Routine Testing Flashcards
single most important in vitro immunologic reaction
hemmagglutination
2 stages of hemmagglutination
1) sensitization
2) lattice formation
antigen source of ABO/D typing
patient’s red blood cells
antigen source of ABO serum testing
reverse grouping cells
antigen source of antibody screen
screening cells
antigen source of antibody panel/identification
panel cells
antigen source of crossmatch
donor red blood cells
antibody source of ABO serum testing, Ab screen and ID and crossmatch
patient’s/recipient’s serum/plasma
responsible for the regulation of blood banking reagents
food and drug administration (FDA)
unique recognition of of antigen and antibodies (from reagent)
specificity
strength of antigen-antibody reaction (from reagent)
potency
when will quality control for reagents be done?
daily
ideal characteristics of antibody reagents
concentrated
highly specific
well-characterized
uniformly reactive
general rule of adding reagents and samples
clear solutions first then RBCs
make sure both are added to the solution
Anti-A dye
bromphenol blue
thymol blue
potent blue
anti-B dye
acroflavin
preservative of anti-A and anti-B reagents
sodium azide
most important Rh antigen
D antigen
ensures correct interpretation of typing results
reagent controls
confirms forward ABO typing
reverse typing/serum/plasma typing
composition of screening cells and panel cells
phenotyped O cells
detects the most clinically significant red cell antibodies
screening cells
contains most frequently inherited red cell antigens
panel cells
exhibits dosage effects
"Rich deaf kid & men loath" Rh (except D) Kidd Duffy MNS Lutheran
enhanced in enzyme
"KRhIPLe" Kidd Rh I P1Pk Lewis
destroyed by enzymes
Duffy
MNS
unaffected by enzymes
Kell
reagents that denature Kell
AET
DTT
ZZAP
2-ME
antibody that can react at any phase
Lewis
antibody enhanced by acidification
M
antibody enhanced by alkalinization
N
antibody that is a common cause of anamnestic repsonse
Kidd
antibodies optimal at room temperature (immediate spin phase)
I, H, IH MN P1 Lea, Leb Lua
antibodies optimal at 37C
D, E
K
antibodies optimal at antiglobulin phase
Rh K Duffy Kidd Ss Lub Xga
masks clinically significant antibodies, typically weak and often diluted out to relatively high titer despite the weak reaction
high titer, low avidity antibodies (HTLA)
most common HTLA
Chido/Rogers
described the PRINCIPLE of antiglobulin technique
Carlo Moreschi
INTRODUCED the antiglobulin test
Coombs, Mourant and Race
sensitivity of the AHG reagent
100 to 500 IgG per RBC
400 to 1100 C3d per RBC
AHG ratio of serum to cells
40: 1 (2 drops to 5% RCS)
133: 1 (4 drops to 3% RCS)
sample of choice for DAT
whole blood in EDTA
sample of choice for IAT
serum/plasma
when is DAT requested?
HTR
HDFN
AIHA
DIHA
when is IAT requested?
weak D crossmatch antibody screen antibody titration red cell phenotyping
AHG reagent primarily used in DAT
polyspecific AHG
AHG reagent primarily ised in DIFFERENTIAL DAT
monospecific AHG
potential reasons for a false negative result upon addition of check cells
WAR
failure to WASH
failure to ADD reagent
failure to REACT
increases the rate of antibody uptake
LISS
components of LISS
NaCl
glycine
salt-poor albumin
LISS serum to cell ratio
40:1
reaction time of LISS
5-15 mins
concentrates the antibody in the test environment
PEG
reaction time of PEG
10-30 minutes
adjusts the zeta potential of RBC
BSA
reaction time of BSA
15-60 minutes
removes negative charges from RBCs
enzymes: papain from papaya ficin trypsin bromelin from pineapple
concentration, pH of NSS
0.85% to 0.9%, pH 6.5 to 7.5
pH of phosphate buffered saline in NSS
pH 7.2 to 7.4
also known as column agglutination
gel testing