Haematology 1

Question 0

Group A blood type

Answer 0

Red blood cell type-> A
Antibodies in plasma-> anti B
Antigens in RBC-> A
Genotype AA or AO

Question 1

Blood group O

Answer 1

Red blood cell type-> O
Antibodies in plasma-> anti A and B
Antigens in red blood cell-> none
Genotype OO

Question 2

Group B blood type

Answer 2

RBC type-> B
Antibodies-> anti A
Antigens-> B
Genotype BB or BO

Question 3

Group AB

Answer 3

RBC-> AB
Antibodies-> none
Antigens-> A and B
Genotype AB

Question 4

ABO blood group system

Answer 4

A,B,O genes on chromosome 9
Oligosaccharide attached to membrane glycoprotein/lipid
A,B,H antigens present on most cells
80% secretory
FUT1 (H gene)-> Bombay phenotype-> O type RBC but anti H,A and B
Variable numbers of antigens per cell create sub groups

Question 5

ABO inheritance

Answer 5

O is recessive
A and B dominant
-> produce co dominance in AB

Question 6

AB(H) antibodies

Answer 6

Landsteiners law-> presence of Ag on cell implies abscenc of corresponding Ag in serum and the presence of opposite Ag
Naturally occurring IgM
IgG alloantibody-> can cross placenta
Bind complement at 37 degrees-> RBC lysis

Question 7

Rhodes blood system

Answer 7

50 antigens 
RhAG-> Rh-associated glycoprotein-> transmembrane polypeptide 
RBC's only
Fully developed at birth 
IgG antibodies immune

Question 8

Rh inheritance

Answer 8

Locus consists of two closely linked genes
-> RhD gene-> codes for a single protein-> RhD antigen
-> RhCcEe-> alternative splicing in to 3-> E or e antigen, other two C or c epitope
Some individuals don’t have RhD gene-> Rh negative-> cde/cde

Question 9

Haemolytic disease of the new born

Answer 9

RhD negative mother and RhD positive fetus
Fetal RhD positive cells enter the maternal circulation-> anti D is produced by and immune response in the mother-> IgG anti D crosses the placenta-> haemolysis
Maternal IgG alloantibodies-> first pregnancy unaffected as not sensitised
Anti A, B rare
Intrauterine death/hydrous fetalis
Anaemia, jaundice
Antenatal anti-D (Rh immunoglobulin) for RhD negative, anti D negative mother -> binds any fetal cells with D antigen before mother is able to produce an immune response

Question 10

Blood group serology

Answer 10

Ensure no Ag/Ab reaction that leads to haemolysis
Based on antigens on RBCs and antibodies in serum
Platelet compatibility O+ or - etc use same or close match
Plasma product compatibility use same, O can have anything

Question 11

Forward group test

Answer 11

Red cells are suspended in saline agglutinate and exposed to various antigens to see if there is agglutination

Question 12

Direct anti globulin test

Answer 12

Take blood from patient
Add anti IgG-> agglutination
red cells are too far apart for IgG antibodies to cause direct agglutination

Question 13

Indirect anti globulin test

Answer 13

Antibody screen
Patients serum (antibodies) with transfusion blood-> antigen binding
Add antibodies-> agglutination?

Question 14

Red cell compatibility testing

Answer 14

Cross match

Immediate spin of IAT of pt serum and donor RBCs

Question 15

Adverse effects of transfusion immune

Answer 15

Allo-immunisation 
Acute haemolytic transfusion reaction 
Delayed HTN
Anaphylaxis 
Transfusion related acute lung injury 
Post transfusion purpura
Transfusion associated GVHD

Question 16

Adverse effects of transfusion non immune

Answer 16

Transfusion transmitted infections-> bacterial, viral, protozoan, vCJD
TACO-> fluid overload, hyper viscosity-> over transfusion
Transfusion associated dyspnea
Febrile non haemolytic transfusion reaction
Iron overload
HBV and HCV 3.5 per 100000
HIV 0.9 per 100000