BB

Question 1

1. What type of serological testing does the blood bank technologist perform when determining the blood group of a patient?
   A. Genotyping
   B. Phenotyping
   C. Both genotyping and phenotyping
   D. Polymerase chain reaction
   Blood bank/Apply knowledge of laboratory operations/Genetics/1

Answer 1

B Phenotyping, or the physical expression of a genotype, is the type of testing routinely

Question 2

2. If anti-K reacts 3+ with a donor cell with a genotype KK and 2+ with a Kk cell, the
   antibody is demonstrating:
   A. Dosage
   B. Linkage disequilibrium
   C. Homozygosity
   D. Heterozygosity
   Blood bank/Apply knowledge of fundamental biological characteristics/Genetics/Kell/3

Answer 2

A Dosage is defined as an antibody reacting stronger with homozygous cells (e.g., KK) than with heterozygous cells (e.g., Kk). In addition to Kell, dosage effect is seen commonly with antigens M, N, S, s, Fya, Fyb, Jka, Jkb, and the antigens of the Rh system.

Question 3

3. Carla expresses the blood group antigens Fya, Fyb, and Xga. James shows expressions of
   none of these antigens. What factor(s) may account for the absence of these antigens in
   James?
   A. Gender
   B. Race
   C. Gender and race
   D. Medication
   Blood bank/Apply knowledge of fundamental biological characteristics/Genetics/2

Answer 3

C The frequency of Duffy antigens Fya and Fyb varies with race. The Fy(a-b-) phenotype
occurs in almost 70% of African Americans and is very rare in whites. Xga antigen is
X-linked and, therefore, expressed more frequently in women (who may inherit the
antigen from either parent) than in men.

Question 4

4. Which of the following statements is true?
   A. An individual with the BO genotype is homozygous for B antigen
   B. An individual with the BB genotype is homozygous for B antigen
   C. An individual with the OO genotype is heterozygous for O antigen
   D. An individual with the AB phenotype is homozygous for A and B antigens
   Blood bank/Apply knowledge of fundamental biological characteristics/Genetics/ABO/1

Answer 4

B An individual having the BB genotype has inherited the B gene from both parents and,
therefore, is homozygous for B antigen.

Question 5

5. Which genotype is heterozygous for C?
   A. DCe/dce
   B. DCE/DCE
   C. Dce/dce
   D. DCE/dCe
   Blood bank/Apply knowledge of fundamental biological characteristics/Genetics/Rh/2

Answer 5

A The genotype DCe/dce contains one C and one c gene and is heterozygous for C and c
antigens.

Question 6

6. Which genotype(s) will give rise to the Bombay phenotype?
   A. HH only
   B. HH and Hh
   C. Hh and hh
   D. hh only
   Blood bank/Apply knowledge of fundamental biological characteristics/ABO/Bombay/1

Answer 6

D The Bombay phenotype will be expressed only when no H substance is present. The
Oh type is expressed by the genotype hh. Bombay phenotypes produce naturally
occurring anti-H, and their serum agglutinates group O red blood cells (RBCs) in
addition to RBCs from persons who are groups A, B, and AB.

Question 7

7. Meiosis in cell division is limited to the ova and sperm producing four gametes
   containing what complement of DNA?
   A. 1N
   B. 2N
   C. 3N
   D. 4N
   Blood bank/Apply knowledge of fundamental biological characteristics/Genetics/1

Answer 7

A Meiosis involves two nuclear divisions in succession resulting in four gametocytes,
each containing half the number of chromosomes found in somatic cells or 1N.

Question 8

8. A cell that is not actively dividing is said to be in:
   A. Interphase
   B. Prophase
   C. Anaphase
   D. Telophase
   Blood bank/Apply knowledge of fundamental biological characteristics/Genetics/1

Answer 8

A Interphase is the stage in between cell divisions. The cell is engaged in metabolic
activity. Chromosomes are not clearly discerned; however, nucleoli may be visible

Question 9

9. Which of the following describes the expression of most blood group antigens?
   A. Dominant
   B. Recessive
   C. Codominant
   D. Corecessive
   Blood bank/Apply knowledge of fundamental biological characteristics/Genetics/1

Answer 9

C The inheritance of most blood group genes is codominant, meaning that no gene or
allele is dominant over another. For example, a person who is group AB expresses both
the A and B antigen on his or her RBCs.

Question 10

10. What blood type is not possible for an offspring of an AO and BO mating?
    A. AB
    B. A or B
    C. O
    D. All are possible
    Blood bank/Apply knowledge of fundamental biological characteristics/Genetics/ABO/2

Answer 10

D A mating between AO and BO persons can result in an offspring with blood type A,
B, AB, or O.

Question 11

11. The alleged father of a child in a disputed case of paternity is blood group AB. The
    mother is group O, and the child is group O. What type of exclusion is this?
    A. Direct/primary/first order
    B. Probability
    C. Random
    D. Indirect/secondary/second order
    Blood bank/Evaluate laboratory data to verify test results/Genotype/Paternity testing/2

Answer 11

D An indirect/secondary/second order, exclusion occurs when a genetic marker is absent
in the child but should have been transmitted by the alleged father. In this case, either
A or B should be present in the child.

Question 12

12. If the frequency of gene Y is 0.4 and the frequency of gene Z is 0.5, one would expect
    that they should occur together 0.2 (20%) of the time. In actuality, they are found
    together 32% of the time. This is an example of:
    A. Crossing over
    B. Linkage disequilibrium
    C. Polymorphism
    D. Chimerism
    Blood bank/Apply principles of genetics/3 Answers to Questions 6–12

Answer 12

B Linkage disequilibrium is a phenomenon in which alleles situated in close proximity
on a chromosome associate with one another more than would be expected from
individual allelic frequencies.

Question 13

13. In the Hardy-Weinberg formula, p2 represents:
    A. The heterozygous population of one allele
    B. The homozygous population of one allele
    C. The recessive allele
    D. The dominant allele
    Blood bank/Apply knowledge of fundamental biological characteristics/Genetics/1

Answer 13

B In the Hardy-Weinberg formula (p2 + 2pq + q2), p2 and q2 represent homozygous
expressions, and 2pq represents heterozygous expression. This formula is used in
population genetics to determine the frequency of different alleles.

Question 14

14. In this type of inheritance, the father carries the trait on his X chromosome. He has no
    sons with the trait because he passed his Y chromosome to his sons; however, all his
    daughters will express the trait.
    A. Autosomal dominant
    B. Autosomal recessive
    C. X-linked dominant
    D. X-linked recessive

Answer 14

C In X-linked dominant inheritance, there is absence of male-to-male transmission because a male passes his Y chromosome to all of his sons and his single X
chromosome to all his daughters. All daughters who inherit the affected gene will
express the trait. An example of this type of inheritance is the Xga blood group.

Question 15

15. Why do immunoglobulin M (IgM) antibodies, such as those formed against ABO
    antigens, have the ability to directly agglutinate RBCs and cause visible agglutination?
    A. IgM antibodies are larger molecules and have the ability to bind more antigen
    B. IgM antibodies tend to clump together more readily to bind more antigen
    C. IgM antibodies are found in greater concentrations than IgG antibodies
    D. IgM antibodies are not limited by subclass specificity
    Blood bank/Apply knowledge of fundamental biological characteristics/Antibodies/1

Answer 15

A An IgM molecule has the potential to bind up to 10 antigens compared with a
molecule of IgG, which can bind only two.

Question 16

16. Which of the following enhancement mediums decreases the zeta potential, allowing
    antibody and antigen to come closer together?
    A. Low ionic strength solution (LISS)
    B. Polyethylene glycol
    C. Polybrene
    D. Dithiothreitol-papain (ZZAP)
    Blood bank/Apply knowledge of fundamental biological characteristics/Antigens/1

Answer 16

A LISS contains a reduced concentration of NaCl (0.2%) and results in a reduction in
charged ions within the ionic cloud, decreasing the zeta potential and facilitating
antigen–antibody interaction

Question 17

17. This type of antibody response is analogous to an anamnestic antibody reaction.
    A. Primary
    B. Secondary
    C. Tertiary
    D. Anaphylactic
    Blood bank/Apply knowledge of fundamental biological characteristics/Antibodies/1

Answer 17

B An anamnestic response is a secondary immune response in which memory
lymphocytes respond rapidly to foreign antigen in producing specific antibody. The
antibodies are IgG and are produced at lower doses of antigen than in the primary
response.

Question 18

18. Which antibodies to a component of complement are contained in the rabbit
    polyspecific anti-human globulin (AHG) reagent for detection of in vivo sensitization?
    A. Anti-IgG and anti-C3a
    B. Anti-IgG and anti-C3d
    C. Anti-IgG and anti-IgM
    D. All of these options
    Blood bank/Apply knowledge of fundamental biological characteristics/AHG/2

Answer 18

B In the direct antiglobulin test (DAT), rabbit polyspecific antisera contains both an
anti-human IgG component and an antibody against the C3d component of
complement.

Question 19

1. Which of the following distinguishes the A1 blood group from the A2 blood group?
   A. A2 antigen will not react with anti-A, A1 will react strongly (4+)
   B. An A2 person may form anti-A1; an A1 person will not form anti-A1
   C. An A1 person may form anti-A2, an A2 person will not form anti-A1
   D. A2 antigen will not react with anti-A from a nonimmunized donor; A1 will react with any
   anti-A
   Blood bank/Apply knowledge of fundamental biological characteristics/ABO blood group/2

Answer 19

B The group A1 comprises both A1 and A antigens. Anti-A will react with both A1- and
A2-positive RBCs. A person who is group A2 may form anti-A1, but an A1 person will
not form anti-A1 (which would cause autoagglutination).

Question 20

2. A patient’s serum is incompatible with O cells. The patient RBCs give a negative
   reaction to anti-H lectin. What is the most likely cause of these results?
   A. The patient may be a subgroup of A
   B. The patient may have an immunodeficiency
   C. The patient may be a Bombay phenotype individual
   D. The patient may have developed alloantibodies
   Blood bank/Apply principles of special procedures/ABO blood group/3

Answer 20

C Bombay phenotype is the only ABO phenotype incompatible with O cells. The RBCs
of a Bombay phenotype individual show a negative reaction to anti-H because the cells
contain no H substance.

Question 21

3. What antibodies are formed by a Bombay phenotype individual?
   A. Anti-A and anti-B
   B. Anti-H
   C. Anti-A,B
   D. Anti-A, B, and H
   Blood bank/Apply knowledge of fundamental biological characteristics/ABO blood
   group/Bombay/1

Answer 21

D A Bombay phenotype individual does not express A, B, or H antigens; therefore, anti-
A, -B, and -H are formed. Because a Bombay phenotype individual has three
antibodies, the only compatible blood must be from another Bombay phenotype donor

Question 22

4. Acquired B antigens have been found in:
   A. Bombay phenotype individuals
   B. Group O persons
   C. Persons of all blood groups
   D. Group A persons
   Blood bank/Apply knowledge of fundamental characteristics/ABO/1

Answer 22

D The acquired B phenomenon is only seen in group A persons.

Question 23

5. Blood is crossmatched on an A-positive person with a negative antibody screen. The
   patient received a transfusion of A-positive RBCs 3 years ago. The donors chosen for
   crossmatching were A-positive. Crossmatching was run on the automated analyzer and
   yielded 3+ incompatibility. How can these results be explained?
   A. The patient has an antibody to a low-frequency antigen
   B. The patient has an antibody to a high-frequency antigen
   C. The patient is an A2 with anti-A1
   D. The patient is an A1 with anti-A2
   Blood bank/Apply principles of special procedures/ABO/3

Answer 23

C The patient is likely an A2 with anti-A1, which is causing reactivity in the
crossmatching. A negative antibody screen rules out the possibility of an antibody to a
high-frequency antigen, and two donor units incompatible rules out an antibody to a
low-frequency antigen.

Question 24

6. A patient’s RBCs forward as group O, serum agglutinates B cells (4+) only. Your next
   step would be:
   A. Extend reverse typing for 15 minutes
   B. Perform an antibody screen, including room-temperature incubation
   C. Incubate washed RBCs with anti-A1 and anti-A,B for 30 minutes at room temperature
   D. Test patient’s RBCs with Dolichos biflorus
   Blood bank/Apply principles of special procedures/RBCs/ABO discrepancy/3

Answer 24

C The strong 4+ reaction in reverse grouping suggests the discrepancy is in forward
grouping. Incubating washed RBCs at room temperature with anti-A and anti-A,B will
enhance reactions.

Question 25

7. Which typing results are most likely to occur when a patient has an acquired B antigen?
   A. Anti-A 4+, anti-B-3+, A1 cells neg, B cells neg
   B. Anti-A 3+, anti-B neg, A1 cells neg, B cells neg
   C. Anti-A 4+, anti-B 1+, A1 cells neg, B cells 4+
   D. Anti-A 4+, anti-B 4+, A1 cells 2+, B cells neg

Answer 25

C In forward typing, a 1+ reaction with anti-B is suspicious because of the weak reaction
and the normal reverse grouping that appears to be group A. This may be indicative of
an acquired antigen. In the case of an acquired B antigen, the reverse grouping is the
same for a group A person. Choice A is indicative of group AB; choice B is indicative
of a group A who may be immunocompromised. Choice D may be caused by a
mistyping or an antibody against antigens on reverse cells.

Question 26

8. Which blood group has the least amount of H antigen?
   A. A1B
   B. A2
   C. B
   D. A1
   Blood bank/Apply knowledge of fundamental biological principles/ABO/1

Answer 26

A The A1B blood group has the least amount of H antigen. This occurs because both A
and B epitopes are present on RBCs, compromising the availability of H epitopes. A1B
cells will yield weak reactions with anti-H lectin.

Question 27

9. What type RBCs can be transfused to an A2 person with anti-A1?
   A. A only
   B. A or O
   C. B
   D. AB
   Blood bank/Apply knowledge of fundamental biological principles/ABO/3

Answer 27

B A person who is in need of RBC transfusion and is an A2 with anti-A1 can be
transfused with A or O cells because the anti-A1 is typically only reactive at room
temperature.

Question 28

10. What should be done if all forward and reverse ABO results as well as the autocontrol
    are positive?
    A. Wash the cells with warm saline, and autoadsorb the serum at 4°C
    B. Retype the sample using a different lot number of reagents
    C. Use polyclonal typing reagents
    D. Report the sample as group AB
    Blood bank/Evaluate laboratory and clinical data to specify additional tests/RBCs/ABO
    discrepancy/3

Answer 28

A These results point to a cold autoantibody. Washing the cells with warm saline may
elute the autoantibody, allowing a valid forward type to be performed. The serum
should be adsorbed using washed cells until the autocontrol is negative. Then, the
adsorbed serum should be used for reverse typing.

Question 29

11. What should be done if all forward and reverse ABO results are negative?
    A. Perform additional testing, such as typing with anti-A1 lectin and anti-A,B
    B. Incubate at 22°C or 4°C to enhance weak expression
    C. Repeat the test with new reagents
    D. Run an antibody identification panel
    Blood bank/Evaluate laboratory and clinical data to specify additional tests/RBCs/ABO
    discrepancy/3

Answer 29

B All negative results may be caused by weakened antigens or antibodies. Room
temperature or lower incubation temperature may enhance expression of weakened
antigens or antibodies

Question 30

12. N-acetyl-D-galactosamine is the immunodominant carbohydrate that reacts with:
    A. Arachis hypogaea
    B. Salvia sclarea
    C. Dolichos biflorus
    D. Ulex europeaus
    Blood bank/Apply knowledge of fundamental biological principles/ABO/2

Answer 30

C The immunodominant sugar N-acetyl-galactosamine confers A antigen specificity
when present at the terminus of the type 2 precursor chain on the RBC membrane.
Therefore, its presence would cause RBCs to react with anti-A1 lectin, Dolichos
biflorus

Question 31

A stem cell transplant recipient was retyped when she was transferred from another hospital. What is the most likely cause of the following results?
Patient cells: Anti-A: neg; Anti-B: 4+
Patient serum: A1 cells: neg; B cells: neg

A. Viral infection
B. Alloantibodies
C. Immunodeficiency
D. Autoimmune hemolytic anemia

Answer 31

C The transplant recipient is probably taking immunosuppressive medication to increase
graft survival. This can contribute to the loss of normal blood group antibodies as well
as other types of antibodies

Question 32

14. What reaction would be the same for an A1 and an A2 person?
    A. Positive reaction with anti-A1 lectin
    B. Positive reaction with A1 cells
    C. Equal reaction with anti-H
    D. Positive reaction with anti-A,B
    Blood bank/Evaluate laboratory data to make identifications/ABO discrepancy/2

Answer 32

D Anti-A,B should react positively with group A or B and any subgroup of A or B (with
exception of Am). An A1 (not A2) would react with anti-A1 lectin; only an A2 person
with anti-A1 would give a positive reaction with A1 cells; an A2 would react more
strongly with anti-H than A1.

