Immunohematology

Question 1

We determine blood group and type so that:

Answer 1

we can safely transfuse and transplant organs

Question 2

First human-human blood transfusions:

Answer 2

Blundell, obstetrician, 1818 - worked 3/4 of the time

Question 3

First animal-human blood transfusions:

Answer 3

Denis, 1667, cow to human, worked a few times, then pt died -> outlawed

Question 4

First to describe ABO blood groups:

Answer 4

Karl Landsteiner, 1901

Question 5

Describe antigen/antibody presentation in blood types:

Answer 5

A - A antigen, B antibody
B - B antigen, A antibody
AB - A&B antigens, NO antibody
O - A&B antibody, NO antigens

Question 6

Antigen backbone?

Which blood types have it?

Answer 6

H antigen
A, B & O types have it! (only absent in Bombay phenotype)
Additional groups added to differentiate A & B antigens

Question 7

Who has auto-antibodies to their blood?

Answer 7

Everyone!

most of the time, they only work at severe temps that our bodies can’t survive at (hypothermia, pyrexia)

Question 8

Autoantibodies:

Answer 8

antibodies created to self

Question 9

Alloantibodies:

Answer 9

antibodies created to donor of same species

Question 10

Heterologous antibodies:

Answer 10

antibodies created to donor of other species

Question 11

Which blood typing is the only system that produces reciprocal antibodies without exposure?

Answer 11

ABO blood group system

Question 12

Complete (ABO) antibodies are what class?

Answer 12

IgM

Question 13

Isohemaglutinens are:

Answer 13

complete, naturally occurring antibodies directed against the A & B antigens

Question 14

Agglutination:

Answer 14

antibodies attach to multiple RBCs at the same time and hold them together

Question 15

Sensitization:

Answer 15

antibodies attach to single RBCs, but not held together

Question 16

Complement activation on RBCs:

Answer 16

C9 molecules form a cylinder (straw) into RBC, creates leaky membrane, hemoglobin leaks out into serum - Intravascular hemolysis

Question 17

Haptoglobin:

Answer 17

sponge, looks for free hemoglobin, immediately picks it up, taken up by liver to prevent damage.
levels drop in hemolysis

Question 18

Exposing patient RBCs to known A & B antibody reagent is called:

Answer 18

Forward Grouping

Question 19

Exposing patient serum to known A & B antibody reagent is called:

Answer 19

Reverse Grouping

Question 20

Mixing donor RBCs with recipient plasma to test for reaction is called:

Answer 20

Crossmatching

Question 21

At what level of agglutination is there concern?

Answer 21

Any agglutination is bad, and not transfusable!

rating scale is 0-4

Question 22

Universal donor:

Answer 22

O neg (no antibodies to agglutinate with any other type)

Question 23

Universal receiver:

Answer 23

AB pos (contains/accepts all antigens)

Question 24

Is blood type inherited?

Answer 24

Yes

Question 25

Antibodies to Rh are:

Answer 25

IgG | travel transplacentally

Question 26

RhoGam:

Answer 26

Rh immune globulin - given to Rh neg mother at 28 wks and delivery, to prevent an immune response to Rh pos fetal blood. DOESN'T WORK IF SHE'S ALREADY SENSITIZED

Question 27

Weak D:

Answer 27

appears Rh neg, with anti-D typing sera

Question 28

Direct antibody testing (DAT) detects:

Answer 28

In-vivo sensitization by Ab or complement | Rh

Question 29

Predominant blood type in the US:

Answer 29

O+