Blood bank and Blood Transfusion Medicine (Book questions)

1. Which immunodominant sugar confers A antigen

specificity?

a. D-Galactose

b. L-Fucose

c. N-Acetylgalactosamine

d. Both A and C

c. N-Acetylgalactosamine

(GalNAc) confers type

A specificity. D-Galactose (Gal) confers type

B specificity. L-Fucose (Fuc) confers typeOspecificity.

The type A and type B sugars are built on Fuc.

If a patient has an A2 ABO type, which of the following

statements is true?

a. The patient's red cells will react with anti-A1 lectin

b. The patient's serum will react with A2 cells

c. The patient's red cells will react with anti-A2 lectin

d. The patient's serum will react with A1 cells if

anti-A1 is present

d. the patients serum will react with A1 cells if anti-A1 is present

The A2 subgroup is described as having both qualitative

and quantitative differences when compared

to the A1 subgroup. This means that there

is less A antigen found on the red cells of people

with A2, and their A antigen looks "different"

when compared to that of people with type A1.

Therefore the red cells from those with type A2

will not react with anti-A1 lectin. Approximately

20% of those with type A have the A2 phenotype,

and between 1% and 8% of those individuals

make anti-A1. There is no anti-A2 reagent, and

people with the A2 phenotype would not react

with A2 cells, because that would imply an autoantibody

is present.

Which genotype confers the Bombay blood type?

a. Hh

b. hh

c. Sese

d. Lele

b. hh

People with the Bombay phenotype do not

express the H antigen. An individual with the

hh genotype would not express H antigen.

Which genes encode for Rh antigens?

a. RHDCE

b. RHD

c. RHCE

d. Both b and c

d. both b and c

The RHD gene encodes for the D antigen.

The RHCE gene determines C, c, E, and e specificities.

Therefore the correct answer must include

both genes.

Testing for the D antigen was conducted at the IAT

phase. A control was included in the testing. Both

the patient's red cells and the control tube reacted

at 4+. How would you interpret this test?

a. The test is invalid because the control tube was

positive

b. The patient is D positive

c. The patient is D negative

d. The test should be repeated and the control tube

omitted

a. The test is invalid because the control tube was positive

In indirect antiglobulin test (IAT) phase, a control

tube is included to show that agglutination

detected in the patient test tube is appropriate.

In weak D testing, the control tube uses saline

rather than anti-human globulin (AHG) reagent.

Agglutination in the control tube suggests that

the patient cells are already sensitized with immunoglobulin,

so a positive reaction in the patient

test tube should be invalidated and investigated.

Of the red cells listed, which has the most D antigen

present?

a. Rh null

b. D positive

c. dce/dce

d. D--

d. D—

Individuals with the D phenotype may possess

more D antigen because they have inherited a nonfunctioning

RHCE gene. Basically, the RHD gene

ofDindividualshasnocompetitionwhenbuilding

D antigen, so they end up with more. Rh-null

individuals do not express any Rh antigens. Dpositive

individuals possess theDantigen, butwithout

knowing the genotype, theamount ofDantigen

cannot be estimated. A person with the dce/dce

genotype would be considered Rh-negative.

Which is true of the Duffy blood group system?

a. Antigens are resistant to enzyme treatment

b. Antibodies never show dosage

c. Fya and Fyb are codominant alleles

d. The majority of whites are Fy(a-b-)

c. Fya and Fyb are codominant alleles

The Duffy blood group system contains two

codominant alleles, Fya and Fyb, as well as Fy3,

Fy5, and Fy6. The Fya, Fyb , and Fy6 antigens

are sensitive to ficin, and antibodies made against

the Duffy antigens can show dosage. Approximately

68% of the black population is Fy(ab).

Which antibody is typically considered to be an autoantibody

if found in the serum of an adult?

a. Anti-K

b. Anti-I

c. Anti-D

d. Anti-Fya

b. Anti-I

The I antigen is a precursor to the H antigen, so

individuals who express the H antigen are presumed

to have the I antigen. Therefore, if an individual

expresses anti-I, it is typically considered

to be an autoantibody. Anti-I typically presents

as a cold-reacting, clinically insignificant IgM

autoantibody.

Which reagent destroys all of the Kell blood group

system antigens?

a. DTT

b. Chloroquine diphosphate

c. AHG

d. LISS

a. DTT

Dithiothreitol (DTT) disrupts the tertiary structure

of proteins, and denatures the Kell system antigens

on red cells. Chloroquine diphosphate (CDP) can

be used to dissociate antibodies from red cells.

Anti-human globulin (AHG) reagent is used in

the indirect antiglobulin test (IAT). Low ionic

strength solution (LISS) is used as a potentiator.

Which is true of antibodies to Kidd blood group system

antigens?

a. They are enhanced by enzymes

b. Titers can quickly drop in patients

c. Both A and B

d. None of the above

c. Both A and B

The Kidd blood group system contains three antigens,

Jka, Jkb, and Jk3. Antibodies made against

this blood group system are typically IgG, are best

detected by indirect antiglobulin test (IAT), are

enhanced by treating reagent red cells with

enzymes, and can show dosage. Antibody titers

have also been found to increase and then quickly

decrease in patients.

Which of the following is true of the Lewis system?

a. Lewis antigens are found on type II precursor cells

b. Lewis antigens are well developed at birth

c. Antibodies to Lewis antigens always cause HTRs

d. Antibodies to Lewis antigens rarely cross the

placenta

d. Antibodies to Lewis antigens rarely cross the placenta

The Le gene adds fucose to either a type I precursor

chain to make the Lea antigen or adds fucose

to the H structure to make Leb. Type II chains

never express Lewis antigen activity. Newborns

express the Le(ab) phenotype. Antibodies

against the Lewis antigens are typically roomtemperature

(RT) reactive, IgM class, and not clinically

significant. Because they are typically IgM

class, they cannot cross the placenta.

Which of the following is true of antibodies to MNS

blood group system antigens?

a. Anti-U is directed at a high-incidence antigen

b. Anti-N is commonly found

c. Anti-M is always clinically significant

d. Anti-S is reactive with enzyme-treated cells

a. Anti-U is directed at a high incidence antigen

The U antigen is located near the red membrane on

glycophorin B (GYB), so is always present when S

or s is inherited. The amino acid structure on GYB

is the same as the first 26 amino acid sequence on

glycophorin A (GYA), so the only individuals who

can make anti-N are those who lack GYB. Anti-M

is typically an IgM class antibody, usually considered

to be clinically insignificant. The effect of

enzymes on the S antigen is variable.

