Blood Groups & Matching

Question 1

What is a H antigen?

Answer 1

An ABO antigen precursor

Question 2

What are A & B antigens?

Answer 2

Complex oligosaccharides, terminal sugar is different for each rxn from each enzyme that catalyse transfer of sugar units.

Question 3

What does an H antigen contain?

Answer 3

glucose-galactose-N-acetylglucosamine-galactose-fucose

Question 4

What blood type does H antigen give rise to?

Answer 4

Type O

Question 5

What does an A antigen contain?

Answer 5

N-acetylgalactosamine bonded to end of H antigen

Question 6

What blood type does A antigen give rise to?

Answer 6

Type A

Question 7

What does a B antigen contain?

Answer 7

Galactose bonded to end of H antigen

Question 8

What blood type does B antigen give rise to?

Answer 8

Type B

Question 9

What is erythroblastosis fetalis and how is it treated?

Answer 9

1. Haemolysis of RBCs of fetus which causes anemia or worse. May occur when an Rh- mother & Rh+ father have an Rh+ fetus
2. Treated with Rho(D) globulin (RhoGAM). Injected within 24-72hrs after birth of Rh+ baby

Question 10

How is giving a patient the wrong blood dangerous?

Answer 10

Donor’s cells will agglutinate which causes them to clump, blocking capillaries and RBCs usually rupture causing haemoglobin to precipitate in kidneys, interfering with function.