Assessment BB Flashcards
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
b. Phenotyping
Phenotyping, or the physical expression of a genotype, is the type of testing routinely performed in the blood bank. An individual, for example, may have the AO genotype but phenotypes as group A.
Which genotype(s) will give rise to the Bombay phenotype?
a. HH only
b. HH and Hh
c. Hh and hh
d. hh only
d. hh only
The Bombay phenotype will be expressed only when no H substance is present. The Oh type is expressed by the genotype hh. Bombays produce naturally occurring anti-H, and their serum agglutinates group O red cells in addition to red cells from groups A, B, and AB persons.
Which of the following describes the expression of most blood group antigens?
a. Dominant
b. Recessive
c. Codominant
d. Corecessive
c. Codominant
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 red cells.
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
d. All are possible
A mating between AO and BO persons can result in an offspring with a blood type of A, B, AB, or O.
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
d. The patient may have developed alloantibodies
c. The patient may be a Bombay
What antibodies are formed by a Bombay individual?
a. Anti-A and anti-B
b. Anti-H
c. Anti-AB
d. Anti-A, anti-B and anti-H
d. Anti-A, anti-B and anti-H
A Bombay individual does not express A, B, or H antigens; therefore anti-A, B, and H are formed. Because a Bombay individual has three antibodies, the only compatible blood must be from another Bombay donor.
Acquired B antigens have been found in:
a. Bombay individuals
b. Group O persons
c. All blood groups
d. Group A persons
d. Group A persons
The acquired B phenomenon is only seen in group A persons.
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
c. Anti-A 4+, anti-B 1+, A1 cells neg, B cells 4+
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, the reverse grouping is the same for a group A person.
Which blood group has the LEAST amount of H antigen?
a. A1B
b. A2
c. B
d. A1
e. O
a. A1B
The A1B blood group has the least amount of H antigen. This is due to both A and B epitopes present on red cells compromising the availability of H epitopes. A1B cells will yield weak reactions with anti-H lectin.
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
b. Incubate at 22°C or 4°C to enhance weak expression
All negative results may be due to weakened antigens or antibodies. Room temperature or lower incubation temperature may enhance expression of weakened antigens or antibodies.
N-acetyl-D-galactosamine is the immunodominant carbohydrate that reacts with:
Arachis hypogaea
Salvia sclarea
Dolichos biflorus
Ulex europaeus
Dolichos biflorus
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.
A stem cell transplant patient 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
c. Immunodeficiency
WEAK OR MISSING ANTIBODIES
A transplant patient 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.
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
b. Rh negative
Rh positive refers to the presence of D antigen; Rh negative refers to the absence of the D antigen. These designations are for D antigen only and do not involve other Rh antigens.
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 due to a disease state
d. A D mosaic may make antibodies to missing antigen parts
d. A D mosaic may make antibodies to missing antigen parts
The D antigen is comprised of 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.
What does the genotype —/— represent in the Rh system?
a. Rh negative
b. D mosaic
c. Rh null
d. Total Rh
c. Rh null
A person who is Rh null shows no Rh antigens on his or her RBCs.
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 + indirect antiglobulin test
d. 37°C incubation + indirect antiglobulin test
Weak D testing requires both 37°C incubation and the IAT procedure.
Which of the following sugars must be present on a precursor substance for A and B antigenic activity to be expressed?
a. D-Galactose
b. N-Acetylgalactosamine
c. Glucose
d. L-Fucose
d. L-Fucose
Without H substance present, the sugars giving A or B antigenic activity cannot attach.
Lectins are useful in determining the cause of abnormal reactions in blood bank serology. These lectins are frequently labeled as anti-H, anti-A1 etc. The nature of these lectins is explained by which of the following?
a. An early form of monoclonal antibody produced in nonvertebrates
b. A plant substance that chemically reacts with certain RBC antigens
c. Naturally occurring antibodies in certain plants
d. The ability of plants to respond to RBC antigens by antibody production
b. A plant substance that chemically reacts with certain RBC antigens
Lectins are proteins present in plants, often derived from the seeds of plants.
If a patient has the Rh genotype DCe/DCe and receives a unit of red blood cells from a DCe/dce individual, what Rh antibody might the patient develop?
a. Anti-C
b. Anti-c
c. Anti-d
d. Anti-E
b. Anti-c
The unit from the DCe/dce donor has the c antigen that the patient lacks.
Which of the blood group systems is associated with antibodies that are generally IgM?
a. Rh
b. Duffy
c. Kell
d. Lewis
d. Lewis
Lewis system antibodies are generally IgM.
