A clinical research consortium sponsored by NIAID and JDRF
Sayre P, Broide D, Seyfert-Margolis V, Roberts G, Du Toit G, Turcanu V, Fisher HR, Nirenstein L, Radulovic S, Stephens A, Nasser N, Murphy S, The Immune Tolerance Network ITN032AD Study Group, Lack G
University of Southampton, Southampton, UNITED KINGDOM King’s College London, London, UNITED KINGDOM Immune Tolerance Network, UCSF, San Francisco, CA University of California, San Diego, San Diego, CA Biostatistics, Rho, Inc, Chapel Hill, NC.
Rationale: To assess the rate of sensitisation to food allergens in infants in the LEAP study.
Methods: The LEAP study is a randomised control study designed to determine whether early introduction of peanuts prevents peanut allergy. Infants aged 4-11 months, at high risk for peanut allergy because of severe eczema and/or egg allergy were recruited. As part of the baseline assessment, all were tested for a panel of food serum IgEs (Pharmacia, Uppsula, Sweden). Sensitization was defined as ³0.35kU/L and pattern of co-sensitisation were explored using Spearman's correlation coefficients.
Results: 640 infants were enrolled. Their median age was 7.8 months (range 4-11), 60% male, 98.8% had eczema of which 89.1% of participants met the study criteria for Severe Eczema, 65.31% had Egg Allergy. Rates of sensitization to the foods were: peanut (22.81%), hen's egg white (61.72%), cow's milk (31.25%), sesame (22.19%), brazil nut (15.63%), hazel nut (20.16%), cashew (21.09%), walnut (3.59%) and almond (14.06%). Many were multiply sensitized (1: 26.88%, 2: 15%, 3: 6.72%, 4: 4.69%, >4: 16.25%). Peanut specific IgE was significant correlated to egg white (correlation coefficient 0.43), milk (0.43), sesame (0.51), brazil (0.52), hazel (0.55), cashew (0.52), walnut (0.38) and almond (0.51). Higher levels of correlation (0.81-0.82) were seen between the brazil, hazel and cashew nuts.
Conclusions: Infants with eczema have a high rate of sensitization to food allergens; many are multiply sensitized. High rates of co-sensitization are seen, especially between the tree nuts, reflecting a subject's allergic tendency or homology in B- or T-cell epitopes.
