D Typing and Weak D Flashcards
True of False: D antigen is the most immunogenic of all blood group antigens
True
What antigen is the most immunogenic out of all the blood group antigens?
D
Is the D antigen present at immediate spin or AHG?
Both.
Weak D, however, is negative at immediate spin but positive at AHG.
When is weak D detected?
Usually at AHG phase. Not detected at immediate spin.
What must the D control show in order for the Weak D testing to be considered positive at AHG?
D control must be negative
True or false: ALL DONORS MUST be tested through AHG or with a sensitive weak D method.
True
Do blood recipients have to be tested for weak D?
No. They are considered D negative at immediate spin and can receive D negative blood products.
Who must be tested for weak D?
- Blood donors
- Infants of D negative mothers
How would you report a weak D positive result?
“D positive”
What is the monoclonal/polyclonal Anti-D control used in weak D testing?
All the components of the reagent Anti-D serum with NO Anti-D antibody.
Run Anti-D control alongside regular Anti-D testing to make sure nothing is spontaneously agglutination (Anti-D control should always be negative.)
When would you need to use the D control?
For any AB positive and for any ABO type negative at immediate spin for the D antigen
Carry testing through to AHG for weak D typing
If patient is AB positive, what controls would you use?
6-8% albumin control, autocontrol, or DAT
» Patient’s A&B cells typed with reagent Anti-A and Anti-B will be positive in an AB positive patient… no negative control
(A negative Anti-D control rxn with Anti-A and/or anti-B in pt is the negative control; pts cells are not spontaneously agglutinating)
What is the most common cause of a positive Anti-D control?
a positive DAT!
normally Anti-D control should be negative.