Question 33

15. A female patient at 28 weeks’ pregnancy yields the following results:
    Patient cells: Anti-A: 3+; Anti-B: 4+
    Patient serum: A1 cells: neg; B cells: 1+; O cells: 1+
    Which of the following could be causing the ABO discrepancy?
    A. Hypogammaglobulinemia
    B. Alloantibody in patient serum
    C. Acquired B
    D. Weak subgroup
    Blood bank/Evaluate laboratory data to make identifications/ABO discrepancy/3

Answer 33

B The patient is most likely an AB person who has formed a cold-reacting alloantibody
reacting with B cells and O cells. An identification panel should be performed. An
acquired B person or someone with hypogammaglobulinemia should not make
antibody that would agglutinate O cells.

Question 34

16. Which condition would most likely be responsible for the following typing results?
    Patient cells: Anti-A: neg; Anti-B: neg
    Patient serum: A1 cells: neg; B cells: 4+
    A. Immunodeficiency
    B. Masking of antigens by the presence of massive amounts of antibody
    C. Weak or excessive antigen(s)
    D. Impossible to determine
    Blood bank/Apply principles of basic laboratory procedures/ABO discrepancy/3

Answer 34

C Excessive A substance, as may be found in some types of tumors, may be neutralizing
anti-A. Weak A subgroups may fail to react with anti-A and require additional testing
techniques (e.g., room-temperature incubation) before their expression is apparent.

Question 35

17. Which of the following results is most likely discrepant?
    Anti-A, neg Anti-B, 4+
    A1 cells, neg B cells, neg
    A. Negative B cells
    B. Positive reaction with anti-B
    C. Negative A1 cells
    D. No problem with this typing

Answer 35

C The reverse typing should agree with the forward typing in this result. The 4+
reaction with anti-B indicates group B. A positive reaction is expected with A1 cells in
the reverse group.

Question 36

18. A 61-year-old male with a history of multiple myeloma underwent stem cell
    transplantation 3 years ago. The donor was O positive, and the recipient was B positive.
    The patient is admitted to a community hospital for fatigue and nausea. Typing results
    reveal the following:
    Anti-A = 0
    Anti-B =0
    Anti-A,B = 0
    Anti-D = 4+
    A1 cells = 4+
    B cells = 0
    How would you report this type?
    A. O positive
    B. B positive
    C. A positive
    D. Undetermined

Answer 36

D In a transplantation scenario, there are no methods to employ to solve the
discrepancy. The medical laboratory scientist must rely on the patient history of donor
type and recipient type and the present serological picture. Giving a B-positive
recipient an O-positive transplant constitutes a minor ABO mismatch. The forward
type resembles the donor. The reverse type still resembles the recipient. The ABO type
reported out does not fit a pattern resulting in an undetermined type.

Question 37

1. A complete Rh typing for antigens C, c, D, E, and e revealed negative results for C, D,
   and E. How is the individual designated?
   A. Rh positive
   B. Rh negative
   C. Positive for c and e
   D. Impossible to determine
   Blood bank/Apply knowledge of fundamental biological characteristics/Rh typing/1

Answer 37

B Rh positive refers to the presence of D antigen; Rh negative refers to the absence of D
antigen. These designations are for D antigen only and do not involve other Rh
antigens.

Question 38

2. How is an individual with genotype Dce/dce classified?
   A. Rh positive
   B. Rh negative
   C. Rhnull
   D. Total Rh
   Blood bank/Apply knowledge of fundamental biological characteristics/Rh typing/2

Answer 38

A This individual has D antigen and is classified as Rh positive. Any genotype containing
D antigen will be considered Rh positive

Question 39

3. If a patient has a positive DAT, should you perform a weak D test on the cells?
   A. No, the cells are already coated with antibody
   B. No, the cells are Rhnull
   C. Yes, the immunoglobulin will not interfere with the test
   D. Yes, Rh reagents are enhanced in protein media
   Blood bank/Apply knowledge of fundamental biological characteristics/Rh typing/3

Answer 39

A If a person has a positive DAT, the RBCs are coated with immunoglobulin. If a test for
weak D were performed, the test would yield positive results independent of the
presence or absence of D antigen on the RBCs.

Question 40

4. Which donor unit is selected for a recipient with anti-c?
   A. r´r
   B. R0R1
   C. R2r´
   D. r´ry
   Blood bank/Apply knowledge of fundamental biological characteristics/Rh typing/3

Answer 40

D The designation r’ is dCe and ry is dCE, neither of which contains c antigen. The other
three Rh types contain c antigen and could not be used in transfusion for a person with
anti-c.

Question 41

5. Which genotype usually shows the strongest reaction with anti-D?
   A. DCE/DCE
   B. Dce/dCe
   C. D–/D–
   D. –CE/–ce
   Blood bank/Apply knowledge of fundamental biological characteristics/Rh typing/1

Answer 41

C The phenotype that results from D–/D– is classified as enhanced D because it shows a
stronger reaction than expected with anti-D. Such cells have a greater amount of D
antigen than normal. This is thought to result from a larger quantity of precursors being
available to the D genes because there is no competition from other Rh genes.

Question 42

6. Why is testing for Rh antigens and antibodies different from ABO testing?
   A. ABO reactions are primarily caused by IgM antibodies and usually occur at room
   temperature; Rh antibodies are IgG and agglutination usually requires a 37°C incubation
   and enhancement media
   B. ABO antigens are attached to receptors on the outside of the RBC and do not require any
   special enhancement for testing; Rh antigens are loosely attached to the RBC membrane
   and require enhancement for detection
   C. Both ABO and Rh antigens and antibodies have similar structures, but Rh antibodies are
   configured so that special techniques are needed to facilitate binding to Rh antigens
   D. There is no difference in ABO and Rh testing; both may be conducted at room
   temperature with no special enhancement needed for reaction
   Blood bank/Apply knowledge of fundamental biological characteristics/Rh system/1

Answer 42

A Detection of ABO and Rh antigens and antibodies requires different reaction
conditions. ABO antibodies are naturally occurring IgM molecules and react best at
room temperature. Rh antibodies are generally immune IgG molecules that result from
transfusion or pregnancy. Detection may require 37°C incubation and/or enhancement
techniques

Question 43

7. Testing reveals a weak D that reacts 1+ after indirect antiglobulin testing (IAT). How is
   this result classified?
   A. Rh-positive
   B. Rh-negative, Du positive
   C. Rh-negative
   D. Rh-positive, Du positive
   Blood bank/Apply knowledge of standard operating procedures/Components/Rh label/2

Answer 43

A Blood tested for weak D that shows 1+ reaction after IAT is classified as Rh positive.
The weak D designation is not noted in the reporting of the result.

Question 44

8. What is one possible genotype for a patient who develops anti-C antibody?
   A. R1r
   B. R1R1
   C. r’r
   D. rr
   Blood bank/Apply knowledge of fundamental biological characteristics/Rh typing/2

Answer 44

D Only rr (dce/dce) does not contain C antigen. A person will form alloantibodies only to
the antigens he or she lacks.

Question 45

9. A patient developed a combination of Rh antibodies: anti-C, anti-E, and anti-D. Can
   compatible blood be found for this patient?
   A. It is almost impossible to find blood lacking C, E, and D antigens
   B. rr blood could be used without causing a problem
   C. R0R0 may be used because it lacks all three antigens
   D. Although rare, ryr blood may be obtained from close relatives of the patient

Answer 45

B The genotype rr (dce/dce) lacks D, C, and E antigens and would be suitable for an
individual who has developed antibodies to all three antigens. This is the most
common Rh-negative genotype and is found in nearly 14% of blood donors who are
white.

Question 46

10. A patient tests positive for weak D but also appears to have anti-D in his serum. What
    may be the problem?
    A. Mixup of samples or testing error
    B. Most weak D individuals make anti-D
    C. The problem could be caused by a disease state
    D. A D mosaic may make antibodies to missing antigen parts
    Blood bank/Apply knowledge to identify sources of error/Rh antibodies/2

Answer 46

D The D antigen comprises different parts designated as a mosaic. If an individual lacks
parts of the antigen, he or she may make antibodies to the missing parts if exposed to
the whole D antigen

Question 47

11. Which offspring is not possible from a mother who is R1R2 and a father who is R1r?
    A. DcE/DcE
    B. Dce/DCe
    C. DcE/DCe
    D. Dce/dce

Answer 47

A DcE/DcE (R2R2) is not possible because R2 can be inherited only from the mother and
is not present in the father.

Question 48

12. Which weak D phenotypes necessitate Rh immune globulin (RhIg) prophylaxis?
    A. 1
    B. 2
    C. 3
    D. None of the above
    Blood bank/Apply knowledge of biological characteristics/Rh testing/3

Answer 48

D Weak D phenotypes 1, 2, and 3 (as well as 4) are not associated with formation of
anti-D negating RhIg prophylaxis. Weak D phenotypes 5, 11, 15, 19, and 20 would
require RhIg prophylaxis

Question 49

13. What antibodies could an R1R1 make if exposed to R2R2 blood?
    A. Anti-e and anti-C
    B. Anti-E and anti-c
    C. Anti-E and anti-C
    D. Anti-e and anti-c
    Blood bank/Apply knowledge of fundamental biological characteristics/Rh antibodies/2

Answer 49

B The R1R1 (DCe/DCe) individual does not have the E or c antigen, and could make
anti-E and anti-c antibodies when exposed to R2R2 cells (DcE/DcE).

Question 50

14. What does the genotype —/— represent in the Rh system?
    A. Rh negative
    B. D mosaic
    C. Rhnull
    D. Total Rh
    Blood bank/Evaluate laboratory data to make identifications/Rh system/Rh antigens/2

Answer 50

C A person who is Rhnull shows no Rh antigens on his or her RBCs. Loss of Rh antigens
is very unlikely to happen because Rh antigens are integral parts of the RBC
membrane. The Rhnull phenotype can result from either genetic suppression of the Rh
genes or inheritance of amorphic genes at the Rh locus.

Question 51

15. What techniques are necessary for weak D testing?
    A. Saline + 22°C incubation
    B. Albumin or LISS + 37°C incubation
    C. Saline + 37°C incubation
    D. 37°C incubation + IAT
    Blood bank/Apply knowledge of basic laboratory procedures/Rh system/2

Answer 51

D Weak D testing requires both 37°C incubation and the IAT procedure. Anti-D is an
IgG antibody, and attachment of the D antigen is optimized at warmer temperatures.
AHG in the IAT phase facilitates lattice formation by binding to the antigen–antibody
complexes

Question 52

16. A patient types as AB and appears to be Rh positive on slide typing. What additional
    tests should be performed for tube typing?
    A. Rh negative control
    B. Direct antiglobulin test
    C. Low-protein Rh antisera
    D. No additional testing is needed
    Blood bank/Evaluate laboratory data to verify test results/Rh system/2

Answer 52

A An Rh-negative control (patient cells in saline or 6% albumin) should be run if a
sample appears to be AB positive. The ABO test serves as the Rh control for other
ABO types.

Question 53

17. According to the Wiener nomenclature and/or genetic theory of Rh inheritance:
    A. There are three closely linked loci, each with a primary set of allelic genes
    B. The alleles are named R1, R2, R0, r, r’, r”, Rz, and ry
    C. There are multiple alleles at a single complex locus that determine each Rh antigen
    D. The antigens are named D, C, E, c, and e
    Blood bank/Apply knowledge of fundamental biological principles/Rh system/2

Answer 53

C Wiener proposed a single-locus theory for Rh, with multiple alleles determining
surface molecules that embody numerous antigens.

Question 54

18. The Wiener nomenclature for the E antigen is:
    A. hr’
    B. hrv’
    C. rh”
    D. Rh0
    Blood bank/Apply knowledge of fundamental biological principles/Rh typing/1

Answer 54

C The Wiener designation for the E antigen is rh”. The Wiener designation hr’ denotes
c, hr” denotes e, and Rh0 is D.

Question 55

19. A physician orders 2 units of leukocyte-reduced RBCs. The patient is a 55-year-old
    male with anemia. He types as an AB negative, and his antibody screen is negative.
    There is only 1 unit of AB negative in inventory. What is the next blood type that should
    be given?
    A. AB positive (patient is male)
    B. A negative
    C. B negative
    D. O negative
    Blood bank/Evaluate sources of errors/Rh systems/3

Answer 55

B Although giving Rh-positive RBCs to an Rh-negative patient would not harm the
patient in this case, because he is male, giving A negative would be the first choice.
You should not expose a patient to the D antigen, if possible, and the residual anti-B in
a unit of A-negative packed cells is less immunogenic than giving B or O RBCs.

Question 56

20. Which technology may report an Rh-weak D positive as Rh negative?
    A. Gel system
    B. Solid phase
    C. Tube testing
    D. None of these options
    Blood bank/Apply knowledge of laboratory procedures/Rh system/2

Answer 56

A The Gel system cannot detect a weak D phenotype because there is no washing phase
in the Gel system.

Question 57

1. A patient has the Lewis phenotype Le(a-b-). An antibody panel reveals the presence of
   anti-Lea. Another patient with the phenotype Le(a-b+) has a positive antibody screen;
   however, a panel reveals no conclusive antibody. Should anti-Lea be considered a
   possibility for the patient with the Le(a-b+) phenotype?
   A. Anti-Lea should be considered as a possible antibody
   B. Anti-Lea may be a possible antibody, but further studies are needed
   C. Anti-Lea is not a likely antibody because even Leb individuals secrete some Lea
   D. Anti-Lea may be found in saliva but not detectable in serum
   Blood bank/Apply knowledge of fundamental biological characteristics/Blood groups/2

Answer 57

C Anti-Lea is produced primarily by persons with the Le(a-b-) phenotype because Le(ab+)
persons still have some Lea antigen present in saliva. Although Lea is not present
on their RBCs, Le(a-b+) persons do not form anti-Lea.

Question 58

2. A medical laboratory scientist (MLS) is having great difficulty resolving an antibody
   mixture. One of the antibodies is anti-Lea. This antibody is not clinically significant in
   this situation, but it needs to be removed to reveal the possible presence of an underlying
   antibody of clinical significance. What can be done?
   A. Perform an enzyme panel
   B. Neutralize the serum with saliva
   C. Neutralize the serum with hydatid cyst fluid
   D. Use dithiothreitol (DTT) to treat the panel cells
   Blood bank/Apply knowledge of fundamental biological characteristics/Blood groups/3

Answer 58

B Saliva from an individual with the Le gene contains the Lea antigen. This combines
with anti-Lea, neutralizing the antibody. Panel cells treated with DTT (0.2M) lose
reactivity with anti-K and other antibodies, but not anti-Lea. Hydatid cyst fluid
neutralizes anti-P1.

Question 59

3. What type of blood should be given to an individual who has anti-Leb that reacts 1+ at
   the IAT phase?
   A. Blood that is negative for Leb antigen
   B. Blood that is negative for both Lea and Leb antigens
   C. Blood that is positive for Leb antigen
   D. Lewis antibodies are not clinically significant, so any type of blood may be given
   Blood bank/Apply knowledge of fundamental biological characteristics/Blood group
   antibodies/3

Answer 59

A Lewis antibodies are generally not considered clinically significant unless they react at
37°C or at the IAT phase. The antibody must be honored in this scenario due to its
reactivity at the IAT phase of testing.

Question 60

4. Which of the following statements is true concerning the MN genotype?
   A. Antigens are destroyed using bleach-treated cells
   B. Dosage effect may be seen for both M and N antigens
   C. Both M and N antigens are impossible to detect because of cross-interference
   D. MN is a rare phenotype seldom found in routine antigen typing
   Blood bank/Apply knowledge of fundamental biological characteristics/Blood groups/2

Answer 60

B Dosage effect is the term used to describe the phenomenon of an antibody that reacts
more strongly with homozygous cells than with heterozygous cells. Dosage effect is a
characteristic of the genotype MN because the M and N antigens are both present on
the same cell. This causes a weaker reaction than seen with RBCs of either the MM or
NN genotype, which carry a greater amount of the corresponding antigen.

