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. See a picture
of the immune system
.
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 skin and numbness in the hands
and feet. The symptoms go away when the skin warms up. In some cases, the
clumped blood cells can stop the flow of blood to the tips of the fingers,
toes, ears, or nose. This is like frostbite and can cause tissue damage. In
rare cases, it can cause
gangrene.
Sometimes high levels of cold
agglutinins can destroy red blood cells throughout the body. This condition is
called autoimmune
hemolytic anemia.