Food Allergy and Atopic Eczema. Professor Gideon Lack King s College London

Size: px

Start display at page:

Download "Food Allergy and Atopic Eczema. Professor Gideon Lack King s College London"

James Robertson
7 years ago
Views:

1 Food Allergy and Atopic Eczema Professor Gideon Lack King s College London

2 Relationship between Food Allergy & Atopic Dermatitis Food allergy Atopic dermatitis Atopic dermatitis Food allergy Atopic dermatitis Food allergy

3 Prevalence of AD in FA % with eczema Peanut Allergic Egg Allergic Unselected 42 p<0.001 p<0.001

4 Prevalence of food allergy* and atopic dermatitis Sampson % Sampson % Eigenmann (Baltimore) % Eigenmann (Geneva) % Niggemann % Roehr % * Proven by DBPCFC

Eigenmann (Baltimore) 1998 37% Eigenmann

The relationship between eczema severity and the frequency of high-risk IgE food sensitization (HR-IgE-FS) to foods according to the age of onset of eczema is shown.

5 The relationship between eczema severity and the frequency of high-risk IgE food sensitization (HR-IgE-FS) to foods according to the age of onset of eczema is shown. The children with the most severe eczema (Q4), and the earliest age of onset (3 months), had the greatest frequency of HR-IgE-FS D. J. Hill, C. S. Hosking, F. M. de Benedictis, A. P. Oranje, T. L. Diepgen, V. Bauchau and the EPAAC Study Group. Clin Exp Allergy Jan;38(1):161-8.

The children with the most severe eczema (Q4), and the earliest age of onset (3 months), had the greatest

6 Does food allergy cause atopic dermatitis? Oral Provocation Studies Interventional Studies

7 Oral Provocation Studies 139 children, mean age 13 months Mild AD 59%, Moderate 32%, Severe 9% Suspected food involvement by doctor or parent Niggemann B. J Allergy Clin Immunol 2001; 108:

8 DBPCFC to milk, egg, wheat and soy in children median age 2 years with AD and suspected FA 106 challenges in 64 patients 57 Positive challenges 43.5% Immediate reactions only 56.5% Delayed eczematous Lesions* 49 Negative challenges 45% Delayed eczematous lesions after immediate symptoms 12% Delayed eczematous lesions only Delayed = >24hrs *Mean increase in SCORAD 14.2, p<0.001 Breuer K. Clin Exp Allergy 2004; 34:

5% Delayed eczematous Lesions* 49 Negative challenges 45% Delayed eczematous lesions after immediate

9 Causes of late eczematous reactions Other 15% Milk 28% Wheat 21% Soya 9% Egg 27% Breuer K. Clin Exp Allergy 2004; 34:

10 Does food allergy cause atopic dermatitis? Oral Provocation Studies Interventional Studies

11 Interventional studies: Can Dietary Restriction Improve Atopic Dermatitis? 16 interventional studies to address this No meta-analyses Varying Study populations Intervention Design Outcome measures Fiocchi et al. Allergy 2004; 78: s78-85.

12 Review of Studies 15 of 16 studies report some response, but variable Interventions most effective in infants Successful interventions include egg, milk & wheat avoidance Effect is generally small Fiocchi et al. Allergy 2004; 78: s78-85.

Successful interventions include egg, milk & wheat

13 Relationship between Food Allergy & Atopic Dermatitis Food allergy Atopic dermatitis Atopic dermatitis Food allergy Atopic dermatitis Food allergy

14 Cutaneous Route IgE Allergy Saloga et al. Am J Respir Crit Care Med 1994; 149: Strid et al. Eur J Immunol 2004; 34:

15 Route of peanut exposure Cutaneous exposure α4β7+ T cells PEANUT TOLERANT (NA) PEANUT ALLERGY (PA) CLA + T cells Oral exposure Chan et al. Allergy. In Press.

16 100% 100% P e rc e n ta g e o f to ta l p ro li fe ra tio n (% ) 80% 60% 40% 20% 0% CLA% B7% P ercen tag e o f to tal p ro liferatio n (% ) 80% 60% 40% 20% 0% CLA% B7% Peanut Allergic Peanut Non Allergic CLA+ and α4β7+ proliferation as a percentage of total CLA+ and α4β7+ proliferation to 400µg/ml peanut in each patient on day 5, showing proliferation to peanut predominating in the CLA subset of PA patients and a more mixed response in peanut tolerant (NA) patients. Chan et al. Allergy. In Press.

proliferation as a percentage of total CLA+ and α4β7+ proliferation to 400µg/ml peanut in each patient on day 5, showing proliferation

17 Peanut allergy is associated with: Eczema: OR = 2.6, 95%CI Oozing crusted rash: OR = 5.2, 95%CI Topical Arachis oil: OR = 6.8, 95%CI Lack G et al. NEJM 2003; 348:

2, 95%CI 2.7-10.2 Topical Arachis oil: OR = 6.

18 Proportion of allergic children with peanut allergy as a function of household peanut consumption during infancy, and as a function of maternal peanut consumption during pregnancy Proportion peanut-allergic n=286 n= Average total household peanut consumption during 1st year (g/week) Fox AT et al. J Allergy Clin Immunol 2009; 123:

pregnancy Proportion peanut-allergic 0.2.4.6.

19 Bed-sheet (mcg/m 2 ) Pillow-case (mcg/m 2 ) p= p=

20 Household peanut consumption and infant environmental peanut exposure

21 Filaggrin Filaggrin forms a dense protein lipid matrix regulating permeability of the skin to water and external particles Loss-of-function filaggrin mutations: Common (up to 10%) in Caucasian populations Associated with up to 50% of moderate-severe eczema Associated with peanut allergic (OR 5.3; CI ) I UK and Canada even after controlling for coexistent eczema (p=0.0008) Sandilands A et al. Nature Genetics 2007;(5): Brown SJ et al. JACI 2011; 127(3-4):

22 Normal Patient Filaggrin Deficient Patient Adapted from Irvine AD et al. N Engl J Med 2011;365:

23 Adapted from Irvine AD et al. N Engl J Med 2011;365:

24 Summary Food allergy Atopic dermatitis Atopic dermatitis Food allergy Atopic dermatitis Food allergy

Gestione della dermatite atopica

Gestione della dermatite atopica Peroni Diego Clinica Pediatrica di Verona Pathogenesis of atopic eczema Genes Environment Abnormal TH2 immune response to environmental allergens Skin hyperresponsiveness