Lecture 11

Question 1

Antibodies in plasma or serum

group A

Answer 1

has anti-B

Question 2

Antibodies in plasma or serum

group B

Answer 2

has anti-A

Question 3

Antibodies in plasma or serum

group AB

Answer 3

has neither

Question 4

Antibodies in plasma or serum

group O

Answer 4

has anti-A and anti-B

Question 5

Looking for presence or absence of antigens on the surface of RBCs
group A

Answer 5

has A antigen 40% of population

Question 6

antigens on the surface of RBCs

group B

Answer 6

has B antigen 11%

Question 7

antigens on the surface of RBCs

group C

Answer 7

has A and B 4 %

Question 8

antigens on the surface of RBCs

group O

Answer 8

has neither A nor B 45 % (most common)

Question 9

Blood Grouping

sample:

Answer 9

EDTA (lavender, pink )or red top; do not separate, refrigerate

Question 10

• direct or forward grouping looking for antigen on the surface

Answer 10

1 drop RBCs + 1 drop anti-A or anti-B

Question 11

• reverse or indirect grouping when looking for the antibody :

Answer 11

patient serum with commercial A or B cells(test for blood group antibodies)

Question 12

Other than the ABO and Rh blood group systems

Answer 12

some 20 blood group systems, such as Duffy, Kidd and Kell, on human red cells.

Question 13

Antigens on surface of RBCs – D is acquired not naturally in the body
Rh D+

Answer 13

has D antigen 85 % of population

Question 14

Antigens on surface of RBCs – D is acquired not naturally in the body
Rh D-

Answer 14

lack D antigen

Question 15

Antigens on surface of RBCs – D is acquired not naturally in the body
Rh Du

Answer 15

weak Rx but is D+ rare

Question 16

Antibodies: IgG type, occur after exposure to antigens

Rh D+

Answer 16

lacks anti-D

Question 17

Antibodies: IgG type, occur after exposure to antigens

Rh D-

Answer 17

anti-D if exposed to D Ag by transfusion or pregnancy

Question 18

Rh Typing

Answer 18

Patient RBCs + anti-D, heated on slide box to encourage agglutination by IgG

Question 19

Gel (solid Phase) Testing for Blood Group

Answer 19

• Card is pre –filled with gel and mixed with appropriate reagent
• Diluents of patients’ cells pipette on to gel and card incubated
• Card centrifuged and red
• Agglutination stays on top of gel
• No agglutination goes to the bottom

Look at slide
agglutination ring on top and no agglutination at the bottom

Question 20

A genotype:

Answer 20

the genes inherited from each parent’s blood group which are present on the chromosomes.

Question 21

A phenotype:

Answer 21

the observable effect of the inherited genes: that is, the blood group itself.

Question 22

The A and B genes

Answer 22

are dominant over the O gene and the phenotype A
can therefore arise from either the AO or the AA genotype.
Similarly, the phenotype B can arise from either the BO or the BB genotype.
look at slide for geno and phenotype

Question 23

Haemolytic Disease of the Newborn (HDN):

Answer 23

 when mother is Rh (–) and fetus is Rh (+); fetal cells enter maternal circulation during delivery
 mother develops anti-D (IgG) which destroys fetal RBCs in subsequent pregnancies
 mother given injection of RhD immunoglobulin (RhoGAM, RhIG) within 72 hrs of delivery to neutralize RhD antigens on fetal cells

Question 24

Cross Match (Blood Compatability Testing)	
Specimen:

Answer 24

Pink, lavender or red top; do not separate strict adherence to patient identification protocols

Question 25

``` Cross Match (Blood Compatability Testing) Procedure: ```

Answer 25

1. Both donor and recipient are ABO and Rh typed 2. Antibody Screen: recipient serum tested against a panel of cells for antibodies other than ABO 3. Recipient serum tested for reaction to donor cells look at slide

Question 26

Prenatal Screen | Specimen Sample

Answer 26

Specimen: red top or EDTA Procedure: ABO and Rh typing Antibody Screen

Question 27

Indirect Antiglobulin Test (IAT); Indirect Coombs Test; Antibody Screen specimen and sample

Answer 27

Specimen: serum or EDTA Procedure: patient serum is tested for antibodies to blood groups other than ABO; performed as part of cross match and as part of prenatal screen

Question 28

Direct Antiglobulin Test (DAT) Direct Coombs Test | specimen and sample

Answer 28

Specimen: red top or EDTA (need RBC’s) | Procedure: patient cells are tested for presence of bound antibodies

Question 29

Major cross match: for coombs test

Answer 29

recipient serum, donor cells,

Question 30

Minor cross match for coombs test

Answer 30

recipient cells, donor serum

Question 31

Computerized Crossmatch

Answer 31

Donor blood is issued to patient based on the blood bank information system to ensure that the patient and donor are ABO-compatible Method is usable only where patient has no clinically significant antibodies • donor ABO and Rh are confirmed and entered in the computer • donor unit identification number, component name, and ABO/Rh type are entered in the computer by scanning the bar code label on the unit Reduces : risk of accidents, errors, tampering

Question 32

Types of Transfusion Reaction

Answer 32

 Hemolytic: including DIC  Allergic: from hives to anaphylaxis  Febrile

Question 33

IgG

Answer 33

75% of total immunoglobulin intra and extravasular secondary reponse

Question 34

igM

Answer 34

0% of total immunoglobulin intravascular primary response

Question 35

igA

Answer 35

15% of total immunoglobulin intravascular and secretions protects mucus membranes

Question 36

igD

Answer 36

0.2% of total immunoglobulin lymphocyte surface unknown function

Question 37

igE

Answer 37

0.002% of total immunoglobulin basophils, mast cell in saliva and nasal secretions protect against parasites