BLOOD TRANSFUSION CLINICAL PRACTICE MANUAL

ABO and Rh Blood Group Systems / Compatibility Table Page 1 of 6

ABO Blood Group System ...... 1

Rh (Rhesus) Blood Group System………….………………………………………….………………….. 2

Compatibility …………………………………………………………………………………………………. 3

ABO and Rh Compatibility Table ……………………………………………………………………….…. 4

Clinically Significant Blood Antibodies ………………………………………………………...………..… 5

ABO Blood Group System

In the ABO blood group system, antigens A and B are either present or absent on the exterior of a person’s red blood cells (genetically determined).

The name of an individual’s blood group corresponds to the antigen that is present on the exterior of his/her red blood cells.

Antibodies are found in a person’s plasma. At approximately age 4 months, ABO antibodies have been naturally acquired to the antigen(s) that are absent from the exterior of the individual’s red blood cells.

If the antigen (A or B) is absent from the exterior of a person’s red blood cells, the corresponding antibody will be found in the person’s plasma. If the antigen (A or B) is present on the exterior of a person’s red blood cells, corresponding antibody will not be found in the person’s plasma.

Blood Group Antigen Antibody found on exterior of red blood cell found in plasma Group A A Anti-B Group B B Anti-A Group AB A and B none Group O none Anti-A and Anti-B

ABO Blood Group System in Pictorial Format Legend: Antigen: found on exterior of red blood cell

Antibody: found in plasma

Date effective: Jan 2005 Date revised: August 2019 This is a controlled document. Any copies appearing in paper form must be checked against the electronic version prior to use. This resource has been created specifically for LHSC/SJHC and may not be applicable for other centres. These documents are the intellectual property of LHSC/SJHC. They are not to be shared or duplicated without permission BLOOD TRANSFUSION CLINICAL PRACTICE MANUAL

ABO and Rh Blood Group Systems / Compatibility Table Page 2 of 6

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Rh (Rhesus) Blood Group System

Rh refers to the D antigen. Rh positive individuals have the D antigen present on the exterior of their red blood cells whereas for Rh negative individuals the D antigen is absent on the exterior of their red blood cells (genetically determined).

Unlike the ABO system in the Rh system, if the D antigen is absent on the exterior of the red blood cells the anti-D antibody will only be produced if the individual is exposed to Rh positive red blood cells. This exposure can take place via transfusion of Rh positive red blood cells or platelets (platelets may contain a small amount of red blood cells) or with pregnancy.

To prevent production of the Rh antibody and possible Hemolytic Disease of the Fetus and Newborn in a future pregnancy, Rh negative females of childbearing age (defined as less than 45 years of age) should not be exposed to Rh positive red blood cells. (Refer to Rh Immune Globulin for additional information).

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Date effective: Jan 2005 Date revised: August 2019 This is a controlled document. Any copies appearing in paper form must be checked against the electronic version prior to use. This resource has been created specifically for LHSC/SJHC and may not be applicable for other centres. These documents are the intellectual property of LHSC/SJHC. They are not to be shared or duplicated without permission BLOOD TRANSFUSION CLINICAL PRACTICE MANUAL

ABO and Rh Blood Group Systems / Compatibility Table Page 3 of 6

Compatibility

Patients must be transfused blood products that are ABO compatible (identical is not mandatory) with their blood group. If a patient receives ABO incompatible blood products a hemolytic transfusion reaction can occur (with a potentially fatal outcome).

Compatibility is determined by the antigens and antibodies in the recipient (patient) and the donated (transfused) blood.

A recipient’s (patient’s) plasma antibodies will hemolyze donated (transfused) red blood cells that have the corresponding antigen on their exterior. Example: Group O patient (has anti-A and anti-B antibodies in their plasma) will hemolyze PRBCs transfused if they are given group A, B or AB red blood cells (have antigens A, B and AB respectively).

Donor antibodies in plasma blood products (and infrequently IVIG) can hemolyze the recipient’s (patient’s) red blood cells if the patient has the corresponding antigen on the exterior of their red blood cells. Example: Group AB patient (has antigens A and B on the exterior of their red blood cells) will have hemolysis of their red blood cells if transfused plasma group A, B, or O (have antibodies anti-A, anti-B and anti-A and anti-B respectively).

