Blood bank Unit 1 test

Equal expression of two different inherited genes as in most blood group systems

Codominant genes

Hemolysis was observed at room temperature when testing a patient's serum with reagent red cells used for screening. When this test was repeated using the patient's plasma, no hemolysis was observed. What was the most likely explanation for the different reactions?

Complement activation was inhibited by calcium in the plasma sample.

Which of the following clinical applications applies to molecular testing for blood group antigens?

Confirm the D type of blood donors, identify fetus at risk of HDFN, predict the phenotype of a patient with autoimmune hemolytic anemia (All of the above)

Accuracy

Degree to which a measurement represents the true value

Incubation step is not necessary

Direct antiglobulin test

tests for certain clinical conditions such as hemolytic disease of the newborn and autoimmune hemolytic anemia

Direct antiglobulin test

OSHA

Ensures safe and healthful working conditions

Validation

Establishing that a specific process produces an expected result

Competency assessment

Evaluation of an employee's ability to perform a specific skill

What portion of the antibody molecule binds to receptors on macrophages and assists in the removal of antibody bound to red cells?

Fc fragment

Which of the following organizations are involved in the regulation of blood banks?

Food and Drug Administration

Which of the following is true regarding good manufacturing processes?

GMPs are legal requirements established by the FDA

The linked HLA genes on each chromosome are inherited as a

Haplotype

When two genes are close together on the same chromosome and are inherited as a group or bundle

Haplotypes

Of the following markers used to test for paternity, which marker provides the most useful statistical value?

Human leukocyte antigen typing

Viable region of an immunoglobulin

Idiotype

Found in secretions such as breast milk

IgA

Associated with allergic reactions and mast cell activation

IgE

Able to cross the placenta

IgG

Has the highest serum concentration

IgG

What immunoglobulin class is capable of crossing the placenta?

IgG

What immunoglobulin class reacts best by antiglobulin testing?

IgG

Which immunoglobulin class is impacted by the zeta potential in a hemagglutination test?

IgG

Associated with immediate spin in vitro reactions

IgM

Associated with intravascular cell destruction

IgM

Efficient in activation of the complement cascade

IgM

Has the highest number of antigen binding sites

IgM

Select the immunoglobulin class produced first in the primary immune response

IgM

What immunoglobulin class reacts best at room temperature at immediate spin?

IgM

Why is polyethylene glycol reagent added to the screen or panel?

Increase the avidity of IgG antibodies

In order to enhance the reaction of an antibody in vitro, it may be necessary to adjust which of the following?

Increase the incubation time in the incubator

In a routine audit of a facilities blood collection area, the quality assurance department found that the blood bags used on that particular day had expired. What is the appropriate course of action?

Initiate a root cause analysis and quarantine the blood collected in the expired bags. Notify the FDA since the expired bags were distributed.

Root cause analysis

Investigation and identification of of the factors that contributed to an error

One of the two types of light chains

Kappa

CDC

Makes recommendations to OSHA regarding the prevention of disease transmissions

Preventive maintenance

Maximizes the duration of equipment and increases the reliability of the equipment

A laboratory technologist decided she would like to bring her lab coat home for laundering because it had too many wrinkles when it was returned by the laboratory's laundry service. Is this practice acceptable?

No, because the laboratory is a biosafety level 2, and lab coats may not be removed

A technologist in training noticed that the person training her had not recorded the results of a test. To be helpful, she carefully recorded the results she saw at a later time, using the technologist's initials. Is this an acceptable procedure?

No; she should have brought the error to the technologist's attention.

The children of a group AB mother and group B father could phenotype as all fo the following except

O

Reagent to identify the specificity of a red cell antibody

Panel cells

When testing for the A antigen in a patient, what would you use to perform the test?

Patient's red cells and anti-A

All of the following are responsibilities of the quality assurance department of a blood bank except

Performing quality control

What reagent contains antibodies to multiple antigenic epitopes?

Polyclonal-based

Technique used to replicate a specific DNA sequence

Polymerase chain reaction

Which red cells are used to screen for antibodies in donor samples?

Pooled screening cells

In the PCR reaction, what is the term for the short pieces of single stranded DNA that are complementary and mark the sequence to amplified?

