Blood Bank Concepts
Which of the following set of conditions would NOT allow HDN to occur as a result of
Rh incompatibility: - ANSWER Mother Rh-negative, father Rh-negative
What is the purpose of a major crossmatch? - ANSWER Verify donor ABO packed-
cell compatibility
The use of cells with known blood groups to confirm ABO typing is known as: -
ANSWER Reverse grouping
Fresh frozen plasma : - ANSWER Should be transfused within 24 hours of thawing
What is the proper storage temperature for thawed Cryoprecipitate? - ANSWER 20
- 24 ºC.
Most antibodies present in cord blood are of ________ origin. - ANSWER maternal
What are the possible ABO genotypes of offspring from parents whose genotypes
are OO and AB: - ANSWER OA
OB
An aliquot of AS-1 red blood cells is being prepared from an intact packed cell unit
using a sterile connection device.
During the process of preparing an aliquot, the sterile device fails and blood drips
onto the counter from the product tubing. What should be done with the primary unit?
- ANSWER Change the expiration date to 24 hours
Kernicterus due to high levels of unconjugated bilirubin can cause brain damage in
newborns suffering from severe HDFN. - ANSWER True
The parents' blood types were AB and O. The blood group of any of their children
could ONLY be: - ANSWER Group A or B only
For the test results shown above, which of the following antibodies is most likely to
be causing the newborn's positive DAT? - ANSWER anti-K
The correct answer is anti-K.
Both the mother and infant are group A, eliminating ABO HDFN.
We are given the cell ID information for each of the screening cells. Screen cell 1 is
R1R1. Therefore these antigens are present: D,C, e.
Screen cell 2 is R2R2. Therefore these antigens are present: D,E,c
Screen cell 3 is rr. Therefore these antigens are present: c,e
The only cell that reacted was Screen cell 3. Both c and e are also present on the
nonreactive cells. The only choice that has not been eliminated is anti-K.
Also, the antibody screen reaction pattern (only cell 3 positive) is typical of anti-K.
An urticarial transfusion reaction is characterized by: - ANSWER Rash and hives
,Which one of the following is NOT a cause for donor deferral? - ANSWER Weighs
115 pounds
Why do so few patients transfused with un-crossmatched red cells in an emergency
experience a hemolytic transfusion reaction? Select the one best reason. - ANSWER
The incidence of unexpected red cell antibodies is relatively low.
What is the first step a transfusionist should take when a transfusion reaction is
suspected? - ANSWER Stop the transfusion, but keep the intravenous line open
with saline.
What is the fundamental purpose of the full, pre-transfusion crossmatch? - ANSWER
Detect antibodies in recipient serum/plasma that react with donor red cells.
At what phase of antibody screen testing is it most important to read the reactions in
order to detect clinically significant antibodies? - ANSWER AHG
Which of these methods is the MOST accurate and reliable for determining the
volume of fetal whole blood or red blood cells in the maternal circulation in order to
evaluate fetomaternal hemorrhage? - ANSWER Flow cytometry
What is the first line treatment for moderate to severe hemophilia A? - ANSWER
Lyophilized Factor VIII concentrate
For infants born to Rh negative females, a test for weak D is optional when initial D
typing shows the newborn to be Rh negative. - ANSWER False
The statement is false. For such infants, blood safety standards require a weak D
test to be performed when initial D typing shows the newborn to be Rh negative.
For transfusion services in the United States, which of the following incidents must
be reported to the Food and Drug Administration (FDA) because of a biological
product deviation? - ANSWER Incident C: The wrong specimen was used to
crossmatch a unit and the unit was issued.
To detect the presence of blocking antibodies fixed on the red cells of a newborn
infant: - ANSWER Use the direct antiglobulin test
When given during pregnancy, RhIg may cross the placenta and sensitize fetal D-
positive RBCs. - ANSWER True
Because RhIg contains IgG anti-D, it can cross the placenta and sensitize fetal Rh
positive red cells. Affected infants may be born with a weakly positive DAT, but
significant hemolysis does not occur.
Which one of these Lewis blood group system phenotypes usually produces anti-
Lea? - ANSWER Le(a--b-)
This antibody is found in the serum of Le(a-b-) secretors.
