value that isn't in the normal range may still be normal for you.

High values

• High titers of cold agglutinins may be caused by infections, such as pneumonia caused by mycoplasma, mononucleosis, hepatitis C, or other viral infections.
• High titers of cold agglutinins can cause symptoms when a person is exposed to cold temperatures. These symptoms can include numbness, burning, pain, or pale skin of the fingertips, toes, ears, or nose. Very high titers can mean you have a higher chance of developing blood clots (thromboses) when exposed to cold temperatures.