Blood Groups/Types

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)

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

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

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

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

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

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

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

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

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

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

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