Question 61

5. Anti-M is sometimes found with reactivity detected at the immediate spin (IS) phase that
   persists in strength to the IAT phase. What is the main testing problem with a strong
   anti-M?
   A. Anti-M may not allow detection of a clinically significant antibody
   B. Compatible blood may not be found for the patient with a strongly reacting anti-M
   C. Anti-M cannot be removed from serum
   D. Anti-M may react with the patient’s own cells, causing a positive autocontrol
   Blood bank/Apply knowledge of fundamental biological characteristics/Blood groups/2

Answer 61

A Although anti-M may not be clinically significant, a strongly reacting anti-M that
persists through to the IAT phase may interfere with detection of a clinically
significant antibody that reacts only at IAT.

Question 62

6. A patient is suspected of having paroxysmal cold hemoglobinuria (PCH). Which pattern
   of reactivity is characteristic of the Donath-Landsteiner antibody, which causes this
   condition?
   A. The antibody attaches to RBCs at 4°C and causes hemolysis at 37°C
   B. The antibody attaches to RBCs at 37°C and causes agglutination at the IAT phase
   C. The antibody attaches to RBCs at 22°C and causes hemolysis at 37°C
   D. The antibody attaches to RBCs and causes agglutination at the IAT phase
   Blood bank/Apply knowledge of fundamental biological characteristics/Blood group
   antibodies/1

Answer 62

A The Donath-Landsteiner antibody has anti-P specificity with biphasic activity. The
antibody attaches to RBCs at 4°C and then causes the RBCs to hemolyze when
warmed to 37°C.

Question 63

7. How can interfering anti-P1 antibody be removed from a mixture of antibodies?
   A. Neutralization with saliva
   B. Agglutination with human milk
   C. Combination with urine
   D. Neutralization with hydatid cyst fluid
   Blood bank/Apply principles of special procedures/Blood group antibodies/1

Answer 63

D Hydatid cyst fluid contains P1 substance, which can neutralize anti-P1 antibody.

Question 64

8. Which antibody is frequently seen in patients with warm autoimmune hemolytic anemia
   (WAIHA)?
   A. Anti-Jka
   B. Anti-e
   C. Anti-K
   D. Anti-Fyb
   Blood bank/Apply knowledge of fundamental biological characteristics/Blood group
   antibodies/2

Answer 64

B Anti-e is frequently implicated in cases of WAIHA.
The corresponding antigen is characterized as high frequency in the Rh system and can
mask the presence of other alloantibodies.

Question 65

9. A patient’s antibody shows strong reactions in all test phases. All screen and panel cells
   are positive. Serum is then tested with a cord blood cell, and the reaction is negative.
   What antibody is suspected?
   A. Anti-I
   B. Anti-i
   C. Anti-H
   D. Anti-p
   Blood bank/Apply principles of special procedures/Antibody ID/2

Answer 65

A Adult cells contain mostly I antigen, and anti-I would react with all adult cells found
on screen or panel cells. Cord blood cells, however, contain mostly i antigen and
would test negative or only weakly positive with anti-I.

Question 66

10. Which group of antibodies is commonly found as cold agglutinins?
    A. Anti-K, anti-k, anti-Jsb
    B. Anti-D, anti-e, anti-C
    C. Anti-M, anti-N
    D. Anti-Fya, anti-Fyb
    Blood bank/Apply knowledge of fundamental biological characteristics/Blood group
    antibodies/1

Answer 66

C Antibodies to the M and N antigens are IgM antibodies commonly found as cold
agglutinins.

Question 67

11. Which of the following antibodies characteristically gives a refractile mixed-field
    appearance?
    A. Anti-K
    B. Anti-Dia
    C. Anti-Sda
    D. Anti-s
    Blood bank/Apply knowledge of fundamental biological characteristics/Blood group
    antibodies/1

Answer 67

C Anti-Sda characteristically gives a refractile mixed-field agglutination reaction in the
IAT phase. The refractile characteristic is more evident under the microscope.

Question 68

12. What does the 3+3 rule ascertain?
    A. An antibody is ruled in
    B. An antibody is ruled out
    C. 95% confidence that the correct antibody has been identified
    D. 95% confidence that the correct antibody has not been identified
    Blood bank/Apply principles of basic laboratory procedures/Antibody ID/1

Answer 68

C The 3+3 rule ascertains correct identification of antibody at a confidence level of
95%. For this level to be met, reagent RBCs are found containing target antigen to
suspected antibody that react in test phase; likewise, reagent RBCs devoid of antigen will not react in test phase.

Question 68

13. The k (Cellano) antigen is a high-frequency antigen and is found on most RBCs. How
    often would one expect to find the corresponding antibody?
    A. Often, because it is a high-frequency antibody
    B. Rarely, because most individuals have the antigen and therefore would not develop the
    antibody
    C. Depends on the population, because certain racial and ethnic groups show a higher
    frequency of anti-k
    D. Impossible to determine without consulting regional blood group antigen charts
    Blood bank/Calculate/Hemotherapy/1

Answer 68

B k antigen is found with a frequency of 99.8%; therefore, k-negative individuals are
rare. Because of this, the occurrence of anti-k is also rare.

Question 69

14. Which procedure would help to distinguish between anti-e and anti-Fya in an antibody
    mixture?
    A. Lowering the pH of test serum
    B. Running an enzyme panel
    C. Using a thiol reagent
    D. Running an LISS panel
    Blood bank/Apply principles of special procedures/Antibody ID/2

Answer 69

B Enzyme-treated cells will not react with Duffy antibodies. Rh antibodies react more
strongly with enzyme-treated RBCs. An enzyme panel, therefore, would enhance
reactivity of anti-e and destroy reactivity to anti-Fya.

Question 70

15. Which characteristics are true of all three of the following antibodies: anti-Fya, anti-
    Jka, and anti-K?
    A. Detected at the IAT phase; may cause hemolytic disease of the fetus and newborn
    (HDFN) and hemolytic transfusion reactions
    B. Not detected with enzyme-treated cells
    C. Requires the IAT technique for detection; usually not associated with HDFN
    D. Enhanced reactivity with enzyme-treated cells; may cause severe hemolytic transfusion
    reactions
    Blood bank/Apply principles of special procedures/Antibody ID/2

Answer 70

A Anti-Fya, anti-Jka, and anti-K are usually detected at IAT and all may cause HDFN
and transfusion reactions that may be hemolytic. Reactivity with anti-Fya is lost with
enzyme-treated RBCs, but reactivity with anti-Jka is enhanced with enzyme-treated
cells. Reactivity with anti-K is unaffected by enzyme-treated cells.

Question 71

16. A patient is admitted to the hospital. Medical records indicate that the patient has a
    history of anti-Jka. When you performed the type and screen, the type was O positive,
    and the screen was negative. You should:
    A. Crossmatch using units negative for Jka antigen
    B. Crossmatch random units, since the antibody is not demonstrating
    C. Request a new sample
    D. Repeat the screen with enzyme-treated screening cells
    Blood bank/Apply principles of basic laboratory procedures/Antibody ID/3

Answer 71

A The Kidd antibodies are notorious for disappearing from serum, yielding a negative
result for the antibody screen. If a patient has a history of a Kidd antibody, blood must
be crossmatched using antigen-negative units. If the patient is transfused with the
corresponding antigen, an anamnestic response may occur with a subsequent hemolytic
transfusion reaction.

Question 72

17. An MLS performs an antibody study and finds 1+ and weak positive reactions for
    several of the panel cells. The reactions do not fit a pattern. Several selected panels and
    a patient phenotype do not reveal any additional information. Serum is diluted and
    retested, but the same reactions persist. What type of antibody may be causing these
    results?
    A. Antibody to a high-frequency antigen
    B. Antibody to a low-frequency antigen
    C. High titer low avidity (HTLA)
    D. Anti-human leukocyte antigen (anti-HLA)
    Blood bank/Evaluate laboratory data to make identifications/Antibody ID/3

Answer 72

C HTLA antibodies may persist in reaction strength, even when diluted. These
antibodies are directed against high-frequency antigens (e.g., Cha). They are not
clinically significant but, when present, are responsible for a high incidence of
incompatible crossmatches.

Question 73

18. An antibody is detected in a pregnant woman and is suspected of being the cause of
    fetal distress. The antibody reacts at the IAT phase but does not react with DTT-treated
    cells. This antibody causes in vitro hemolysis. What is the most likely antibody
    specificity?
    A. Anti-Lea
    B. Anti-Lua
    C. Anti-Lub
    D. Anti-Xga
    Blood bank/Evaluate laboratory data to make identifications/Antibody ID/3

Answer 73

C Of the antibodies listed, only Lub is detected in the IAT phase, causes in vitro
hemolysis, may cause HDFN, and does not react with DTT-treated cells.

Question 74

19. What sample is best for detecting complement-dependent antibodies?
    A. Plasma stored at 4°C for no longer than 24 hours
    B. Serum stored at 4°C for no longer than 48 hours
    C. Either serum or plasma stored at 20°C to 24°C no longer than 6 hours
    D. Serum heated at 56°C for 30 minutes
    Blood bank/Apply principles of basic laboratory procedures/Antibody ID/2

Answer 74

B Serum stored at 4°C for no longer than 48 hours preserves complement activity.
Plasma is inappropriate because most anticoagulants chelate calcium needed for
activation of complement. Heating the serum to 56°C destroys complement.

Question 75

20. Which antibody would not be detected by group O screening cells?
    A. Anti-N
    B. Anti-A1
    C. Anti-Dia
    D. Anti-k
    Blood bank/Apply principles of special procedures/Antibody ID/1

Answer 75

B ABO antibodies are not detected by group O screening cells because O cells contain
no A or B antigens.

Question 76

21. Refer to Panel 1. Which antibody is most likely implicated?
    A. Anti-Fyb
    B. Anti-Jkb
    C. Anti-e
    D. Anti-c and anti-K
    Blood bank/Apply principles of special procedures/Antibody ID/2

Answer 76

B The pattern clearly fits that of anti-Jkb, an antibody that usually reacts best at IAT.
The weaker reactions are caused by the dosage effect found on cells that are
heterozygous for the Jkb antigen.

Question 77

1. SITUATION: An emergency trauma patient requires transfusion. Six units of blood are
   ordered stat (immediately). There is no time to draw a patient sample. O-negative blood
   is issued. When will compatibility testing be performed?
   A. Compatibility testing must be performed before blood is issued
   B. Compatibility testing will be performed when a patient sample is available
   C. Compatibility testing may be performed immediately by using donor serum
   D. Compatibility testing is not necessary when blood is issued in emergency situations
   Blood bank/Apply knowledge of laboratory operations/Crossmatch/3

Answer 77

B When patient serum is available, it will be crossmatched with donor cells. Patient
serum might contain antibodies against antigens on donor cells that may destroy donor
cells. If an incompatibility is discovered, the problem will be reported immediately to
the patient’s physician.

Question 78

2. How would autoantibodies affect compatibility testing?
   A. No effect
   B. The DAT result would be positive
   C. ABO, Rh, antibody screen, and crossmatching may show abnormal results
   D. Results would depend on the specificity of autoantibody
   Blood bank/Evaluate laboratory data to make identifications/Antibody ID/3

Answer 78

C Autoantibodies may cause positive reactions with screening cells, panel cells, donor
cells, and patient cells. The DAT result will be positive; however, DAT is not included
in compatibility testing.

Question 79

3. An antibody screen is reactive at the IAT phase of testing with all three cells of a threecell
   screen, and the autocontrol is negative. What is a possible explanation for these
   results?
   A. A cold alloantibody
   B. High-frequency alloantibody or a mixture of alloantibodies
   C. A warm autoantibody
   D. A cold and warm alloantibody
   Blood bank/Evaluate laboratory data to make identifications/Antibody ID/3

Answer 79

B High-frequency alloantibodies or a mixture of alloantibodies may cause all three
screening cells to be positive. A negative autocontrol would rule out autoantibodies

Question 80

4. What does a minor crossmatch consist of?
   A. Recipient plasma and recipient RBCs
   B. Recipient plasma and donor RBCs
   C. Recipient RBCs and donor plasma
   D. Donor plasma and donor RBCs
   Blood bank/Apply knowledge of laboratory operations/Crossmatch/1

Answer 80

C A minor crossmatch consists of recipient RBCs and donor serum or plasma.

Question 81

5. Can crossmatching be performed on October 14 using a patient sample drawn on
   October 12?
   A. Yes, a new sample would not be needed
   B. Yes, but only if the previous sample has no alloantibodies
   C. No, a new sample is needed because the 2-day limit has expired
   D. No, a new sample is needed for each testing
   Blood bank/Apply knowledge of standard operating procedures/Crossmatch/2

Answer 81

A Compatibility testing may be performed on a patient sample within 3 days of the
scheduled transfusion; however, if the patient is pregnant or was transfused within 3
months, the sample must be less than 3 days old.

Question 82

6. A type and screen was performed on a 32-year-old woman, and the patient was typed as
   AB negative. There are no AB-negative units in the blood bank. What should be done?
   A. Order AB-negative units from a blood supplier
   B. Check inventory of A-, B-, and O-negative units
   C. Ask the patient to make a preoperative autologous donation
   D. Nothing—the blood will probably not be used
   Blood bank/Apply principles of basic laboratory procedures/Crossmatch/2

Answer 82

B An AB person is the universal recipient and may receive any blood type; because only
a type and screen were ordered and blood may not be used, check inventory for A-, B-,
and O-negative units.

Question 82

7. What ABO types may donate to any other ABO type?
   A. A negative, B negative, AB negative, O negative
   B. O negative
   C. AB negative
   D. AB negative, A negative, B negative

Answer 82

B An O-negative individual has no A or B antigens and may donate RBCs to any other
ABO type.

Question 83

8. What type(s) of RBC(s) is (are) acceptable to transfuse to an O-negative patient?
   A. A negative, B negative, AB negative, or O negative
   B. O negative
   C. AB negative
   D. AB negative, A negative, B negative
   Blood bank/Apply knowledge of fundamental biological characteristics/Crossmatch/2

Answer 83

B An O-negative individual has both anti-A and anti-B and may receive only O-negative
RBCs.

Question 84

9. An MLS removed 4 units of blood from the blood bank refrigerator and placed them on
   the counter. A clerk was waiting to take the units for transfusion. As she checked the
   paperwork, she noticed that one of the units was leaking onto the counter. What should
   she do?
   A. Issue the unit if the RBCs appear normal
   B. Reseal the unit
   C. Discard the unit
   D. Call the medical director and ask for an opinion
   Blood bank/Apply knowledge of standard operating procedures/Crossmatch/3

Answer 84

C Leaking may indicate a broken seal or a puncture, which indicates possible
contamination of the unit, even if the RBCs appear normal. The unit should be
discarded

Question 85

10. A donor was found to contain anti-K using pilot tubes from the collection procedure.
    How would this affect the compatibility test?
    A. The AHG major crossmatch would be positive
    B. The IS major crossmatch would be positive
    C. The recipient’s antibody screen would be positive for anti-K
    D. Compatibility testing would not be affected
    Blood bank/Apply principles of basic laboratory procedures/Crossmatch/2

Answer 85

D Compatibility testing would not be affected if the donor has anti-K in his or her
serum. This is because the major crossmatch uses recipient serum and not donor
serum. Other tests, such as ABO, Rh, and antibody screen on the recipient, also would
not be affected

Question 86

11. Which of the following is not a requirement for electronic crossmatching?
    A. The computer system contains logic to prevent assignment and release of ABOincompatible
    blood
    B. There are concordant results of at least two determinations of the recipient’s ABO type on
    record, one of which is from the current sample
    C. Critical elements of the system have been validated on site
    D. There are concordant results of at least one determination of the recipient’s ABO type on
    file
    Blood bank/Apply principles of basic laboratory procedures/Crossmatch/1

Answer 86

D ABO determinations must be concordant on at least two occasions, including the
current sample.

Question 87

12. A patient showed positive results with screening cells and 4 donor units. The patient
    autocontrol was negative. What is the most likely antibody?
    A. Anti-H
    B. Anti-S
    C. Anti-Kpa
    D. Anti-k
    Blood bank/Evaluate laboratory data to make identifications/Incompatible crossmatch/3

Answer 87

D Anti-k (Cellano) is a high-frequency alloantibody that would react with screening
cells and most donor units. The negative autocontrol rules out autoantibodies. Anti-H
and anti-S are cold antibodies and anti-Kpa is a low-frequency alloantibody

Question 88

13. Screening cells and major crossmatch are positive on IS only, and the autocontrol is
    negative. Identify the problem.
    A. Cold alloantibody
    B. Cold autoantibody
    C. Abnormal protein
    D. Antibody mixture
    Blood bank/Evaluate laboratory data to make identifications/Incompatible crossmatch/3

Answer 88

A A cold alloantibody would show a reaction with screening cells and donor units only
at the IS phase. The negative autocontrol rules out autoantibodies and abnormal
protein.