Which of the following antibodies is classified as

"biphasic" and an autoantibody?

a. Anti-B

b. Anti-P

c. Anti-H

d. Anti-Lea

b. Anti-P

Allo-anti-P is a rare antibody made by individuals

with the P2

k phenotype, somost examples of anti-P

seen in the blood bank are actually autoanti-P.

Autoanti-P is associated with paroxysmal cold

hemoglobinuria. This antibody is an IgG antibody, also called the Donath-Landsteiner antibody. It is a

biphasic hemolysin that attaches to P-positive red

cells at lower temperatures. Complement is

attached, and when the red cells are warmed to

37 C, hemolysis occurs. The other antibodies

listed are typically RT reactive antibodies.

You have performed an antibody screen using the

tube method. All three screening cells tested negative.

The Coombs check cells in all three tubes are also

nonreactive. What should you do?

a. Respin the tubes and reread them

b. Report the antibody screen as negative

c. Repeat the antibody screen

d. Perform an antibody identification panel

c. Repeat the antibody screen

Coombs check cells are used to verify that antihuman

globulin (AHG) has been added to reagent

tubes and that it is active. When the check cells do

not agglutinate, either AHG was not added or it

was somehow inactivated. This usually occurs

because of inadequate washing. If the check cells

do not work, the entire test should be repeated.

An antibody panel has six 2+ reactive cells at AHG

phase. Panel testing using enzyme-treated cells

showed no reactivity. Which is the most likely antibody

that is present?

a. Anti-Fya

b. Anti-e

c. Anti-k

d. Anti-Lua

a. Anti-Fya

Because enzyme treatment removed the reactivity

noted in the original panel, we can infer that the

unexpected antibody is directed to an antigen that

is sensitive to enzymes. Of the antigens given in the

list, only the Fya antigen is sensitive to enzymes.

A patient has a currently nonreactive antibody screen

but has a history of anti-Jka in the patient file. Which

type of crossmatch must be performed on this patient?

a. Immediate spin crossmatch

b. IAT crossmatch

c. Electronic crossmatch

d. Both a and c

b. IAT crossmatch

Whenever an unexpected antibody is currently

reactive or noted in a patient's history file, an indirect

antiglobulin test (IAT) crossmatch must be

performed. An immediate spin or electronic crossmatch

is performed only on patients with no evidence

of clinically significant antibodies,

currently and historically.

A recently transfused patient has a 3+ reactive DAT

with anti-IgG. Which procedure should be used to

identify the specificity of the IgG antibody attached

to the red cells?

a. Adsorption

b. Neutralization

c. Titration

d. Elution

d. Elution

A positive direct antiglobulin test (DAT) implies

that the patient has an IgG antibody attached to

the red cells. An elution procedure would dissociate

the antibody from the red cells and collect it so

the specificity can be determined. An adsorption

removes red cell antibodies from plasma by

adsorbing antibody onto red cells. Neutralization

is performed to inactivate an antibody present in

plasma. A titration is performed to determine

how much antibody is present in plasma.

An O-negative mother gave birth to an O-positive

baby. Her rosette test was positive. Which of the following

is true?

a. The test is invalid because of the mother's

ABO type

b. A Kleihauer-Betke test should be performed to

quantify the fetal maternal hemorrhage

c. The mother should be given a 300-mg dose

of RhIG

d. A weak D test should be performed on the baby

b. A Kleihauer-Bette test should be performed to quantify the fetal maternal hemorrhage

A positive rosette test is a qualitative indicator that

a fetal bleed has occurred. This is important to

detect in Rh-negative mothers who have an Rhpositive

baby. To provide the correct dosage of

Rh immunoglobulin, a quantitative test must be

performed to quantify the amount of bleed that

occurred. The Kleihauer-Betke test looks for fetal

hemoglobin in a sample collected fromthe mother.

In which of the following settings are platelet transfusions

not indicated?

a. Thrombotic thrombocytopenic purpura

b. Immune thrombocytopenic purpura with severe

intracranial hemorrhage

c. Massive transfusion

d. Vascular catheter placement, platelet count

24,000/mL

e. Brain biopsy, platelet count 62,000/mL

a. Thrombotic thrombocytopenic purpura (TTP)

is characterized by thrombocytopenia, microangiopathic

hemolytic anemia, renal dysfunction, and

central nervous system involvement. Basically,

giving platelets to a patient with TTP provides

fuel that would exacerbate the condition. The

other conditions listed are all appropriate indicators

for platelet transfusion.

An obstetric patient presents to the hospital with

marked vaginal bleeding and severe lower abdominal

pain. During placement of an intravenous catheter,

she was noted to have marked oozing. She is diagnosed

with disseminated intravascular coagulation

as a complication of her primary problem. She is

given cryoprecipitate and fresh frozen plasma before

going to the operating room. What element of cryoprecipitate

is important in treating this patient?

a. Factor I

b. Factor II

c. Factor VIII:c

d. Factor VIII:vWF

e. Factor XIII

a. Factor I

In disseminated intravascular coagulation, platelets

and fibrinogen are inappropriately consumed,

and so transfusion therapy should be targeted

toward replacing those elements. Cryoprecipitate

contains in a concentrated form most of the coagulation

factors found in fresh frozen plasma.

These include von Willebrand factor, fibrinogen

(I), factor VIII, fibronectin, and factor XIII. Cryoprecipitate

is primarily used clinically for patients

with deficiencies of factor XIII and fibrinogen.

A patient's ABO blood type is determined by which

of the following?

a. Genetic inheritance and environmental factors

b. Genetic inheritance

c. Environmental factors

d. Immune function

e. Maternal blood type

b. Genetic inheritance

The best answer to this question is genetic inheritance,

which includes but is not limited to the

mother's blood type. Inheritance of the ABO antigens

are driven by the ABO, H, and Se genes.

Genetic inheritance, environmental factors, and

immune function would influence the presence

of antibodies against certain ABO antigens.

A trauma patient with type AB is seen at a rural hospital.

The hospital only has 3 units of type AB RBCs.

What blood type of RBCs can the patient receive as

an alternative?

a. Type O

b. Type B

c. Type A

d. None of the above

e. All of the above

e. All of the above

The patient can receive all of the blood types listed,

but good blood management would dictate the

order in which they were transfused. Generally,

the best course of action would be to transfuse type

A first because it is usually more plentiful than type

B. Patients with O type can receive only type O

blood, so it is best to conserve type O when possible.

