A lung transplant was followed by a temporary peanut allergy

A 47-year-old woman in Canada developed a peanut sensitivity after receiving a lung transplant, in a rare case that doctors believed may have involved immune cells carried in the donated organ. The woman had undergone the transplant to treat interstitial lung disease, a condition involving inflammation and scarring in lung tissue. While recovering in the hospital, she ate a bowl of breakfast cereal and soon experienced flushing, itching, shortness of breath and low blood pressure. The episode lasted nearly two hours and was consistent with anaphylaxis, a severe allergic reaction. Similar symptoms returned after she left the hospital. They occurred after she ate coconut cream pie and later an almond candy bar. None of those foods were known to contain peanuts, although they were not certified peanut-free. Two months after the transplant, a skin-prick test showed sensitivity to peanut and pine nut allergens. The test did not show an allergy to tree nuts, including almonds, or to coconut. The woman’s lung donor was a 12-year-old boy with a known peanut allergy, although he had no history of anaphylaxis. The doctors who reported the case theorized that sensitized immune cells from the donor could have remained in the transplanted lung and triggered the recipient’s reactions. A blood test for peanut-specific antibodies was negative. According to the doctors, that result suggested her body was not continuing to produce the antibodies. They considered the possibility that antibodies already attached to immune cells in the donor tissue, such as mast cells or basophils, had played a role. The report also noted that the skin-prick response could indicate involvement from lymphocytes, another type of immune cell. The new sensitivity gradually faded. Follow-up skin-prick tests showed a decline, and the allergy had disappeared completely by one year after surgery. Several months later, the woman ate peanuts under medical supervision and had no reaction. A case report published in 2011 said only one other instance of peanut allergy after a lung transplant had previously been documented. Donor-acquired allergies have also been reported after other organ transplants, with lung and liver transplants appearing more commonly associated with them than other solid-organ procedures. The case doctors and authors of a later review called for more detailed donor allergy histories and allergy testing after transplantation, which could help identify and manage similar reactions.