In which of the following blood group systems may the red blood cell typing change during pregnancy?
a. P
b. MNS
c. Lewis
d. Duffy
c. Lewis
The Lewis typings of a pregnant woman may appear to be Le(a-b-), even though the original typing may have been Le(a-b+).
All are associated with Group I ABO discrepancies, except:
a. Newborns and elderly patients
b. Patients with congenital immunodeficiency diseases
c. Patients using immunosuppressive drugs
d. Subgroups of A or B
d. Subgroups of A or B
An antigen present on most D-positive and all C-positive RBCs:
a. G
b. f
c. rhi
d. Cw
a. G
From the following ABO mating, what are the probabilities of the ABO PHENOTYPES of potential offspring? Mother: Group O; Father: Group B (heterozygous).
a. 50% BO, 50% OO
b. 100% BO
c. 50% B, 50% O
d. 50% B, 50% A
c. 50% B, 50% O
Rh antibodies are predominantly:
a. IgM
b. IgG
c. IgD
d. IgA
b. IgG
Rh immune globulin provides ____ protection against fetal D antigen.
a. Active
b. Passive
c. Antigen-stimulated
d. Antibody-stimulated
b. Passive
If an Rh negative woman recently delivered an Rh positive baby and the Kleihauer-Betke test result is 5%, how many vials of Rh Ig should be administered?
a. 6
b. 7
c. 8
d. 9
d. 9
The glass surface of an Rh viewbox should be _____ C.
a. Between 45 and 50C
b. Between 26 and 39C
c. Between 16 and 25C
d. Between 0 and 15C
a. Between 45 and 50C
Anti-c can be formed by persons with the genotype:
a. R1R2
b. R1R1
c. R2r
d. rr
b. R1R1
The results of a Kleihauer-Betke stain indicate a feto-maternal hemorrhage of 35 mL of whole blood. How many vials of Rh immune globulin would be required?
a. 1
b. 2
c. 3
d. 4
b. 2
ABH substances would be found in the saliva of a group B secretor:
a. H
b. A and H
c. B and H
d. A, B and H
c. B and H
The immunogenicity of the common Rh antigens may be described from greatest to least:
a. D>C>E>c>e
b. D>c>E>e>C
c. c>D>C>E>e
d. D>c>E>C>e
d. D>c>E>C>e
An individual with genes A, H, Se and lele has which of the following phenotypes?
a. ABH, Le (a-b-)
b. ABH, Le (a+b-)
c. AH, Le (a-b-)
d. AH, Le (a+b-)
c. AH, Le (a-b-)
The antigen system closely associated phenotypically with Rh is known as:
a. McCoy
b. Lutheran
c. Duffy
d. LW
d. LW
“O” secretor person would demonstrate what substance/s in his saliva:
a. A
b. B
c. H
d. A and B
c. H
Which of the following is NOT true about the anti-A and anti-B?
a. They are well-developed at birth
b. They are “naturally occurring”
c. They are IgM isoagglutinins
d. They are reactive at cold temperature
a. They are well-developed at birth
What chain is formed when the terminal galactose on the ABH precursor substance is attached to the N-acetylglucosamine in beta 1, 4 linkage?
a. Type 1 precursor chain
b. Type 2 precursor chain
b. Type 2 precursor chain
Type 1 precursor substance
Beta 1 → 3 linkage between galactose and N-acetylglucosamine
Type 2 precursor substance
Beta 1 → 4 linkage between galactose and N-acetylglucosamine
Rh-HDN occurs in what type of mother and child:
a. Mother and child are both Rh (-)
b. Mother and child are both Rh (+)
c. Mother is Rh (+), child is Rh (-)
d. Mother is Rh (-), child is Rh (+)
d. Mother is Rh (-), child is Rh (+)
ABO antibodies in infants are detected in serum:
a. At birth in cord blood
b. 2 to 4 weeks after birth
c. 1 to 2 months after birth
d. 3 to 6 months after birth
d. 3 to 6 months after birth
Which cells agglutinate most strongly with Ulex europaeus lectin?
a. O
b. A1
c. A1B
d. A2B
e. Oh (Bombay phenotype)
a. O
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 patient’s 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.
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. D- - / D - -
Individuals with the D - - phenotype may possess more D antigen because they have inherited a nonfunctioning RHCE gene.
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.
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
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.