Question 89

14. Six units are crossmatched. Five units are compatible, one unit is incompatible, and the
    recipient’s antibody screen is negative. Identify the problem:
    A. Patient may have an alloantibody to a high-frequency antigen
    B. Patient may have an abnormal protein
    C. Donor unit may have a positive DAT
    D. Donor may have a high-frequency antigen
    Blood bank/Evaluate laboratory data to make identifications/Incompatible crossmatch/3

Answer 89

C The incompatible donor unit may have an antibody coating the RBCs, or the patient
may have an alloantibody to a low-frequency antigen. An alloantibody to a highfrequency
antigen would agglutinate all units and screening cells.

Question 90

15. An incompatible donor unit is found to have a positive result on DAT. What should be
    done with the donor unit?
    A. Discard the unit
    B. Antigen type the unit for high-frequency antigens
    C. Wash the donor cells and use the washed cells for testing
    D. Perform a panel on the incompatible unit
    Blood bank/Apply principles of special procedures/Incompatible crossmatch/3

Answer 90

A The incompatible unit may have RBCs coated with antibody and/or complement. If
RBCs are sensitized, then some problem exists with the donor. Discard the unit.

Question 91

16. Screening cells, major crossmatch, and patient autocontrol are positive in all phases.
    Identify the problem.
    A. Specific cold alloantibody
    B. Specific cold autoantibody
    C. Abnormal protein or nonspecific autoantibody
    D. Cold and warm alloantibody mixture
    Blood bank/Evaluate laboratory data to make identifications/Incompatible crossmatch/3

Answer 91

C An abnormal protein or nonspecific autoantibody would cause antibody screen,
crossmatch, and patient autocontrol to be positive. Alloantibodies would not cause a
positive patient autocontrol

Question 92

17. A panel study has revealed the presence of patient alloantibodies. What is the first step
    in a major crossmatch?
    A. Perform a DAT on patient cells and donor units
    B. Antigen type patient cells and any donor cells to be crossmatched
    C. Adsorb any antibodies from patient serum
    D. Obtain a different enhancement medium for testing
    Blood bank/Apply principles of special procedures/Incompatible crossmatch/2

Answer 92

B Antigen typing or phenotyping of the patient’s cells confirms the antibody
identification; antigen typing of donor cells helps ensure the crossmatch of compatible
donor units

Question 93

18. What is the disposition of a donor RBC unit that contains an antibody?
    A. The unit must be discarded
    B. Only the plasma may be used to make components
    C. The antibody must be adsorbed from the unit
    D. The unit may be labeled to indicate that it contains antibody and released into inventory
    Blood bank/Apply knowledge of laboratory operations/Hemotherapy/Blood components/1

Answer 93

D The unit may be used in the general blood inventory, if it is properly labeled and only
cellular elements are used.

Question 94

19. Given a situation where screening cells, major crossmatch, autocontrol, and DAT (anti-
    IgG) are all positive, what procedure should be performed next?
    A. Adsorption using rabbit stroma
    B. Antigen typing of patient cells
    C. Elution followed by a cell panel on the eluate
    D. Selected cell panel

Answer 94

C A positive DAT using anti-IgG indicates that antibodies are coating the patient’s
cells. An eluate would be helpful to remove the antibody, followed by a cell panel to
identify it.

Question 95

20. A major crossmatch and screening cells are 2+ at the IS phase, 1+ at 37°C, and negative
    at the IAT phase. Identify the most likely problem.
    A. Combination of antibodies
    B. Cold alloantibody
    C. Rouleaux
    D. Test error
    Blood bank/Evaluate laboratory data to make identifications/Incompatible crossmatch/3

Answer 95

B The reaction pattern fits that of a cold antibody reacting at the IS phase and of
sufficient titer to persist at 37°C incubation. The reactions disappear in the IAT phase.

Question 96

21. What corrective action should be taken when rouleaux causes positive test results?
    A. Perform a saline replacement technique
    B. Perform an autoabsorption
    C. Run a panel
    D. Perform an elution
    Blood bank/Apply principles of special procedures/Testing problems/3

Answer 96

A Rouleaux may be dispersed or lessened by using the saline replacement technique.
This involves recentrifuging the tube, then withdrawing serum and replacing it with
two drops of saline. The tube is respun and examined for hemolysis.

Question 97

22. All of the following are reasons for performing an adsorption, except:
    A. Separation of mixtures of antibodies
    B. Removal of interfering substances
    C. Confirmation of weak antigens on RBCs
    D. Identification of antibodies causing a positive DAT
    Blood bank/Apply principles of special procedures/Antibody identification/2

Answer 97

D Antibodies causing a positive DAT would be coating RBCs and would require elution, not adsorption, to identify them.

Question 98

23. How long must a recipient sample be kept in the blood bank after compatibility testing?
    A. 3 days
    B. 5 days
    C. 7 days
    D. 10 days
    Blood bank/Apply principles of basic laboratory procedures/Compatibility/1

Answer 98

C According to the American Association of Blood Banks (AABB) standards, the
recipient sample must be kept for 7 days after compatibility testing.

Question 99

24. What is the crossmatching protocol for platelets and/or plasma?
    A. Perform a reverse grouping on donor plasma
    B. No testing is required
    C. Perform a reverse grouping on recipient plasma
    D. Platelets must be HLA compatible
    Blood bank/Apply principles of basic laboratory procedures/Compatibility/2

Answer 99

B For transfusion of platelets and plasma, there is no required protocol for
crossmatching.

Question 100

25. What are the compatibility requirements for an autologous unit?
    A. ABO and Rh typing
    B. Type and screen
    C. Major crossmatch
    D. All of these options
    Blood bank/Apply principles of basic laboratory procedures/Compatibility/1

Answer 100

A The only requirement for transfusing an autologous unit is a check of the ABO and
Rh types.

Question 101

26. A patient is typed as AB positive. Two units of blood have been ordered by the
    physician. Currently, the inventory shows no AB units, 10 A-positive units, 1 A-negative
    unit, 5 B-positive units, and 20 O-positive units. Which should be set up for the major
    crossmatch?
    A. A-positive units
    B. O-positive units
    C. B-positive units
    D. Call another blood supplier for type-specific blood
    Blood bank/Apply principles of basic laboratory procedures/Compatibility/2

Answer 101

A The type chosen should be A-positive RBC units. Although all choices would be
compatible, the first choice should be A-positive because this unit will contain residual
plasma anti-B. Anti-B is less immunogenic than anti-A, which would be present, albeit
in small amounts, in B-positive and O-positive units.

Question 102

27. Which of the following comprises an abbreviated crossmatch?
    A. ABO, Rh, and antibody screen
    B. ABO, Rh, antibody screen, IS crossmatch
    C. Type and screen
    D. ABO, Rh, IS crossmatch
    Blood bank/Apply principles of basic laboratory procedures/Crossmatch/2

Answer 102

B The abbreviated crossmatch usually consists of a type and screen and an IS
crossmatch.

Question 103

28. When may IS crossmatching be performed?
    A. When a patient is being massively transfused
    B. When there is no history of antibodies and the current antibody screen is negative
    C. When blood is being emergency released
    D. When a patient has not been transfused in the past 3 months
    Blood bank/Apply principles of basic laboratory procedures/Crossmatch/1

Answer 103

B IS crossmatching may be performed when the patient has no history of antibodies and
the current antibody screen is negative.

Question 104

1. A patient had a transfusion reaction to packed RBCs. The MLS began the laboratory
   investigation of the transfusion reaction by assembling pre- and post-transfusion
   specimens and all paperwork and computer printouts. What should the MLS do next?
   A. Perform a DAT on the post-transfusion sample
   B. Check for clerical error(s)
   C. Repeat ABO and Rh typing of patient and donor units
   D. Perform an antibody screen on the post-transfusion sample
   Blood bank/Apply knowledge of standard operating procedures/Transfusion reactions/2

Answer 104

B Over 90% of transfusion reactions are caused by some type of clerical error. The most time-saving approach would be to check all paperwork before performing any
laboratory testing

Question 105

2. What is the pathophysiological cause surrounding anaphylactic and anaphylactoid
   reactions?
   A. Antibody in patient’s serum is detected 3 to 7 days after transfusion and is attached to
   donor RBCs
   B. Donor plasma has reagins (IgE or IgA) that combine with allergens in patient’s plasma
   C. Patient is deficient in IgE and develops IgE antibodies via sensitization as a result of
   transfusion or pregnancy
   D. Patient is deficient in IgA and develops IgA antibodies via sensitization as a result of
   transfusion or pregnancy
   Blood bank/Apply knowledge of fundamental biological principles/Transfusion reactions/1

Answer 105

D Anaphylactic or anaphylactoid reactions are the most severe form of allergic
transfusion reaction and are associated with deficient or absent IgA in the patients,
allowing the formation of anti-IgA. These patients must be transfused with washed
cellular products where the plasma has been removed.

Question 106

3. A patient has a hemolytic reaction to blood transfused 8 days ago. What is the most
   likely cause?
   A. Immediate, nonimmunologic, probably as a result of volume overload
   B. Delayed immunologic, probably as a result of an antibody such as anti-Jka
   C. Delayed nonimmunologic, probably as a result of iron overload
   D. Immediate, immunologic, probably as a result of clerical error, ABO incompatibility
   Blood bank/Apply knowledge of fundamental biological characteristics/Transfusion
   reactions/2

Answer 106

B A transfusion reaction that occurs several days after a transfusion of blood products is
probably a delayed immunologic reaction as a result of an antibody formed against
donor antigens. This is a classic example of a reaction caused by an antibody, such as
anti-Jka.

Question 107

4. What may be found in the serum of a person who is exhibiting signs of transfusionrelated
   acute lung injury (TRALI)?
   A. RBC alloantibody
   B. IgA antibody
   C. Antileukocyte antibody
   D. Allergen
   Blood bank

Answer 107

C TRALI is associated with antibodies to human leukocyte antigens or neutrophil
antigens, which react with the patient’s granulocytes and cause acute respiratory
insufficiency.

Question 108

5. Which type of transfusion reaction occurs in about 1% of all transfusions, results in a
   temperature rise of greater than 1°C above 37°C associated with blood component
   transfusion, and is not related to the patient’s medical condition?
   A. Immediate hemolytic
   B. Delayed hemolytic
   C. Febrile nonhemolytic reaction
   D. TRALI
   Blood bank/Apply knowledge of fundamental biological characteristics/Transfusion
   reactions/2

Answer 108

C FNHTR is defined as a rise in temperature of greater than 1°C above 37°C, associated
with transfusion and unexplained by other causes. The patient has formed antibodies to
HLA, which reacted with donor cells and resulted in release of pyrogens.

Question 109

6. What would be the result of group A blood given to a group O patient?
   A. Nonimmune transfusion reaction
   B. Immediate hemolytic transfusion reaction
   C. Delayed hemolytic transfusion reaction
   D. Febrile nonhemolytic transfusion reaction (FNHTR)
   Blood bank/Apply knowledge of fundamental biological characteristics/Transfusion
   reactions/2

Answer 109

B Group A blood given to a group O patient would cause an immediate hemolytic
transfusion reaction because a group O patient has anti-A and anti-B antibodies and
would destroy A cells.

Question 110

7. Patient DB received 2 units of group A-positive RBCs 2 days ago. Two days later, he
   developed a fever and appeared jaundiced. His blood type was A positive. A transfusion
   reaction workup was ordered. There were no clerical errors detected. A posttransfusion
   specimen was collected and a DAT performed. The DAT result was positive
   with monospecific anti-IgG. The plasma was also hemolyzed. An antibody screen and
   panel studies revealed the presence of anti-Jkb in the post-transfusion specimen. The
   antibody screen on the pretransfusion specimen was negative. Which of the following
   explains the positive DAT?
   A. The donor cells had a positive DAT
   B. The donor cells were polyagglutinable
   C. The donor cells were likely positive for the Jkb antigen
   D. The recipient cells were likely positive for the Jkb antigen
   Blood bank/Apply knowledge of fundamental biological characteristics/Transfusion
   reactions/3

Answer 110

C This is an example of an anamnestic reaction, where the patient was most likely
exposed to the Jkb antigen at some point in his life, and upon re-exposure to the
antigen, the antibody titer rose to detectable levels. This resulted in positive DAT and
post-transfusion antibody screen results.

Question 111

8. All of the following are part of the preliminary evaluation of a transfusion reaction, except:
   A. Check pre- and post-transfusion samples for color of serum
   B. Perform ABO and Rh recheck
   C. Perform DAT on the post-transfusion sample
   D. Perform a panel on pre- and post-transfusion samples
   Blood bank/Apply knowledge of standard operating procedures/Transfusion reactions/1

Answer 111

D The preliminary evaluation of a transfusion reaction includes checking the color of
serum and performing ABO and Rh checks and DAT on the post-transfusion sample.
A panel would not be part of the preliminary workup.

Question 112

9. A 68-year-old female diagnosed with neutropenia and inflammation of the left hand was
   typed as A positive and received 1 packed RBC unit. The antibody screen was negative,
   and crossmatch was compatible. During the transfusion, her pulse was 94, and blood
   pressure (BP) rose from 114/59 mm Hg to 132/64 mm Hg. Temperature rose from
   37.1°C before transfusion to 37.8°C 60 minutes after starting transfusion and then to
   38.3°C upon completion. A post-transfusion specimen yielded plasma that was neither
   hemolyzed nor icteric, and a negative DAT. Post-transfusion urinalysis showed 1+ blood
   and protein with 10 RBCs/high-power field (hpf) microscopically. The clerical check
   result was acceptable. What type of reaction most likely occurred as a result of
   transfusion?
   A. Allergic
   B. Circulatory overload
   C. Febrile nonhemolytic
   D. Delayed hemolytic
   Blood bank/Correlation of laboratory and clinical data/Transfusion reactions/3

Answer 112

C The temperature rose from 37.1°C to 38.3°C. The DAT result was negative, and
although blood was found on the urinalysis, microscopic RBCs were also found.
Because intact RBCs are not caused by a transfusion reaction, the cause of hematuria
was not likely transfusion related. A febrile nonhemolytic reaction is highly consistent
with both symptoms and post-transfusion test results.

Question 113

10. A 92-year-old male diagnosed with anemia and episodes of frequent falling was typed as B negative and transfused with 1 unit of packed RBCs, also B negative. He had not been
    recently transfused, and the antibody screen was negative. During the transfusion, his
    temperature rose from 36.2°C to 36.4°C, his pulse from 96 to 124, respirations from 18
    to 20, and BP from 127/81 mm Hg to 174/83 mm Hg. He was transfused with 205 mL
    before a reaction was called by the transfusionist. The post-transfusion specimen DAT
    result was negative, and the clerical check result was acceptable. Urinalysis showed 1+
    blood with 5 RBCs microscopically. Other symptoms included tachycardia and
    flushing. What reaction had most likely taken place?
    A. Febrile nonhemolytic
    B. Acute hemolytic
    C. Anaphylactic
    D. Volume overload
    Blood bank/Correlation of laboratory and clinical data/Transfusion reaction/3

Answer 113

D The tachycardia, increased pulse, and volume transfused before a reaction was called
are consistent with volume overload. The temperature change did not meet criteria for
a febrile reaction, and evidence for a hemolytic reaction is lacking.

