Immunohemotology ABO/Rh Flashcards
Most and least common groups
Most- O type
Least- AB Type
Red Blood Cell Antigens
A, B, AB, and O (and technically bombay)
Found on a lot of our bodies cells
Name the antibody class of most ABO isohemagglutinin
Most are the H antigen
Explain the ABO antigen situation in a person of Bombay blood type, and the consequences of a transfusion of non-Bombay blood into such a patient.
They lack a transferase that adds the terminal sugar that is required to make an a or b designation, so it can’t even modify. They find group O foreign, so they can only accept bombay antigens. But they look like O
Define the crossmatch, and explain why it is important. Explain how red cells are destroyed following a mismatched transfusion, and why this may be devastating to the recipient.
The crossmatch therefore is a lab test in which plasma from the prospective recipient is mixed with red cells from the prospective donor. This determines transfusion compatibility (you look for redness which means hemolysis of a mis match)
Define heterophile antibody, and identify a common disease in which one type is increased enough to be useful diagnostically.
It’s basically a cross reactive antibody. It’s helpful for determining mono and horse blood
Compare and contrast the techniques of the direct and indirect antiglobulin tests and the questions they are designed to answer.
DIrect- Is there Ab already on the blood?
Indirect- Does this serum contain Ab to blood?
Why do you tend to not give whole blood?
Because there would be residual plasma that is donor vs. recipeint that would also have antibodies
In Hemolytic Disease of the Newborn, explain the consequences of severe hemolysis in the newborn, the way in which the mother becomes sensitized, the class of antibody to Rh(D) the mother makes, the consequences of sensitization to subsequent fetuses, and the role of Rh-immune globulin.
You’ll have increase in bilirubin in the child because of RBC hemolysis, which could eventually cross the blood brain barrier, the mom, if RH- will be sensitized against RH+, meaning the first baby is fine, but subsequent babies will be bad.
Treatment: The disease is preventable if, at the time that the mother delivers her first Rh(D) baby, she is given IgG antibody to Rh(D) (Rh-immune globulin), the most familiar brand being Ortho’s RhoGAM. These antibodies combine with the fetal red cells, opsonizing them, and they are destroyed before they get a chance to immunize her.
