RESOLUTION OF PEANUT ALLERGY - CASE-CONTROL STUDY

Objectives: To determine whether there are any differences between chi ldren who remain mildly or moderately allergic to peanut and children with similar histories but a negative reaction on challenge with peanu t Design: Case-controls matched for age and sex. Setting: Children's d ay wards in two teaching hospitals. Intervention: Open food challenge with peanut. Subjects: 15 children with resolved peanut allergy (resol vers) and 15 with persistent allergy (persisters). Main outcome measur e: Reaction on challenge with peanut, serum total and peanut specific IgE concentrations. Results: The groups had a similar median age at fi rst reaction to peanut (11 months, range 5-38) and similar symptoms. A llergy to other foods was less common in resolvers (2/15) than persist ers (9/15) (P = 0.02). On skin prick testing with peanut all 13 resolv ers tested but only 3/14 persisters had a weal of < 6 mm CP < 0.0001). Total and peanut specific IgE concentrations did not differ much betw een the groups. Conclusion: Appropriately trained clinicians must be p repared to challenge preschool children with peanut as some will be to lerant despite a history of reactions to peanut and a positive skin pr ick test with peanut Preschool children whose apparent peanut allergy is refuted by food challenge show allergy to other foods less often th an those in whom peanut allergy persists. The size of weal on skin pri ck testing to peanut predicts reactivity but not severity on peanut ch allenge.