Question 114

11. A 76-year-old female diagnosed with urosepsis was transfused with 2 units of packed
    RBCs. Her type was AB positive and she had a negative result on antibody screen. The
    units transfused were AB positive. Upon receiving the second unit, the patient became
    hypoxic with tachypnea. The clerical check result was acceptable, and the DAT was
    negative. She received 269 mL from the second unit before a reaction was called. Her
    temperature fell from 38°C to 36.4°C, her pulse increased from 72 to 90, and
    respirations rose from 35 to 41. Her BP was 110/70 mm Hg. The patient died
    approximately 12 hours after the reaction was called. What type of reaction was most
    likely present?
    A. Febrile
    B. Symptoms not related to transfusion
    C. Allergic
    D. TRALI
    Blood bank/Correlate laboratory and clinical data/Transfusion reactions/3

Answer 114

B This case emphasizes the statistic that not all causes of death are related to
transfusion. The temperature dropped ruling out a febrile reaction; there was no
evidence of pulmonary edema or hypotension seen with TRALI (and plasma products
are more associated with TRALI compared with RBCs); and there was no sign of hives
or itching, which are often associated with an allergic reaction

Question 115

12. A 52-year-old male received 2 units of packed RBCs as an outpatient in the intravenous
    (IV) therapy unit. He had had a head trauma 20 years ago and was quadriplegic. He
    had recurrent pneumonia and hematuria as a result of removal of a Foley catheter. His
    blood type was A positive, with previously identified anti-Fya. There was an ABO
    discrepancy, in that reverse typing with reagent A1 cells was positive. The MLS
    attributed this reaction to Fya antigen being present on the reagent A1 cells. The patient
    also had a cold autoantibody. Two units of A-positive packed cells were crossmatched
    that were Fya negative and were compatible. One unit was transfused at 11:30 a.m.
    without incident. The second unit was transfused at 2:16 p.m. and stopped at 3:55 p.m.
    because of reddish brown–tinged urine found in his collection bag. A post-transfusion
    specimen yielded a positive DAT and plasma that was grossly hemolyzed. A prewarm
    crossmatch was incompatible in both the pre- and post-transfusion specimens. Anti-E
    and anti-c were present in the post-transfusion specimen. What reaction was most likely
    present?
    A. Acute hemolytic
    B. Febrile
    C. Allergic
    D. TRALI
    Blood bank/Correlate laboratory and clinical data/Transfusion reactions/3

Answer 115

A This case represents an acute hemolytic reaction where the patient had previous
sensitization to E and c antigens. Given the history of anti-Fya, an assumption was
made that anti-Fya was the cause of the positive reverse type with A1 cells, even
though this antibody does not react at the IS phase. This brings to light the importance
of running a panel whenever the patient has a positive antibody screen, regardless of
previous results. Hemoglobinuria, a positive DAT, and the hemolyzed post-transfusion
specimen all are consistent with an acute hemolytic reaction.

Question 116

13. An 82-year-old male was admitted for renal failure. His type was B positive, and his
    antibody screen was negative. Two units of RBCs were ordered. The first unit was
    transfused at 1:00 p.m. without incident. The second was started at 4:15 p.m. and
    stopped at 5:12 p.m. after the nurse observed that the patient had died. Vital signs had
    been taken at 4:30 p.m. with no abnormalities. A transfusion reaction was called and
    the blood unit, tubing, and paperwork sent to the blood bank. There were no clinical
    manifestations noted on the paperwork, and no post-transfusion specimen was sent to
    the blood bank. What type of reaction most likely occurred?
    A. Cause not related to transfusion
    B. Acute hemolytic reaction
    C. Anaphylactic reaction
    D. Volume overload
    Blood bank/Correlate clinical and laboratory data/Transfusion reactions/3

Answer 116

A This example represents a situation where the pathologist was not provided with all
information needed to interpret the reaction. There was no information on patient
symptoms, the patient had received another unit of RBCs hours previously with no
problems, and a postreaction specimen was not collected. Therefore, any serological
abnormalities could not be identified. The U.S. Food and Drug Administration (FDA)
recommends collecting a postmortem specimen if a reaction is called so that the
investigation of transfusion reaction can be completed. In this case, the pathologist
interpreted the reaction as not related to transfusion because no symptoms were
documented.

Question 117

1. A male patient with cancer was admitted to the hospital with acute abdominal pain and
   a hemoglobin level of 6 g/dL. Small bowel resection was indicated, but the attending
   physician wanted to raise the patient’s hemoglobin level to 12 g/dL before surgery. How
   many units of RBCs would most likely be required to accomplish this?
   A. 2
   B. 3
   C. 6
   D. 8
   Blood bank/Apply knowledge of fundamental biological characteristics/Blood
   components/RBCs/2

Answer 117

C One unit of RBCs will raise the hemoglobin level by approximately 1.0 to 1.5 g/dL,
and the hematocrit by 3% to 4%. Results vary, depending on the age of the blood and
the patient’s blood volume and hydration status. Six units will raise the hemoglobin
level to at least 12 g/dL.

Question 118

2. Which of the following is not a viable method for removing leukocytes from RBCs?
   A. Prestorage filtration
   B. Bedside filtration
   C. Poststorage filtration
   D. Buffy coat removal
   Blood bank/Apply knowledge of fundamental biological characteristics/Blood
   components/RBCs/1

Answer 118

D Removal of the buffy coat, which contains both platelets and white blood cells
(WBCs), is not an approved method for leukocyte reduction of RBCs. The other
methods can be employed to achieve a leukocyte reduction of less than 5 × 106.

Question 119

3. Four units of packed RBCs were brought to the nurses’ station at 10:20 a.m. Two units
   were transfused immediately, and 1 unit was transfused at 10:40 a.m. The remaining
   unit was returned to the blood bank at 11:00 a.m. The units were not refrigerated after
   leaving the blood bank. What problem(s) is (are) present in this situation?
   A. The only problem is with the returned unit; the 30-minute limit has expired and the unit
   cannot be used
   B. The unit should not have been transfused at 10:40 a.m. because the time limit had expired;
   this unit and the remaining unit should have been returned to the blood bank
   C. The returned unit may be held for this patient for 48 hours but cannot be used for another
   patient
   D. No problems; all actions were performed within the allowable time limits
   Blood bank/Select course of action/Blood components/RBCs/3

Answer 119

A There is a 30-minute time limit for a unit of RBCs that is not kept under proper storage
conditions (1°C–6°C).

Question 120

4. A unit of whole blood is collected at 10:00 a.m. and stored at 20°C to 24°C. What is the
   last hour at which platelet concentrates may be made from this unit?
   A. 4:00 p.m.
   B. 6:00 p.m.
   C. 7:00 p.m.
   D. 8:00 p.m.
   Blood bank/Apply knowledge of standard operating procedures/Blood components/3

Answer 120

B Platelet preparation from whole blood must be done within 8 hours of collection.

Question 121

5. Which of the following is acceptable according to the AABB standards?
   A. Rejuvenated RBCs may be made within 3 days of outdate and transfused or frozen within
   24 hours of rejuvenation
   B. Frozen RBCs must be prepared within 30 minutes of collection and may be used within 10
   years
   C. Irradiated RBCs must be treated within 8 hours of collection and transfused within 6 hours
   D. Leukocyte-reduced RBCs must be prepared within 6 hours of collection and transfused
   within 6 hours of preparation
   Blood bank/Apply knowledge of laboratory operations/Blood components/RBCs/2

Answer 121

A Rejuvenated RBCs may be prepared within 3 days of the outdate of the unit and
washed and transfused or frozen within 24 hours. A unit of RBCs may be frozen within
6 days of collection. An RBC unit can be irradiated any time prior to the expiration
date; once irradiated, the unit must be transfused within 28 days of irradiation or the
original outdate, whichever comes first. Leukocyte-reduced RBCs should be prepared
within 6 hours of collection, but must be given within 24 hours, if prepared using an
open system. Leukocyte-reduced RBCs prepared using a closed system may be kept
until the original date of expiration.

Question 122

6. Which of the following is true regarding apheresis platelets?
   A. The minimum platelet count must be 3.0 × 1011, pH must be 6.0 or greater
   B. The minimum platelet count must be 3.0 × 1010, pH must be 6.2 or less
   C. The minimum platelet count must be 3.0 × 1011, pH must be 6.2 or greater
   D. The minimum platelet count must be 5.5 × 1010, pH must be 6.0 or less
   Blood bank/Apply knowledge of laboratory operations/Blood components/Platelets/1

Answer 122

C Single-donor platelets prepared by apheresis must contain a minimum of 3.0 × 1011
platelets, and pH must be 6.2 or higher throughout the shelf life of the product.

Question 123

7. What is the component of choice for a patient with chronic granulomatous disease
   (CGD)?
   A. Fresh frozen plasma (FFP)
   B. Granulocytes
   C. Cryoprecipitate
   D. RBCs
   Blood bank/Apply knowledge of laboratory operations/Blood components/3

Answer 123

B Patients with CGD cannot fight bacterial infections because of dysfunctional
phagocytic enzymes; granulocyte concentrates are the product of choice for these
patients

Question 124

8. What method can be employed to detect bacteria in random donor platelets?
   A. pH
   B. Glucose
   C. Pan-genera detection (PGD) assay
   D. Gram stain
   Blood bank/Apply knowledge of laboratory operations/Blood components/Preparation of
   components/1

Answer 124

C The FDA has mandated that pH and glucose can no longer be used as a screening test
for platelets. The Verax PGD assay has been FDA approved for both single-donor
platelets and random-donor platelets for bacteria screening.

Question 125

9. All of the following statements regarding FFP are true, except:
   A. FFP must be prepared within 24 hours of collection
   B. After thawing, FFP must be transfused within 24 hours
   C. Storage temperature for FFP with a 1-year shelf life is –18°C or less
   D. When thawed, FFP must be stored between 1°C to 6°C
   Blood bank/Apply knowledge of standard operating procedures/Blood components/RBCs/1

Answer 125

A FFP must be prepared within 8 hours after collection or according to FDA-cleared
operator manual/inserts.

Question 126

10. What may be done to RBCs before transfusion to a patient with cold agglutinin disease
    to reduce the possibility of a transfusion reaction?
    A. Irradiate to prevent graft-versus-host-disease (GVHD)
    B. Wash with 0.9% saline
    C. Warm to 37°C with a blood warmer
    D. Transport so that temperature is maintained at 20°C to 24°C
    Blood bank/Apply knowledge of standard operating procedures/Hemotherapy/RBCs/2

Answer 126

C A patient having cold agglutinins might have a reaction to a cold blood product. The
product should be warmed to 37°C before transfusion.

Question 127

11. A unit of packed RBCs is split using the open system. One of the half units is used.
    What may be done with the second half unit?
    A. Must be issued within 24 hours
    B. Must be issued within 48 hours
    C. Must be irradiated
    D. Must retain the original expiration date
    Blood bank/Apply knowledge of laboratory operations/Blood components/RBCs/2

Answer 127

A The other half unit must be issued within 24 hours, if an open system is used to split
the unit

Question 128

12. What should be done if a noticeable clot is found in an RBC unit?
    A. Issue the unit; the blood will be filtered
    B. Issue the unit; note the presence of a clot on the release form
    C. Filter the unit in the blood bank before issue
    D. Do not issue the unit
    Blood bank/Select course of action/Hemotherapy/RBCs/2

Answer 128

D A unit having a noticeable clot should not be issued for transfusion to a patient. The
clot may be an indication of contamination or bacterial growth

Question 129

13. Cryoprecipitate may be used to treat all of the following, except:
    A. von Willebrand disease
    B. Hypofibrinogenemia
    C. Idiopathic thrombocytopenic purpura (ITP)
    D. Factor XIII deficiency
    Blood bank/Select best course of action/Hemotherapy/Cryo/3

Answer 129

C Cryoprecipitate may be used to treat von Willebrand disease, hypofibrinogenemia, and factor XIII deficiency, but is not indicated in ITP. IVIG is the product of choice for
ITP.

Question 130

14. SITUATION: A transplant patient may receive only type A or AB platelets. Only type
    O apheresis platelets are available. What devices may be used to deplete the
    incompatible plasma and replace with sterile saline?
    A. Cytospin/irradiator
    B. Water bath/centrifuge
    C. Centrifuge/sterile connecting device
    D. Cell washer/heat sealer
    Blood bank/Apply knowledge of standard operating procedures/Blood
    components/Platelets/2

Answer 130

C In the event of an ABO-mismatched stem cell transplant, special attention must be
paid to the choice of transfused blood products. Type A or AB platelets may be given
to a transplant in which the donor is type A and the recipient is type O; once the stem
cells engraft, platelets/plasma must be compatible with type A cells. If only type O
single-donor platelets are available, the product can be spun down using a centrifuge
and plasma can be removed. Then, a sterile connecting device can be used to
aseptically transfer sterile isotonic saline to the platelet product, replacing the
incompatible plasma.

Question 131

15. What component(s) is (are) indicated for patients who have anti-IgA antibodies?
    A. Whole blood
    B. Packed RBCs
    C. Washed or deglycerolized RBCs
    D. Granulocytes
    Blood bank/Select course of action/Hemotherapy/2

Answer 131

C Patients with anti-IgA antibodies should not receive components containing plasma.
Washed or deglycerolized RBCs can be issued.

Question 132

16. What is the expiration date for pooled cryoprecipitate (pooled before freezing)?
    A. 12 months from latest date of collection of product in pool
    B. 12 months from earliest date of collection of product in pool
    C. 4 hours
    D. 6 hours
    Blood bank/Apply knowledge of standard operating procedures/Blood components/FFP/1

Answer 132

B Expiration of pooled cryoprecipitate must take into account that there may be units
that makeup the pool with differing collection dates where the earliest date is used to
determine the expiration date.

Question 133

17. All of the following are true regarding washed RBCs, except:
    A. RBCs are washed with 1 to 2 L of normal saline
    B. Volume is 180 mL
    C. Shelf life is extended
    D. Leukocytes are removed
    Blood bank/Apply knowledge of standard operating procedures/Blood
    components/Processing/1

Answer 133

C Washed RBCs renders the system “open” and shortens the expiration time to 24
hours.

Question 134

18. What is a special condition for the storage of platelets?
    A. Room temperature, 20°C to 24°C
    B. No other components may be stored with platelets
    C. Platelets must be stored upright in separate containers
    D. Platelets require constant agitation at 20°C to 24°C
    Blood bank/Apply knowledge of standard operating procedures/Blood
    components/Processing/1

Answer 134

D Platelets require constant agitation and are stored at temperatures between 20°C and
24°C. Cold-stored platelets (single donor [apheresis] platelets stored at 1-6°C for up to
3 days) may be used for actively bleeding patients, but are not approved for treating
thrombocytopenia.

Question 135

19. Transfusion of an irradiated product is indicated in all of the following conditions
    except:
    A. Exchange transfusion
    B. Bone marrow transplantation
    C. Severe combined immunodeficiency syndrome (SCIDS)
    D. Warm autoimmune hemolytic anemia
    Blood bank/Select course of action/Hemotherapy/Irradiation/2

Answer 135

D WAIHA would not require irradiation unless the patient had an underlying
immunosuppressive disorder

Question 136

20. What percentage of RBCs must be retained in leukocyte-reduced RBCs?
    A. 75%
    B. 80%
    C. 85%
    D. 100%

Answer 136

C An RBC unit that has been leukocyte reduced must retain 85% of original RBCs

Question 137

21. Which of the following is true regarding granulocyte concentrates?
    A. The product must contain a maximum of 1.0 × 1010 granulocytes
    B. pH must be 6.0
    C. The product must be crossmatched
    D. The product must be irradiated
    Blood bank/Apply knowledge of standard operating procedures/Blood components/2

Answer 137

C Granulocyte concentrates contain a large amount of RBCs (greater than 2 mL) that
must be crossmatched with the recipient’s serum.

Question 138

22. What course of action should be taken if an MLS inadvertently irradiates a unit of
    RBCs twice?
    A. Issue the unit
    B. Discard the unit
    C. Change the expiration date; then issue the unit
    D. Note on the irradiation sticker that the unit was irradiated twice, and then issue the unit
    Blood bank/Apply knowledge of standard operating procedures/Irradiation/2

Answer 138

B If an MLS mistakenly irradiates a unit of RBCs more than once, the unit must be
discarded because of subsequent potassium accumulation. This does not apply to
platelets.

Question 139

23. What components(s) may be shipped together with FFP?
    A. Frozen RBCs and cryoprecipitate
    B. Platelets
    C. Packed RBCs and granulocytes
    D. Double RBC units

Answer 139

A FFP requires dry ice for shipment. Frozen RBCs and cryoprecipitate also require dry
ice.

Question 140

24. A blood supplier ships 3 units of pooled cryoprecipitate. Each pool consists of 5 units of
    cryoprecipitate. If one unit is thawed at 5:00 p.m., when must it be dispensed from the
    blood bank?
    A. Before 9:00 p.m.
    B. Before 11:00 p.m.
    C. Before 12:00 a.m.
    D. Before 5:00 p.m. the next day

Answer 140

A A thawed unit of pooled cryoprecipitate must be dispensed within 4 hours unless a
sterile connecting device was used, which would extend expiration to 6 hours.

Question 141

How does irradiation prevent transfusion-associated graft-versus-host disease (TAGVHD)?
A. Gamma rays and x-rays destroy the lymphocytes’ ability to divide
B. X-rays cause lysis of the lymphocytes
C. Gamma rays enhance lymphocyte reactivity
D. Ultraviolet radiation induces apoptosis of lymphocytes
Blood bank/Apply knowledge of standard operating procedures/Blood components/Stem
cells/1

Answer 141

A Gamma rays or x-rays have the ability to prohibit a lymphocyte’s ability to divide,
preventing TA-GVHD.

