Table 8.10-1. Acute transfusion reactions according to the cardinal symptoma

Differential diagnosis


Cause and clinical features



Cardinal symptom: fever 38°C-39°C without associated symptomsc

Febrile nonhemolytic transfusion reaction

1:300 RBCs

1:20 platelet pools

Inflammatory mediators within blood products; fever usually isolated

None required

– Transfusion may be restarted after medical evaluation

– Consider acetaminophen

Cardinal symptom: fever 39°C or with associated symptomsc

Febrile nonhemolytic transfusion reaction

As above

As above

– CBC, electrolytes, creatinine, bilirubin, LDH, haptoglobin, INR, PTT, fibrinogen

– Repeat group and screen, DAT

– Patient blood and blood product cultures

– Urinalysis

– Stop transfusion

– Consider acetaminophen for fever and meperidine for significant rigors

Acute hemolytic transfusion reaction

1:38,000 RBCs

Usually due to ABO incompatible transfusion (secondary to clerical errors), may be due to other alloantibodies; associated with dyspnea, back pain, dark urine, DIC, and renal failure

– Stop transfusion

– Check for clerical errors

– Maintain urine output

– Manage DIC and AKI

Bacterial sepsis

1:10,000 platelet pools

1:250,000 RBCs

Bacterial contamination of blood product; associated with usual symptoms and signs of sepsis

– Stop transfusion

– Start broad-spectrum antibiotics immediately (prior to culture results)

– Supportive care

Cardinal symptom: dyspnea


Likely underestimated; 1:700 to 1:13 recipients

Volume overload; inflammatory mediators likely contributive and blood product volume is not equivalent to crystalloids

– Chest x-ray

– Other tests as for fever and anaphylaxis, depending on additional clinical manifestations

– Stop transfusion

– Diuretics

– Supportive care

– Prevention is key


True incidence unknown; likely 1:10,000-1:100,000

ARDS secondary to transfusion; anti-HLA or anti-HNA antibodies in donor plasma incompatible with recipient; may be associated with hypotension, fever, and transient cytopenias

– Supportive care

– Diuretics usually administered because differentiation with TACO is difficult, but they are not effective

Bacterial contamination

As above


As above


As above


Acute hemolytic transfusion reaction

As above

As above


As above


As below

As below

As below

Cardinal symptom: urticaria (hives), itching, or rash

Minor allergic reaction

1:200 RBCs

1:30 platelets and plasma

Allergens in blood products, usually not identified; urticarial rash (<2/3 of body surface) or other isolated mucocutaneous symptoms

None required

– Transfusion may be restarted after medical evaluation

– Consider antihistamines


Major allergic reaction/anaphylaxis

Rare; true incidence unknown

Allergens in blood products, usually not identified; can be due to anti-IgA antibodies in IgA-deficient individuals; manifests as urticarial rash associated with other allergic symptoms (hypotension, airway obstruction, digestive symptoms)

– Anaphylaxis: IgA and haptoglobin; anti-IgA if IgA-deficient

– Other tests depending on associated symptoms (chest x-ray, blood cultures, hemolysis testing)

– Do not restart transfusion

– Usual management of anaphylaxis: epinephrine, glucocorticoids, antihistamines, supportive care

– IgA-deficient products may be provided if anti-IgA are identified

Cardinal symptom: hypotension

Acute hypotensive reaction


Bradykinin-induced hypotension, most common with ACEI use; isolated hypotension without other symptoms

No specific investigations

– Stop transfusion (resolves with cessation)

– Supportive care

a Main symptom usually associated with the reaction; other symptoms may be present.

b Incidence in Canada.

c Symptoms associated with fever that warrant further investigations include shaking/rigors/chills, hypotension, dyspnea, chest/back pain, tachycardia, nausea, vomiting, and hemoglobinuria.

ACEI, angiotensin-converting enzyme inhibitor; AKI, acute kidney injury; ARDS, acute respiratory distress syndrome; CBC, complete blood count; DAT, direct antiglobulin test; DIC, disseminated intravascular coagulation; HLA, human leukocyte antigen; HNA, human neutrophil antigen; INR, international normalized ratio; LDH, lactate dehydrogenase; PTT, partial thromboplastin time; RBC, red blood cell; TACO, transfusion-associated circulatory overload; TRALI, transfusion-related acute lung injury.