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Hypersensitivity transfusion reaction
Dr Rita So
updated August 2006
Classification
- Confusing among literature
Etiology : Anaphylactic versus Urticarial (anaphylactoid
being a more severe form of urticarial reaction)
Clinical significance which makes
management different : IgA deficiency -related vs Non IgA deficiency-related
Anaphylactic reaction
-
Immune-mediated
-
Most often in patients with a
hereditary immunoglobulin A (IgA) deficiency
-
Some of these patients have
developed complement-binding anti-IgA antibodies that cause anaphylaxis when
exposed to donor IgA
-
Rarely, initiate by transfused IgE
antibodies from the donor
Frequently seen with infusion of
plasma (fresh, fresh frozen or frozen) and cryosupernatant
Not been documented with infusion of
cryoprecipitate
-
In Prince of Wales Hospital, Hong
Kong: Can check Ig pattern for IgA
level but the test for anti-IgA antibody is not available in HK
-
Incidence
About 1 in 700 in the general
population is immunoglobulin (IgA) deficient
However, anaphylactic and
anaphylactoid reactions occur at much lower rates - real anaphylaxis 1 in
~20,000 transfused units
-
Very fast, spectacular illness (only
rarely occur insidiously) – within 1 to 45 minutes
-
Symptoms usually occur with less
than 10 mL of blood transfused
-
Chills
-
Abdominal cramps
-
Dyspnea
-
Vomiting
-
Diarrhea
-
Signs
Urticarial reaction
Also known as minor allergic
reaction
The exact mechanism of this reaction
is uncertain
-
Likely due to cytokines, plasma
protein or other products which activate the same inflammatory and
vasoactive mediators. Allergens in the donor blood include antibiotics or
chemicals used in blood preparation, albumin and C4.
-
Incidence: 1-2%
-
More frequently with components
containing large amounts of plasma, such as whole blood, pooled platelets,
and fresh frozen plasma
-
Urticaria during or 1 hour post
transfusion - occasional severe anaphylactoid reactions especially with
rapid infusion rates
-
Not consistently recur with repeated
transfusions
Management of hypersensitivity reactions
-
Stop the transfusion
-
Support the patient with IV fluid,
100% oxygen; intubate the patient if necessary
-
For mild reactions, administration
of antihistamines (chlorpheniramine 10-20mg iv) and corticosteroids will
rapidly alleviate the clinical signs
-
More severe signs require intensive
shock therapy, including administration of epinephrine 0.5-1mg im
Should one continue with transfusion?
-
For urticarial reaction
Transfusion may proceed normally if
no further progression of symptoms and signs after 30 minutes
Transfusion may need to be
discontinued if antihistamine does not alleviate the symptoms, or severe
persistent urticaria is associated with bronchospasm
-
For anaphylactic or anaphylactoid
reaction
If urgently require further
transfusion
Careful (may consider bedside
leukoreduction filter for reduction of anaphylactoid reaction), controlled,
and monitored transfusion with standard blood components
Transfusions of washed red blood
cells (RBCs) or platelet (PLT) components
Blood components from known IgA
deficient donor
-
Reduce transfusions
-
Selection of components (i.e. use
cryoprecipitate instead of plasma when indicated)
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Pretreatment with antihistamine +/-
steroid
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Slow infusion rates
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For IgA-deficient patients
-
IgA deficient blood components
-
IgA deficient donor (not available in
HK)
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Washed RBC and platelets
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