Antierthrocyte Antibodies (Indirect Coombs Test)
What is being analysed?
The indirect Coombs test, also known as the screening of antierthrocyte antibodies, is a laboratory procedure that examines the presence of antibodies in the blood that can target and attack red blood cells.
What does the result mean?
The test results indicate whether antibodies are present in the blood. A positive result suggests the presence of antibodies, which can have implications for various medical conditions, including autoimmune disorders and certain types of haemolytic anaemia.
Why undergo the analysis?
The analysis is conducted to identify and diagnose conditions where the immune system produces antibodies that may harm red blood cells. It is often ordered when there is suspicion of autoimmune haemolytic anaemia, haemolytic disease of the newborn, or as a pre-transfusion screening.
When to perform the analysis?
The test is typically performed in the following situations:
Before blood transfusions to ensure compatibility. In pregnant women to assess the risk of haemolytic disease in the newborn. When autoimmune haemolytic anaemia is suspected.
Required sample:
A small blood sample is required for the analysis. The sample is usually drawn from a vein in the arm.
Is any prior preparation necessary?
No specific preparation is usually required before the test. However, individuals should inform their healthcare provider about any medications or supplements they are taking.
How is it conducted?
The procedure involves taking a blood sample, which is then mixed with specific reagents to detect the presence of antibodies. The sample is observed for agglutination (clumping), indicating the presence of antibodies.
Normal values:
Normal values for the indirect Coombs test typically show no agglutination, indicating the absence of antibodies. Results may vary slightly between laboratories.
Test Result
Interpretation
Negative
No antibodies detected
Positive
Presence of antibodies detected
Significance of abnormal values:
Abnormal values, such as agglutination, suggest the presence of antibodies. Depending on the clinical context, abnormal results may indicate autoimmune disorders, haemolytic anaemias, or other conditions that require further evaluation.