Antibody blood tests are done to detect those peculiar antibodies that start attacking body’s own red blood cells. Antibodies are essentially protein sequences generated by immune system in response to the entry of any foreign substance such as viruses and bacteria in our body.
Conditions leading to Antibody Synthesis
1) Blood Transfusion – Each blood cell is marked by a certain type of Antigen, which recognizes the foreign substance and signals antibody production. The antibody recognizes the special shape of the signalling antigen thus attaching to it to form Antigen-Antibody complex which is instrumental in eliminating the foreign particle.
* In Blood Transfusion it is essential that transfused blood should match your blood type with both having same antigens else an immune response is triggered leading to destruction of received blood cells. It is more commonly known as Transfusion Reaction.
2) Rhesus (Rh) factor Sensitization – Rh is an antigen. If a woman with Rh negative blood is pregnant with a baby with Rh positive blood, then it’s a potential situation for Rh Sensitization reaction. If the blood of the mother comes in contact with that of the baby then mother’s immune system will generate antibodies against the Rh positive blood cells of the child. In severe reactions it can lead to erythroblastosis fetalis leading to death of new-born or complications during further pregnancies.
3) Autoimmune Hemolytic Anaemia – A rare medical condition in which a person’s immune systems starts producing antibodies against their own blood cells.
Coomb’s Antibody Blood Test
This is an antibody blood test that detects the presence of lethal antibodies in your blood. It is of two types :-
- Direct Coomb’s Test : This antibody blood test is carried on a sample of red blood cells taken from the body to check the presence of antibodies that are already attached to them. In case of Rh positive baby and Rh negative mother this antibody blood test shows if there was any Rh sensitization and whether the antibodies from mother got transferred to the child. A normal antibody blood test result is Negative meaning absence of any lethal antibody.
- Indirect Coomb’s Test : This antibody blood test is carried with the blood serum of the donor or recipient before a blood transfusion to detect the presence of lethal antibodies in bloodstream. The normal result for this antibody blood test is Negative that shows blood transfusion is safe.