1. Blood Groups/Types

2. Blood Group Terms
Antigens: chemical structures imparting specific properties to the surface of the RBC
Antibodies: protein substance developed in response to foreign body substances ( bind to Antigen)

3. Blood Group Systems
Detected on the basis of specific reaction with corresponding antibody
Presence or absence of the blood protein antigens on the RBC surface
Inherited according to Mendelian( law of genetics)
Fully formed either at birth or in early postnatal life & persist throughout life

4. ABO System Discovered by Landsteiner in 1900
Prior to discovery, blood transfusions were hit or miss
Type A, Type B, Type AB, & Type O

5. Type A 41% of population Has A antigens on the RBC surface
Has anti-B antibodies in the plasma which bind with antigen A causing reaction
Genotypes ( genetic makeup ) AA & AO
Phenotype ( Characteristic) will be A

6. Type B 10% of population Has B antigens on the RBC surface
Has anti-A antibodies in the plasma
Genotype BB & BO = Phenotype B

7. Type AB 4 % of population Has A & B antigens on the RBC surface
Has NO antibodies in the plasma
Universal Recipient: can receive Type A, Type B, Type AB, or Type O blood  NO antibodies in plasma to react with antigens
Genotypes: AB = Phenotype AB

8. Type O 45% of population Has NO antigens on RBC surface
Has anti-A & anti-B antibodies in the plasma
Universal Donor: can be given to any blood type  no antigens on the RBCs
Genotype OO = Phenotype O

9. Rh System Discovered by Landsteiner & Wiener in 1937
Discovered in the Rhesus monkey
Rh is an antigen on the RBC surface

10. Rh + has the antigens on the RBC (85% of population)
Rh – does NOT have the Rh antigens
Rh + can accept Rh + or Rh – blood
Rh – can accept ONLY Rh - blood

11. Rh Incompatibility
When Rh– person receives Rh+ blood in a transfusion  person develops antibodies against the Rh+ factor
Clinical problem if second transfusion of Rh+ blood given  Rh antibodies will clump with the Rh antigens
S & S of transfusion reaction: chills, fever, rash, itching, SOB, nausea, nephralgia, hematuria, shock & death

12. Erythroblastosis fetalis
Rh– mother and Rh+ father  Rh+ child 1st pregnancy
Mother develops antibodies to baby’s Rh+ antigens
2nd pregnancy with Rh+ child  mother’s anti-Rh antibodies attack unborn child’s RBCs
Prevention: shot of Rhogam shortly after birth of first Rh+ baby to block development of antibodies

13. Erythroblastosis fetalis
Antigen-antibody reaction due to mixing of Rh+ blood of fetus with Rh- blood of mother during 2nd Rh+ pregnancy
Prevented with shot of Rhogam at birth of 1st Rh+ baby