To determine if patients sensitized to food remain tolerant after negative food challenge.

We assessed children who had allergic reactions, positive epicutaneous skin test, and/or positive capFEIA to peanut, egg or milk and subsequently had a negative food challenge between 1996 to 2003. Families were contacted by phone and questioned as to the frequency of ingestion of the food(s) in question and if any further reactions had occurred.

There were 302 children <16 years of age with negative food challenges during this period. We randomly reviewed 107 patients (35%) with 121 challenges. 14 (12%) <6 months from challenge were excluded. 28 (23%) were lost to follow-up. Complete data were available for 59 (47%). 40/59 (68%) regularly ate the food with no problem. 4/59 (7%) subsequently reacted, all with egg (4/18; 22%), and all to raw or less well cooked egg; 1/4 completely avoided egg and 3/4 tolerated egg in baked goods. In spite of no reaction, 2/26 previously peanut allergic continued to completely avoid peanut and 10/26 had peanut < weekly. All 15 patients with negative milk challenge tolerated and continued to regularly consume milk.

Subjects with negative egg challenge were more likely to react again than subjects with negative peanut or milk challenge. Peanut allergy remains a concern for many patients, even with a negative challenge. Allergists should consider a second challenge for egg and/or peanut allergic patients.