Researchers of RUNMC have described the development of a severe allergic reaction after a blood transfusion

Researchers of RUNMC have described the development of a severe allergic reaction after a blood transfusion

Researchers at the Department of Laboratory Medicine, RUNMC have described in a recent edition of NEJM the development of a severe allergic reaction after a blood transfusion. They have strong evidence that peanut allergens in the blood transfusion provoked a reaction in a patient with a peanut allergy.

It is known that when an allergic donor gives blood, the recipient might also, temporarily, take over the allergy. How this goes in the opposite situation was unknown. For example, what might happen when a patient who is allergic to peanuts receives blood from a donor who has eaten peanuts the night before?

Our research shows that although many properties of the peanut are destroyed by the gastric acid, a part of the peanut protein ("allergen") survives and enters the donor's bloodstream.

We describe a 6 years old patient who experienced a severe allergic reaction during a platelet transfusion. The donors were found to have eaten peanuts in the evening prior to donation. The patient proved to be allergic, not merely to raw peanuts, but also for the peanut protein in the blood. We believe this to provide strong evidence that, when confronted with apparently inexplicable reactions to transfusion, to allow for the possibility of allergens in the transfusion product, especially in patients with known allergies, In every blood transfusion there is a small risk for a transfusion-reaction, also in non-allergic patients. Clinicians are well aware of this and take pre-cautions to cope with transfusion-reactions. Whether or not our findings will change any of the current protocols surrounding blood donations or special blood products for allergic patients is difficult to tell at this moment. Further research is needed before evidence-based decisions on this point can be taken.

In conclusion, while it is true that every transfusion of blood carries a small risk of a reaction to it, even for patients without an allergy, we must not lose sight of how rare they are. And, furthermore, doctors know how to deal with a reaction should it arise.

Photo: Irma Joosten