Lung transplant recipient ended up with a peanut allergy

I have heard of organ transplant recipients experiencing bodily changes, but this story about a woman who received a lung transplant found herself with a new peanut allergy. A peanut allergy is an abnormal, potentially life-threatening immune system reaction to the proteins found in peanuts. 

 Reactions usually occur within minutes to two hours after exposure.

• Skin: Hives, redness, itching, or swelling of the lips, face, and tongue.
• Gastrointestinal: Stomach cramps, nausea, vomiting, or diarrhea.
• Respiratory: Coughing, wheezing, shortness of breath, or throat tightness.
• Cardiovascular: Drop in blood pressure, dizziness, or shock, known as anaphylaxis.

A woman got a lung transplant — and ended up with a peanut allergy, too

LIVESCIENCE, Lauren Schneider Edited by Nicoletta Lanese, Laura Mondragón, eptember 2, 2026

The patient: A 47-year-old woman in Canada

The symptoms: The woman underwent a lung transplant to treat interstitial lung disease, which involves harmful inflammation and scarring of lung tissue. While recovering in the hospital, she ate a bowl of breakfast cereal, which activated a nearly two-hour episode of flushing, itching, shortness of breath and low blood pressure.

This severe, life-threatening allergic reaction is known as anaphylaxis. A report of the woman's case does not mention specific treatment she received for this reaction, but it notes that it resolved after two hours.

What happened next: The woman experienced the same symptoms in the weeks after being discharged from the hospital — after eating a coconut cream pie and after having an almond candy bar.

The diagnosis: Two months after her lung transplant, the woman underwent a skin-prick allergy test, which revealed a sensitivity to peanut and pine nut allergens. She did not have an allergic response to tree nuts, such as the almonds in the candy bar, nor to coconut. None of the foods that triggered her symptoms were known to contain peanuts, but none were certified as peanut-free, either.

Notably, the woman's lung donor had been a 12-year-old boy with a known peanut allergy but no history of anaphylaxis. Her doctors theorized that the transplanted lung tissue contained immune cells from the donor that were sensitized to nut allergens.

The treatment: The woman did not receive a specific treatment to get rid of this new allergic response. However, the sensitivity subsided in follow-up skin-prick tests, and they had disappeared completely by a year after her surgery. She ate peanuts in a supervised setting a few months after the one-year mark and had no reaction. The doctors reasoned that the sensitized immune cells from the donor must have cleared from her body.

What makes the case unique: Only one other case of peanut allergy following a lung transplant had been documented before the woman's case was published in 2011.