Transfusion Medicine For The Pathologist

Front 1

What is the definition of febrile nonhemolytic transfusion reaction?

Back 1

A rise in temperature of 1ºC or greater sometimes accompanied by chills or rigors.
Hemolytic transfusion reaction and bacterial contamination must be excluded.

Front 2

What are the features of febrile nonhemolytic transfusion reaction?

Back 2

Typically occurs during transfusion but can be delayed up to an hour after transfusion.
The fever is usually self-limited and resolves within 2-3 hours, but acetaminophen can be given.

Front 3

How are febrile nonhemolytic transfusion reactions treated?

Back 3

Some people will choose to pretreat with antipyretics.
Some people believe that transfusion should be restarted once the transfusion reaction testing is done so that the patient is exposed to as little donors as possible.

Front 4

What has decreased the incidence of febrile transfusion reactions?

Back 4

Universal leukocyte reduction

Front 5

What has been attributed to the formation of febrile nonhemolytic transfusion reactions?

Back 5

The accumulation of pyrogenic cytokines in units during storage.
Leukocyte reduction at the time of donation has been found to reduce the generation of these cytokines by leukocytes.
Accumulated cytokines can be removed by plasma reduction or washing of the component.

Front 6

What clinical sequelae are associated with allergic transfusion reactions?

Back 6

Pruritus, urticaria, erythema, and cutaneous flushing.
GI involvement includes nausea, vomiting, pain, and diarrhea.

Front 7

How are allergic transfusion reactions treated?

Back 7

Should intubate if there is upper airway involvement or give oxygen if there is dyspnea.
Responds to administration of 50-100 mg diphenhydramine. Can premedicate with 25-50 mg of diphenhydramine before the transfusion.
Transfusion can usually be restarted after treatment without a recurrence.

Front 8

What clinical sequelae are associated with severe allergic (anaphylactic) transfusion reactions?

Back 8

Cardiovascular instability (hypotension, tachycardia, cardiac arrhythmia, shock, cardiac arrest) and respiratory involvement (dyspnea, stridor).

Front 9

How are severe allergic (anaphylactic) transfusion reactions treated?

Back 9

transfusion should be stopped and the IV access maintained.
Epinephrine should be available. Subcutaneous epinephrine (0.3-0.5 mL of a 1:1000 solution every 20-30 minutes or 5 mL of a 1:10000 solution IV every 5-10 minutes) should be given for significant bronchospasm or unresponsive hypotension.

Front 10

Which patients are more prone to allergic (anaphylactic) transfusion reactions?

Back 10

Patients with IgA deficiency can develop anti-IgA and have anaphylactic reactions.
Patients with haptoglobin deficiency can have anaphylactic reactions due to IgG or IgE antihaptoglobin (common in Japanese patients with anaphylactic reactions).