Primers

Short segment of DNA with a known sequence that can be labeled with a marker

Probe

Calibration

Process of standardizing an instrument against a known value

AABB

Professional organization that accredits blood banks and transfusion services

CAP

Provides peer reviewed accreditation for hospital labs

Recall

Removal of products from the market that might compromise the safety of the recipient

The antiglobulin test was performed using tube technology. A button of cells was observed at the bottom of the microtube following centrifugation. How do you interpret the result?

Result is a negative reaction

Reagent to detect the presence of red cell antibodies

Screening cells

Which of the following terms provides evidence for reagent red cell deterioration?

Spontaneous agglutination, significant hemolysis, loss of agglutination strength over time (all of the above)

Change control

System to plan and implement changes to prevent problems

Quality control

Testing to determine the accuracy and precision of reagents and equipment

Proficiency test

The CAP survey is an example

Why is incubation omitted in the direct antihuman globulin test?

The antigen-antibody complex has already formed in vivo

Several units were released to a hospital by mistake before all viral marker testing was completed. What is the appropriate course of action?

The error is reportable, and the Food and Drug Administration must be contacted. Call the hospital and request a quarantine of the remaining products in inventory.

A facility does not validate a refrigerator before use. What is a potential outcome?

The facility is in violation of current good manufacturing practices and could be cited by the Food and Drug Administration.

When using the Hardy-Weinberg equation to calculate genetic frequencies, which of the following must be true?

The population statistics must be large. Mutations cannot occur. Mating must be random (All of the above)

Which of the following statements is true regarding high protein anti D reagents

They have been largely replaced with low protein monoclonal reagents. They contain approximately 20% bovine albumin. They may increase the possibility of a false-positive reaction, requiring the use of a control. (All of the above)

How would you interpret the results if both the anti D and Rh control were 2+ agglutination reactions?

Unable to determine without further testing

Which of the following is an example of an unacceptable record keeping procedure?

Using dittos in columns to save time

Rouleaux is a false-positive reaction that would not likely be observed during which of the following tests

Weak D test

A father carries the Xga blood group trait and passes it on to all of his daughters but to none of his sons. What type of inheritance pattern does this demonstrate?

X-linked dominant

In the solid phase red cell adherence test, how does a negative test appear?

a button of cells on the bottom of the well

Employee training takes place

after hiring and following implementation of new procedures

Personal protective equipment includes:

all of the above

Which of the following is not an advantage of using a monoclonal antibody over a polyclonal antibody?

all variations of the antigen can be detected

Amplified target sequences of DNA produced by polymerase chain reaction

amplicon

What specificities does polyspecific antihuman globulin contain?

anti-IgG and anti-C3d

Which of the following is responsible for the activation of the classic pathway of complement?

antibody bound to antigen

In a serologic test, the term prozone is also known as:

antibody excess

Select the test that uses IgG-sensitized red cells (check cells).

antiglobulin test

An antigen that originates from the individual is termed

autologous

How are most blood group systems inherited?

autosomal codominant

Detects IgG or complement-coated red cells

both the direct and indirect antiglobulin test

Requires washing the cells several times before the addition of antihuman globulin reagent

both the direct and indirect antiglobulin test

What is the purpose of adding antibody sensitized red cells following the antiglobulin test?

check that the wash procedure was sufficient to remove unbound antibodies

Select the portion of the antibody molecule that imparts the antibody's unique class function.

constant region of heavy chain

Plans that provide the framework for establishing quality assurance in an organization are:

continuous quality improvement plan.

Select the substance that regulates the activity of other cells by binding to specific receptors

cytokines

FDA

ensures safety and efficacy of biologics, drugs and devices

Part of the antigen that the immunoglobulin binds to

epitope

A technologist added 4 drops of a 5% red cell suspension instead of the required 1 drop to a hemagglutination test. What is the potential consequence to the test results?

false negative

What is the potential effect in a tube agglutination test if a red cell suspension with a concentration greater than 5% is used?

false negatives

Select the method that uses a dextran-acrylamide matrix.

gel technology

What part of the immunoglobulin molecule distinguishes the isotype?

heavy chain

The standard operating procedure is a document that

helps achieve consistency of results

A person whose red cells type as M+N+ with antisera would be

heterozygote

Imparts flexibility to the immunoglobulin molecule

hinge region

In safety training, employees must become familiar with all of the following except

how to perform cardiopulmonary resuscitation on a donor or other employee.

