Transfusion Reactions

Question 1

Acute Hemolytic Transfusion Reaction

Answer 1

• Type II hypersensitivity reaction
• Antibodies present in the recipient recognize antigens on transfused RBCs

– ABO incompatibility results in most severe reactions

– Non-ABO alloantibodies may also cause fatal reactions

• Only a small volume (<10 mL) may be required to initiate reaction

Question 2

Acute Hemolytic Transfusion Reaction Symptoms

Answer 2

• Fever
• Hypotension
• Tachycardia
• Tachypnea
• Renal failure
• Flank pain
• Nausea/vomiting/diarrhea
• Hemoglobinuria (intravascular)
• Jaundice (extravascular)
• Shock
• DIC

Question 3

Febrile NonHemolytic Transfusion Reaction

Answer 3

• Common
• Type II hypersensitivity reaction: recipient has IgG antibodies against donor WBCs and HLA antigens (antibody-antigen reaction results in release of pyrogens)
• WBCs elaborate cytokines during blood product storage
• Symptoms: fever, chills, possibly headache/anxiety/GI upset
• Prevention: Pre-storage leukoreduction of blood products

Question 4

Allergic Transfusion Reaction

Answer 4

• Common
• Type I hypersensitivity reaction: recipient has antibodies against plasma proteins
• Rare cases of anaphylaxis have been due to anti-IgA antibodies in IgA-deficient patients
• Symptoms: urticaria, pruritus, wheezing, localized angioedema
• Anaphylaxis occurs when hypotension, shock, or respiratory arrest also occur

Question 5

Transfusion-Related Acute Lung Injury (TRALI)

Answer 5

• A leading cause of transfusion-related mortality
• Donor anti-HLA or anti-HNA antibodies bind to cognate antigens on recipient leukocytes, causing non-cardiogenic pulmonary endothelial leakage
• Symptoms: acute respiratory distress, fever, hypotension, and new bilateral pulmonary infiltrates
• Diagnosis of exclusion; must rule out other direct and indirect causes of acute lung injury

Question 6

Transfusion-Associated Circulatory Overload (TACO)

Answer 6

• A leading but under-recognized cause of transfusionrelated mortality
• Transfusion of blood products in a patient with decreased blood vessel compliance, cardiac insufficiency, severe COPD, renal insufficiency, and/or lots of other fluids
• Volume overload leads to acute pulmonary edema
• Symptoms: acute respiratory distress, systolic hypertension, peripheral edema, pulmonary infiltrates
• Responds to diuresis

Question 7

Answer 7

Question 8

Hemolytic Disease of the Fetus and Newborn (HDFN)

Answer 8

• Also known as erythroblastosis fetalis
• Group of disorders that result in progressive anemia (with or without edema) and hyperbilirubinemia of the fetus or newborn
• ABO antibodies and alloantibodies against more than 50 non-ABO blood group antigens have been implicated
• Other non-immune causes of HDFN exist: RBC membrane disorders, RBC enzyme defects, and hemoglobinopathies

Question 9

ABO HDFN

Answer 9

• Most commonly in group O mothers with naturally-occurring anti-A and/or anti-B antibodies
• IgG antibodies can cross the placenta
• May occur in the first pregnancy
• Anemia/jaundice are usually mild and rarely require intervention

– A and B antigens are not fully expressed on neonatal RBCs

– Soluble A and B substances in newborn’s plasma can also neutralize the antibodies

– Treatment, if needed, generally consists of phototherapy

Question 10

Non-ABO HDFN

Answer 10

• Mechanism: maternal sensitization from exposure to non-self RBC antigens during prior pregnancy/delivery and/or transfusions
• Rarely affects first pregnancies
• Most clinically significant HDFN cases caused by Rh, Kell, Duffy, Kidd, and MNS antibodies
• Variable severity; may present as jaundice shortly after birth, kernicterus, or hydrops fetalis (abnormal accumulation of fluid in two or more fetal compartments)
• Treatment options may include intrauterine transfusion, phototherapy, or exchange transfusion

Question 11

Rh Immune Globulin

Answer 11