Which organism is MOST likely responsible for septic reactions associated with Red
Blood Cell transfusions? - ANSWER Yersina entercolitica
,A febrile nonhemolytic transfusion reaction is characterized by which of the
following? - ANSWER An increase in temperature of >1 degree C above 37
degrees during transfusion
Which type of blood component is most implicated in bacterial contamination? -
ANSWER platelets
IgM antibodies produced against red blood cells generally: - ANSWER React best
at room temperature
The hh genotype gives rise to: - ANSWER Bombay phenotype
Which of the following antigen groups is closely related to the ABO antigens on the
red cell membrane? - ANSWER I, i
Today, amniocentesis is preferred to Doppler sonography for monitoring the severity
of hemolytic disease of the fetus and newborn (HDFN). - ANSWER False
Because Doppler sonography is noninvasive, it is a safer alternative to
amniocentesis for fetal monitoring and has largely replaced serial amniocentesis for
predicting severity of HDFN.
If an Rh negative patient is administered a unit of R1R1 packed red cells, which one
of the following antibodies would be most likely to develop: - ANSWER Anti-D
R1R1 (DCe/DCe) cells are positive for the D antigen, which is the most immunogenic
antigen of the Rh system, followed by c and E.
Which symptom of HDFN does phototherapy help prevent? - ANSWER Kernicterus
Which of the following statements about high-frequency antigens is correct? -
ANSWER High-frequency antigens are common, but it's difficult to identify their
corresponding antibodies
The cause of the most severe life-threatening hemolytic transfusion reactions is: -
ANSWER Anti-A, Anti-B, Anti-A, B
If the mother is a Rh immune globulin (RhIg) candidate, blood safety standards
mandate that a test for weak D is compulsory when initial D typing shows a newborn
to be Rh negative. - ANSWER True
Weak D red cells can stimulate production of anti-D. Therefore, infants born to
mothers who are RhIg candidates must be tested for weak D.
RhIg is given to Rh negative women who deliver infants who are Rh positive or weak
D.
All of the following cellular antigens are important to an immunohematologist except:
- ANSWER Haptens
A hapten is an incomplete antigen.
, Which one of the following blood groups usually reacts LEAST strongly with anti-H? -
ANSWER A1
Of the blood groups that are listed, A1 has the least amount of H antigen and
therefore would react least strongly with anti-H.
Unexpected positive reactions encountered during forward ABO typing may be due
to: - ANSWER Acquired B antigen due to intestinal cancer
Based on the phenotype of the RBC screening cells, and patient results shown on
the right, which of the following antibodies CANNOT be ruled out? - ANSWER Anti-
C
Anti-Fya
A 300 µg dose of RhIg can suppress immunization to how many mL of D-positive
whole blood? - ANSWER 30 mL
One vial of 300µg RhIg can suppress immunization to a fetomaternal hemorrhage of
approximately 30 mL of D+ whole blood
At what frequency should quality control testing be performed on each lot of anti-
human globulin to be in compliance with the FDA's current good manufacturing
practices requirements? - ANSWER B. Each day of use
For which of the following antibodies is the DAT most likely to be negative when
testing a newborn for possible HDFN? - ANSWER anti-A
The DAT is most likely to be negative in ABO HDFN. It's possible that the washing
done as part of the DAT may break the bonds between anti-A (or anti-B) and the
newborn's poorly developed A (or B) antigens.
What is the MAXIMUM interval during which a recipient sample may be used for
crossmatching if the patient has recently been transfused or was pregnant within the
past 3 months? - ANSWER 3 days
Which of the following is the MOST likely discrepancy seen when a person
demonstrates an "acquired B-like" phenomenon? - ANSWER Forward typing
appears to be AB, but reverse groups like A
What should be the first step performed to resolve a case where all forward and
reverse ABO typing results are negative on a patient? - ANSWER Incubate all
testing tubes at 22ºc
Which of the following steps should be taken in the IMMEDIATE investigation of a
potential hemolytic transfusion reaction? (choose all that apply) - ANSWER ABO
and DAT on the post-transfusion patient sample
Check for a clerical error
Visual examination of the post-reaction and pre-reaction (if available) plasma for
hemolysis
Essential components of compatibility testing include all of the following except : -
ANSWER Direct Antiglobulin Test (DAT)
Which of the following set of conditions would NOT allow HDN to occur as a result of
Rh incompatibility: - ANSWER Mother Rh-negative, father Rh-negative
What is the purpose of a major crossmatch? - ANSWER Verify donor ABO packed-
cell compatibility
The use of cells with known blood groups to confirm ABO typing is known as: -
ANSWER Reverse grouping
Fresh frozen plasma : - ANSWER Should be transfused within 24 hours of thawing
What is the proper storage temperature for thawed Cryoprecipitate? - ANSWER 20
- 24 ºC.
