Cold agglutinins are substances produced by the body's immune system as a response to infection. They cause the red blood cells to agglutinate or form clumps at cooler temperatures. Individuals who are in good health usually have low quantities of cold agglutinins in the blood. Conditions such as lymphoma or mycoplasma pneumonia can result in a rise of cold agglutinin levels. High levels of these substances are usually not a cause for concern. They cause the blood to agglutinate beneath the skin when exposed to cold temperatures. This results in numbness in the limbs. Once the body is exposed to warmer temperatures, the symptoms are alleviated. In certain cases, this condition can obstruct the blood flow to the nose, ears and toes. This may cause tissue damage and in rare instances, gangrene may also develop. A cold agglutinins blood test is performed to detect conditions in the body that cause it to produce cold agglutinins.
A cold agglutinin test is performed in order to:
A sample of blood is drawn from a vein in the arm of the individual. No special preparations are required before taking the test.
The test results are reported in terms of titers. A titer refers to the extent to which a sample of blood can be diluted until the cold agglutinins are no longer found. A titer of 1:80 indicates that cold agglutinins can be detected when 1 part of the sample is diluted by adding up to 8 parts of saline solution. Higher numbers imply that there is a greater quantity of cold agglutinins in the blood. This indicates the possibility of infections such as pneumonia due to mycoplasma, malaria, infectious mononucleosis or other viral conditions. Cirrhosis, hepatitis C and autoimmune disease can also cause increased cold agglutinins levels.
Cold agglutinin syndrome is a condition in which the body's red blood cells are destroyed before time and the production of new cells are unable to make up for the loss. Other conditions that may cause high quantities of cold agglutinins include scleroderma, hemolytic anemia, rheumatoid arthritis and multiple myeloma. High titers of more than 1:1000 could be indicative of lymphoma. Titer levels that are very high can make an individual prone to blood clots when the body is exposed to cold temperature.