Can a patient with AB positive blood group receive O group platelets?

Can an AB Positive Patient Receive O Group Platelets?

Yes, an AB positive patient can receive O group platelets, though ABO-compatible platelets are preferred when available to optimize platelet increments and minimize hemolysis risk. 1

ABO Compatibility Principles for Platelet Transfusion

Primary Recommendation

• ABO-compatible products should be provided whenever possible to optimize post-transfusion platelet count increments and minimize the risk of hemolytic reactions. 1
• Transfusing ABO-identical or ABO-compatible platelets is the preferred approach when inventory allows. 1
• Red cell cross-matching is not required for platelet products due to minimal red cell content. 1

When O Platelets Can Be Given to AB Patients

O group platelets can be transfused to AB positive patients, but this represents an ABO-incompatible transfusion (the plasma in O platelets contains anti-A and anti-B antibodies that can react with the recipient's A and B antigens). 1, 2

The key considerations are:

• Most transfusion services (83%) have policies addressing ABO-incompatible platelet transfusions, though specific management approaches vary widely. 2
• ABO incompatibility can compromise post-transfusion platelet count increments, particularly when assessing for platelet refractoriness. 1
• Incompatible plasma from platelet transfusions can cause hemolysis, with children at particularly high risk. 1

Risk Mitigation Strategies

Volume and Titer Considerations

• Anti-A and anti-B titers in group O pooled platelets are comparable to apheresis platelets, with mean titers of 16 and 8 by tube method, and 64 and 32 by gel method. 3
• Some facilities implement volume limits of ABO-incompatible plasma, volume-reduction of incompatible products, or screening for critical titers of anti-A or anti-B (though only 53 of 2623 facilities with policies use titer screening). 2
• Exercise greater caution with ABO-incompatible platelets in children due to higher hemolysis risk from incompatible plasma. 1

Clinical Monitoring

• Acute intravascular hemolysis, though rare, has been documented following transfusion of group O platelets to non-group O recipients, even with low isohemagglutinin titers. 4
• In bone marrow transplant recipients receiving ABO-incompatible platelets, 9 of 11 group A patients developed positive direct antiglobulin tests, though without clinical hemolysis or increased transfusion requirements. 5
• ABO-immune complexes formed from anti-A/anti-B antibodies and soluble antigens can cause increased hemolysis, inhibition of platelet function, and disruption of clot formation kinetics. 6

Critical Clinical Scenarios

Assessing Platelet Refractoriness

• ABO compatibility is essential when evaluating refractoriness. 1
• Refractoriness should only be diagnosed after at least two ABO-compatible transfusions (stored <72 hours) result in poor increments (corrected count increment <5,000 or absolute increment <2,000/unit). 1
• Do not diagnose platelet refractoriness based on ABO-incompatible transfusions. 1

Massive Transfusion in Trauma

• The platelet concentrate transfused must be ABO-identical or at least ABO-compatible to provide good yield in trauma patients requiring massive transfusion. 1

Common Pitfalls to Avoid

• Do not use ABO-incompatible transfusions to assess platelet refractoriness, as poor increments may be due to ABO mismatch rather than alloimmunization. 1
• Be aware that most facilities lack consensus on specific methods to minimize transfusion of anti-A or anti-B when ABO-incompatible platelets must be used. 2
• Monitor for signs of hemolysis (cherry-colored urine, hemoglobin drop) particularly in immunosuppressed, transfusion-dependent patients, and children. 4

Practical Algorithm

1. First choice: Provide AB-compatible platelets (AB or O) to AB positive patients. 1
2. If O platelets must be used: Proceed with transfusion but maintain heightened vigilance for hemolysis, particularly in high-risk populations (children, immunosuppressed). 1, 4
3. Monitor post-transfusion: Assess for signs of hemolysis and document platelet count increments. 1
4. For refractoriness evaluation: Use only ABO-compatible products stored <72 hours. 1