Final Flashcards
List the reagents and patient specimen used in an antibody screen.
Reagents: screening cells, LISS, and check cells
Specimen: patient serum or plasma
What is the purpose of the DAT, i.e. what does it detect?
Detects antibodies and complement attached to RBCs in vivo
– HDN, HTR, AIHA
List the components of DAT
- patient cells
2. AHG
If a Rh control tube is necessary in the Rh testing, and it is positive, the interpretation of the Rh type is what?
Invalid
Name and differentiate the two types of AHG that can be used in BB
- Broad spectrum/ polyspecific: contains both anti-complement (C3d) and anti-IgG
- Monospecific:contains either, but not both
What is the purpose of the IAT, i.e. what does it detect?
Detects antibodies and complement attached to RBCs in vitro
– used for XM and to screen cells
List the components of IAT
- patient serum
2. screening cells
Name two blood bank procedures that incorporate the IAT
- crossmatching
2. Antibody screen
List the steps in D^u testing, including the tubes included in the test.
Tubes: D test and Rh control test tubes
- Incubate both tubes at 37C for 15 mins
- Wash cells 3 times with saline
- add 2 drops of AHG to each tube and mix
- Centrifuge on high for 15 seconds
- Add 1 drop of check cells to any non-reactive tubes (results should be +)
(IWACA - to help remember the steps thanks to Angie!!!)
In the fetal bleed screening test, the presence of agglutinated cells indicates that the maternal blood contains a significant number of what?
Rh positive fetal cells
What term is used to describe the agglutination that constitutes a positive test?
rosettes
What test is used to determine the amount of fetal cells present in the maternal circulation.
Kleihaure- Betke Test
The AABB requires that Rh ____ mothers who have Rh ____ babies have the fetal bleed screening test performed.
Rh negative mothers with Rh positive babies.
If a mother is Rh negative and has a baby that is Rh positive name three situations that may warrant the Kleihaure- Betke Test to be performed.
Abortion
trauma
miscarriage
List 4 conditions that DAT can be used to detect.
- HDN
- AIHA
- HTR
- Drug-induced RBC sensitization
List the components of an auto control.
Patient red cells and
Patient serum
Two cell populations in a patients specimen can produce _______ agglutination.
Mixed field agglutination
The components of a forward ABO grouping are what?
Anti-A and anti-B antiserum and
patient cells.
The components of a reverse ABO grouping are what?
Patient serum and
A1 and B cells
What can be done to enhance an ABO reaction that is very weak upon immediate spin?
Sit at room temp for 30 mins or
Incubate at 4C
What blood bank procedure is used to resolve a positive DAT?
Elation
What blood bank procedure is used to resolve a positive antibody screen?
Antibody panel
Clinically significant antibodies are Ig__ antibodies which like to react at ____C and in the ____ phase.
IgG
37C
AHG
In a pregnant female, what antibody class is clinically significant?
Rh- IgG
Why? If the mother is Rh neg and baby is pos it could cause HDN, (sensitization of D antigen of fetal cells)
What are the two AABB requirements for routine crossmatching?
- Demonstrate ABO incompatibility
2. Demonstrate clinically significant Ab
The ____ is on the patient’s RBC; the ____ is in the patient’s serum
Antigen on RBC
Antibody in serum
Why is the washing procedure before the addition of AHG so important?
To prevent neutralization of AHG by globulins in the blood
FFP of the AB group is compatible with what blood group recipients?
All blood groups because AB plasma doesn’t have any antibodies
Jk^a and Jk^b
Phenotypes #23
Pt 1: Jk(a= b=)
Pt 2: Jk(a+ b+)
Pt 3: Jk(a+ b=)
Pt 3 is heterozygous
Pt 2 is homozygous
ABO compatible units # 24
O can only have O
B can have B and O
A can have A and O
AB can have A, B, AB, and O
(O is the universal donor where as AB is the universal recipient)
Blood group types # 25
Blood group types # 25 1. O pos
- A neg
- B Rh control pos- unable to interpret
- A pos with possible A subgroup
- AB pos
- A neg with possible A subgroup or A transfused with O
After the Coombs control cells are added to a negative AHG and the tube remains negative. What can explain this?
After the Coombs control cells are added to a negative AHG and the tube remains negative. What can explain this? 1. AHG was inactive
2. AHG was neutralized
Because RBCs not washed adequately
(Test needs to be repeated because the results are invalid)