If type A is not plentiful, type B can be given.

Once either type A or type B is given, types should

not be mixed, to help avoid potential reactions. If

type A or B is exhausted, it is then appropriate to

move to type O.

A genetic state in which no detectable trait exists is

called:

a. Recessive

b. Dominant

c. Incomplete dominance

d. Amorph

d. Amorph

An amorph, or silent, gene does produce a detectable

antigen product. Examples of amorph, or

null, phenotypes include Rhnull, O, and Lu

(ab).

Most blood group antigens are expressed as a result

of which of the following?

which of the following?

a. Autosomal recessive inheritance

b. X-linked dominant inheritance

c. Y-linked recessive inheritance

d. Autosomal codominant inheritance

d. Autosomal codominant inheritance

Most blood group systems genes exhibit codominant

expression, or equal expression of both

traits. In an autosomal recessive inheritance pattern,

a trait is observable only when not paired

with a dominant allele. X-linked and Y-linked

inheritance patterns are complex and not typically

seen in most blood group systems.

What blood type is not possible for the offspring of

AO and BO parents?

a. AB

b. A or B

c. O

d. All are possible

d. All are possible

This answer is best explained through the use of a

Punnett square

How many molecules of IgM are needed to fix

complement?

a. 1

b. 2

c. 3

d. 4

a. 1

IgM is classified as having a large pentamer structure.

Thus only one IgM is required to initiate the

classical pathway in the complement system. In

comparison, it takes two IgG molecules to activate

complement.

For lysis of red blood cells to occur after antigen-

antibody reaction, which compound is required?

a. Albumin

b. Glucose-6-phosphate dehydrogenase (G6PD)

c. Complement

d. Antihuman globulin (AHG)

c. Complement

In vitro, complement is detected through the use

of anti-C3b or anti-C3d reagents. When detected,

this indicates complement proteins have been

attached to the red cell surface as a result of the

activation of complement's classical pathway.

In vivo, complement activation may proceed to

intravascular hemolysis if conditions are right,

which would result in the lysis of red blood cells.

An end-point of tube testing other than agglutination

that must also be considered a positive reaction is

called:

a. Clumping

b. Mixed field

c. Hemolysis

d. Microscopic

c. Hemolysis

Hemolysis as a reaction end-point indicates the

presence of a complement-activating antibody.

This reaction is especially important to recognize

because it is an indicator of an antigen-antibody

reaction. When hemolysis occurs, the red cell button

is often smaller than buttons in other tubes

and the supernatant may appear to be pinkish

or reddish.

Mixed-field (mf) agglutination can be observed

in the:

a. DAT on a person undergoing delayed hemolytic

transfusion reaction

b. IAT result of a patient who has anti-Lea

c. DAT on a patient on high doses of penicillin

d. Typing result with anti-A of a patient who is A2

subgroup

a. DAT on a person undergoing delayed hemolytic transfusion reaction

Mixed-field (mf) agglutination indicates the presence

of two red cell populations when noted: one

that is agglutinating, and one that is not. Of the scenarios

presented, a person undergoing a delayed

hemolytic transfusion reaction is most likely to

have two cell populations in circulation—his/her

own red cells and those from the transfusion. In

a delayed transfusion reaction, an antibody has

been stimulated against the transfused cells. A positive

direct antiglobulin test (DAT) in this scenario

indicates the antibody has attached to the transfused

cells but not to the patient's own cells; therefore

mixed-field reactivity is noted.

In which situation(s) may the ABO serum grouping

not be valid?

a. The patient has hypogammaglobulinemia

b. IgM antibodies are present

c. Cold autoantibodies are present

d. All of the above

d. All of the above

Patient's with hypogammaglobulinemia have an

overall reduction of g-globulins and may not be

able to reverse grouping antibodies at levels detectable

by ABO typing tests. IgM antibodies, other

than those normally detected in reverse grouping

tests, or cold autoantibodies may interfere with

reverse grouping tests, making the results invalid.

One example of an IgM antibody that may interfere

with reverse grouping is anti-M.

If you knew the DAT is positive, what would you

expect the Rh control to be when doing a weak D test

through AHG?

a. Negative

b. Positive

c. Mixed field

d. Hemolysis at 37 C would be seen

b. Positive

Cells that are direct antiglobulin test (DAT)-

positive or already have IgG attached would give

a false-positive reaction when tested by the indirect

antiglobulin test (IAT). The IAT is used to

detect antibody bound to red cells in vitro. IAT

is a two-stage procedure. In the first stage, antibodies

are encouraged to combine with their corresponding

antigen during an incubation step. If

DAT-positive red cells (cells that have antibody

already attached) are used in an IAT test, the first

step, in effect, has already occurred. The attached

IgG molecules will be detected in the second IAT

step, the agglutination step, and give a falsepositive

reaction.

How can IgG antibodies be removed from red cells?

a. Elution

b. Adsorption

c. Prewarming

d. Neutralization

a. Elution

An elution is a process that dissociates antigen-

antibody complexes on red cells. An adsorption

is a process that uses red cells to remove red cell

antibodies from a solution. Prewarming is a technique

in which all reagents and patient samples

used in a test procedure are incubated to reach

37 C (or the preferred testing temperature)

before the test is conducted. Neutralization combines

a soluble antigen with antibody in vitro and

is used as an antibody identification technique.

Therefore the best answer is elution.

Testing needs to be done with an antiserum that is

rarely used. The appropriate steps to take in using this antiserum include following the manufacturer's

procedure and:

a. Performing a cell panel to be sure that the antiserum

is performing correctly

b. Performing the testing on screen cells

c. Testing in duplicate to ensure the repeatability of

the results

d. Testing a cell that is negative for the antigen and

one that is heterozygous for the antigen

d. Testing a cell that is negative for the antigen and one that is heterozygous for the antigen

Before a reagent is used, it should be assessed to

determine if it meets preset acceptable performance

criteria. For a red cell antiserum, an example

of acceptable performance criteria might

include reactivity with antigen-positive cells and

no reactivity with antigen-negative cells. When

testing antigen-positive cells, cells with heterozygous

inheritance are generally recommended for

use because this would detect the weakest expression

of antigen (single-dose).

(see pic) Based on the following antigram, which cell is heterozygous

for M?

a. Cell 1

b. Cell 2

c. Cell 3

d. None of the above

a. Cell 1

M and N are antithetical alleles in the MNS system.

