Blood type test
What is being analysed?
Blood typing is a laboratory test that determines an individual's blood group. This test identifies specific proteins, called antigens, present on the surface of red blood cells. The most important antigens for blood typing are the A, B, and Rh (or D) antigens.
What are the different possible blood types?
There are four main blood types based on the presence or absence of certain antigens:
- Blood type A: has A antigens on red blood cells and B antibodies in the plasma.
- Blood type B: has B antigens on red blood cells and A antibodies in the plasma.
- Blood type AB: has both A and B antigens on red blood cells and no A or B antibodies in the plasma.
- Blood type O: has no A or B antigens on red blood cells and both A and B antibodies in the plasma.
Blood typing values:
Blood Type |
Antigens Present |
Antibodies Present |
Can Receive Blood From |
Can Donate Blood To |
---|---|---|---|---|
A+ |
A, Rh |
B |
A+, AB+ |
A+, O+ |
A- |
A |
B |
A+, A-, AB+, AB- |
A+, A-, AB+, AB- |
B+ |
B, Rh |
A |
B+, AB+ |
B+, O+ |
B- |
B |
A |
B+, B-, AB+, AB- |
B+, B-, AB+, AB- |
AB+ |
A, B, Rh |
None |
Universal Recipient |
AB+ |
AB- |
A, B |
None |
AB+, AB- |
AB+, AB- |
O+ |
Rh |
A, B |
O+, A+, B+, AB+ |
O+ |
O- |
None |
A, B |
O+, O- |
O+ ,O- |
Additionally, each blood type can be positive or negative based on the presence or absence of the Rh factor.
Why perform the analysis?
Blood typing is crucial for various medical procedures, including blood transfusions, organ transplants, and prenatal care. Matching blood types between donors and recipients reduces the risk of adverse reactions, such as haemolytic transfusion reactions.
When should the analysis be done?
Blood typing is typically performed:
- Before a blood transfusion to ensure compatibility.
- During pregnancy to assess potential risks of haemolytic disease of the newborn.
- Before organ transplantation to match donors and recipients.
What sample is required? Is any prior preparation necessary?
A small sample of blood is required for blood typing analysis. Prior preparation is usually not necessary, although it's essential to inform healthcare providers about any medications or medical conditions that might affect the results.
How is it used?
Blood typing results guide medical decisions such as:
- Selecting compatible blood for transfusions.
- Identifying potential risks during pregnancy.
- Matching donors and recipients for organ transplantation.
- Investigating blood relations in paternity tests.
Understanding your blood type is essential for maintaining good health and ensuring safe medical procedures. If you're unsure about your blood type or need further information, consult with your healthcare provider.