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

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. ( Treatment for anaphylaxis involves epinephrine (also called adrenaline), and it can also require antihistamines, cortisone, oxygen and beta-agonists, such as albuterol, which help improve breathing.) 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.