MAJOR EXAM

Question 1

Which of the following IgG subclass is/are the most efficient in crossing the placenta?

a. IgG1
b. IgG2
c. IgG3
d. IgG4
e. Both A and C
f. Both A and B

Answer 1

IgG1and IgG3 ( A and C)

Question 2

While performing routine postpartum testing for an Rh immune globulin candidate, a weakly positive antibody screening test was found. Anti-D was identified. This antibody is most likely the result of:

a. Massive fetomaternal hemorrhage occurring at the time of this delivery
b. Antenatal administration of RhIg at 28 weeks’ gestation
c. Contamination of the blood sample with Wharton’s jelly
d. Mother having a positive DAT

Answer 2

Massive fetomaternal hemorrhage occurring at the time of this delivery

Question 3

Titer of individuals after exposure to RhIg:

a. 1
b. 16
c. 32
d. 34
e. None of the above

Answer 3

34

Question 4

A phenomenon wherein accurate Rh testing can be difficult if the red cells are heavily coated with IgG anti D antibodies;

a. Partial D
b. Genetic weak D
c. Blocked Rh
d. Position effect

Answer 4

Blocked Rh

Question 5

AHG is used to detect what type of antibody:

a. warm reacting antibody
b. IgG
c. IgD
d. Both a and b
e. Both b and c

Answer 5

Both a and b

Question 6

Reagent added to counter check the result of Coombs test:

a. Anti-H
b. Group O IgM coated RBC
c. Group O IgG coated RBCs
d. NOTA

Answer 6

Group O IgG coated RBCs

Question 7

The following disease may cause a positive reaction to DAT except:

a. Lead poisoning
b. Infectious mononucleosis
c. Infectious hepatitis
d. Chronic granulomatous disease

Answer 7

Chronic granulomatous disease

Question 8

Direct antihuman globulin test is used to diagnose:

a. HDN
b. HTR
c. Autoimmune hemolytic anemia
d. AOTA

Answer 8

AOTA

Question 9

74. It is the reason why blood group O is used as reagent check cells in Coombs test.

a. Presence of expected antibodies
b. Absence of A and B antigens
c. It has more H antigens
d. None of the above

Answer 9

Absence of A and B antigens

Question 10

Reaction medium used in Antihuman globulin test which removes water in order to concentrate the antibodies present.

a. Albumin
b. DTT
c. Polyethylene glycol
d. LISS

Answer 10

Polyethylene glycol

Question 11

To validate the reaction obtained in the antiglobulin test, one can:

a. Use green antiglobulin reagent
b. Add IgG-coated red cells to each test tube
c. Add IgG-coated red cells to each positive reaction
d. Add IgG-coated red cells to each negative reaction

Answer 11

Add IgG-coated red cells to each negative reaction

Question 12

Type of immunoglobulin which is best in complement activation?

a. IgG
b. IgM
c. IgD
d. IgA

Answer 12

IgM

Question 13

Which of the following IgG subclass is not capable of complement activation?

a. IgG1
b. IgG2
c. IgG3
d. IgG4

Answer 13

IgG4

Question 14

The pentameric structure of IgM can be reduced into 5 monomers by the use of this agent:

a. Thiol
b. DTT
c. Albumin
d. PEG

Answer 14

DTT

Question 15

Demonstration of IgG coated RBCs would be best demonstrated by what test?

a. DAT
b. IAT
c. Elution
d. Treatment of DTT
e. None of the above

Answer 15

DAT

Question 16

Incubation period wherein most of the clinically significant antibodies are already reacting.

a. 120 minute
b. 10-15 minutes
c. 30 minutes
d. 15 minutes
e. None of the above

Answer 16

30 minutes

Question 17

A medical technologist performed forward typing, upon viewing the result microscopically there is presence of rouleaux formation, it can be resolve by:

a. DTT
b. 2-mercaptoethanol
c. Washing of RBCs
d. All of the above

Answer 17

Washing of RBCs

Question 18

Which of the following condition would demonstrate rouleaux formation upon testing:

a. Cord blood sample
b. Patients taking dextran
c. Patients with multiple myeloma
d. All f the above

Answer 18

All f the above

Question 19

Incomplete washing of RBCs during AHG testing would result into:

a. False negative result
b. Neutralization of AHG reagent
c. False positive result
d. Precipitation of sample
e. A and B
f. B and C

Answer 19

A and B

Question 20

What is the purpose of adding check cells for negative results in AHG testing:

a. Validate the test
b. Know if AHG reagent is added
c. A and B
d. None of the above

Answer 20

Know if AHG reagent is added

Question 21

AHG testing incubation can be shortened by adding which of the following potentiator.

a. DTT
b. 2-mercaptoethanol
c. Ficin
d. LISS
e. A and B

Answer 21

LISS

Question 22

Which of the following reagent can make cross-links between IgG coated RBCs:

a. LISS
b. PEG
c. AHG
d. 22% bovine albumin

Answer 22

AHG

Question 23

Failure to wash the red cells prior to performing a DAT will lead to:

a. False positives due to complement binding
b. False positives due to nonspecific globulin binding
c. False negatives due to unbound globulin binding
d. False negatives due to failure to remove unbound RBC antigens
e. None of the above

Answer 23

False negatives due to unbound globulin binding

Question 24

Using the low ionic strength solution medium (LISS) the equilibrium for most antigen antibody reaction is react within ________ minutes.

a. 30
b. 2 – 5
c. 10 – 15
d. 45

Answer 24

10 – 15

Question 25

A positive AHG phase result in the antibody identification procedure would mean that the antibody/antibodies is/are: 1. Warm 2. Cold 3. Clinically significant 4. Not clinically significant 5. IgG 6. IgM a. 1, 3,6 b. 2,4,6 c. 1,3,5 d. 1,3 (antibody type is indeterminate)

Answer 25

1,3,5

Question 26

Reaction medium used in Antihuman globulin test which removes water in order to concentrate the antibodies present. a. Albumin b. DTT c. Polyethylene glycol d. LISS

Answer 26

Polyethylene glycol

Question 27

Which among the following is true regarding the ABO blood group system: a. ABO antibodies are mostly IgG in nature b. ABO blood group is the most immunogenic c. ABO antigens are haptens in nature d. ABO is ISBT 004

Answer 27

ABO blood group is the most immunogenic

Question 28

This gene is said to be absent in a Bombay phenotype a. H gene b. Le gene c. ABO gene d. Z gene

Answer 28

H gene

Question 29

This antibody is present in Bombay phenotype that is not seen in a type O individual. a. Anti AB b. Anti A1 c. Anti H d. Anti A1B

Answer 29

Anti H

Question 30

Formation of the ABO antigen on the red cell is controlled by what gene? a. Se gene b. H gene c. Both d. Neither

Answer 30

H gene

Question 31

Formation of the ABO antigens on secretions is indirectly controlled by what gene? a. Se gene b. H gene c. Both d. Neither

Answer 31

Both

Question 32

The type of antibody that is against an antigen found on the own patients red cells a. Autoantibody b. Alloantibody c. Both d. Neither

Answer 32

Autoantibody

Question 33

What blood group would resemble bombay phenotype? a. O b. AB c. A d. NOTA

Answer 33

O

Question 34

Which of the following lectins differentiates A1 from A2 cells? a. Dolichos biflorus b. Salvia sclarea c. Glycine soya d. Ulex europaeus

Answer 34

Dolichos biflorus

Question 35

Anti H lectin would agglutinate which type of red blood cell: a. A cell b. O cell c. B cell d. AOTA

Answer 35

AOTA