A cell with heterozygous expression of the

M antigen would therefore need to also express

the N antigen. In other words, it would need to

beM+N+. Cells that express onlyMor N antigen

(M+N or MN+) would be presumed to be

homozygous for either the M or N antigen,

respectively.

Which antibody can be neutralized with a specific

reagent?

a. Anti-D

b. Anti-Jka

c. Anti-M

d. Anti-Lea

d. Anti-Lea

Neutralization combines a soluble antigen with

antibody in vitro and is used as an antibody identification

technique. Commercially prepared Lewis

substance is available for purchase, so of the list

provided, only anti-Lea could be neutralized.

Group O red blood cells are used as a source of commercial

screening cells because:

a. Anti-A is detected using group O cells

b. Anti-D reacts with most group O cells

c. Weak subgroups of A react with group O cells

d. ABO antibodies do not react with group O cells

d. ABO antibodies do not react with group O cells

O red blood cells possess only the H antigen,

andOred cells used for reagent purposes typically

also lack D antigen. O-negative reagent red

cells do not react with anti-D or any ABO

antibodies.

The use of EDTA samples for the direct antiglobulin

test prevents activation of the classical complement

pathway by:

a. Causing rapid decay of complement proteins

b. Chelating Mg2+ ions, preventing assembly of C6

c. Chelating Ca2+ ions, preventing assembly of C1

d. Preventing chemotaxis

c. Chelating Ca2+ ions, preventing assembly of C1

Ethylenediaminetetraacetic acid (EDTA) chelates

calcium ions to form a soluble complex; therefore

it prevents the assembly of C1.

Check (Coombs control) cells are:

a. Added to every negative antiglobulin test

b. Added to negative direct antiglobulin tests only

c. Used to confirm a positive Coombs' reaction

d. Coated with both IgM and C3d

a. Added to every negative antiglobulin test

IgG-sensitized red cells (check cells or Coombs

control cells) are commercially prepared with

IgG antibodies attached. Proper control of antihuman

globulin (AHG) tests systems (indirect

antiglobulin test [IAT] or direct antiglobulin test

[DAT]) require check cells to be added to negative

tubes to ensure that AHG reagent was added and

is active.

What type(s) of red cells is(are) acceptable to transfuse

to an AB-negative patient?

a. A negative, B negative, AB negative, O negative

b. O negative only

c. AB negative only

d. AB negative, A negative, B negative only

a. A negative, B negative, AB negative, O negative

People with the AB blood type are considered to

be universal recipients because they possess all

possible ABO antigens; therefore they do not

make any antibodies to ABO antigens. People

with AB who are also negative for the D antigen

may receive any type of blood as long as they have

not made an antibody against the D antigen.

A nonbleeding adult of average height and weight

with chronic anemia is transfused with 2 units of

red blood cells. The pretransfusion Hgb is 7.0 g/dL.

What is the expected posttransfusion Hgb?

a. 8 g/dL

b. 9 g/dL

c. 10 g/dL

d. 11 g/dL

b. 9 g/dL

Transfusing 1 unit of red cells usually increases

the hemoglobin (Hgb) by approximately 1 g/dL.

Therefore transfusing 2 units of red cells to a

patient not actively bleeding should increase the

pretransfusion Hgb by 2 g/dL.

An IgA-deficient patient with clinically significant

anti-IgA requires which of the following?

a. Leukocyte-reduced fresh frozen plasma

b. CMV-seronegative RBCs

c. Irradiated RBCs and platelets

d. Washed RBCs

d. Washed RBCs

A patient with IgA deficiency and clinically significant

anti-IgA requires washed red blood cells if a

transfusion is necessary, because washing

removes plasma proteins. It should be noted that

washing is associated with a loss of about 10% to

20% of the original unit.

Anti-H will react weakest with blood from a person

with _____________.

a. Group O

b. Group A1

c. Group A2

d. Group A2B

b. Group A1

Of the types listed, the enzyme that converts

H antigen to A1 antigen is the most active. Therefore

group A1 has very little unconverted H antigen.

The order of blood types possessing the most

H antigens to the fewest H antigens is O>A2>

B>A2B>A1>A1B.

Which of the following antibodies do not match the

others in terms of optimal reactive temperature?

a. Anti-Fya

b. Anti-M

c. Anti-K

d. Anti-S

b. Anti-M

Anti-Fya, anti-K, and anti-S all preferentially react

at the anti-human globulin (AHG) phase. Although

anti-M also can be found to react at the AHG

phase, many examples react only at room temperature

(RT) phase.

What antibody can an R1r patient make if transfused

with R2R2 blood?

a. Anti-D

b. Anti-C

c. Anti-E

d. Anti-c

e. Anti-e

c. Anti-E

A patient with R1r possesses D, C, c, and e antigens.

R2R2 blood possesses D, c, and E antigens.

To determine what antibodies could be made on

exposure, determine what is different between

the two, or what foreign antigen could be introduced

to the patient. In this case, the E antigen

would be foreign and could potentially stimulate

antibody production.

What is the probability of finding blood negative for

the Jka and Fya antigens (23% of population is Jk

[a] and 34% of population is Fy[a])?

a. 5.1%

b. 51%

c. 7.8%

d. 78%

c. 7.8%

To determine the combined phenotype for blood

negative for the Jka and Fya antigens, multiply the

percentages of person negative for each antigen.

0:23 x 0:34 = 0.0782 or 7.8%

(see pic) If the following patient's RBCs were tested against

anti-H lectin and did not react, this person would

be identified as a(an):

a. Acquired B

b. Secretor

c. Oh phenotype

d. Subgroup of A

c. Oh phenotype

Persons of the Oh phenotype (Bombay) type as

group O, but also possess potent anti-H. This

anti-H is usually detected in tests using group O

cells (antibody screen or crossmatch), but may

be noted in ABO grouping, because the reverse

cells could be hemolyzed instead of just

agglutinated.

If a person has the genetic makeup Hh, AO, LeLe,

sese, what substance will be found in the secretions?

a. A substance

b. H Substance

c. Lea substance

d. Leb substance

c. Lea substance

• Hgene: Produces Hantigen on type II chains in

secretions and H antigen on red cells

• A gene: Encodes for a glycosyltransferase that

produces A antigen

• O gene: Silent gene

• Le gene: Encodes for a fucosyltransferase that

produces Lea antigen

• se gene: Amorph allele; inheriting two se genes

means that the person is a nonsecretor

Le and secretor gene interaction: If Le is inherited

without Se, only Lea will be found on red

cells and in saliva. Because this person is a nonsecretor,

only Lea antigen will be present in the

secretions.

