Background: Peanut allergy creates great fear in many families because it i
s one of the leading causes of fatal and near-fatal food-induced allergies.
' Earlier reports suggested that peanut allergy was life-long, but a recent
study described resolution of peanut allergy in some children.
Objective: Tolerance to peanut allergy in childhood was studied. Examinatio
n of the natural history of childhood peanut allergy was explored.
Methods: A retrospective review of all children with peanut allergy seen at
the Children's Hospital of Philadelphia in a 3-year period (n = 293). Chil
dren with histories of peanut allergy were challenged at the mean age [3.8
years; range 1.5 to 8 year] which was 1.8 years [range: 0.5 to 6.8 years],
following their last known clinical reaction. Food allergy or tolerance was
confirmed by open challenges.
Results: Thirty-three patients with histories of peanut allergy and a posit
ive skin test to peanut underwent oral challenges. Not one patient (n = 5)
with a history of peanut anaphylaxis developed tolerance to peanuts. In com
parison, 9 of 17 patients with history of urticaria upon ingestion to peanu
ts developed tolerance. Also, 4 of 10 patients with flaring of their atopic
dermatitis upon ingestion to peanuts developed tolerance. The 14 patients
with a negative challenge to peanut had a significantly smaller wheal and f
lare reaction than the 19 patients with positive challenges. Tolerance to p
eanut was documented by a positive challenge reverting to a negative challe
nge in one patient. Oral challenge of 13 additional patients with positive
skin tests and histories of only refusing to eat peanut resulted in 5 (39%)
positive challenges.
Conclusion: A selected group of peanut-allergic children, who do not have a
history anaphylaxis to peanut, may develop tolerance to peanuts.