7,8,9 Flashcards
Is performed to determine whether the antibody identified is an alloantibody, autoantibody or both.
Autocontrol
Used to strengthen and destroy antibodies in order to differentiate between multiple potential antibodies.
Proteolytic enzymes
A series of reagent red cells from different donors that have been antigen typed for common red cell antigens.
Antibody identification panel
Used to prove the presence or absence of the corresponding antigen on the red cells of the patient. Can be complicated when the patient has been transfused or has a positive DAT.
Phenotyping
The first step of an antibody identification, in which, reactions of a test panel are compared to a chart(antigram)that lists the antigenic composition of each panel cell
Elimination method
Panels used when additional cells are needed to rule out antibodies after performing an antibody identification panel
Select cells
Any antibody that shortens the survival of transfused red cells or that has been associated with hemolytic disease of the newborn
Clinically Significant antibody
When using the elimination method which antibodies can be eliminated?
Non reactive cells and cells heterozygous for Ag showing dosage
When using the elimination method why is it important to take special precautions when eliminating the following Antibodies: Rh, Duffy, Kidd, MNSs?
They may result in false negative reactions
What may different reaction strengths or reactions in different phases of testing indicate?
Multiple antibodies or may represent antibody showing dosage
TRUE OR FALSE:
Select cells CANNOT be used past their expiration date
False ; should not but not always possible
What is the rule of three in regards to antibody ID?
Proper ID of antibody requires sufficient positive and negative cells to ensure a pattern is not due to chance. A minimum of three cells with the antigen and three cells without the antigen are required. Ensures that the reaction pattern is not the result of the presence of a low incidence or high incidence Antigen.
What is the likely antibody class if the antibody reacts in the : Albumin/AHG phase? Saline phase?
Albumin/AHG: most likely IgG
Saline: most likely IgM
TRUE OR FALSE:
An antibody identification panel is a series of reagent red cells from different donors that have been antigen typed for low-incidence red cell antigens
False ; high incidence red cell antigens
What is an antibody identification auto control used to determine?
If there are patient alloantibodies or autoantibodies
If an antibody identification auto control is positive; what is the next step the blood bank technician should take?
Verify the patient history and perform a DAT
Utilizing the elimination method for an antibody identification, a technician will eliminate antibodies when the patient results (on any phase of testing) is \_\_\_\_\_\_\_\_\_\_ and the antibody is \_\_\_\_\_\_ on reagent cells. A) positive; present B) positive; absent C) negative; present D) negative; absent
C) negative; present
Antibody identification antigens showing dosage that are ____________ may result in false ___________ reactions and should be eliminated with caution.
A) Heterozygous; negative
B) Heterozygous; positive
C) Homozygous; negative
D) Homozygous; positive
When performing an antibody identification a blood bank technician is able to rule out all but three antibodies; what is the technicians next step?
Perform a selected cell panel from other cell panel lots, even if the lots are expired
When performing an antibody identification a blood bank technician is able to rule out all but two antibodies. The remaining antibodies are anti-C and anti-N; what is the technicians next step?
Repeat test using papain(proteolytic enzyme)
When performing an antibody identification a blood bank technician is able to rule out all but one antibody. The remaining antibody was present on nine panels and absent on two panels, with the corresponding patient results. Can the technician accept these results for antibody identification?
No, a minimum of 3 absent panels are needed
A ________ is a procedure that frees antibodies that are coating RBCs.
Elution
A__________ is a procedure that removes antibodies from serum.
Adsorption
An elution can be used to:
A) investigate a positive DAT
B) Concentrate and purify
antibodies
C)Remove cold/warm reacting antibodies from RBCs
D) all of the above
D
TRUE OR FALSE:
An acid illusion is preferred over a Heat/Lui Freeze Thaw elution due to its ability to be utilized and identification of all possible antibodies.
