Cold Agglutinins Test

Test Overview

A cold agglutinins blood test is done to check for conditions that cause the body to make certain types of antibodies called cold agglutinins. Cold agglutinins are normally made by the immune system in response to infection. They cause red blood cells to clump together (agglutinate) at low temperatures.

Healthy people generally have low levels of cold agglutinins in their blood. But lymphoma or some infections, such as mycoplasma pneumonia, can cause the level of cold agglutinins to rise.

Higher-than-normal levels of cold agglutinins generally do not cause serious problems. Sometimes, high levels of cold agglutinins can cause blood to clump in blood vessels under the skin when the skin is exposed to the cold. This causes pale or bluish skin and numbness in the hands and feet. The symptoms go away when the skin warms up.

Sometimes high levels of cold agglutinins can destroy red blood cells throughout the body. This condition is called autoimmune hemolytic anemia.