Question 142

26. Which component has the longest expiration date?
    A. Cryoprecipitate
    B. FFP
    C. Frozen RBCs
    D. Platelet concentrates
    Blood bank/Apply knowledge of standard operating procedures/Blood bank/Expiration
    date/1

Answer 142

C Frozen RBCs may be kept for up to 10 years, or longer if the transfusion service or
blood center has a policy for extension beyond 10 years. FFP and cryoprecipitate
stored at –18°C or lower expire in 1 year. If FFP is kept at –65°C or lower, the
expiration time is 7 years. Platelet concentrates expire from 24 hours to 5 days,
depending on the collection system used.

Question 143

27. All of the following are advantages of using single-donor platelets as opposed to random
    donor platelets, except:
    A. Less preparation time
    B. Less antigen exposure for patients
    C. May be HLA matched
    D. No pooling is required
    Blood bank/Apply principles of special procedures/Blood components/Platelets/1

Answer 143

A Single-donor platelets require more preparation time compared with random-donor
platelets because they are prepared by apheresis, which may require 1 to 3 hours,
depending on the instrumentation used. Pooling random donor platelets in equivalent
amounts may require only a few minutes

Question 144

28. What is the expiration of cryoprecipitate once pooled without the use of a sterile
    connecting device?
    A. 4 hours
    B. 6 hours
    C. 8 hours
    D. 24 hours
    Blood bank/Apply knowledge of standard operating procedures/Blood
    components/Expiration date/1

Answer 144

A When individual cryoprecipitate units are pooled in an open system, the expiration
time is 4 hours; if cryoprecipitate is pooled using a sterile connecting device, the
expiration time is 6 hours

Question 145

29. What is the number of WBCs permitted in a unit of leukocyte-reduced RBCs?
    A. Less than 5 × 1010
    B. Less than 5 × 106
    C. Less than 8.3 × 105
    D. Less than 8.3 × 106
    Blood bank/Apply knowledge of standard operating procedures/Blood components/1

Answer 145

B RBCs that have been leukocyte reduced must have fewer than 5 × 106 WBCs per unit.

Question 146

30. SITUATION: A patient with cancer recently developed a severe infection. The patient’s
    hemoglobin level is 8 g/dL as a result of chemotherapy with a drug known to cause bone
    marrow depression and immunodeficiency. Which blood products are indicated for this
    patient?
    A. Liquid plasma and cryoprecipitate
    B. Crossmatched platelets and washed RBCs
    C. Factor IX concentrates and FFP
    D. Irradiated RBCs, platelets, and granulocytes
    Blood bank/Correlate clinical and laboratory data/Blood and components/3

Answer 146

D The patient with cancer may be immunocompromised because of the medication used
but needs to receive RBCs for anemia; therefore, irradiated RBCs are indicated.
Platelets may be needed to control bleeding, and granulocytes may be indicated for
short-term control of severe infection.

Question 147

1. Which of the following individuals is acceptable as a blood donor?
   A. A 29-year-old man who received the hepatitis B vaccine last week
   B. A 21-year-old woman who had her nose pierced last week
   C. A 30-year-old man who lived in Zambia for 3 years and returned last month
   D. A 54-year-old man who tested positive for hepatitis C last year but has no active
   symptoms of disease
   Blood bank/Apply knowledge of standard operating procedures/Donor requirements/2

Answer 147

A If the donor is symptom free, there is no deferral period for the hepatitis B vaccine. Persons who have had body piercing are given a 12-month deferral. Persons who lived
in an area endemic for malaria or who received antimalarial drugs are deferred for 3
years. A positive test for the hepatitis C virus (HCV) is cause for indefinite deferral.

Question 148

2. SITUATION: A 53-year-old woman donates blood at her place of employment. She
   weighs 150 lb and has a hemoglobin level of 13 g/dL. She is currently on warfarin and
   vitamin B12. Is she an acceptable donor?
   A. Yes
   B. No, she is on warfarin
   C. Yes, for RBCs only
   D. No, her hemoglobin is too low
   Blood bank/Apply knowledge of standard operating procedures/Donor requirements/2

Answer 148

C Her age and hemoglobin meet donor criteria. However, because she is currently on
warfarin, only RBCs can be prepared from her donation.

Question 149

3. Which immunization has the longest deferral period?
   A. Hepatitis B immune globulin (HBIG)
   B. Rubella vaccine
   C. Influenza vaccine
   D. Yellow fever vaccine
   Blood bank/Apply knowledge of standard operating procedures/Donor requirements/1

Answer 149

A Deferral for HBIG injection is 12 months. Deferral for rubella vaccine is 4 weeks. The
deferral period for influenza and yellow fever vaccines is 2 weeks.

Question 150

4. The following whole blood donors regularly give blood. Which donor may donate on
   September 10?
   A. A 40-year-old woman who last donated on July 23
   B. A 28-year-old man who had plateletpheresis on August 24
   C. A 52-year-old man who made an autologous donation on September 9
   D. A 23-year-old woman who donated blood for her aunt on August 14
   Blood bank/Apply knowledge of standard operating procedures/Donor requirements/2

Answer 150

B A plateletpheresis donor must wait at least 48 hours between donations. The waiting
period following an autologous donation is at least 3 days. An 8-week interval must
pass between all other types of donations.

Question 151

5. Which of the following precludes acceptance of a plateletpheresis donor?
   A. Platelet count of 75 × 109/L in a donor who is a frequent platelet donor
   B. Plasma loss of 800 mL from plasmapheresis 1 week ago
   C. Plateletpheresis performed 4 days ago
   D. Aspirin ingested 7 days ago
   Blood bank/Apply knowledge of standard operating procedures/Donor requirements/1

Answer 151

A To be eligible for plateletpheresis, the platelet count should be greater than 150 × 109/L
for a frequent platelet donor. Plasma loss exceeding 1,000 mL would be cause for
rejection, but not 800 mL. A donor may donate 24 times a year, but not as frequent as
once every 2 days in a 7-day period. A donor cannot ingest aspirin within 36 hours of
platelet donation.

Question 152

6. Which of the following donors could be accepted for whole blood donation?
   A. A construction worker who was incarcerated for opiate abuse
   B. A triathlete with a pulse of 45
   C. A man who is currently taking finasteride (Propecia)
   D. A woman in her 14th week of pregnancy
   Blood bank/Apply knowledge of standard operating procedures/Donor requirements/2

Answer 152

B Athletes may have a pulse below 50 and may still be acceptable as blood donors. Drug
addiction is cause for permanent deferral, as is a major illness. The deferral period after
treatment for syphilis or gonorrhea is 12 months.

Question 153

7. Which physical examination result is cause for rejecting a whole blood donor?
   A. Weight of 105 lb
   B. Pulse of 75
   C. Temperature of 37.4°C (99.3°F)
   D. Diastolic pressure of 110 mm Hg
   Blood bank/Apply knowledge of standard operating procedures/Donor requirements/1

Answer 153

D Diastolic pressure must not be higher than 100 mm Hg. Donors weighing less than 110
lb may donate up to 12% of their blood volume (volume = weight in kg/50 × 450 mL).
Oral temperature must not be greater than 37.4°C (99.5°F). BP limits for donation are
180 mm Hg for systolic and 100 mm Hg for diastolic pressure. The limit for
hemoglobin is 12.5 g/dL and for hematocrit 38%.

Question 154

8. Which situation is not a cause for indefinite deferral of a donor?
   A. Male donor whose father has been diagnosed with Creutzfeldt-Jakob disease (CJD)
   B. Donation of a unit of blood that transmitted hepatitis B virus (HBV) to a recipient
   C. Donor tested reactive for HBV by nucleic acid testing (NAT)
   D. Accidental needlestick 1 year ago; negative for infectious disease
   Blood bank/Apply knowledge of standard operating procedures/Donor requirements/1

Answer 154

D An accidental needlestick would not be a cause for indefinite deferral of a donor. The
deferral period is 1 year.

Question 155

9. A whole blood donor currently on clopidogrel (Plavix) is precluded from donating which
   product?
   A. Platelets
   B. RBCs
   C. FFP
   D. Cryoprecipitate
   Blood bank/Select course of action/Donor processing/Unacceptable donors/1

Answer 155

A Clopidogrel (Plavix) renders platelets nonfunctional, and therefore potential donors on
this medication cannot donate platelets

Question 156

10. How much anticoagulant would have to be removed from the collection bag given a
    donor who weighs 90 lb?
    A. 12 mL
    B. 15 mL
    C. 20 mL
    D. 23 mL

Answer 156

A To determine the amount of anticoagulant to remove when the donor is less than 110
lb, divide weight by 110 lb, and multiply by 450 mL; divide that number by 100, and
multiply by 14 (this gives the anticoagulant volume needed); then subtract this from 63
mL, which is the standard volume of anticoagulant in a 450 mL bag. The result is the
amount of anticoagulant to remove.

Question 157

11. A woman begins to breathe rapidly while donating blood. Choose the correct course of
    action.
    A. Continue the donation; rapid breathing is not a reason to discontinue a donation
    B. Withdraw the needle, raise her feet, and administer ammonia
    C. Discontinue the donation, and provide a paper bag for donor to breathe slowly into
    D. Tell her to sit upright, and apply a cold compress to her forehead
    Blood bank/Select course of action/Donor processing/Donor adverse reactions/3

Answer 157

C This woman is hyperventilating; therefore, the donation should be discontinued. A
paper bag should be provided to the donor to breathe into to increase the carbon
dioxide in the donor’s air.

Question 158

12. A donor bag is half filled during donation when the blood flow stops. Select the correct
    course of action.
    A. Closely observe the bag for at least 3 minutes; if blood flow does not resume, withdraw
    the needle
    B. Remove the needle immediately, and discontinue the donation
    C. Check and reposition the needle, if necessary; if blood flow does not resume, withdraw
    the needle
    D. Withdraw the needle, and perform a second venipuncture in the other arm
    Blood bank/Select course of action/Collection/3

Answer 158

C If blood flow has stopped, check the needle first. If blood flow does not resume after
repositioning, then withdraw the needle and discontinue the donation. Do not perform
a second venipuncture on the donor.

Question 159

13. Who is the best candidate for a predeposit autologous donation?
    A. A 45-year-old man who is having elective surgery in 2 weeks; he has alloanti-k
    B. A 23-year-old female patient with leukemia and a hemoglobin level of 10 g/dL
    C. A 12-year-old boy who has hemophilia
    D. A 53-year-old woman who has septicemia
    Blood bank/Select course of action/Donor processing/Autologous donation/2

Answer 159

A The 45-year-old man with alloanti-k is the best candidate for predeposit autologous
donation because compatible blood will be hard to find if he needs blood after surgery.
The other candidates may not be good choices for donation because the process may
prove harmful to them.

Question 160

14. Can an autologous donor donate blood on Monday if he or she is having surgery on
    Friday?
    A. Yes, he or she can donate up to 72 hours before surgery
    B. No, he or she cannot donate within 7 days of surgery
    C. Yes, he or she can donate, but only a half a unit
    D. No, he or she cannot donate within 5 days of surgery
    Blood bank/Apply knowledge of standard operating procedures/Autologous donation/2

Answer 160

A An autologous donor can donate up to 72 hours before expected surgery.

Question 161

15. Which of the following is an acceptable time in which a unit of whole blood is collected?
    A. 33 minutes
    B. 25 minutes
    C. 20 minutes
    D. 13 minutes
    Blood bank/Apply knowledge of standard operating procedures/Collection/1

Answer 161

D A unit of whole blood should be collected within 15 minutes.

Question 162

16. Which of the following is true regarding acute normovolemic hemodilution?
    A. One or more units of blood are withdrawn from the patient and replaced with FFP
    B. Units removed may be stored in the operating room at room temperature for 8 hours
    C. Units removed may be stored in the operating room at room temperature for 24 hours
    D. Unused units can be added to the general donor blood inventory
    Blood bank/Apply knowledge of standard operating procedures/Autologous donation/2

Answer 162

B In acute normovolemic hemodilution, one or more units of blood are removed from the donor and replaced with crystalloid or colloid. Blood may be stored at room
temperature for up to 8 hours or at 1°C to 6°C for up to 24 hours. Bleeding during
surgery results in less RBC loss after hemodilution, and the autologous RBCs are
infused after bleeding stops. Such units are for autologous transfusion only.

Question 163

17. All of the following apply to a double RBC unit apheresis collection except:
    A. The hematocrit must be at least 38%
    B. The weight for a female is at least 150 lb
    C. The height for a male is at least 5 ft 1 in
    D. The deferral period following collection is 16 weeks
    Blood bank/Apply knowledge of standard operating procedures/Apheresis/1

Answer 163

A The minimum hematocrit for a double RBC donation is 40%.

Question 164

18. An autologous unit of whole blood was collected on a 33-year-old woman in preparation
    for a knee replacement procedure in 3 weeks. The whole blood unit had her hyphenated
    last name, first name, and last four digits of her social security number for
    identification. The laboratory computer system, however, only had her married name
    and first name, medical record number, and social security number. What should be
    done with this blood product?
    A. Discard the unit
    B. Make the unit available for transfusion
    C. Confirm the name with the donor, have admissions make the correction in the computer
    system, and then make the unit available for transfusion
    D. Ensure that social security numbers match, confirm the name with the donor and have
    admissions make the correction in the computer system with the medical director’s
    approval, and then make the unit available for transfusion
    Blood bank/Standard operating procedures/Autologous donation/3

Answer 164

D This is a common scenario with women who have recently married, and have not
changed their license or other form of identification given to the collection facility.
Checking that other demographic information matches is sufficient, if approved by the
medical director, because an autologous unit is very difficult to replace in time for
surgery.

Question 165

19. What is the youngest age a person can make allogeneic whole blood donation?
    A. 14 years
    B. 15 years
    C. 16 years
    D. 17 years
    Blood bank/Apply knowledge of standard operating procedures/Donation/1

Answer 165

C In most states, the youngest age a person can donate is 16 years with parental
permission

Question 166

20. Which of the following donors are acceptable for whole blood donation?
    A. A man who had sex with another man 2 weeks ago
    B. A male construction worker who tested positive for hepatitis B surface antigen (HBsAg)
    C. A man who had sex with another man 2 years ago
    D. A female who had sex with a male who had sex with another male (MSM) 1 month ago
    Blood bank/Apply knowledge of standard operating procedures/Donors/1

Answer 166

C Men who have sex with men can donate blood if they have not had sex with another
man in the past year.

Question 167

1. All of the following are reasons for a positive DAT on cord blood cells of a newborn
   except:
   A. High concentrations of Wharton jelly on cord blood cells
   B. Immune anti-A from an O mother on the cells of an A baby
   C. Immune anti-D from an Rh negative mother on the cells of an Rh-positive baby
   D. Immune anti-K from a K-negative mother on the cells of a K-negative baby
   Blood bank/Correlate clinical and laboratory data/Hemolytic disease of the fetus and
   newborn/DAT/2

Answer 167

D Immune anti-K from the mother would not coat the baby’s RBCs if they did not
contain the K antigen; therefore, the DAT result would be negative.

Question 168

2. A fetal screen yielded negative results on a mother who is O negative and infant who is
   O positive. What course of action should be taken?
   A. Perform a Kleihauer-Betke test
   B. Issue one full dose of RhIg
   C. Perform a DAT on the infant
   D. Perform an antibody screen on the mother
   Blood bank/Select course of action/Hemolytic disease of the fetus and newborn/Rosette test/3

Answer 168

B If the fetal screen or rosette test has a negative result, indicating the fetal maternal
blood is negligible in a possible RhIg candidate, standard practice is to issue one dose
of RhIg

Question 169

3. What should be done when a woman who is 24 weeks pregnant has a positive antibody
   screen?
   A. Perform an antibody identification panel; titer, if necessary
   B. No need to do anything until 30 weeks’ gestation
   C. Administer RhIg
   D. Adsorb the antibody onto antigen-positive cells
   Blood bank/Apply knowledge of standard operating procedures/Hemolytic disease of the
   fetus and newborn/Antibody testing/2

Answer 169

A The identification of the antibody is very important at this stage of the pregnancy. If
the antibody is determined to be clinically significant, then a titer may determine the
strength of the antibody and the need for clinical intervention

Question 170

4. All of the following are interventions for fetal distress caused by maternal antibodies
   attacking fetal cells except:
   A. Intrauterine transfusion
   B. Plasmapheresis on the mother
   C. Transfusion of antigen-positive cells to the mother
   D. Middle cerebral artery peak systolic velocity (MCA-PSV)
   Blood bank/Apply knowledge of standard operating procedures/Hemolytic disease of the
   fetus and newborn/Clinical interventions/2

Answer 170

C Transfusion of antigen-positive cells to the mother who already has an antibody might
cause a transfusion reaction and/or evoke an even stronger antibody response, possibly
causing more harm to the fetus.

