II. Definitions
III. Background
- Blood agglutinates (forms Antibody-Antigen clumps) if exposed to Antibody to Antigens on it's cell surface
- See Hemagglutination
- Antigens are known as Agglutinogens (e.g. Type A Antigen, Type B Antigen)
- Antibodies are known as Agglutinins (e.g. xA, xB, xRh)
- RBC with Blood Type O will agglutinate (Transfusion Reaction) if exposed to Antibody to Type A or Type B Blood
IV. Types: ABO Blood Types (H Antigen on RBC surface)
- Blood Type A
- Presence of Group A Antigen on RBC surface
- Blood Type B
- Presence of Group B Antigen on RBC surface
- Blood Type AB
- Blood Type O
- Absence of Blood Group A Antigen and Group B Antigen on RBC surface
- Universal Donor (can donate to any Blood Type on Blood Transfusion)
- Can only receive Blood Type 0 on Blood Transfusion
V. Types: Rhesus (Rh, D)
- Rhesus group (Rh) includes 50 Antigens of which only 5 are important
- Rh status (Rh+ or Rh-) refers to D Antigen which is the most important Antigen
- Rh (xD) is of critical importance in maternal and child health
- Mothers without Antibody to xD (Rh-) are at risk of sensitization to Rh if fetus is Rh+ (from father)
- Mother who forms Antibody to Rh during one pregnancy will react to future Rh Positive fetus
- Rh Sensitization results in future pregnancy Hemolytic Disease of the Newborn (Erythroblastosis Fetalis)
- RhoGAM is given during pregnancy to prevent Rh Sensitization
VI. Types: Other Important Minor Blood Groups
- Kell
- Duffy
- Fy Glycoprotein on surface of Red Blood Cells has 2 main Antigens (Fy-a, Fy-b)
- Risk of Hemolytic Transfusion Reactions
- Kidd
- Kidd Antigen (Jk Antigen) is a Glycoprotein on RBC surface involved in urea transport
- Three immunogenic Antigens have been found (Jk-a, Jk-b, Jk-3)
- Rare, but risk of severe Hemolytic Transfusion Reactions and Hemolytic Disease of the Newborn
VII. Types: Other Minor Blood Groups
- MNS (xM, xN)
- Primarily used in paternity cases
- Rarely involved in Transfusion Reactions