Blood Bank Week 8 Game

Good to study for final blood bank exam
The Du test is performed by incubating a patient's red cells with:
anti-D serum following by washing and antihuman globulin (AHG) reagent
A direct antiglobulin test is performed using polyspecific antisera. The result is 3+ DAT using only anti-IgG is performed next. The result is negative which of the following substances is most likely causing the positive reaction
A donor is tested with Rh antisera, with the following results:
Anti-D +
anti-e +
Rh control 0
What is the probable Rh genotype
AABB requires that patients samples for compatibility testing be stored for at least:
7 days after transfusion
Most "naturally occurring" ABO system antibodies fall into which class
The immediate spin testing on a unit of donor blood with anti-D is negative. A weak D tst is performed on the unit of donor blood and exhibits a 2+ reaction. The donor blood unit is labeled as
D positive
Mixing patient serum and donor red cells together and observing for direct cell lysis or agglutination is known as
Major crossmatch
The d antigen is
A patient's antibody screen is positive with Cell #2 the autocontrol is negative, is the antibody responsible for the positive screen most likely an alloantibody or an autoantibody
An individual lacking all antigens of the Rh blood group system is classified as
Rh null
A mother is Rh-negative and the father Rh-positve their baby is Rh-negative It may be concluded that
The father is heterozygous Rh-positve
Forward: Anti-A 2+mf, anti-B: 0
Reverse: A1 cells: 0, B cells: 3+
What could be a plausible explanation for this discrepancy
group O blood products given to group A
Which ABO phenotype selection contains the most H antigen and the least H antigen, respectively on the red cell's surface
O (most), A1B (least)
ABH soluble antigens are determined by the presence of the :
Se gene
Using Wiener nomenclature, a patien is r' what Rh antigens does this patient possess
The terminal sugar responsible for the A antigen is
In the ABO system, the O gene is considered
Using Rosenfield terminology a patient has Dce/dCe how would this be written
1,2, -3, 4, 5
Interpret this patient's ABO and D type using the following results
Red Cells
Anti-A: 0
Anti-B: 4+
Anti-D 4+
A1: 3+
B: 0
O cells: 0
B positive
ABO/Rh blood type
Anti-A: 0/Anti-B: 0
A1: 4+/ B: 3+
Anti D 3+ Rh control 0
O positive
A recipient with group A phenotype requires a transfusion of 2 units of frozen plasma what types are appropriate to select for transfusion
AB and A
Patient cells with anti-A 4+, Patient with anti-B neg and patient cells with A1 cells 1+
cold autoantibody
Cell suspensions used is blood banking procedures are typically
3- 5%
Compatibility procedure will address what issues
prevent life threatening transfusion reactions
Maximize in vivo survival rate of red cells
check ABO compatibility
BUT NOT prevent antibody formation
When are Coombs control cells added
After the AHG reactions have been
Antibodies to Rh, MNS, Kell, or Duffy antigens may cause:
Acute hemolytic transfusion reaction
The Rh antisera that requires a parallel control is
High protein polyclonal
what antibody is present in the serum of a person who is group A
What are resolutions for an ABO discrepancy
Review patient history
repeat ABO testing with longer incubation at room temp.
repeat ABO testing with incubation at 4C
The most common cause of false-negative results in the antiglobulin test is
Inadequately washed red cells
The most serious transfusion reactions are due to incompatibility to which blood group system
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
Regarding the gel technique, which step is not performed
immediate spin
It would not be unusual for pregnant women to express which Lewis phenotype
Le (a-,b-)
What is source of antigen in routine blood bank procedures
Screening cells, Panel cells, and A1 and B cells
Rh system antibodies characteristically give
reactions that are enhanced with enzymes
reactions at 37 degrees
Unacceptable quality control results for the antiglobulin test performed in test tube may not be noticed if
the reagents used were improperly stored
the tech performing the test was never trained
preventive maintenance has not been performed on the cell washer
The expression of the gene that can be observed is called
A bombay individual would have which of the following ABO phenotypes
The test that uses IgG-sensitized red cells (check cells)
antiglobulin test
In an antibody identification panel only one red cell was negative at the antihuman globulin phase, on ruling out and matching the pattern an anti-k was identified what further testing is necessary to confirm the antibody
two more k-negative cells should be tested
The saliva of an adult whose red cells are shown to be group A Le(a-, b+) is expected to have
A, H, Lea and Leb substances
A antibody screen and computer crossmatch were peerfomed on a patient being admitted to the ICU with renal failure, The antibody screen is negative at AHG the blood bank tech calls, the hospital were teh patient had been transferred from and finds out the patient has a history of anti-E that was found about ten years ago, the blood bank tech who performed the computer crossmatch should now
proceed with a crossmatch at AHG phase and provide E negative units to this patient
