why would a person with blood type A exibit a transfusion reaction if given type B blood?

Answer 1

the antigen would not be the same and the other persons body would attack the wrong blood type causing clots and that would cause massive strokes and heart attacks to take place and then death.

Answer 2

Transfusion reactions occur based on the activity and presence of two things. One contributing factor is antibodies, the other is an antigen.

A person with type A blood will have "A antigens" and "anti-B antibodies". The "A antigen" is located on the red blood cell (RBC). The antigen is a chemical complex on the outside of the RBC. The presence of this antigen is what distinguishes blood types (A and B). When both antigens are present on the RBC, the blood type is AB. When neither antigen is found, the blood type is O.

Since the type A blood also contains "anti-B antibodies", that means that a person with type A blood has antibodies that fight type B blood. The reverse is true for type B blood (type B blood has anti-A antibodies". But interestingly, AB blood contains no antibodies because both anitgens are present.

When type B blood is given to a type A person, the antigens on the type B blood will sensitize the anti-B antibodies, resulting in an anitgen-antibody reaction. The reaction is the antibodies fighting the transfused blood. This causes massive blood clots in every part of the body. Death is usually a result of such a mistake unless intervened quickly with immuno suppressors.

The immune system of the type A blood will automatically attack type B blood, and vice versa. The immune system of a type AB blood will not fight A or B blood. Since type O blood does not contain any antigens, it can be given to anyone. But since type O blood does not contain antigens, it contains anti-A and anti-B antibodies. This means that a type O blood person cannot receive blood from either type A, B, or AB.

NOTE: I have not mentioned the RH factor. You should be aware that RH factor has as much to do with transfusion reactions as blood type. Since the question did not mention RH, I am assuming my answer should be sufficient.

Answer 3

It's because of an antibody reaction. Each blood type has it's own specific antibodies that other types see as a foreign substance and will typically attack them. This makes the patient have a terrible or even fatal reaction to it.
People with type O are in such demand because their cells don't have any of the antibodies on them that could make the patients' blood see it as foreign, so no reaction.

Answer 4

The body will reject it because it sees it as foreign. You must be transfused with your blood type. Using a different type could kill you.

Answer 5

antigens and antibodies

Answer 6

intravenous coagulation