Date effective: Jan 2005 Date revised: August 2019 This is a controlled document. Any copies appearing in paper form must be checked against the electronic version prior to use. This resource has been created specifically for LHSC/SJHC and may not be applicable for other centres. These documents are the intellectual property of LHSC/SJHC. They are not to be shared or duplicated without permission BLOOD TRANSFUSION CLINICAL PRACTICE MANUAL

ABO and Rh Blood Group Systems / Compatibility Table Page 4 of 6

ABO and Rh Compatibility Table

Patient’s Red Blood Plasma2 Platelets3 Cryoprecipitate2 1 (listed in order of Group Cells preference) O Positive O+, O- All groups O, B, A, AB O Negative O-

A Positive A+, A-, O+, O- A, AB A, AB, B*, O* A Negative A-, O-

B Positive B+, B-, O+, O- Any group is B, AB B, AB, A*, O* B Negative B-, O- safe to Transfuse. AB Positive All groups Only AB AB, B*, A*, O* AB Negative AB-, B-, A-, O-

O+ All males, UNKNOWN Females>45yrs Only AB Any group O- Females<45yrs

Rh Comments 1 Rh Positive PRBC will only be given to an Rh Negative patient when Rh negative PRBC are not available.

2 Rh is not taken into consideration when transfusing plasma or cryoprecipitate

3 If Rh Positive platelets are issued to Rh Negative female patient <45 years of age, RhIg is recommended.

Platelet Comments ABO identical platelets are preferred, however platelet supply limits availability. If ABO identical platelets cannot be issued, the order of preference for non ABO identical platelets is listed for each blood group.

* The plasma in these platelets is ABO incompatible with patient’s group.

Children 12 years of age and under receiving non-ABO identical platelets will have some of the plasma removed (volume reduced) before the platelet is issued from Transfusion Medicine

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Date effective: Jan 2005 Date revised: August 2019 This is a controlled document. Any copies appearing in paper form must be checked against the electronic version prior to use. This resource has been created specifically for LHSC/SJHC and may not be applicable for other centres. These documents are the intellectual property of LHSC/SJHC. They are not to be shared or duplicated without permission BLOOD TRANSFUSION CLINICAL PRACTICE MANUAL

ABO and Rh Blood Group Systems / Compatibility Table Page 5 of 6

Clinically Significant Blood Antibodies

In addition to A and B antigens, human red blood cells have many other antigens (on their exterior) against which antibodies can be formed.

Antibodies formed against the antigens above are clinically significant (can cause hemolysis of red blood cells, like anti-A and anti-B antibodies).

The antibody screen testing (“screen” part of Group and Screen test) is designed to detect antibodies to red cell antigens D, E, C, e, c, K, k, JkA, JkB, FyA, FyB,S,s.

If a patient has any of these antibodies {e.g. anti-D, anti-c}, PRBC units issued from TM will be marked with a red dot indicating those RBCs do not have the corresponding antigen(s) {e.g. D -, c -}.

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Date effective: Jan 2005 Date revised: August 2019 This is a controlled document. Any copies appearing in paper form must be checked against the electronic version prior to use. This resource has been created specifically for LHSC/SJHC and may not be applicable for other centres. These documents are the intellectual property of LHSC/SJHC. They are not to be shared or duplicated without permission BLOOD TRANSFUSION CLINICAL PRACTICE MANUAL

ABO and Rh Blood Group Systems / Compatibility Table Page 6 of 6

Antibodies formed against antigens M, N, LeA and LeB are usually not clinically significant.

If a patient has anti-M, anti-N, anti-LeA, or anti-LeB and their antibody screen testing is positive (i.e. the antibody is reacting), TM does a full crossmatch (i.e. the PRBC unit issued is compatible) but the unit may not be marked with a red dot (phenotyped units are not necessarily required).

Refer to Laboratory Tests for Transfusion: Orders and Results for more information.

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Date effective: Jan 2005 Date revised: August 2019 This is a controlled document. Any copies appearing in paper form must be checked against the electronic version prior to use. This resource has been created specifically for LHSC/SJHC and may not be applicable for other centres. These documents are the intellectual property of LHSC/SJHC. They are not to be shared or duplicated without permission