Question 171

5. Cord blood cells are washed six times with saline, and the DAT result and negative
   control are still positive. What should be done next?
   A. Obtain a heelstick sample
   B. Record the DAT result as positive
   C. Obtain another cord blood sample
   D. Perform elution on the cord blood cells
   Blood bank/Select course of action/Hemolytic disease of the fetus and newborn/DAT/3

Answer 171

A If the cord blood cells contain excessive Wharton jelly, then further washing or
obtaining another cord blood sample will not solve the problem. A heelstick sample
will not contain Wharton jelly and should give a valid DAT result.

Question 172

6. What can be done if HDFN is caused by maternal anti-K?
   A. Give Kell immune globulin
   B. Monitor the mother’s antibody level
   C. Prevent formation of K-positive cells in the fetus
   D. Not a problem; anti-K is not known to cause HDFN
   Blood bank/Apply principles of special procedures/Hemolytic disease of the fetus and
   newborn/Antibody formation/2

Answer 172

B Anti-D is the only antibody for which prevention of HDFN is possible. If a pregnant
woman develops anti-K, she will be monitored to determine if the antibody level and
signs of fetal distress necessitate clinical intervention.

Question 173

7. Should an O-negative mother receive RhIg if a positive DAT on the newborn is caused
   by immune anti-A?
   A. No, the mother is not a candidate for RhIg because of the positive DAT result
   B. Yes, if the baby’s type is Rh negative
   C. Yes, if the baby’s type is Rh positive
   D. No, the baby’s problem is unrelated to Rh blood group antibodies
   Blood bank/Correlate clinical and laboratory data/Hemolytic disease of the fetus and
   newborn/RhIg/3

Answer 173

C RhIg is immune anti-D and is given to Rh-negative mothers who give birth to Rhpositive
babies and who do not have anti-D already formed from previous pregnancies
or transfusion

Question 174

8. Should an A-negative woman who has just had a miscarriage receive RhIg?
   A. Yes, but only if she does not have evidence of active anti-D
   B. No, the type of the baby is unknown
   C. Yes, but only a minidose regardless of trimester
   D. No, RhIg is given to women at full-term pregnancies only
   Blood bank/Apply knowledge of standard operating procedures/Hemotherapy/RhIg/3

Answer 174

A When the fetus is Rh positive or the Rh status of the fetus is unknown, termination of a
pregnancy from any cause presents a situation in which an Rh-negative patient should
receive RhIg. A minidose is used if the pregnancy is terminated in the first trimester.

Question 175

9. SITUATION:. The automated blood bank analyzer reports a type of O negative on a
   woman who is 6 weeks pregnant with vaginal bleeding. The woman tells the emergency
   department physician she is O positive and presents a blood donor card. The MLS
   performs a test for weak D and observes a 1+ reaction in the AHG phase. The
   Kleihauer-Betke test result is negative. Is this woman a candidate for RhIg?
   A. Molecular testing is indicated to ascertain the type of weak D
   B. Yes, she is Rh positive
   C. No, there is no evidence of a fetal bleed
   D. Yes, based on the automated typing results
   Blood bank/Correlate clinical and laboratory results/Hemolytic disease of the fetus and
   newborn/RhIg/3

Answer 175

A The negative Kleihauer-Betke test result confirms that the positive reaction of the
woman’s RBCs with anti-D at the IAT phase is not the result of fetal–maternal
bleeding. The woman is weak D positive and, therefore, requires molecular testing to
discern if she is a candidate for RhIg. Weak D types 1, 2, 3, and 4 do not make anti-D
and do not require RhIg prophylaxis.

Question 176

10. Which of the following patients would be a candidate for RhIg?
    A. B-positive mother; B-negative baby; first pregnancy; no anti-D in mother
    B. O-negative mother; A-positive baby; second pregnancy; no anti-D in mother
    C. A-negative mother; O-negative baby; fourth pregnancy; anti-D in mother
    D. AB-negative mother; B-positive baby; second pregnancy; anti-D in mother
    Blood bank/Correlate clinical and laboratory data/Hemolytic disease of the fetus and
    newborn/RhIg/2

Answer 176

B An O-negative mother who gives birth to an A-positive baby and has no anti-D
formed from a previous pregnancy would be a candidate for RhIg. A mother who
already has active anti-D or a mother who gives birth to an Rh-negative baby is not a
candidate for RhIg. Anti-D formation via active immunization typically has a titer
greater than 4, compared with passive administration of anti-D, which has a titer less
than 4.

Question 177

11. The Kleihauer-Betke acid elution test identifies 40 fetal cells in 2,000 maternal RBCs.
    How many full doses of RhIg are indicated?
    A. 1
    B. 2
    C. 3
    D. 4
    Blood bank/Calculate/Hemolytic disease of the fetus and newborn/RhIg/2

Answer 177

D To calculate the number of vials of RhIg to infuse, divide 40 by 2,000, and multiply by 5,000. This gives the estimated total blood volume of the mother in milliliters.
Divide this number by 30 to obtain the number of doses. When the number to the right
of the decimal point is less than 5, round down, and add one dose of RhIg. Conversely,
when the number to the right of the decimal point is 5 or greater, round up, and add
one dose of RhIg. In this example, the number of doses is 3.3. Rounding down and
adding one vial gives an answer of four vials

Question 178

12. Kernicterus is caused by the effects of:
    A. Anemia
    B. Unconjugated bilirubin
    C. Antibody specificity
    D. Antibody titer
    Blood bank/Apply knowledge of biological principles/Hemolytic disease of the fetus and
    newborn/1

Answer 178

B Kernicterus occurs because of high levels of unconjugated bilirubin. High levels of
this pigment cross into the central nervous system, causing brain damage to the infant.

Question 179

13. Anti-E is detected in the serum of a woman in the first trimester of pregnancy. The first
    titer for anti-E is 32. Two weeks later, the antibody titer is 64 and then 128 after
    another 2 weeks. Clinically, there are beginning signs of fetal distress. What may be
    done?
    A. Induce labor for early delivery
    B. Perform plasmapheresis to remove anti-E from the mother
    C. Administer RhIg to the mother
    D. Perform an intrauterine transfusion using E-negative cells
    Blood bank/Correlate clinical and laboratory data/Hemolytic disease of the fetus and
    newborn/3

Answer 179

B Plasmapheresis removes excess anti-E from the mother and provides a temporary
solution to the problem until the fetus is mature enough to be delivered. The procedure
may need to be performed several times, depending on how quickly and how high the
levels of anti-E rise. Administration of RhIg would not contribute to solving this
problem caused by anti-E. Intrauterine transfusion would not be performed before
week 20 and would be considered only if there is evidence of severe hemolytic disease.

Question 180

14. What testing is done for exchange transfusion when the mother’s serum contains an
    alloantibody?
    A. Crossmatching and antibody screen
    B. ABO, Rh, antibody screen, and crossmatching
    C. ABO, Rh, antibody screen
    D. ABO and Rh only
    Blood bank/Apply knowledge of standard operating procedures/Hemolytic disease of the
    fetus and newborn/Hemotherapy/1

Answer 180

B ABO (forward) and Rh are required. An antibody screen using either the neonatal
serum or maternal serum is required. Crossmatching is necessary as long as maternal
antibody persists in the infant’s blood.

Question 181

15. Which blood type may be transfused to an AB-positive baby who has HDFN caused by
    anti-D?
    A. AB negative, CMV negative, Hgb S negative; irradiated or O negative, CMV negative,
    Hgb S negative
    B. AB positive, CMV negative; irradiated or O positive, CMV negative
    C. AB negative only
    D. O negative only
    Blood bank/Select course of action/Hemolytic disease of the fetus and
    newborn/Hemotherapy/2

Answer 181

A Either AB-negative or O-negative RBCs may be given to an AB-positive baby
because both types are ABO compatible and lack the D antigen.

Question 182

16. All of the following are routinely performed on a cord blood sample except:
    A. Forward ABO typing
    B. Antibody screen
    C. Rh typing
    D. DAT
    Blood bank/Apply knowledge of laboratory operations/Hemolytic disease of the fetus and
    newborn/Cord blood/1

Answer 182

B An antibody screen is not performed routinely on a cord blood sample because a baby
does not make antibodies until about 6 months of age. Any antibodies detected in a
cord blood sample come from the mother.

Question 183

17. Why do Rh-negative women tend to have a positive antibody screen compared with Rhpositive
    women of childbearing age?
    A. They have formed active anti-D
    B. They have received RhIg
    C. They have formed anti-K
    D. They have a higher rate of transfusion
    Blood bank/Apply knowledge of biological principles/Hemolytic disease of the fetus and
    newborn/2

Answer 183

B The most common reason an Rh-negative woman has a positive antibody screen is
because of previously receiving RhIg or passive anti-D.

Question 184

18. SITUATION: An O-negative mother gave birth to a B-positive infant. The mother had
    no history of antibodies or transfusion. This was her first child. The baby was mildly
    jaundiced, and the DAT result was weakly positive with polyspecific antisera. What
    could have caused the positive DAT result?
    A. Anti-D from the mother coating the infant RBCs
    B. An alloantibody, such as anti-K, coating the infant RBCs
    C. Maternal anti-B coating the infant RBCs
    D. Maternal anti-A, B coating the infant RBCs
    Blood bank/Correlate clinical and laboratory data/Hemolytic disease of the fetus and
    newborn/3

Answer 184

D Anti-A,B is an IgG antibody and can cross the placenta and attach to infant cells. It is
known as a single entity as opposed to separate antibodies. Anti-D would not be the
cause because this is the first pregnancy. Anti-K is not the cause because there is no
history of alloantibodies or past transfusions.

Question 185

19. SITUATION: RhIg is requested on a 28-year-old woman with suspected abortion.
    When the nurse arrives in the blood bank to pick up the RhIg, she asks the MLS if it is
    a minidose. The MLS replies that it is a full dose, not a minidose. The nurse then requests to take 50 μg from the 300 μg syringe to satisfy the physician’s orders. What
    course of action should the MLS take?
    A. Let the nurse take the syringe of RhIg, so that she may withdraw 50 μg
    B. Call a supervisor or pathologist
    C. Instruct the nurse that the blood bank does not stock minidoses of RhIg and manipulating
    the full dose will compromise the purity of the product
    D. Instruct the nurse that the blood bank does not stock minidoses of RhIg, and relay this
    information to the patient’s physician
    Blood bank/Select course of action/Hemolytic disease of the fetus and newborn/RhIg/3

Answer 185

D Blood banks operate by strict standard operating procedures. These include decisions
about which products are supplied from the blood bank. Although B may also be a
solution, D is the best answer because the patient’s physician can communicate with
the pathologist once he or she receives this information from the nurse.

Question 186

1. What protocol is followed when screening whole blood donors for HIV-1 RNA?
   A. Pools of 10 are tested; if the pool is nonreactive, donors are accepted
   B. Pools of 20 are tested; if the pool is reactive, samples are tested individually
   C. Pools of up to 16 donors are tested; if pool is reactive, individual samples are screened
   D. All donors are screened individually; if samples are reactive, blood is discarded
   Blood bank/Standard operating procedures/Processing/3

Answer 186

C Pools of up to 16 donors are tested by nucleic acid amplification technology. If the
pool is reactive, samples from each individual donor are tested. Pooled donors may also be screened for Zika virus using nucleic acid amplification

Question 187

2. Currently, nucleic acid testing (NAT) testing is performed to detect which viruses?
   A. HIV and Human T-cell lymphotropic virus (HTLV-1)
   B. HTLV I/II
   C. HIV, HCV, HBV, Zika, and West Nile virus (WNV)
   D. HIV, HBV, and WNV
   Blood bank/Apply knowledge of standard operating procedures/Processing/1

Answer 187

C According to the AABB standards, NAT testing is required for viruses HIV-1, HCV,
HBV, Zika, and WNV.

Question 188

3. John comes in to donate a unit of whole blood at the collection center of the community
   blood supplier. The enzyme immunoassay assay (EIA) screen for anti-HIV-1,2 is
   nonreactive; however, the NAT HIV is reactive. After 8 weeks John is tested again and
   found to be NAT nonreactive and EIA anti-HIV-1,2 nonreactive:
   A. This renders him eligible for donation
   B. Donation is deferred for 6 months
   C. Status is dependent on further confirmatory testing
   D. Donation is deferred for 12 months
   Blood bank/Select course of action/Processing/3

Answer 188

A According to the FDA guidelines, donors who retest as NAT HIV nonreactive and
negative for anti-HIV-1,2 are eligible to donate in their re-entry program.

Question 189

4. What marker is the first to appear in HBV infection?
   A. Hepatitis B core antibody (anti-HBc) IgM
   B. HbsAg
   C. Hepatitis B surface antibody (anti-HBs)
   D. Anti-HBc IgG
   Blood bank/Apply knowledge of biological principles/Processing/1

Answer 189

B The first viral marker of hepatitis B to appear in the serum once exposed is the HBSAg,
which appears in as few as 5 days (5–28 days) after exposure.

Question 190

5. What marker indicates immunity to hepatitis B infection?
   A. Anti-HBc IgM
   B. HBsAg
   C. Anti-HBs
   D. Anti-HBc IgG
   Blood bank/Apply knowledge of standard operating procedures/Processing/1

Answer 190

C Anti-HBs is indicative of immunity or vaccination to hepatitis B. Anti-HBc IgM occurs
in the early stage of infection; anti-HBc IgG follows and may persist for years
following infection. HBsAg is a marker of HBV infection, not immunity.

Question 191

6. A patient with multiple myeloma is placed on daratumumab (Darzalex). What tests are
   affected by this drug, and what are typical recommendations for transfusion?
   A. Antibody screen/least incompatible RBCs
   B. ABO/washed RBCs
   C. Rh/leukocyte-poor RBCs
   D. All of the above
   Blood bank/Select best course of action/Processing/3

Answer 191

Daratumumab (Darzalex) is a monoclonal antibody directed against CD38, which
shows enhanced expression on multiple myeloma tumor cells. Because CD38 is also
expressed on RBCs, all screening cells will be positive. The serological workup
appears as a warm autoantibody that cannot be resolved with adsorptions and often
necessitates the transfusion of least incompatible RBCs.

Question 192

7. A unit tests positive for syphilis with use of the rapid plasma reagin (RPR) test. The
   Treponema pallidum particle agglutination (TP-PA) test on the same unit is negative.
   What is the disposition of the unit?
   A. The unit may be used to prepare components
   B. The donor must be contacted and questioned further; if the RPR test result is most likely a
   false positive, then the unit may be used
   C. The unit must be discarded
   D. Cellular components may be prepared but must be irradiated before issue
   Blood bank/Apply knowledge of standard operating procedures/Processing/2

Answer 192

A This is a case of a false-positive screening test result (RPR). The confirmatory test for
treponemal antibodies was negative. The donor unit is acceptable and may be used to
prepare blood components.

Question 193

8. SITUATION: John Smith donated a unit of whole blood in May. RBCs made from
   whole blood were transfused to a recipient at a community hospital in June, with no
   apparent complications. The blood supplier notified the medical director of the hospital
   that the donor had reported engaging in high-risk behavior with another male in April,
   although viral tests remain negative and the donor is healthy. What course of action
   should be taken?
   A. No action should be taken
   B. The recipient’s physician should be notified
   C. The recipient’s physician and the recipient should be notified
   D. The recipient should be notified
   Blood bank/Apply knowledge of biological principles/Market withdrawal/3

Answer 193

B The recipient’s physician should be notified by the medical director to ascertain the
current health status of the recipient, if known, and determine what treatment, if any,
the recipient should receive

Question 194

9. All of the following are required tests on donor blood, except:
   A. HBsAg
   B. Anti-CMV
   C. HIV-1
   D. Anti-HTLV I/II
   Blood bank/Apply knowledge of standard operating procedures/Processing/1

Answer 194

B Testing of donor blood for antibodies to CMV is not required. However, testing may be
done on units intended for transfusion to low-birth-weight infants born to seronegative
mothers or units used for intrauterine transfusion; units intended for
immunocompromised patients who are seronegative; prospective transplant recipients
who are seronegative; or transplant recipients who have received a seronegative organ.
Leukocyte-reduced RBCs carry a reduced risk of transmitting CMV and are
recommended for such patients when CMV testing has not been performed on donor
units. The prevalence of anti-CMV in the population ranges from 40% to 90%.