Most antibodies present in cord blood are of ________ origin. - ANSWER maternal
What are the possible ABO genotypes of offspring from parents whose genotypes
are OO and AB: - ANSWER OA
OB
An aliquot of AS-1 red blood cells is being prepared from an intact packed cell unit
using a sterile connection device.
During the process of preparing an aliquot, the sterile device fails and blood drips
onto the counter from the product tubing. What should be done with the primary unit?
- ANSWER Change the expiration date to 24 hours
Kernicterus due to high levels of unconjugated bilirubin can cause brain damage in
newborns suffering from severe HDFN. - ANSWER True
The parents' blood types were AB and O. The blood group of any of their children
could ONLY be: - ANSWER Group A or B only
For the test results shown above, which of the following antibodies is most likely to
be causing the newborn's positive DAT? - ANSWER anti-K
The correct answer is anti-K.
Both the mother and infant are group A, eliminating ABO HDFN.
We are given the cell ID information for each of the screening cells. Screen cell 1 is
R1R1. Therefore these antigens are present: D,C, e.
Screen cell 2 is R2R2. Therefore these antigens are present: D,E,c
Screen cell 3 is rr. Therefore these antigens are present: c,e
The only cell that reacted was Screen cell 3. Both c and e are also present on the
nonreactive cells. The only choice that has not been eliminated is anti-K.
Also, the antibody screen reaction pattern (only cell 3 positive) is typical of anti-K.
An urticarial transfusion reaction is characterized by: - ANSWER Rash and hives
,Which one of the following is NOT a cause for donor deferral? - ANSWER Weighs
115 pounds
Why do so few patients transfused with un-crossmatched red cells in an emergency
experience a hemolytic transfusion reaction? Select the one best reason. - ANSWER
The incidence of unexpected red cell antibodies is relatively low.
What is the first step a transfusionist should take when a transfusion reaction is
suspected? - ANSWER Stop the transfusion, but keep the intravenous line open
with saline.
What is the fundamental purpose of the full, pre-transfusion crossmatch? - ANSWER
Detect antibodies in recipient serum/plasma that react with donor red cells.
At what phase of antibody screen testing is it most important to read the reactions in
order to detect clinically significant antibodies? - ANSWER AHG
Which of these methods is the MOST accurate and reliable for determining the
volume of fetal whole blood or red blood cells in the maternal circulation in order to
evaluate fetomaternal hemorrhage? - ANSWER Flow cytometry
What is the first line treatment for moderate to severe hemophilia A? - ANSWER
Lyophilized Factor VIII concentrate
For infants born to Rh negative females, a test for weak D is optional when initial D
typing shows the newborn to be Rh negative. - ANSWER False
The statement is false. For such infants, blood safety standards require a weak D
test to be performed when initial D typing shows the newborn to be Rh negative.
For transfusion services in the United States, which of the following incidents must
be reported to the Food and Drug Administration (FDA) because of a biological
product deviation? - ANSWER Incident C: The wrong specimen was used to
crossmatch a unit and the unit was issued.
To detect the presence of blocking antibodies fixed on the red cells of a newborn
infant: - ANSWER Use the direct antiglobulin test
When given during pregnancy, RhIg may cross the placenta and sensitize fetal D-
positive RBCs. - ANSWER True
Because RhIg contains IgG anti-D, it can cross the placenta and sensitize fetal Rh
positive red cells. Affected infants may be born with a weakly positive DAT, but
significant hemolysis does not occur.
Which one of these Lewis blood group system phenotypes usually produces anti-
Lea? - ANSWER Le(a--b-)
This antibody is found in the serum of Le(a-b-) secretors.
