ABO Typing Discrepancies
Antigens and antibodies specifically combine to form immune complexes. What term refers to the antibody's attraction to a particular antigenic determinant (epitope)?
Define:van der Waals forces
ABO Typing Discrepancies
Antigens and antibodies specifically combine to form immune complexes. What term
refers to the antibody's attraction to a particular antigenic determinant (epitope)?
ANSWER- Affinity
Define: Affinity ANSWER- the strength of attraction that an antibody and antigen
possesses, which results in the formation of an immune complex.
Define: Avidity ANSWER- the strength of the bond between the antibody (paratope)
and antigenic determinate (epitope). This happens as a result of the immune complex
formation.
Define:van der Waals forces ANSWER- are the sum of attractive or repulsive forces
surrounding the red blood cell (RBC). These forces are important to creation of the
immune complex.
Define: Zeta potential ANSWER- is the overall ionic charge that surrounds the RBC. It
functions to repel RBCs from each other. Zeta potential must be overcome in order to
achieve agglutination.
Antigen ANSWER- In the postzone there is an excessive amount
Rbc membrane proteins
May or may not be considered an immunogen
Antibody ANSWER- In the prozone there is an excessive amount
These can be naturally occurring or produced after stimulation
They are soluble and found in plasma
There are 5 general classes
A patient's pretransfusion ABO grouping results are as follows:
Forward (Cell) Grouping
Anti-A= 4+
Anti-B=0
Anti-A,B=4+
Reverse (Serum) Grouping
A1 Cells=0
, B Cells=0
What is the MOST likely ABO group for this patient and what ABO typing discrepancy is
most descriptive of these findings? ANSWER- Patient is most likely Group A;
Unexpected reactions in forward typing
Forward (Cell) Grouping
Anti-A= 4+
Anti-B =0
Anti-A,B =4+
Reverse (Serum) Grouping
A1 Cells =0
B Cells =0 ANSWER- Category: Group l-- Discrepancies that are associated with
unexpected or missing/atypically weakened reactions in the reverse typing.
Most probable ABO type: Group A
Possible causes: Immunocompromised, age-related, transplantation, dilution,
technical/procedural error
Some strategies for resolution: Repeat testing with careful attention to accuracy or
repeat reverse typing with extended incubation at or below room temperature. Weak
ABO reactions can often be potentiated using extended incubation at or below room
temperature.
B Cells 4+ ANSWER- Group II - Discrepancies that are associated with unexpected or
atypical reactions in the forward grouping, specifically mixed field reactions.
Most probable ABO type: Group A
Possible Causes: Weak subgroup of A, notably A3; weak results with mixed field
reaction in the forward typing could be due to the transfusion of large quantities of O
Red Blood Cells into a group A recipient, chimerism, or a group A patient transplanted
with group O stem cells.
The benefits of buying summaries with Stuvia:
Guaranteed quality through customer reviews
Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.
Quick and easy check-out
You can quickly pay through credit card or Stuvia-credit for the summaries. There is no membership needed.
Focus on what matters
Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!
Frequently asked questions
What do I get when I buy this document?
You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.
Satisfaction guarantee: how does it work?
Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.
Who am I buying these notes from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller smartchoices. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for $10.29. You're not tied to anything after your purchase.
