Cold agglutinins
What is analysed?
Cold agglutinins are antibodies that can cause red blood cells to clump together (agglutinate) at lower temperatures, typically below normal body temperature.
The cold agglutinins test detects the presence and level of cold agglutinins in the blood.
What does the result mean?
The result indicates the concentration of cold agglutinins in the body.
Why conduct the analysis?
The cold agglutinins test is conducted to determine the cause of a haemolytic anaemia, or to help diagnose cold agglutinin disease which can lead to haemolysis (destruction of red blood cells).
When to conduct the analysis?
The cold agglutinins test is conducted when symptoms associated with anaemia such as pain, skin paleness, or cyanosis (blue discolouration), are observed when the patient is exposed to cold temperatures – especially in the fingers and toes or at the top of the ears.
In addition, the analysis is also conducted after a diagnosis of haemolytic anaemia has been made, to determine the cause of the condition.
What sample is required?
A blood sample is required. The blood is drawn from a vein, usually in the arm.
Is any prior preparation necessary?
Patients should fast 8-12 hours before the sample is taken. In addition, patients should inform a healthcare professional about any medications being taken as they could affect results.
How is it performed?
The sample is sent to a laboratory, where it’s exposed to varying temperatures. The degree of agglutination is then observed microscopically and analysed.
What are the normal values?
Titres are used to measure the concentration of cold agglutinins.
A cold agglutinin titre of less than 1:80 is seen as a normal result.
What does having altered values mean?
- Elevated cold agglutinin titre: Indicates haemolytic anaemia, or other conditions such as mycoplasma pneumoniae infection, mononucleosis infection, and some types of cancer.