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
Rh antibodies react best at what temperature (°C)?
a. 15
b. 18
c. 22
d. 37
d. 37
Which of the following is the most common haplotype in the ASIAN population?
a. DCe
b. DcE
c. Dce
d. ce
a. DCe
R1 (DCe) - Whites, Asians and Native Americans
R0 (Dce) - Blacks
If a patient who is R1R1 is transfused with RBCs that are Ror, which antibody is he most likely to produce?
a. Anti-D
b. Anti-c
c. Anti-e
d. Anti-G
b. Anti-c
Which of the following characteristics best describes Lewis antibodies?
a. IgM, naturally occurring, cause HDN
b. IgM, naturally occurring, do not cause HDN
c. IgG, in vitro hemolysis, cause hemolytic transfusion reactions
d. IgG, in vitro hemolysis, do not cause hemolytic transfusions
b. IgM, naturally occurring, do not cause HDN
Transformation to Leb phenotype after birth may be as follows:
a. Le(a–b–) to Le(a+b–) to Le(a+b+) to Le(a–b+)
b. Le(a+b–) to Le(a–b–) to Le(a–b+) to Le(a+b+)
c. Le(a–b+) to Le(a+b–) to Le(a+b+) to Le(a–b–)
d. Le(a+b+) to Le(a+b–) to Le(a–b–) to Le(a–b+)
a. Le(a–b–) to Le(a+b–) to Le(a+b+) to Le(a–b+)
In children who inherit both Le and Se genes, the transformation can be followed from the Le(a–b–) phenotype at birth to Le(a+b–) after 10 days to Le(a+ b+) and finally to Le(a–b+), the true Lewis phenotype, after about 6 years.
Transfusion-transmissible infectious agents for which UNIVERSAL SCREENING of all donations in all countries is recommended. Check four (4) boxes.
Cytomegalovirus (CMV)
Plasmodium sp. (malaria)
Human immunodeficiency virus (HIV)
Hepatitis B virus (HBV)
Hepatitis C virus (HCV)
Treponema pallidum (syphilis)
Human immunodeficiency virus (HIV)
Hepatitis B virus (HBV)
Hepatitis C virus (HCV)
Treponema pallidum (syphilis)
Transfusion-transmissible infectious agents for which universal screening of all donations in all countries is recommended:
Screening for the following four infections that are transmissible by transfusion is recommended as mandatory for the provision of a safe blood supply. These infections can cause chronic disease with possible serious consequences and present the greatest infection risk to recipients of transfusion:
1. Human immunodeficiency virus (HIV)
2. Hepatitis B virus (HBV)
3. Hepatitis C virus (HCV)
4. Treponema pallidum (syphilis)
What is the maximum volume of blood that can be collected from a 110-lb donor, including samples for processing?
450 mL
500 mL
525 mL
550 mL
525 mL
When RBCs are stored, there is a “shift to the left.” This means:
Hemoglobin-oxygen affinity increases, owing to an increase in 2,3 -DPG
Hemoglobin-oxygen affinity increases, owing to a decrease in 2,3-DPG
Hemoglobin-oxygen affinity decreases, owing to a decrease in 2,3-DPG
Hemoglobin-oxygen affinity decreases, owing to an increase in 2,3-DPG
Hemoglobin-oxygen affinity increases, owing to a decrease in 2,3-DPG
What are the current storage time and storage temperature for platelet concentrates and apheresis platelet components?
5 days at 1°C to 6°C
5 days at 24°C to 27°C
5 days at 20°C to 24°C
7 days at 22°C to 24°C
5 days at 20°C to 24°C
Prestorage pooled platelets can be stored for:
4 hours
24 hours
5 days
7 days
5 days
Because they are produced in a CLOSED SYSTEM, they can be stored for 5 days from collection.
Additive solutions are approved for storage of red blood cells for how many days?
21
42
35
7
42
One criterion used by the FDA for approval of new preservation solutions and storage containers is an average 24-hour post-transfusion RBC survival of more than:
50%
60%
65%
75%
75%
What is the lowest allowable pH for a platelet component at outdate?
6
5.9
6.8
6.2
6.2
Which of the following occurs during storage of red blood cells?
pH decreases
2,3-DPG increases
ATP increases
Plasma K+ decreases
pH decreases
Which of the following is approved for bacterial detection specific to extending the expiration of apheresed platelets to 7 days?
BacT/ALERT
eBDS
Gram stain
Pan Genera Detection (PGD) test
Pan Genera Detection (PGD) test
In November 2009, the FDA approved the first rapid test to detect bacteria in platelets—the Pan Genera Detection (PGD) test (Verax Biomedical).
The pattern of inheritance most commonly expressed by blood group genes is:
X-linked recessive
Autosomal recessive
Autosomal codominant
X-linked codominant
Autosomal codominant