Question 195

10. Which of the following bands would constitute a positive Western Blot result for HIV?
    A. p24, gp41, p17
    B. p55, gp120, p51
    C. gp160, p31, p56
    D. p24, p30, p55
    Blood bank/Apply knowledge of standard operating procedures/Processing/1

Answer 195

A According to current FDA and CDC criteria, a sample is defined as anti-HIV positive
if at least two of the following bands are present on Western blot: p24, gp41, and/or
GP120/160.

Question 196

1. Is there a discrepancy between the following blood typing and secretor study results?
   Blood typing results: Anti-A Anti-B A1 Cells B Cells
   4+ 0 0 4+
   Secretor results: Anti-A + saliva + A1 cells = 0
   Anti-B + saliva + B cells = 4+
   Anti-H + saliva + O cells = 0
   A. No problem, the sample is from a group A secretor
   B. Blood types as A and saliva types as B
   C. Blood types as A, but the secretor study is inconclusive
   D. No problem, the sample is from a group A nonsecretor
   Blood bank/Evaluate laboratory data to make identifications/Saliva neutralization/3

Answer 196

A The blood typing result demonstrates A antigen on the RBCs and anti-B in serum. The
secretor result reveals A antigen in the saliva. A antigen neutralized anti-A, preventing
agglutination when A1 cells were added. Each blood type (except a Bombay
phenotype) contains some H antigen; therefore, H antigen in saliva would be bound by
anti-H reagent. No agglutination would occur when O cells are added.

Question 197

2. What is the best course of action given the following test result? (Assume the patient has
   not been transfused recently.)
   Anti-A Anti-B A1 cells B cells
   Mixed field 0 1+ 4+
   A. Nothing, typing is normal
   B. Type patient cells with anti-A1 lectin and type serum with A2 cells
   C. Retype patient cells; type with anti-H and anti-A,B; use screen cells or A2 cells on patient
   serum; run patient autocontrol
   D. Wash patient cells four times with saline; then repeat the forward type
   Blood bank/Apply principles of special procedures/RBCs/ABO discrepancy/3

Answer 197

C The mixed-field reaction with anti-A suggests a subgroup of A, most likely A3. The
reverse grouping shows weak agglutination with A1 cells, indicating anti-A1. A
positive reaction with anti-A,B would help to differentiate an A subgroup from group
O. If A2 cells are not agglutinated by patient serum, the result would indicate the
presence of anti-A1. If the patient’s serum agglutinates A2 cells, then an alloantibody
or autoantibody should be considered.

Question 198

3. The following results were obtained on a 41-year-old female:
   Anti-A Anti-B A1 cells B cells O cells
   4+ 0 3+ 4+ 3+
   Due to the discrepant reverse grouping, a panel was performed on patient serum
   revealing the presence of anti-M. How can the reverse grouping be resolved?
   A. Repeat the reverse grouping with a 10-minute incubation at room temperature
   B. Repeat the reverse grouping using A1 cells that are negative for M antigen
   C. Repeat the reverse grouping using A1 cells that are positive for M antigen
   D. No further work is necessary
   Blood bank/Evaluate laboratory data to recognize problems/ABO discrepancy/3

Answer 198

B The scenario showed an antibody in the patient serum directed toward M antigen, and
the M antigen happened to be on the A1 cells in reverse grouping. To solve this
problem, find A1 cells negative for M antigen or enzyme treat the A1 cells to resolve
the ABO discrepancy.

Question 199

5. The following results were obtained on a 51-year-old male with hepatitis C:
   Anti-A Anti-B Anti-D A1 cells B cells
   4+ 4+ 3+ 0 0
   What should be done next?
   A. Retype the patient’s sample to confirm group AB positive
   B. Repeat the Rh typing
   C. Run a saline control in forward grouping
   D. Report the patient as group AB, Rh positive
   Blood bank/Apply knowledge of routine laboratory procedures/ABO/2

Answer 199

C In the case of an AB-positive person, a saline control must be run in forward grouping
to obtain a negative reaction; this will ensure agglutination is specific in the other
reactions.

Question 200

6. An Rh phenotyping shows the following results:
   Anti-D Anti-C Anti-E Anti-c Anti-e
   4+ 2+ 0 0 3+
   What is the most likely Rh genotype?
   A. R1r’
   B. R0r
   C. R1R1
   D. R1r
   Blood bank/Apply knowledge of fundamental biological characteristics/Rh typing/3

Answer 200

.C The most likely genotype is R1R1.The possibilities are DCe/DCe or DCe/dCe, which
translates to R1R1 or R1h’. The former is more common.

Question 201

7. An obstetric patient, 34 weeks pregnant, shows a positive antibody screen at the indirect
   antiglobulin phase of testing in screening cells I and II; screening cell III was negative.
   She is group B, Rh negative. This is her first pregnancy. She has no prior history of
   transfusion. What is the most likely explanation for the positive antibody screen?
   A. She has developed an antibody to fetal RBCs
   B. She probably does not have antibodies because this is her first pregnancy, and she has not
   been transfused; check for technical error
   C. She received an antenatal dose of RhIg
   D. Impossible to determine without further testing
   Blood bank/Correlate clinical and laboratory data/Hemolytic disease of the fetus and
   newborn/3

Answer 201

C Because the patient has never been transfused or pregnant previously, she probably has
not formed any atypical antibodies. Because she is Rh negative she would have
received a dose of RhIg at 28 weeks (antenatal dose) if her prenatal antibody screen
had been negative. Although technical error cannot be ruled out, it is far less likely
than RhIg administration to be the cause.

Question 202

8. A patient’s serum contains a mixture of antibodies. One of the antibodies is identified as
   anti-D. Anti-Jka or anti-Fya and possibly another antibody are present. What
   technique(s) may be helpful to identify the other antibody(s)?
   A. Enzyme panel; select cell panel
   B. Thiol reagents
   C. Lowering the pH and increasing the incubation time
   D. Using albumin as an enhancement medium in combination with selective adsorption
   Blood bank/Apply principles of special procedures/Antibody ID/3

Answer 202

A An enzyme panel would help to distinguish between anti-Jka (reaction enhanced) and
anti-Fya (destroyed). Anti-D, however, would also be enhanced and may mask
reactions that may distinguish another antibody. A select panel of cells negative for D
may help to reveal an additional antibody or antibodies.

Question 203

9. An anti-M reacts strongly through all phases of testing. Which of the following
   techniques would not contribute to removing this reactivity so that more clinically
   significant antibodies may be revealed?
   A. Acidifying the serum
   B. Prewarmed technique
   C. Adsorption with homozygous cells
   D. Testing with enzyme-treated RBCs
   Blood bank/Apply principles of special procedures/Antibody ID/3

Answer 203

A Lowering the pH will actually enhance reactivity of anti-M. Prewarming (anti-M is a
cold-reacting antibody), cold adsorption with homozygous M cells, and testing the
serum with enzyme-treated RBCs (destroys M antigens) are all techniques to remove
reactivity of anti-M.

Question 204

10. The reactivity of an unknown antibody could be anti-Jka, but the antibody
    identification panel does not fit this pattern conclusively. Which of the following would
    not be effective in determining if the specificity is anti-Jka?
    A. Testing with enzyme-treated cells
    B. Select panel of homozygous cells
    C. Testing with 2-aminoethylisothiouronium bromide (AET)–treated cells
    D. Increased incubation time
    Blood bank/Apply principles of special procedures/Antibody ID/3

Answer 204

C AET denatures Kell antigens and has no effect on Kidd antibodies. Because the
detection of Kidd antibodies is subject to dosage effect, selection of cells homozygous
for the Jka antigen (and longer incubation) would help to detect the presence of the
corresponding antibody. Enzyme-treated RBCs would also react more strongly in the
presence of Kidd antibodies.

Question 205

11. A cold-reacting antibody is found in the serum of a recently transfused patient and is
    suspected to be anti-I. The antibody identification panel shows reactions with all cells at
    room temperature, including the autocontrol. The reaction strength varies from 2+ to
    4+. What procedure would help to distinguish this antibody from other cold-reacting
    antibodies?
    A. Autoadsorption technique
    B. Neutralization using saliva
    C. Autocontrol using ZZAP reagent-treated cells
    D. Reaction with cord blood cells
    Blood bank/Apply principles of special procedures/Antibody ID/3

Answer 205

D Because RBCs contain variable amounts of I antigen, reactions with anti-I often vary
in agglutination strength. However, because this patient was recently transfused, the
variation in reaction strength may be the result of an antibody mixture. Although
autoadsorption would remove anti-I, this procedure does not confirm the antibody
specificity and can result in removal of other antibodies, as well. Cord blood cells
express primarily i antigen with very little I antigen. Anti-I would react weakly or
negatively with cord RBCs. ZZAP removes IgG antibodies from RBCs. Because anti-I
is IgM, the use of ZZAP would not be of value.

Question 206

12. An antibody identification panel reveals the presence of anti-Leb and a possible second
    specificity. Saliva from which person would best neutralize the Leb antibody?
    Genes
    Lewis ABO Secretor
    A. Le H sese
    B. Le hh Se
    C. Le H Se
    D. lele hh sese
    Blood bank/Apply principles of special procedures/Antibody ID/3

Answer 206

C Lewis antibodies are usually not clinically significant but may interfere with testing
for clinically significant antibodies. Lewis antibodies are most easily removed by
neutralizing them with soluble Lewis substance. Lewis antigens are secreted into saliva
and plasma and are adsorbed onto RBCs. Leb substance is made by adding an L-fucose
to both the terminal and next to last sugar residue on the type 1 precursor chain. This
requires the Le, H, and Se genes. Because some samples of anti-Leb react only with
group O or A2 RBCs, neutralization is best achieved if the saliva comes from a person
who is group O.

Question 207

13. The automated blood bank analyzer does not detect weak forms of D antigen. Why
    would running type and screens on the analyzer prevent a patient with a weak D
    phenotype from forming anti-D?
    A. Weak D persons cannot form anti-D
    B. The analyzer would show the sample as Rh negative; the patient would receive Rhnegative
    blood
    C. The analyzer would show the sample as Rh positive; the patient would receive Rhpositive
    blood
    D. A and C
    Blood bank/Correlate clinical and laboratory data/Blood group antigens/2

Answer 207

B The automated analyzer would result the patient with a weak D phenotype as Rh
negative, and if blood were needed, the patient would receive Rh-negative blood.

Question 208

14. A cord blood workup was ordered on baby boy Jones. The mother is O negative.
    Results on the baby are as follows:
    Anti-A Anti-B Anti-A, B Anti-D DAT (poly)
    4+ 0 4+ 0 2+
    The test for weak D on the baby was positive at the AHG phase. Is the mother an RhIg
    candidate?
    A. No, the baby is Rh positive
    B. Yes, the baby’s Rh type cannot be determined because of the positive DAT result
    C. No, the baby is Rh negative
    D. Yes, the mother is Rh negative
    Blood bank/Evaluate laboratory data/Rh type/3

Answer 208

B The baby forward types as an A, and the mother is O negative. It is possible that anti-
A,B from the mother is attaching to the baby’s RBCs, causing a positive DAT result.
In the presence of a positive DAT, a weak test for D is not valid. Therefore, the baby’s
Rh type is unknown, and the mother would be a candidate for RhIg.

Question 209

15. RBCs from a recently transfused patient were positive on DAT when tested with anti-
    IgG. Screen cells and a panel performed on a patient’s serum showed very weak
    reactions with inconclusive results. What procedure could help to identify the antibody?
    A. Elution followed by a panel on the eluate
    B. Adsorption followed by a panel on the adsorbed serum
    C. Enzyme panel
    D. Antigen typing the patient’s RBCs
    Blood bank/Apply principles of special procedures/Antibody identification/3

Answer 209

A If the RBCs show a positive DAT result, then IgG antibody has coated incompatible,
antigen-positive RBCs. If screening cells and panel cells show missing or weak
reactions, most of the antibody is on the RBCs and would need to be eluted before it
can be detected. An elution procedure followed by a panel performed on the eluate
would help to identify the antibody.

Question 210

16. A patient types as O positive. All three screening cells and RBCs from two O-positive
    donor units show agglutination after incubation at 37°C and increase in reactivity at the
    IAT phase of testing. What action should be taken next?
    A. Perform an autocontrol and DAT on the patient
    B. Perform an enzyme panel
    C. Perform an elution
    D. Choose another 2 units and repeat crossmatching
    Blood bank/Select course of action/Incompatible crossmatch/3

Answer 210

A All screening cells and all units are positive at both 37°C and the IAT phase. This
indicates the possibility of a high-frequency alloantibody or a warm autoantibody. An
autocontrol would help make this distinction. A positive autocontrol indicates an
autoantibody is present; a negative autocontrol and positive screen cells indicate an
alloantibody. A DAT would be performed to determine if an antibody has coated the
patient’s RBCs and is directed against screening cells and donor cells.

Question 211

17. Four units of blood are ordered for a patient. Blood bank records are checked and
    indicate that 5 years ago this patient had an anti-Jkb. What is the next course of action?
    A. Antigen type units for the Jkb antigen, and only crossmatch units positive for Jkb
    B. Antigen type units for the Jkb antigen, and only crossmatch units negative for Jkb
    C. Randomly pull 4 units of blood that are ABO compatible, and perform crossmatching
    D. Perform IS crossmatching on 4 Jkb-negative units
    Blood bank/Apply principles of laboratory operations/Compatibility testing/3

Answer 211

B A patient with a history of a significant antibody, such as anti-Jkb, must receive blood
that has been completely crossmatched and is negative for the corresponding antigen;
otherwise, an anamnestic reaction may occur with subsequent lysis of donor cells.

Question 212

18. A 56-year-old patient diagnosed with colon cancer demonstrates a positive antibody
    screen in all three screen cells at the AHG phase. The panel study shows 10 cells as
    positive as well as the autocontrol at the AHG phase. The reactions varied from 1+ to
    3+. This patient had a history of receiving 2 units of blood approximately 1 month ago.
    What should be done next?
    A. Perform a DAT on patient cells
    B. Perform an autoadsorption
    C. Perform an alloadsorption
    D. Issue O-negative cells
    Blood bank/Evaluate laboratory data to determine best course of action/Panel study/3

Answer 212

C In this situation, an allogeneic adsorption must be performed to adsorb out the
autoantibody and leave potential alloantibodies in the patient’s serum that will need to be identified before transfusion of blood to the patient. An autoadsorption cannot be
performed because any alloantibodies would be absorbed by circulating donor cells
present from the previous month.

Question 213

19. A 33-year-old maternity patient has blood drawn for a type and screen at 36 weeks’
    pregnancy. The following results are found on the automated blood bank analyzer:
    Anti-A Anti-B Anti-A,B Anti-D A1 cells B cells
    3+ 0 4+ 4+ 2+ 4+
    SC I SC II SC III A1 lectin
    0 0 0 3+
    The reference laboratory identified anti-P1 in the patient plasma by using enzyme
    techniques. How could the ABO discrepancy be solved?
    A. Wash the patient’s RBCs, and repeat the forward grouping
    B. Test the patient’s plasma against A2 cells
    C. Warm the patient’s plasma at 37°C for 10 minutes, and repeat the reverse grouping
    D. Treat the A1 cells with DTT, and repeat the reverse grouping
    Blood bank/Evaluate laboratory data to determine possible inconsistent results/ABO/3

Answer 213

C Anti-P1 is a cold-reacting antibody. Warming the plasma at 37°C will dissipate the
antibody, preventing its reactivity with P1 antigen on the A1 cells.

Question 214

20. An O-negative mother with no record of any previous pregnancies gives birth to her
    first child, a B-positive baby. The baby’s DAT is weakly positive, and the saline control
    is negative. The antibody screen is also negative. The baby appears healthy but after 2
    days develops mild jaundice, which is treated with phototherapy. After 4 days in the
    hospital, the baby goes home, without complications. What is the most likely
    explanation for the weakly positive DAT result?
    A. Technical error
    B. A low-titer anti-D
    C. Immune anti-B from the mother
    D. A maternal antibody against a low-incidence antigen
    Blood bank/Correlate clinical and laboratory data/Hemolytic disease of the fetus and
    newborn/2

Answer 214

20. C In this case, the maternal anti-A,B is probably coating the infant’s B cells, causing a
    positive DAT and jaundice. Anti-A,B from an O person is a single entity that cannot be
    separated. It is IgG and can cross the placenta. This antibody may attach to A, B, or
    AB RBCs.