Immunohematology Flashcards
RBC carbohydrate antigens tend to stimulate what type of Ig?
IgM
RBC protein antigens tend to stimulate what type of Ig?
IgG
which Ig can cross the placenta? which Ig cannot?
- IgG
2. IgM
which RBC antigen forms the building block for a person to be any blood type other than O?
H antigen
what is the Bombay phenotype?
lack of H antigen on RBCs
if you have just the H antigen, what blood type must you be?
O
what is the universal donor for transfusing RBCs? why?
O - only H antigens
which blood group forms neither A nor B antibodies?
AB
what is the rarest blood type?
AB
what is the main antigen of the Rh system?
D
how does hemolytic disease of the fetus and newborn work?
- mom is Rh negative
- baby is Rh positive
- mom makes antibodies to D antigen for first pregnancy
- upon second pregnancy, D antibodies attack the D antigens on baby’s RBCs
what is RhoGAM? what does it do?
- anti-D Ab given to mother prior to first birth
2. removes D positive RBCs from baby before immune system forms antibodies
what is front type?
commercially made antisera that is mixed with patient RBCs to determine anti-A/B phenotype
what is back type?
commercially made RBCs that are mixed with patient plasma to determine presence of anti-A or anti-B antibodies
what tests are required for confirmation of blood type?
front type and back type
what does the direct antiglobulin test (direct Coomb’s test) detect? what type of sample is used?
- in vivo auto or alloantibody sensitization - IgG and/or complement on RBCs
- patient RBCs are used
what is a common cause of a positive DAT?
medications
what does the indirect antiglobulin test (indirect Coomb’s test) detect? what type of sample is used?
- detects in vitro antibody sensitization - unexpected Abs, cross matching
- uses patient serum / plasma mixed with random donor RBCs
a D positive patient can receive which Rh blood types?
D positive or D negative
a D negative patient can receive which Rh blood types?
only D negative (except in emergencies)
what type of RBCs can a type A patient receive?
A and O
what type of RBCs can a type B patient receive?
B and O
what type of RBCs can a type AB patient receive?
AB, A, B, and O
what type of RBCs can a type O patient receive?
only O
what is the universal donor for plasma?
AB
what type of plasma can a type A patient receive?
A and AB
what type of plasma can a type B patient receive?
B and AB
what type of plasma can a type AB patient receive?
AB
what type of plasma can a type O patient receive?
O, A, B, and AB
what % of people who are D negative and given D positive blood will develop the anti-D Ab?
50-70%
what is the universal blood type recipient?
AB
