Transfusion Reaction Terms & Definitions for Medical Students

Acute Hemolytic Transfusion Reaction (HTR)

Symptoms: rapid onset, fever, pain, hypotension, hemoglobinuria/hemoglobinemia

Major Complications: DIC, Renal Failure, Shock

Causes: Complement Activation

Antibodies: ABO, Rh, Kell

<24 hour onset, intravascular, IgM more often than IgG

Delayed Hemolytic Transfusion Reaction (HTR)

Symptoms: time-delayed onset, fever, unexplained H/H drop, mild jaundice

Major Complications: None

Causes: Anamnestic

Antibodies: Kidd, Duffy, Kell, MNS

>24 hour onset, extravascular, IgG

Febrile Non-Hemolytic Transfusion Reaction (FNHTR)

Symptoms: fever chills, nausea, tachycardia, blood pressure increase

Cause: WBC-derived cytokines in stored product or HLA antibodies in donor components (PLTS)

Allergic Reaction

Symptoms: urticaria, itching, trouble breathing, hives, flushing up to hypotension, anaphylaxis

Causes: allergens and proteins in donor product (IgA antigens in plasma)

Graft vs Host (TA-GVHD)

Symptoms: macopapular rash, fever, diarrhea, multi-organ failure, 90% mortality rate

Causes: recipient does not recognize donor lymphs as foreign. Donor lymphs mount an immune attack on recipient

Transfusion Associated Lung Injury (TRALI)

Symptoms: severe respiratory distress, severe hypoxia/p-edema, fever, hypotension

Causes: donor WBC antibodies (HLA) reactive against recipient WBCs, recipient "primed" WBCs activated by biologically active substances in transfused blood products

Transfusion Associated Circulatory Overload (TACO)

Symptoms: dyspnea, coughing, hypertension, tachycardia

Causes: volume infusion that cannot be effectively processed by recipient, high rates & volumes of infusion, underlying cardiopulmonary pathology

Sepsis

Symptoms: body temp more than 2 degrees above normal, rigors + hypotension

Causes: bacterially-contaminated product transfused

Iron Overload (Hemosiderosis)

Symptoms: yellow tinge to the skin, multi-organ failure

Causes: accumulation of iron in tissues

Citrate Toxicity

Symptoms: paresthesias (tingling/prickling sensation), hypotension, cardiac arrhythmia, tetany, coagulopathy

Causes: inability of liver to metabolize the quantity of anticoagulant infused

At risk patients for this:

- those with liver dysfunction and/or renal disease

- neonates

- hypothermic patients

- PLT & FFP recipients

Post Transfusion Purpura

Symptoms: profound thrombocytopenia, bleeding, petechiae

Causes: patient has a platelet antibody - usually Anti-hpa1

Reportable Transfusion Reactions to the FDA

- where manufacturing, including donor selection, may have been the cause

- sepsis

- TRALI

- hemolytic

Transfusion Reactions not reported to the FDA

- delayed hemolytic transfusion reaction

- most allergic reactions (urticaria, etc)

- febrile non-hemolytic

- circulatory overload