Before A and B antigens can be expressed, the precursor

substance must have the terminal sugar

_______________.

a. d-Galactose

b. N-Acetylgalactosamine

c. Glucose

d. L-Fucose

d. L-Fucose

N-Acetylgalactosamine (GalNAc) confers type A

specificity. D-Galactose (Gal) confers type B

specificity. L-Fucose (Fuc) confers type O specificity.

The type A and type B sugars are built

on Fuc.

A white female's RBCs gave the following

reactions: D+, C+, E-, c+, e+. The most probable

Rh genotype is:

a. DCe/Dce

b. DCe/dce

c. DCe/DcE

d. Dce/dCe

b. DCe/dce

The DCe/dce (R1r) phenotype is found in approximately

35% of whites and 15% of blacks.

Although DCe/Dce (R1Ro) and DCe/dCe (R1r0)

are also possibilities, they are statistically less

probable than DCe/dce. It is not possible for this

person to be DCe/DcE, because she tested negative

for the E antigen.

If a D-positive person makes anti-D, this person is

most likely:

a. Partial D

b. D negative

c. Weak D as position effect

d. Weak D because of transmissible genes

a. Partial D

Individuals who inherit the D antigen with weakened

or missing epitopes are described as having

partial D antigen and often present with weakened

expression of the D antigen. Because the partial

D antigen is essentially incomplete, if an

individual with partial D antigen is exposed to

complete D antigen, the person would theoretically

be able to make an alloantibody against

the parts of the antigen that were foreign.

A serum containing anti-k is not frequently encountered

because of which of the following?

a. People who lack the k antigen are rare

b. People who possess the k antigen are rare

c. The k antigen is not a good immunogen

d. Kell-null people are rare

a. People who lack the k antigen are rare

The k antigen is present in 98.8%of white individuals

and 100% of black individuals, so it would be

very rare to encounter someone who lacked the k

antigen.

A characteristic of the Xga antigen is that the Xga

antigen:

a. Has a higher frequency in women than in men

b. Has a higher frequency in men than in women

c. Is enhanced by enzymes

d. Is usually a saline reacting antibody

a. Has a higher frequency in women than in men

Expression of the Xga antigen is controlled by an

X-linked gene, and prevalence of the antigen is

higher in females than in males. Anti-Xga is usually

IgG and the Xga antigen is sensitive to ficin.

Which of the following is a characteristic of the Kidd

system antibodies?

a. The antibodies are usually IgM

b. The corresponding antigens are destroyed by

enzymes

c. The antibodies are usually strong and stable during

storage

d. The antibodies are often implicated in delayed

hemolytic transfusion reactions

d. The antibodies are often implicated in delayed hemolytic transfusion reactions

Kidd system antibodies are usually IgG, are

enhanced by enzymes, and do not store well.

The titer of Kidd system antibodies in individual

patients can rise and fall quickly, meaning that

they might not be detected in an antibody screen

if the titer is below the detection point of the test

system.

Anti-E will react with which of the following cells?

a. RoRo

b. R1R1

c. R2R2

d. rr

c. R2R2

• RoRo=Dce/Dce

• R1R1=DCe/DCe

• R2R2=DcE/DcE

• Rr=dce/dce

Therefore anti-E will react only with R2R2 cells

because they are the only ones in this list that possess

the corresponding E antigen.

Which statement is not true concerning anti-Fya and

anti-Fyb?

a. Are clinically significant

b. React well with enzyme-treated panel cells

c. Cause hemolytic transfusion reactions

d. Cause a generally mild hemolytic disease of the

newborn

b. React well with enzyme-treated panel cells

Antibodies to Duffy system antigens are clinically

significant (associated with hemolytic transfusion

reactions) and have typically been shown to

cause mild hemolytic disease of the fetus and

newborn (HDFN). Because the Fya and Fyb antigens

are sensitive to enzymes, anti-Fya and

anti-Fyb would not react with enzyme-treated

panel cells.

Which of the following antibodies can be neutralized

with pooled human plasma?

a. Anti-Hy and anti-Ge:1

b. Anti-Cha and anti-Rga

c. Anti-Coa and anti-Cob

d. Anti-Doa and anti-Jsb

b. Anti-Cha and anti-Rga

Anti-Ch and anti-Rg are usually IgG and react

weakly. Neutralization of these two antibodies

with pooled plasma is often used as part of antibody

identification when either or both antibodies

are present.

Donors who have received RBC transfusion within

the last 12 months are deferred because:

a. Blood could transmit hepatitis or HIV

b. Donor red cell hemoglobin level may be too low

c. Donor health would prohibit the donation

process

d. There will be two cell populations in this

donor

a. Blood could transmit hepatitis or HIV

Potential donors who have been transfused in

the last 12 months are deferred because of the possibility

of exposure to diseases. Although viral

marker testing has increased the safety of the

blood supply, some diseases have a window in

which markers are below the threshold of

detection.

Autologous presurgical donations are not allowed

for which of the following patients?

a. Weigh less than 100 lb

b. Under the age of 14

c. With hemoglobin of 13 g/dL

d. With bacteremia

d. With bacteremia

For autologous donors who weigh less than

100 lb, the volume of blood collected and the

amount of anticoagulant used should be proportionately

less when compared to a donation

from a person weighing more than 110 lb. There

is no age restriction for autologous donors.

Hgb concentration in a potential autologous

donor should be no less than 11 g/dL. Therefore

the only condition that would preclude donation

is current bacteremia. Blood collected while a

patient is septic could cause harm if

transfused later.

Which of the following viruses resides exclusively in

leukocytes?

a. HCV

b. HBV

c. CMV

c. CMV

Cytomegalovirus (CMV) can be transmitted

through transfusion via intact white cells contained

in cellular blood products. Leukoreduction

of blood products reduces the risk for

CMV transmission because the CMV virus

resides within intact white cells.

Which product is least likely to transmit hepatitis?

a. Cryoprecipitate

b. Plasma protein fraction

c. RBC

d. Platelets

b. Plasma protein fraction

(PPF) is prepared from

large pools of human plasma. Although PPF

can transmit infectious agents, the risk for doing

so is reduced because certain viruses are inactivated

or removed during preparation. Of the components listed, PPF is the only component

treated in this manner.

