OVERVIEW
Agglutinins are antibodies that cause red blood cells to clump together.
? Cold agglutinins are active at cold temperatures.
? Febrile (warm) agglutinins are active at normal body temperatures.
Q. How is this test performed?
You’ll be pricked to collect a blood sample. This will be then sent to the laboratory where a dilution will be formulated out of it. All of them will be aired to various cool temperatures and will then be observed for at what degree do the RBCs make a cluster.
INTERPRETATION OF RESULTS
Normal results are:
- Warm agglutinins: no agglutination in titers at or below 1:80
- Cold agglutinins: no agglutination in titers at or below 1:16
The examples above are common measurements for results of these tests. Normal value ranges may vary slightly among different laboratories. Some labs use different measurements or test different samples. Talk to your doctor about the meaning of your specific test results.
What abnormal results mean
An abnormal (positive) result means there were agglutinins in your blood sample.
Warm agglutinins may occur with:
- Infections, including brucellosis, rickettsial disease, salmonella infection, and tularemia
- Inflammatory bowel disease
- Lymphoma
- Systemic lupus erythematosus
- Use of certain medicines, including methyldopa, penicillin, and quinidine
Cold agglutinins may occur with:
- Infections, such as mononucleosis and mycoplasma pneumonia
- Chicken pox (varicella)
- Cytomegalovirus infection
- Cancer, including lymphoma and multiple myeloma
- Listeria monocytogenes
- Systemic lupus erythematosus
- Waldenstrom macroglobulinemia
Why the Test is Performed?
This test is done to diagnose certain infections and find the cause of hemolytic anemia (a type of anemia that occurs when red blood cells are destroyed). Knowing whether there are warm or cold agglutinins can help explain why the hemolytic anemia is occurring and direct treatment.