4.3 Rh Blood Group System Flashcards
A complete Rh typing for antigens C, c, D, E, and e revealed negative results for C, D, and E. How is the individual designated?
Rh negative
How is an individual with genotype Dce/dce classified?
Rh positive
If a patient has a positive DAT, should you perform a weak D test on the cells?
No, the cells are already coated with antibody
Which donor unit is selected for a recipient with anti-c?
A. r´r
B. R0R1
C. R2r´
D. r´ry
r´ry
Which genotype usually shows the strongest reaction with anti-D?
D–/D–
Why is testing for Rh antigens and antibodies different from ABO testing?
ABO reactions are primarily caused by IgM antibodies and usually occur at room temperature; Rh antibodies are IgG and agglutination usually requires a 37°C incubation and enhancement media
Testing reveals a weak D that reacts 1+ after indirect antiglobulin testing (IAT). How is this result classified?
Rh-positive
What is one possible genotype for a patient who develops anti-C antibody?
A. R1r
B. R1R1
C. r’r
D. rr
rr
A patient developed a combination of Rh antibodies: anti-C, anti-E, and anti-D. Can compatible blood be found for this patient?
rr blood could be used without causing a problem
A patient tests positive for weak D but also appears to have anti-D in his serum. What may be the problem?
A D mosaic may make antibodies to missing antigen parts
Which offspring is not possible from a mother who is R1R2 and a father who is R1r?
A. DcE/DcE
B. Dce/DCe
C. DcE/DCe
D. Dce/dce
DcE/DcE
Which weak D phenotypes necessitate Rh immune globulin (RhIg) prophylaxis:
1, 2, 3, none of the above
None of the above
What antibodies could an R1R1 make if exposed to R2R2 blood?
Anti-E and anti-c
What does the genotype —/— represent in the Rh system?
Rhnull
What techniques are necessary for weak D testing?
37°C incubation + IAT
A patient types as AB and appears to be Rh positive on slide typing. What additional tests should be performed for tube typing?
Rh negative control
According to the Wiener nomenclature and/or genetic theory of Rh inheritance:
There are multiple alleles at a single complex locus that determine each Rh antigen
The Wiener nomenclature for the E antigen is:
rh”
A physician orders 2 units of leukocyte-reduced RBCs. The patient is a 55-year-old male with anemia. He types as an AB negative, and his antibody screen is negative. There is only 1 unit of AB negative in inventory. What is the next blood type that should be given?
A negative
Which technology may report an Rh-weak D positive as Rh negative?
A. Gel system
B. Solid phase
C. Tube testing
D. None of these options
Gel System