In preparing platelets from a unit of whole blood, the

correct order of centrifugation is:

a. Hard spin followed by a hard spin

b. Light spin followed by a light spin

c. Light spin followed by a hard spin

d. Hard spin followed by a light spin

c. Light spin followed by a hard spin

To prepare platelets, whole blood is first centrifuged

at a light spin, and platelet-rich plasma is

expressed off the red cells into a satellite bag. The

platelet-rich plasma is then centrifuged at a hard

spin, and plasma is expressed off of the platelets.

Which antibody could cause hemolytic disease of the

fetus and newborn?

a. Anti-I

b. Anti-K

c. Anti-Lea

d. Anti-N

b. Anti-K

Of the antibodies in this list, anti-K is the one

most likely to be IgG and able to cross the placenta.

Anti-I, anti-Lea, and anti-N typically present

as IgM class antibodies when encountered

in patient specimens.

A group A, D-negative obstetric patient with

anti-D (titer 256) is carrying a fetus who needs an

intrauterine transfusion. The blood needed

should be:

a. Group A, D-negative RBC

b. Group A, D-negative whole blood

c. Group O, D-negative RBC

d. Group O, D-negative whole blood

c. Group O, D-negative RBC

Group O red cells are most generally used for

intrauterine and neonatal transfusions. Rhnegative

blood is used for fetuses and neonates

when the blood type is unknown or Rh-negative.

In this case, because the mother has anti-D, Rhnegative

blood must be used for the intrauterine

transfusion.

Which of the following mothers should receive

RhIG?

a. A-negative mother; O-negative baby; no prenatal

care, anti-D in mother

b. AB-negative mother; B-positive baby; anti-D

in mother

c. O-negative mother; A-positive baby; no anti-D

in mother

d. A-positive mother; A-positive baby; no anti-D

in mother

c. O-negative mother; A-positive baby; no anti-D in mother

Rh immunoglobulin (RhIG) is given to D-negative

mothers to prevent the formation of anti-D. If a

mother has already formed anti-D, then RhIG will

offer no protection.

How many doses of RhIG are indicated for a

Kleihauer-Betke reading of 0.6%?

a. 1

b. 2

c. 3

d. 4

b. 2

To quantify the amount of fetomaternal hemorrhage

(FMH), the percentage of fetal red cells

counted is multiplied by the mother's blood

volume. The mother's blood volume can be calculated

based on her height and weight, but

often the average of 5000 mL is used for

calculation.

0.6/100 = 5000 mL = 30 mL

What should be done first if a mother types as O and

the baby types as AB?

a. Report the results with no further testing

b. Try to get a sample from the father

c. Recheck all labels, get new samples, if necessary,

and retest

d. Retype using all new reagents

c. Recheck all labels, get new samples, if necessary, and retest

An O mother (genotype OO) would contribute

an O gene to her child, so regardless of the

father's type, an O mother could not have an AB

child. A clerical error has likely occurred and

should be eliminated as a cause of potential

error before further serologic studies are conducted.

A newborn has a positive DAT.What is the best procedure

to determine the antibody causing a positive

DAT in this newborn?

a. An antibody titer on the mother's serum

b. An antibody panel on the mother's serum

c. An antibody panel performed on the eluate of the

mother's cells

d. An antibody panel performed on the eluate of the

baby's cells

b. An antibody panel on the mother's serum

Any antibody attached to a baby's red cells

would have to come from the mother. Sample

from the mother is easily acquired and should

be readily available. Although an eluate could

be performed on the baby's cells, that is a timeconsuming

procedure requiring a large sample.

The best procedure is to perform an antibody

panel on the mother's serum.

Which of the following is(are) an example(s) of a

record-keeping error?

a. Use of correction fluid or tape

b. Using pencil

c. Documentation after the fact

d. All of the above

d. All of the above

Use ofwhiteout obliterates the original results, so is

not allowed. Use of pencil results in a record that

could be changed—that is, the record is not permanent. If it is not recorded, it did not happen,

so documentation after the fact is not allowed.

Which of the antigens below is considered low

incidence?

a. Fya

b. S

c. C

d. Kpa

d. Kpa

is an antigen in the Kell system that is present

in 2% of whites and found only rarely in blacks.

Which of the antigens below is considered high

incidence?

a. Fyb

b. Vel

c. E

d. S

b. Vel

is an antigen of high prevalence. Vel exhibits

variable antigen expression on red cells and is

resistant to treatment with enzymes.

In performing tube testing, you see many mediumsized

agglutinates in a clear background. How would

you grade this reaction?

a. 2+

b. 1+

c. 4+

d. 3+

a. 2+

A 1+ reaction has numerous medium and

small agglutinates with a turbid background. A

2+ reaction has many medium-sized agglutinates

with a clear background. A 3+ reaction has several

large agglutinates and a clear background.

A 4+ reaction has a solid agglutinate with a clear

background.

Of the following, which genotypes would result in

the B phenotype?

a. BB

b. AB

c. BO

d. a and b

e. a and c

e. a and c

A and B genes in the ABO system have codominant

expression, and the O gene is a silent allele,

producing no detectable gene product. For an

individual to have a B phenotype, a B gene needs

to be inherited either in a homozygous fashion or

along with an O gene.

(see pic) How would you interpret the following reactions?

a. Blood type A

b. Blood type O

c. Blood type B

d. Blood type AB

b. Blood type O

The forward type shows no agglutination, meaning

the individual does not possess A or B antigens.

The reverse type shows reactivity with

both A1 and B cells, meaning the individual possess

antibodies to A and B antigens. This is characteristic

of the O blood group.

(see pic) Noting these reactions, if they patient needed blood

now, what type of blood should be transfused?

a. Blood type A

b. Blood type O

c. Blood type A2

d. Blood type A

b. Blood type O

This patient forward types as group A and reverse

types as group O, so an ABO discrepancy is present.

In the event that the patient needs blood

before the discrepancy can be resolved, group O

must be transfused.

Blood group antibodies made by type A and type B

people are predominantly which class?

a. IgE

b. IgA

c. IgG

d. IgM

d. IgM

Group A and B individuals predominantly make

IgM ABO antibodies, but small quantities of

IgG antibody can be seen. Group O individuals

tend to make predominantly IgG ABO antibodies.

This is important to understand why ABO hemolytic

disease of the newborn is more commonly

seen in group O mothers.