Which organism is MOST likely responsible for septic reactions associated with Red
Blood Cell transfusions? - ANSWER Yersina entercolitica
,A febrile nonhemolytic transfusion reaction is characterized by which of the
following? - ANSWER An increase in temperature of >1 degree C above 37
degrees during transfusion
Which type of blood component is most implicated in bacterial contamination? -
ANSWER platelets
IgM antibodies produced against red blood cells generally: - ANSWER React best
at room temperature
The hh genotype gives rise to: - ANSWER Bombay phenotype
Which of the following antigen groups is closely related to the ABO antigens on the
red cell membrane? - ANSWER I, i
Today, amniocentesis is preferred to Doppler sonography for monitoring the severity
of hemolytic disease of the fetus and newborn (HDFN). - ANSWER False
Because Doppler sonography is noninvasive, it is a safer alternative to
amniocentesis for fetal monitoring and has largely replaced serial amniocentesis for
predicting severity of HDFN.
If an Rh negative patient is administered a unit of R1R1 packed red cells, which one
of the following antibodies would be most likely to develop: - ANSWER Anti-D
R1R1 (DCe/DCe) cells are positive for the D antigen, which is the most immunogenic
antigen of the Rh system, followed by c and E.
Which symptom of HDFN does phototherapy help prevent? - ANSWER Kernicterus
Which of the following statements about high-frequency antigens is correct? -
ANSWER High-frequency antigens are common, but it's difficult to identify their
corresponding antibodies
The cause of the most severe life-threatening hemolytic transfusion reactions is: -
ANSWER Anti-A, Anti-B, Anti-A, B
If the mother is a Rh immune globulin (RhIg) candidate, blood safety standards
mandate that a test for weak D is compulsory when initial D typing shows a newborn
to be Rh negative. - ANSWER True
Weak D red cells can stimulate production of anti-D. Therefore, infants born to
mothers who are RhIg candidates must be tested for weak D.
RhIg is given to Rh negative women who deliver infants who are Rh positive or weak
D.
All of the following cellular antigens are important to an immunohematologist except:
- ANSWER Haptens
A hapten is an incomplete antigen.
, Which one of the following blood groups usually reacts LEAST strongly with anti-H? -
ANSWER A1
Of the blood groups that are listed, A1 has the least amount of H antigen and
therefore would react least strongly with anti-H.
Unexpected positive reactions encountered during forward ABO typing may be due
to: - ANSWER Acquired B antigen due to intestinal cancer
Based on the phenotype of the RBC screening cells, and patient results shown on
the right, which of the following antibodies CANNOT be ruled out? - ANSWER Anti-
C
Anti-Fya
A 300 µg dose of RhIg can suppress immunization to how many mL of D-positive
whole blood? - ANSWER 30 mL
One vial of 300µg RhIg can suppress immunization to a fetomaternal hemorrhage of
approximately 30 mL of D+ whole blood
At what frequency should quality control testing be performed on each lot of anti-
human globulin to be in compliance with the FDA's current good manufacturing
practices requirements? - ANSWER B. Each day of use
For which of the following antibodies is the DAT most likely to be negative when
testing a newborn for possible HDFN? - ANSWER anti-A
The DAT is most likely to be negative in ABO HDFN. It's possible that the washing
done as part of the DAT may break the bonds between anti-A (or anti-B) and the
newborn's poorly developed A (or B) antigens.
What is the MAXIMUM interval during which a recipient sample may be used for
crossmatching if the patient has recently been transfused or was pregnant within the
past 3 months? - ANSWER 3 days
Which of the following is the MOST likely discrepancy seen when a person
demonstrates an "acquired B-like" phenomenon? - ANSWER Forward typing
appears to be AB, but reverse groups like A
What should be the first step performed to resolve a case where all forward and
reverse ABO typing results are negative on a patient? - ANSWER Incubate all
testing tubes at 22ºc
Which of the following steps should be taken in the IMMEDIATE investigation of a
potential hemolytic transfusion reaction? (choose all that apply) - ANSWER ABO
and DAT on the post-transfusion patient sample
Check for a clerical error
Visual examination of the post-reaction and pre-reaction (if available) plasma for
hemolysis
Essential components of compatibility testing include all of the following except : -
ANSWER Direct Antiglobulin Test (DAT)
