RBC reactions

Question 1

Agglutination

Hemagglutination

Answer 1

Clumping when antigens combine with antibodies.

NOT CLOTTING

Hemagluttination- agglutination test in which clumping of RBC indicates a positive reaction. (detecting A,B and Rh)

Question 2

How do you preform a cross-match test?

Answer 2

Use the recipients SERUM and test against the donors RBCs.

It will be the recipients antibodies that are enough in number to mount a response.

Question 3

Hemolytic transfusion reaction symptoms? and what happens to RBC?

Answer 3

Symptoms: fever, chills, shock, renal failure, and even death.

Recipients antibodies bind to transfused RBCs.
Causes complement fixation and rapid clearance of the RBCs

Question 4

Who can have chimeric blood?

Answer 4

Non identical twins, less than 10%. if shared blood supply.
Possible in people without twins if twin died before early in pregnancy.

Microchimeric
Multiparous women (many babies with different partners)
Multiple blood transfusions

Question 5

Bombay blood type. What does it have antibodies against?

Answer 5

Types as O, but it’s NOT! Missing Fucose.

Has antibodies against A, B, O

Still has D

Much higher prevalence in Mumbai.

Can only have Bombay blood group.

Question 6

Who needs a Rhogam?

Answer 6

Rh-negative mom with Rh-positive baby (Rh+ dad)

Mom builds up antibodies. Only very minor reaction to first baby.
Second Rh+ baby will be strongly reacted to.

Question 7

How does Rhogam work?

When is it given?

Answer 7

Anti-Rh IgG antibody binds fetal erythrocytes in the mothers circulation and prevents activation of the B cell.
Inhibition of B cells.

Given at 28 weeks and within 3 days after birth.