(see pic) Based on these reactions, what should be the next step?

a. Test the serum with A2 cells

b. Report the patient as type A

c. Test the cells with anti-A1 lectin

d. Both a and c

e. Request a new specimen

d. Both a and c

This patient forward types as group A and reverse

types as group O, so an ABO discrepancy is present.

You could not report out results until the discrepancy

was explained. The A1 cells are reacting only at 1+ strength, so this points to possible extra

reactivity in the reverse type. Extra reactivity in

the reverse type can be caused by rouleaux,

cold-reactive antibodies (autoantibody or alloantibody),

or passively acquired antibodies. In the

case of a group A individual showing weak reactivity

with A1 cells, this is often seen in group A2

individuals who have made anti-A1. Testing the

cells with anti-A1 lectin would tell us if the patient

possesses A1 antigen, and testing the serum with

A2 cells would tell us if the extra reactivity noted

in the reverse type is likely caused by anti-A1. If

the discrepancy could not be resolved, it would

be advisable to request a new specimen.

A "directed donor" unit of blood is defined as a unit

of blood from a person who gives blood for:

a. Relief of polycythemia or other blood disorder

b. His or her specific use only

c. First-degree blood relative

d. Another person he or she has specified

d. Another person he or she has specified

A directed unit is donated for a specific person

identified by the donor. This is not limited to

blood relatives. A therapeutic phlebotomy is performed

on individuals with polycythemia or other

blood disorders, as ordered by a physician. When

an individual donates blood for his or her own

use, this is called an autologous donation.

Before the patient can receive a directed donation

unit, the patient requires which of the following tests

to be completed?

a. Type and screen only

b. Type and screen and compatibility testing

c. Retype of patient and donor unit

d. No additional testing is required

b. Type and screen and compatibility testing

The only difference between a directed donation

and a volunteer donation is that a directed donation

is reserved for a specified individual. Testing

for transfusion of a directed unit is no different

from that conducted on a volunteer unit intended

for transfusion.

An 18-year-old female with a hematocrit of 38%,

temperature of 37 C, and blood pressure of 175/

90 mm Hg presents for whole blood donation. Based

on this information, would you accept, permanently

defer (PD), or temporarily defer (TD) the donor?

a. Accept

b. TD, blood pressure is too high for a person of

her age

c. TD, temperature is too high

d. PD, for all values listed

a. Accept

Allogeneic donors must meet the following physical

examination criteria before donation: (see pic)

A 63-year-old man with a hemoglobin value of

130 g/dL and pulse of 80 beats/min, who received

human pituitary growth hormone (PGH) when he

was 10 years old, presents for whole blood donation.

Based on this information, would you accept, permanently

defer (PD,) or temporarily defer (TD) the donor?

a. Accept the donor

b. TD, because of the human PGH

c. PD, because of the human PGH

d. PD, because of the high hemoglobin value

c. PD, because of the human PGH

Receipt of human pituitary growth hormone

(PGH) requires indefinite or permanent deferral

because of the theoretical risk for transfusiontransmitted

Creutzfeldt-Jakob disease (CJD).

A 38-year-old female weighing 153 lb, who received

the rubella vaccine 2 months previously, presents to

donate whole blood. She also received 2 units of

packed cells after the delivery of her eighth child

8 weeks ago. Based on this information, would you

accept, permanently defer (PD), or temporarily defer

(TD) the donor?

a. Accept the donor

b. TD because of the packed cells 8 weeks ago

c. PD because of receiving blood products

d. TD because of the rubella vaccine

b. TD because of the packed cells 8 weeks ago

Receipt of the rubella vaccine results in a

temporary deferral of 4 weeks. Because this vaccine

was administered 2 months ago in this individual,

this would not cause a deferral.

Transfusion of blood, components, human tissue,

and/or plasma-derived clotting factor concentrates

results in a temporary deferral of

12 months, so this individual would be temporarily

deferred for 10 months based on the time of

transfusion.

A22-year-old female witha cousinwithAIDSwhohad

taken aspirin the day before and with needle marks on

both arms presents to donate whole blood. Based on

this information,would you accept, permanently defer

(PD), or temporarily defer (TD) the donor?

a. PD, needle marks on both arms

b. TD, needle marks on both arms

c. PD, cousin with AIDS

d. TD, because of the aspirin

a. PD, needle marks on both arms

Use of a needle to administer nonprescription

drugs is a condition for indefinite or permanent

deferral. Casual contact with a person with an

infectious disease generally is not a reason for

deferral. Potential donors who have ingested aspirin

are deferred (48 hours) only if they are donating

apheresis platelets.

Each unit of blood must be tested for all of the following

except:

a. Anti-HIV 1/2

b. HBsAg

c. Anti-HCV

d. Antigen to HCV

d. Antigen to HCV

Required tests for infectious disease screening

include:

• HBsAg

• Anti-HCV

• Anti-HBc

• HCV NAT

• Anti-HIV-1/2

• HIV NAT

• Anti-HTLV-I/II

• Syphilis - RPR or hemagglutination

• West Nile Virus (WNV) NAT

• IgG antibody to Trypanosoma cruzi (Chagas

disease)

The principle of the HBsAg test is to detect which of

the following?

a. Antigen in patient's plasma

b. Antigen on the patient's RBCs

c. Antibody in patient's serum

d. Antigen and antibody in patient's serum

a. Antigen in patient's plasma

The HBsAg test detects the surface antigen of the

hepatitis B virus in the blood. In an infected person,

this antigen can be detected before the antibody

to the core antigen (anti-HBc) is produced.

Cryoprecipitate is prepared by first thawing:

a. Fresh frozen plasma at 1 to 6 C, and then doing

a cold centrifugation to pack the cryoprecipitate

to the bottom so the plasma may be removed

b. Fresh frozen plasma at room temperature, then

placing in the freezer for 2 hours, then centrifuging

and removing the cryoprecipitate

c. Cryoprecipitate at 1 to 6 C, then pooling the

thawed cryoprecipitate in batches of 10 units,

then quickly refreezing

d. Cryoprecipitate at room temperature, then centrifugation

in the cold to concentrate the cryoprecipitate

to the bottom before adding more plasma

to reconstitute

a. Fresh frozen plasma at 1 to 6 C, and then doing a cold centrifugation to pack the cryoprecipitate to the bottom so the plasma may be removed

Cryoprecipitate (CRYO) is defined as the coldinsoluable

portion of FFP thawed at 1-6 C and

is suspended in 10-15 mL of plasma.

