Food Allergy and Atopic Eczema Professor Gideon Lack Kings College - - PowerPoint PPT Presentation

Food Allergy and Atopic Eczema

Professor Gideon Lack King’s College London

Relationship between Food Allergy & Atopic Dermatitis

Food allergy

Atopic dermatitis

Atopic dermatitis

Food allergy

Atopic dermatitis

Food allergy

Prevalence of AD in FA

91.3 88.1 42 10 20 30 40 50 60 70 80 90 100 Peanut Allergic Egg Allergic Unselected % with eczema

p<0.001 p<0.001

Prevalence of food allergy* and atopic dermatitis

Sampson

1985

56%

Sampson

1995

73%

Eigenmann (Baltimore)

1998

37%

Eigenmann (Geneva)

2000

27%

Niggemann

1999

81%

Roehr

2001

55%

* Proven by DBPCFC

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
• nset (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. 2008 Jan;38(1):161-8.

Does food allergy cause atopic dermatitis?

Oral Provocation Studies Interventional Studies

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: 1053-1058

106 challenges in 64 patients 49 Negative challenges 57 Positive challenges

DBPCFC to milk, egg, wheat and soy in children median age 2 years with AD and suspected FA

56.5% Delayed eczematous Lesions* 43.5% Immediate reactions

• nly

12% Delayed eczematous lesions only

45% Delayed eczematous lesions after immediate symptoms

Delayed = >24hrs *Mean increase in SCORAD 14.2, p<0.001

Breuer K. Clin Exp Allergy 2004; 34: 817-24.

Causes of late eczematous reactions

Milk 28% Egg 27% Soya 9% Wheat 21% Other 15%

Breuer K. Clin Exp Allergy 2004; 34: 817-24.

Does food allergy cause atopic dermatitis?

Oral Provocation Studies Interventional Studies

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.

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.

Relationship between Food Allergy & Atopic Dermatitis

Food allergy

Atopic dermatitis

Atopic dermatitis

Food allergy

Atopic dermatitis

Food allergy

Cutaneous Route

IgE “Allergy”

Saloga et al. Am J Respir Crit Care Med 1994; 149: 65-70 Strid et al. Eur J Immunol 2004; 34: 2100-9

PEANUT TOLERANT (NA) PEANUT ALLERGY (PA)

Route of peanut exposure

Cutaneous exposure Oral exposure

CLA + T cells α4β7+ T cells Chan et al. Allergy. In Press.

0% 20% 40% 60% 80% 100% 1 2 3 4 5 6 7 8 9 10 Peanut Allergic P ercen tag e o f to tal p ro liferatio n (% ) CLA% B7% 0% 20% 40% 60% 80% 100% 1 2 3 4 5 6 7 8 9 10 Peanut Non Allergic P ercentage of total proliferation(% ) CLA% B7%

CLA+ and α4β7+ proliferation as a percentage of total CLA+ and α4β7+ proliferation to 400g/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.

Peanut allergy is associated with:

Lack G et al. NEJM 2003; 348: 977-985

Eczema:

OR = 2.6, 95%CI 1.4 - 5.0

Oozing crusted rash:

OR = 5.2, 95%CI 2.7 - 10.2

Topical Arachis oil:

OR = 6.8 , 95%CI 1.4-32.9

n=97

.2 .4 .6 .8 1 Proportion peanut-allergic 50 100 150 Average total household peanut consumption during 1st yea

n=286

Fox AT et al. J Allergy Clin Immunol 2009; 123: 417-23.

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

p=0.01 7 p=0.06 8 2.3

Bed-sheet

(mcg/m 2)

Pillow-case

(mcg/m 2)

Household peanut consumption and infant environmental peanut exposure

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 2.8-10.2) I UK and Canada even after controlling for coexistent eczema (p=0.0008)

Sandilands A et al. Nature Genetics 2007;(5):650-4. Brown SJ et al. JACI 2011; 127(3-4): 661–667

Adapted from Irvine AD et al. N Engl J Med 2011;365:1315-27 Normal Patient Filaggrin Deficient Patient

Adapted from Irvine AD et al. N Engl J Med 2011;365:1315-27

Summary

Food allergy

Atopic dermatitis

Atopic dermatitis

Food allergy

Atopic dermatitis

Food allergy