Blood groups

Blood Types

Assist. Prof.Dr. Sajeda Al-Chalabi


Blood Types… There are four different types of blood A, B, AB, O They are determined by the antigen found on the RBC Type A, has antigen A on the RBC Type B, has antigen B on the RBC Type AB, has both antigen A and B on the RBC Type O, has neither antigen on the RBC

Blood groups

Type A would have B agglutinins (antibody) in the plasma. Type B would have A agglutinins (antibody) in the plasma. Type AB would not have agglutinins (antibody) in the plasma. Type O would have A and B agglutinins (antibody) in the plasma.

Major ABO Blood Group

Forward blood grouping using anti-sera and red blood cells
ABO Group
Antigen Present
Antigen Missing
Antibody Present
A
A
B
Anti-B
B
B
A
Anti-A
O
None
A and B
Anti-A&B
AB
A and B
None
None
If an antigen (Ag) is present on a patients red blood cells the corresponding antibody (Ab) will NOT be present in the patients plasma, under ‘normal conditions’.


Blood groups
Type O is the universal donor, since it does not have antigens on the surface of the RBC’s.Type AB is the universal recipient, since it does not have agglutinins (antibody) in its plasma.

Average Percents… Type O—45%Type A—40%Type B—11%Type AB—4%

Rh positive or negative
Based on whether it has a antigen D Rh+ has the antigen, Rh- does not have the antigen.

Pregnancy and blood type

Father is Rh+ bloodMother is Rh– Child could be Rh +.1st pregnancy--if the baby is Rh +, then there are no complications. However, the mother will start to develop antibodies against the Rh factor

Pregnancy

Second pregnancy, if the child is +, the mother’s antibodies can cross the placenta and start to attack the fetus’ blood cells, causing hemolysis.Hemolysis--breakdown of RBC and the release of hemoglobin into the plasma which can damage organs.This is called erythroblastosis fetalis,can cause severe anemia, jaundice possibly death.

Procedure:

Use WBC pipette

Suck blood to 0.5 and dilute it with normal saline (0.9% NaCl) to 11 Shack for 10 seconds Get rid of the first 4 drops Put on the slid one drop of anti A, anti B , anti D ( keep a good space between each other Add drop of the diluted blood on each anti Mix with an applicator stick and wait for about 2 minutes Examine by eye and by microscope

Blood type

Anti A
Anti B
Anti D
Anti D
A
+
-
+
A+
-
A-
B
-
+
+
B+
-
B-
AB
+
+
+
AB+
-
AB-
o
-
-
+
O+
-
O-

Cross match

We do blood typing & cross matching before blood transfusion. Blood from the donor (contains antigen) to be mixed with the serum from the recipient who has the same blood group (contain antibodies). If any reaction (agglutination) occurs , the blood considered to be incompatible If no agglutination , the blood is compatible.