Minor antigens other than A, B, and Rh that occur on red blood cells can sometimes also cause problems. So they are also checked for a match before giving a blood transfusion.
Serious transfusion reactions are rare today because of blood type tests. Rh blood type checks for the Rh antigen also called the Rh factor on red blood cells. If your red blood cells:. If your blood has the B antigen but not the Rh antigen, your blood type is B-negative B—.
Rh blood type is even more important for pregnant women. A problem can occur when a woman who has Rh-negative blood becomes pregnant with a baby fetus that has Rh-positive blood. This is called Rh incompatibility. If the blood of an Rh-positive baby mixes with the blood of an Rh-negative mother during pregnancy or delivery, the mother's immune system makes antibodies. This antibody response is called Rh sensitization and, depending on when it occurs, can destroy the baby's red blood cells.
Rh sensitization does not generally affect the health of the baby during the pregnancy in which the sensitization occurs. But the health of a baby with Rh-positive blood during a future pregnancy is more likely to be affected.
After sensitization has occurred, the baby can develop mild to severe problems called Rh disease or erythroblastosis fetalis. In rare cases, if Rh disease is not treated, the baby may die. An Rh test is done in early pregnancy to check a woman's blood type. If she is Rh-negative, she can get a shot of Rh immunoglobulin that almost always prevents sensitization from occurring.
Problems from Rh sensitization have become very rare since Rh immunoglobulin was developed. In general, there's nothing you have to do before this test, unless your doctor tells you to. A health professional uses a needle to take a blood sample, usually from the arm.
When a blood sample is taken, you may feel nothing at all from the needle. Or you might feel a quick sting or pinch. There is very little chance of having a problem from this test. When a blood sample is taken, a small bruise may form at the site. The following table shows the compatibility of blood types between blood donors and recipients.
Read the table as follows: A person who has A-negative blood can receive A-negative or O-negative blood. Minor antigens other than A, B, and Rh on the red blood cells are also checked for a match before a blood transfusion. This matters because matching the correct blood type is critical to a successful blood transfusion or organ transplant as well a to the recipient's life.
If a person receives incompatible blood during a transfusion or organ donation, the body treats it as foreign and the immune system attacks the donated blood cells rather than incorporate them into the body. Such an attack can lead to serious problems, including kidney failure, shock, and a collapse of the circulatory system, In rare cases, receiving an incompatible blood donation can be fatal. Antigens determine how a blood recipient reacts to a blood transfusion.
An antigen is any substance the immune system can respond to. If the immune system encounters an antigen that is not found on the body's own cells, it will set off an attack to fight that antigen. There are seven blood types in addition to the universal recipient type.
The universal donor blood type is O negative. Anyone with this blood type can donate blood to a person who needs it regardless of their blood type. Blood types are characterized as positive or negative based on the presence or absence of a protein called Rh factor. Rh-negative blood is given to Rh-negative patients; Rh-positive or Rh-negative blood may be given to Rh-positive patients. There is a difference between a reaction caused by transfusing the wrong type of blood—which rarely is fatal—and an allergic reaction to the blood transfusion, which is possible regardless of blood type.
A hemolytic transfusion reaction can occur when there is a mismatch between A, B, and O blood types of the donor and recipient. Antibodies in the recipient's blood attach to the donor red cells, and are then destroyed in the recipient's bloodstream, liver, and spleen. This can lead to jaundice and may cause uncontrolled clotting in the bloodstream, shock, and rarely death. Hemolytic transfusions reactions are divided into two categories: acute and delayed hemolytic reactions.
Acute reactions happen within 24 hours of a transfusion and delayed reactions occur after 24 hours. Delayed reactions may happen two weeks to 30 days after a transfusion. An allergic reaction to a blood transfusion is not caused by a blood type mismatch.
It is caused by the recipient's body identifying the blood as a foreign invader. The immune system then attempts to destroy the foreign cells. Also known as an acute non-hemolytic transfusion reaction, this type of reaction results in itching, fever, chills, itching, and a rash.
Unlike the reaction that happens when a person receives the wrong blood type, the reaction the body has to the blood that is identified as "foreign" can be treated effectively. A person who has a severe type of reaction to a blood transfusion may require more thoroughly screened blood in the future to prevent a similar reaction with subsequent transfusions.
Receiving a blood transfusion is not the only time being a universal blood recipient matters. A person who needs an organ transplant could also potentially benefit from being a universal recipient. A patient who needs an organ and has AB positive blood can accept an organ from donors of all blood types, just as they can accept blood of any type. The organ allocation system is also set up so that the distribution of organs is fair. That way, people with AB blood don't receive an unfair percentage of organs while recipients with other blood types receive fewer.
Individuals with AB positive blood are able to accept blood from donors of all blood types. The demand for O-negative blood type is the highest due to its need during emergencies. The blood type or the blood group is a form of classification of blood that depends on the presence and absence of antibodies and inherited antigens on the surface of red blood cells.
Our blood contains red blood cells, white blood cells, and platelets in a liquid called plasma. Antigens are molecules found on the surfaces of the red blood cells and contain protein and carbohydrates. Antibodies are protein molecules called Immunoglobulins Ig found in plasma. Antibodies bind specifically to the corresponding antigen on the red blood cells. Antibodies are our natural defense mechanisms and are produced by the immune system when there is exposure to a foreign antigen.
Simply put, the people with type O negative blood are universal red cell donors, and people with type AB blood group are universal plasma donors. The absence or presence of some antigens determines the blood types. An antigen is any molecule that pushes your immune system to produce antibodies to fight it. Besides, the presence or absence of the Rh factor, a protein, determines if your blood group would be negative or positive.
It is crucial to ensure that the blood type of the donor and recipient are matching when it comes to blood transfusions. Some antigens can make your immune system consider the transfused blood as a foreign body and attack it. Therefore, cross-matching and correct blood-typing are critical. Hence, during blood transfusions, an agglutination reaction occurs between similar antigen and antibody. Agglutination means the clumping of particles. If the antigen and antibodies are not similar, the antibody will attack the antigen as a defensive action by the immune system.
This also explains why O type is a universal donor since it has no antigens present in the first place to be attacked by antibodies. Similarly, AB type is a universal recipient since it does not have any antibodies present in order to attack antigens. It is known as the Rh system. Rh, meaning Rhesus system, contains 49 blood group antigens, out of which five are most significant. The most significant Rh antigen is the D antigen because it is the most likely to provoke an immune system response of the five main Rh antigens.
As mentioned earlier, the O- blood type can be safely given to any person with any blood type since it does not contain any A, B, or RhD antigens on the surface of the red blood cells. Hence, it is compatible with every other blood group of the ABO and Rh system. The person can receive blood from any type but can only donate to AB type.
Blood transfusion is a way of infusing blood into the body after an illness or injury. Some of the many cases where you may need blood transfusions are:. To determine your blood group, a lab technician will mix your blood sample with antibodies that attack types A and B blood to see how it reacts.
Then, they will check it to see if agglutination clumping is taking place or not. For example, your blood type is B, and the technician mixed the sample with an anti-Rh serum. If your blood cells clump together in response to the anti-Rh serum, it means that you have Rh-positive blood.
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