Patient: A 6 year old boy in the Netherlands
symptoms: The child was being given blood transfusion as a treatment lymphoblastic leukemiaA type of blood cancer that originates in the bone marrow after she experienced a severe allergic reaction. His blood pressure dropped and he developed a rash. Swelling appeared around his lips, tongue and eyelids and he started having difficulty breathing. This type of allergic reaction is known as anaphylaxisMay be life threatening.
what happened next: Doctors treated the patient with hormones epinephrine (also called adrenaline), which rapidly reduces tissue swelling caused by anaphylaxis, as well as increasing blood pressure and reducing breathing difficulties. After about 30 minutes the child became fine.
His doctors collected blood samples soon after the reaction, and these had abnormally high levels of a type of protein. mast-cell tryptaseWhich is released by certain immune cells during anaphylaxis. However, doctors were puzzled as to what was causing such a severe reaction, they wrote in an article case report.
Diagnosis: The patient’s mother told doctors that she had had a similar allergy to peanuts when her child was about 1 year old, and since then, she had eliminated peanuts from his diet. Doctors then contacted the five blood donors who had recently given blood to the boy, and learned that three of the five donors had eaten a handful of peanuts the evening before donating blood.
Peanuts contain a protein called jigsaw h2 It is one of the main allergens that trigger allergic reactions in people’s immune systems. One of the building blocks of the allergen, called DRP-Ara H2, takes more than 24 hours to be digested and during that entire time it is able to bind to receptors and trigger an allergic response.
To see if this allergen might play a role in the patient’s reaction, doctors ran another blood test that detects antibodies And it is used to identify allergic sensitivities. Testing confirmed that the patient was allergic to peanuts and that antibodies against Ara H2 and DRP-Ara H2M were present in his blood after the injection. These antibodies may have been produced in response to Ara H2 entering the bloodstream.
Get the world’s hottest discoveries delivered straight to your inbox.
“These data are consistent with the hypothesis that peanut consumption by donors before blood donation provided the trigger for this patient’s transfusion reaction,” the doctors said.
treatment: The patient did not require any further treatment after epinephrine was immediately administered to reverse the anaphylaxis.
What makes the case unique: Allergic reactions during blood transfusion are rare, although estimates of their exact frequency vary. Some estimates suggest that they occur approximately 0.001% to 0.006% of transfusions, while others find that they occur 0.1% of transfusion.
The triggers that initiate these allergic reactions are rarely identified. Before this case, other researchers had suggested that blood transfusions could Passively transfer food allergies From donor to recipient. Indeed, a growing body of evidence suggests that This may be more common than expected.
The child’s reaction highlights the importance of identifying food allergies in people receiving blood transfusions, the child’s doctors concluded, as well as the need to review the recent dietary history of blood donors to check for potential allergies that could affect sensitive recipients.
“It is possible that allergens transferred to blood products from other patients may have caused reactions that are unexplained and unreported,” the doctors wrote in the case report.
This article is for informational purposes only and is not intended to provide medical advice.
Jacobs, J.F.M., Baumert, J.L., Brons, P.P., Joosten, I., Koppelman, S.J., and Van Pampus, E.C.M. (2011). Anaphylaxis from passive transfer of peanut allergen into a blood product. New England Journal of Medicine, 364(20), 1981-1982. https://doi.org/10.1056/nejmc1101692
Can you guess the diagnosis in these strange medical cases? Find out with us Diagnostic Dilemma Quiz!
Subject