An adult individual has a genotype of lele, Sese, HH what is the red cell phenotype
Le (a-,b-)
ABO blood group antigens are expresses at _____traits
When group O blood is not available for transfusion, what is the next alternative
An individual has the genotype AO, HH, what antigens would be present on the red cells of this individual
A and H
The antigens of the Cartwright blood group system are
Yta, Ytb
Most adults have strong ___antigen expression and weak___expression (hint: cord cells are the opposite)
I and i
A technologist identifies and anti-c the only antibody not yet ruled out is anti-E what is the next step for the technologist to take
test the patients serum against additional cells that are c- and E+
What is the most likely to account for a false-negative antigen-antibody reaction
excess antibody or antigen levels
Lele sese hh
Le(a+.b-) Bombay
Given the following results, determine the MOST likely cause(s) of the following ABO discrepancy
anti-a: 0/anti-b: 3+/anti-a,b: 3+
a cells:3+/B cells:4+/ O cells: 3+
room temperature reactive alloantibody
an individual who secretes A and H substances in his saliva must possess the following genes
A, H and Se
lele Sese
Lele Sese H
A patient who is phenotypically group B has which antibody in his/her serum
A patient in the ICU has had many blood transfusions over the past few days
anti-A: 1+mf/anti-B: 0/A1 cells: 0 A2 cells: 0/B cells: 4+/ Auto: 0/ DAT: 0
what is the MOST probable explanation for these results
group A patient transfused with group O blood
Le (a+,b-)
LeLe sese H
Le (a-,b-) Bombay
lele sese hh
A group O patient was crossmatched with group B red blood cells what phase of the crossmatch will first detect this incompatibility
Immediate spin (IS)
The weak D test detects
weak D antigen
anti H lectin
Ulex europeaus
pretransfusion testing begins with
proper identification of the patient
Infants do not require crossmatching if they are less than
4 months old
The indirect antihuman globulin test is incubated at what temp
the antiglobulin test was preformed using gel technology A button of cells was observed at the bottom of the microtube following centrifugation this result indicates a
negative reaction
mycoplasma pneumoniae infections can sometimes be associated with
anti-I antibodies
Using wiener nomenclature a patient has D, C,e how would this be written
Which procedure tests donor cells against the recipients serum and primarily functions to determine the ABO compatibility of the donor cells
major crossmatch
a positive antibody screen, negative autocontrol, and positive major crossmatch may be caused by
recipient alloantibody to donor cell antigens
Lewis antibodies are an example of
IgM antibodies that react on IS
When using low protein anti-D reagents an Rh control is indicated
when sample/donor unit types as AB positive
Persons who phenotype as Fy(a-b-) are resistant to infection by what organism
Plasmodium malariae
A patient needing a transfusion has a negative antibody screen in all phases of testing One out of four units crossmatched shows 2+ incompatibility at the AHG phase The most likely cause of this compatibility is
positive DAT in the donor
What reagent contains antibodies to multiple antigenic epitopes
the Donath-Landsteiner antibody is
an IgG auto anti-P
The frequency of the D-negative phenotype in the population is
High-titer,, low avidity antibodies typically
react with antigens of high frequency in the population
the phase of the agglutination reaction is important in the interpreation of the antibody screen or antibody identification panel because
indicates the class of antibody
when an individual is said to be group A it refers to the individuals
red cells that phenotype as S- s- are also
a group AB patient requires plasma the blood bank inventory indicates that no units of AB plasma are available for transfusion which of the following plasma ABO types is an acceptable substitute
No other ABO type is acceptable
antibody screening of the recipient is performed as a a component of compatibility testing to detect
red cell alloantibodies
High protein anti-D reagents
they contain approx 20% bovine albumin
increase the possibility of a false-positive reaction, requiring the use of a control
have been largely replaced with low protein monoclonal reagents
An agglutination reaction described as "many medium sized clumps, clear supernantant would be graded as
HTLA antibodies
are usually clinically insignificant
Group O cells are used as a source for commerial screening cells because
ABO antibodies do not react with group O cells
The antibody screen
detects most clinically significant antibodies
proteolytic enzymes should not be used to screen for antibodies because
some antigens are destroyed by enzymes, which would cause the antibodies to be missed
examination of a tube with an optical aid agglutination viewer shows one large clump with a clear background this should be graded as
which of the following blood group systems has been implicated in transfusion reactions on the first exposure to incompatible red blood cells
why is incubation omitted in the direct antihuman globulin test
the antigen antibody complex has already formed in vivo
antibodies deteced in the Immediate spin crossmatch are usually of which of the following classes of immunoglobulin classes
