A 10-year-old boy's peanut allergy seems to have disappeared after he received a bone marrow transplant[1] for his leukemia, according to new research.


The boy, whose case was described and presented at the annual meeting of the American College of Allergy, Asthma and Immunology, previously had a severe peanut allergy where he vomited and got hives all over his body in response to eating peanuts. He was known to have this allergy since he was 15 months old.


At age 10, he receive a bone marrow transplant for leukemia from a donor who did not have a peanut allergy. After the transplant, the boy no longer had an allergic reaction to peanuts, which was tested by an oral food challenge (where a person eats a small amount of the food allergen to determine allergy).


"Food allergy is associated with the body's abnormal production of high specific IgE levels," study author Steven Weiss, M.D., Ph.D., a fellow of the ACAAI, said in a statement. This finding suggests "genetic modification during the early stages of immune cell development in bone marrow may play a large role in causing allergy[2] ."


Peanut allergy is the most common kind of food allergy[3] ; milk and shellfish are the second and third most common food allergies, according to the American Academy of Allergy, Asthma and Immunology. About 8 percent of children have a food allergy, and 38.7 percent of those children with food allergies have a very severe reaction.