Rh Blood Group Flashcards
(68 cards)
it takes how many ml of FMH to isoimmunize the mother?
atleast 0.01mL
when is Rho(D) immune globulin given to the pregnant woman?
before 12 weeks
a mini-dose of 150 mcg Rho(D) immune globulin will suppress immune response to how much Rh+ RBCs?
2.5 mL
after 12 weeks, how much dose of Rho(D) immune globulin is recommended?
300mcg
A standard dose of Rho(D) immune globulin (300 mcg) covers FMH up to
15mL fetal RBC
HbF is resistant to
alkali denaturation
is an acid-elution assay performed on maternal blood to determine the amount of HbF that has passed into the maternal circulation
Kleihauer-Betker Test
the smear in KB method is stained via what method?
Shepard’s method
The fetal red blood cells are left ____ in color, and the maternal cells appear ____due to the absence of staining.
rose-pink “ghost-like”
How many cells are counted in KB test?
2000 cells
formula used to estimate total amount of FMH
percentage of fetal cells = number of fetal cells X 100 / total number of RBCs.
is a qualitative screening test performed on a maternal blood sample to determine if FMH has occurred between an Rh-positive fetus and an Rh-negative mother and serves as a useful screening test.
Rosette test
The rosette test is performed by incubating the Rh-negative maternal venous whole blood sample with____
anti-Rho(D) immune globulin
In rosette test, enzyme treated indicator cells are added, only binding to the fetal cells that were present and sensitized, resulting in a process called
erythrocyte rosetting pattern
threshold of KB test
5 mL (thus, highly specific but with low sensitivity)
One vial of Rho(D) immune globulin contains ___mcg and protects against ___mL of fetal blood.
300 30
Volume (mL) of fetal blood formula:
Volume (mL) of fetal blood = Percentage of fetal cells x 50
Number of Vials of 300 mcg RhIG required formula:
Number of Vials of 300 mcg RhIG required = Volume of fetal blood/30 mL
combined equation: number of vials
Number of vials* = Percentage of fetal cells x 50 / 30
number of agglutinates to render positive in rosette test and suggests a significant FMH (>30 mL)
3 or more in 10 fields or 7 or more in 5 fields
indicator red cells used in Rosette test which will bind to the antibody-coated infant RBCs causing agglutination
ficin treated R2R2
RHD pseudogene (Rh—) commonly in
Africans
Del (Rh—) commonly in
Asians
RoRo genotype commonly in
African Americans