False
If the Saline from the final wash of the cell wash for an elution tested positive for antibodies; what does it tell the blood bank technician about the eluate?
The elution is invalid because it may contain Antibodies other than what was bound to the patient RBCs
Adsorption procedures are used to:
A) Confirm the presence of antigens on RBCs through their ability to remove a specific serum antibody
B) Confirm specificity of an antibody by showing that it can be absorbed only by RBCs of a particular group phenotype
C) Separate multiple antibodies present in a single serum sample
D) All of the above
D)
Pre-Transfusion testing is used to: A) detect most clerical errors B) detect all ABO grouping errors C) detect Rh typing errors D) Guarantee normal survival of the transfused cells
A)
TRUE OR FALSE:
Pre transfusion testing includes weak D testing of the recipients blood.
False
What is the minimum patient identifiers required when collecting samples for pre-transfusion testing?
Two patient identifiers
How many days prior to transfusion may samples for pre-transfusion testing be collected?(history of pregnancy and/or previous transfusion is unknown)
Three days
Choose the possible compatible units for transfusion; Patient blood type is B negative:
A) O positive (pRBCs) B) O negative (pRBCs) C) B positive (pRBCs) D) B Negative (pRBCs) E) Only A & C F) Only B & D G) All of the above
F) Only B & D
Choose the possible compatible units for transfusion; Patient blood type is B negative:
A) O positive (FFP) B) O negative (FFP) C) B positive (FFP) D) B Negative (FFP) E) Only A & C F) Only B & D G) All of the above
F) Only B & D
Choose the possible compatible units for transfusion; Patient blood type is B negative:
A) A positive (platelets) B) A negative (platelets) C) B positive (platelets) D) B Negative (platelets) E) Only A & B F) Only C & D G) All of the above
G) All of the above
Choose the possible compatible units for transfusion; Patient blood type is B negative:
A) A positive (cryo) B) A negative (cryo) C) B positive (cryo) D) B Negative (cryo) E) Only A & B F) Only C & D G) All of the above
G) All of the above
What is the maximum acceptable age of blood for transfusion to a pediatric recipient?
14 days
What are acceptable anticoagulants for transfusion to infants less that 4 months of age?
CPDA-1 and CPD
What blood product should be used if a patient is at risk of contracting CMV(seronegative) but CMV seronegative units are not available?
Leukoreduced products
What blood product should be used if a patient is severely immunosuppressive down and at risk for transfusion related graft vs host disease?
A) Irradiated products
TRUE OR FALSE:
Immediate spin cross matches are permitted when the recipient has a negative antibody screen and negative antibody history
True
What is another name for antibody ID?
IAT ; Antibody panel
How long is a type and screen considered valid?
72 hours
What are the 3 phases in an antibody screen?
Immediate Spin ; 37 degrees ; AHG
What ABO group are reagent cells?
Group O
What is an antigram?
Chart that lists the antigenic composition of each panel cell
What is a homogeneous and heterozygous cell?
Homo- 2 alike alleles
Herero- 2 different alleles
Under what circumstance will a homozygous cell be preferred over heterozygous?
To rule out antibodies
Name and describe the types of AHG
Poly specific/ clonal (contains anti-complement & anti-IgG components)
Anti IgG(anti- IgG w/ no anti complement)
Anti-complement(contains only antibodies active against designated complement components w/o any anti-IgG activity)
TRUE OR FALSE:
Agglutination at ANY stage of testing is considered a positive reaction.
True
Once an antibody is detected, what information should be considered when identifying the antibody?
The phase it was identified in
How do we ID antibodies?
Antibody ID Panel; rule in rule out
If a patient has an antibody should they have the corresponding antigen present in their red cells? Why or why not ?
No because if they do, it would be an autoantibody
Will all antibodies be detected during a routine antibody screen? Explain.
No, only “Clinically Significant Antibodies “ are of concern.
Name two ways to remove cold antibodies
Elution and Adsorption