The binding of two complementary pairs of DNA

hybridization

Monoclonal antibodies are prepared

in vitro

The type of immunoglobulins determined by the heavy chain

isotype

All of the following are true regarding competency testing except

it is required only if the technologist has no experience.

Reagent derived from plants used to distinguish group A1 from group A2 red cells

lectins

The gel technology method uses a concentration of red cells that is:

lower than tube techniques

When does crossing over occur?

meiosis

When an individual is group A, which of the following genetic terms applies?

phenotype

Reagent antibodies prepared from human sources are:

polyclonal in specificity

Having two or more alleles at a given gene locus

polymorphic

In relationship testing, a direct exclusion is established when a genetic marker is

present in the child but absent in both the mother and alleged father.

Unacceptable quality control results for the antiglobulin test performed in test tubes may be noticed if:

preventive maintenance has not been performed on the cell washer, the technologist performing the test was never trained, the reagents used were improperly stored (All of the above)

Marks the sequence to be amplified during PCR

primer

Where are product limitations and technical considerations for each reagent located

product insert

What biological molecules are considered the most immunogenic?

proteins

When a gene product is expressed only when it is inherited by both parents

recessive

Which of the following will cause an antigen to elicit a greater immune response?

size greater than 10,000 daltons

Extravascular destruction of blood cells occurs in the

spleen

Audit

systematic evaluations to determine whether procedures are being followed

Blood irradiators require all of the following safety procedures except:

that the user have a degree in radiology

Biosafety levels determine:

the degree of risk for certain areas of a health care facility to exposure to infectious diseases.

Solid-phase red cell adherence used for antibody detection has an advantage over tube testing because:

the endpoint is more clearly defined

If two traits occur higher in a population together than each occurs separately, they may be linked. What does this fact suggest?

the genes are close together on the same chromosome

Which of the following statements is true regarding IgG sensitized red cells?

they must be used to confirm a negative antiglobulin tube test

Mitosis results in

two cells with the same number of chromosomes as the parent cell

Select the region of the antibody molecule responsible for imparting unique antibody specificity.

variable region

If anti-M was reacted with red cells that are M+N+, how would they compare with red cells that are M+N-?

weaker

How is RNA different from DNA?

1) has ribose not deoxyribose 2) contains Uracil (U) instead of Thymine 3) usually single stranded (All of the above)

What is the approximate probability of finding a compatible unit of blood for a D positive patient with antibodies for C, E and K if the frequency of C is 70%, E is 30% and K is 10%?

2 out of 10 units

Following centrifugation of the gel card, red cells are observed to be evenly dispersed throughout one of the microtubes. This reaction could be graded as a:

2+

What temp is used for incubation in the indirect antihuman globulin test?

37 Celsius

After adding antigen and antibody to a test tube, one large agglutinate was observed. How should this reaction be graded?

4+

In a random population 16% of the population is homozygous for a particular trait. What percentage of the same population is heterozygous for that particular trait?

48%

What is an advantage of Nucleic Acid Testing for viral marker testing?

A small amount of of DNA/RNA can be detected

What is the meaning of the term autosomal?

A trait that is not carried on the sex chromosomes

Reagent used in the identification of ABO antibodies

A1 and B cells

Reagent used to determine the ABO antigenic compositions of a patients red cells

ABO antisera

In a family study, all four siblings in the family had a different blood type: A, B, O, and AB. What is the most likely genotypes of the parents?

AO and BO

An antibody identified in the transfusion service appeared to be reacting stronger following the second exposure to an antigen from a transfusion. The most likely explanation of this observation is

Affinity maturation of the immunoglobulin molecule, anamnestic response and isotype switching (all of the above)

Select the term that describes cells or from a genetically different individual within the same species.

Allogenic

A gene that does not express a detectable product

Amorphic genes

Which of the following red cell antigens do proteolytic enzymes destroy?

Antigens Fya and Fyb in the Duffy system

Select the cell involved in humoral immunity.

B lymphocytes

At what point in the employment process should safety training take place?

Before independent work is permitted and annually thereafter

What process is described by opsonization?

Binding to cells or antigens

In the complement cascade, lysis of the target cell is mediated by which of the following components?

C5 to C9