Immunological
Red cells: Immediate or delayed haemolytic transfusion reactions.
Acute Haemolysis
Cause: incompatible red cells, usually in the ABO system,
Mechanism: There is complement activation by Ag-Ab (IgM antibody).
C / P: occurs within minutes
Rigors and fever.
Lumbar pain.
Haemoglobinuria
Chest tightness.
Renal failure.
Hypotension.
Management:
1. Stop the transfusion.
2. Re-check cross matching.
3. Fluid Replacement
4. Alkalinization of urine.
Delayed haemolytic transfusion reactions
Mechanism: The transfusion has stimulated the production of antibodies (IgG) which was
not detected at the initial cross match. Haemolysis is usually extravascular.
C/P: This occurs 5-7 days after transfusion → Anaemia + jaundice
Diagnosis: Antibody detection, spherocytes in blood film.
Treatment:
Compatible blood use.
Leucocytes and platelets:
• Non-haemolytic (febrile) transfusion reactions.
• Post-transfusion purpura.
• Poor survival of transfused platelets and granulocytes.
• Transfusion associated lung injury
Febrile non haemolytic transfusion
reacctions
These reactions are common in patients who have previously been transfused or pregnant, due
to presence of leucocyte antibodies against donor leucocytes, leading to release of pyrogens or
cytokines from donor leucocytes.
C / P: Fever — chills and rigors.
Treatment:
• Stop transfusion Antipyretics.
• Use of leuco-depleted blood.
Plasma proteins: Urticarial and anaphylactic reactions.
Transfusion – related acute lung injury (TRALI
Cause: Potent leucocyte antibodies in the plasma of donors, against recipient leucocytes, may
cause severe pulmonary reactions
C/P: dyspnea, fever, cough,
Investigations: hypoxia. lung shadow in the perihilar and lower lung fields on the x-ray chest,
Treatment: Mechanical ventilation may be required
Non Immunological
• Transmission of infection:
Viruses: HBV, HCV, HIV, CMV, EBV.
Parasites: Malaria – Trypanosomiasis – Toxoplasma.
• Circulatory volume overload.
• Iron overload due to multiple transfusions.
• Massive transfusion of stored blood may cause bleeding reactions e.g (dilutional
coagulation defect) and electrolyte disturbances.
• Thrombophlebitis.
• Air embolism.