Polyspecific AHG contains which of the following components
Anti-IgG and C3
A person whose red cells type as M+ N+ with antisera would be
The genotype of two parents areas follows:
Mother: dd
Fater: Dd
D is dominant and d is recessive. which of the following probability of genotypes is possible in this offspring
50% Dd; 50% dd
In the process of identifying an antibody the tech observed 2+ reactions with 9 of the 10 cells in a panel at the IS phase these reactions disappeared following incubation at 37C and the antihuman globulin phase of testing the antibody most likely to be responsible is
The D antigen of the fisher-race nomenclature corresponds to which of the following antigens ofteh Wiener nomenclature
Characteristics of IgM antibodies include
reacts best at room temp or lower
does not cross the placenta
has the potential to bind 10 separate antigen sites
Check cells are used to determine the validity of testing at the AHG phase and check for what errors
omission of AHG sera from the test
inadequate washing of cells
contaminated saline
DTT destroys antigens off which blood group
What immunofominant sugar is responsible for H specificity
Anti L-W reacts strongest with which cell
D positive
The immunoglobulin class of anti-M antibodies is
Frequently a mixture of IgG and IgM
ABO reverse grouping consists of
cells of known antigen and serum of unknown antibody
A person with the phenotype Cc is
C single dose, c single dose or heterozygous
clinically significant antibodies occur in approx
3% of the population
Cold autoantibodies are typically of which specificity
ABO forward grouping consists of
Cells of unknown antigen and serum of known antibody
a tech encounters a cold-reacting antibody that reacts at room temp IS with all of teh antibody identification panels testing with cord cells shows a negative result the antibody is most likey
if the autocontrol and all antibody pane cells agglutinate at room temp but react less strongly at 37C in the AHG phase you might suspect
cold reacting autoantibodies
the AABB standards require that all insitiutions issung blood to recipients for transfusion retest the donor blood what is required to be retested
ABO typing on all units; D typing on Rh neg units
MOST likely ABO discrepancy

anti-a:4+/anti-B 0/Anti-AB 4+/A1 2+ A2 0/B 4+
group A2 with anti-A1
A patient was transfused two weeks before his current testing results indicates a positive DAT and a positive antibody screen with screening cell 1 and 2 at IAT the autoantibody may be removed from the serum using
allogenic adsorption
The Du antigen
is a weakened form of the D antigen
Characteristics of Kidd antibodies:except
IgG immunoglobulin ability to bind complement show delayed HTR
what is the action of AHG reagent
cross links RBCs that have become sensitized with antibody or complement
A gene that produces no detectable product is referred to as
an amorph
characteristics of the ABO blood group antibodies include
they are naturally occuring and are mostly IgM
which autoantibody specificity is found in patients with paraoxsmal cold hemoglobiniuria
antibodies to Rh, MNS, Kell or Duffy antigens may cause
Acute hemolytic transfusion reactions
which reagent would you use to preform reverse typing to identify the presence of ABO antibodies in the patient's serum
A1 and B cells
Most clinically significant antibodies against blood groups are
Most likely ABO discrepency
anti-a: 4+/anti-b 0/anti-ab 4+/A1: 0 A2 0/ B: 0
Elderly or immunocompromised patient
which antigens are not destroyed by enzymes
MNSs and Duffy
which of the following phenotypes will react with anti-f
a patients phenotype consists of the following typing results D+, C+, E-, c-, e+, S-, s+
which alloantibodies is the patient capable of forming
anti E, c, S
what is the name of the procedure in which the antibody is removed from the surface of a red cell destroying the cell
the two A main subgroups A1 and A2 can be differentiated by using reagent made from
Dolichos biflorus
an antibody that is typically enhanced by treatment with proteolytic enzymes is
Kidd and Rh
when beginning the antibody exclusion process after testing a panel of RBCs the tech should first
start ruling out the first non-reactive cell on the panel
the immunogominant sugar that confers B blood group specificity is
compatibilty testing for neonates can be performed using plasma from
biological mother
which antibodies can either be IgM or IgG and is often detected by incompatible crossmatch
how would you interpret the results if both the anti-D reagent and the Rh control were 2+ agglutination reactions
invalid, unable to determine without further testing
which red cell antigens are found on glycophorin-A
Serum ABO grouping is not routinely performed on newborns because
infants lack ABO antibodies until about 4 mths of age
most causes of autoimmune heolytic anemias (AIHA) are
warm AIhA
prozone occurs when
antibody molecules are in excess of antigen
which red cell typing would most commonly be found in the black donor population
Fy (a-b-)
Js (a+b+)
anti-I will react routinely with
all adult red cells
which antibodies is typically IgG shows dosage and shows no reactivity with enzyme treated cells
Duffy (Fya and Fyb)
give examples of conditions that would exhibit a positive DAT