Platelets must be kept in constant motion for which

of the following reasons?

a. Maintain the pH so the platelets will be alive

before transfusion

b. Keep the platelets in suspension and prevent

clumping of the platelets

c. Mimic what is going on in the blood vessels

d. Preserve the coagulation factors and platelet

viability

a. Maintain the pH so the platelets will be alive before transfusion

Platelets must be gently agitated during storage by

the use of a rotator to prevent the pH from

decreasing below 6.2.

After thawing and pooling cryoprecipitate for transfusion

to a patient, the product should be stored at:

a. Room temperature

b. 1 to 6 C

c. 37 C

d. 0 C

a. Room temperature

Thawed cryoprecipitate components are stored at

room temperature after thawing.

Fresh frozen plasma must be thawed at which

temperature?

a. 1 to 6 C

b. Room temperature

c. 37 C

d. 40 C or higher

c. 37 C

FFP is thawed at temperatures of 30 C to 37 Cor

in an FDA-approved device.

Frozen red blood cells are prepared for transfusion

by thawing at:

a. Room temperature and then washing with saline

b. 37 C in a water bath and then washing with different

concentrations of saline

c. 37 C control incubator and then mixing well

before transfusion

d. 1 to 6 C for 2 days and then washing with different

concentrations of dextrose

b. 37 C in a water bath and then washing with different concentrations of saline

Frozen red blood cells are prepared for transfusion

by first thawing the unit at 37 C. Next,

the glycerol cyropreservative must be removed

through a stepwise decreasing osmolar solution

of saline.

Which is the most likely reason frozen deglycerolized

red blood cells would be used?

a. A patient with antibodies to a high-frequency

antigen

b. Pregnant women requiring intrauterine

transfusions

c. Emergency transfusion situations

d. Group AB Rh-negative patients

a. A patient with antibodies to a high frequency antigen

As frozen units need to be thawed and deglycerolized

prior to transfusion, use of frozen units in an

emergency transfusion situation is not practical.

Group AB Rh-negative patients can receive O, A,

B, or AB Rh-negative units, so transfusion needs

could likely be handled from available refrigerated

units of blood. There are special considerations that

must be made for pregnant women who requiring

an intrauterine transfusion, but a frozen unit of

red cells would likely only be used in the event of

an antibody to a high frequency antigen. Therefore

the best answer for this question is A. Red cell units

are usually frozen for long-term preservation to

maintain an inventory of rare units.

One indication for transfusion of thawed/pooled

cryoprecipitate would be replacement of which of

the following?

a. Factor X in hemophiliacs

b. Factor VIII in massively transfused patients

c. Fibrinogen

d. Volume

c. Fibrinogen

Indications for transfusion of cryoprecipitate

include von Willebrand's disease, Hemophilia A,

to control bleeding associated with fibrinogen

deficiency, and Factor XIII deficiency.

A contraindication for transfusing red blood cells to

a patient is if the patient:

a. Is massively bleeding

b. Has well-compensated anemia

c. Has bone marrow failure

d. Has decreased red blood cell survival

b. Has well-compensated anemia

Indications for transfusionof redbloodcells include

treatment of anemia in normovolemic patients and

physician decision based on the clinical status of the

patient. Patients that are massively bleeding, have

bone marrow failure, or have decreased red blood

cell survival have clinical situations thatwouldwarrant

transfusionbecauseof the needfor hemoglobin

replacement. In patients with compensated anemia,

the body has adapted to allow for adequate tissue

oxygenation. Transfusion should be withheld in

this case until the patient shows clinical signs of

inadequate tissue oxygenation.

Concerning the component and the required quality

control results, which of the following is a true

statement?

a. FFP must have 80 international units of fibrinogen

in 7 units tested

b. Cryoprecipitate must have 80 international units

of factor VIII

c. Leukocyte-reduced red blood cells must have

fewer than 3.31011 WBCs in each unit

d. Platelets must have no red blood cells

b. Cryoprecipitate must have 80 international units of factor VIII

FFP has no quality control or minimum requirements.

Cryo must have80 IU of Factor VIII

and150 mg of fibrinogen. Leukocyte reduced

red cells must have <5106 residual leukocytes

and 85% of original red cells retained. There

are no quality control or minimum requirements

for the number of red cells in platelets.

Fresh frozen plasma must be stored at:

a. Colder than 18 C for no longer than 1 year

from donation

b. Colder than 38 C for no longer than 1 year

from donation

c. Exactly 18 C for no longer than 1 year from

donation

d. 18 C to 38 C for up to 10 years from

donation

a. Colder than 18 C for no longer than 1 year from donation

FFP is stored at -18 C for 12 months,

or -65 C for 7 years with FDA approval.

The storage temperature for packed red blood cells is

_______________.

a. 1 to 10 C

b. 1 to 4 C

c. 1 to 6 C

d. 20 to 25 F

c. 1 to 6 C

Per AABB guidelines, packed red cells are stored

at 1 C to 6 C.

Platelets made from a single whole blood donation

should contain which of the following?

a. 3x1011 platelets in 90% of samples

b. 3.3x109 platelets in 75% of samples

c. 5.5x1010 platelets in 90% of samples

d. 10x1010 platelets in 75% of samples

c. 5.5X1010 platelets in 90% of samples

Platelets made from a single whole blood donation

(random platelets) should contain 5.5x10^10

platelets in 75% of the units tested.

Frozen red blood cells must be stored at

__________________.

a. 180 C or less

b. 18 C or less

c. 32 C or less

d. 65 C or less

d. 65 C or less

RBCs Frozen with 40% glycerol are stored

at -65 C for 10 years.

The temperature for incubation of the indirect antiglobulin

test (IAT) should be ____________.

a. 24 C

b. 6 C

c. 37 C

d. 37 +/- 10 C

c. 37 C

In the IAT, incubation takes place at 37 C for

a specified amount of time to allow antigenantibody

reactions to occur.

The temperature of a blood refrigerator without a

continuous recording device should be recorded:

a. Daily

b. Every 4 hours

c. Once every 24 hours

d. Every 30 minutes

b. Every 4 hours

Per AABB Standards, if an automated temperature

recording device is not used, then temperatures

of the blood component storage

environment must be measured manually every

4 hours.

When should quality control be performed on routine

blood typing reagents?

a. At the beginning of each shift

b. Once daily

c. Weekly

d. Only when opening a new vial

b. Once daily

As suggested by AABB, red cell reagents, antisera,

and antiglobulin serum should have quality

control performed each day of use.