Greg RexDepartment of Pediatrics, Division of Allergy

IWK Health Centre

Immunology and Allergy Update

Faculty/Presenter Disclosure

• Faculty: Gregory Rex, MD, FRCPC

• Relationships with commercial interests:• Speakers Bureau/Honoraria: Takeda, Merck

CFPC CoI Templates: Slide 1

Disclosure of Commercial Support

• None

CFPC CoI Templates: Slide 2

Mitigating Potential Bias

• Today I will discuss topics unrelated to the companies mentioned in the previous slide.

CFPC CoI Templates: Slide 3

Objectives

• Review current recommendations for food/allergen exposure in infancy

• Review recent advances in peanut allergy prevention• Discuss which “at risk” infants would be appropriate for specialist

referral.

Peanut (PN) Allergy

PN allergy prevalence: 1.4% to 3% in Western countries; quadrupled in past 13 yrs

Leading cause of anaphylaxis and death due to food allergy

Significant psychosocial/economic burdens on patients/families

Develops early in life and is not commonly outgrown

“Becoming Allergic – Immunology 101”

• Need exposure to sensitize (placenta, breast milk, infant diet)• ? Immature gut• ? Immature immune system

AAP Guidelines

Based on infant feeding trials

Made “immunologic sense”

Some data fradulent

“Solid foods should not be introduced into the diet of high-risk infants until 6 months of age, with dairy products delayed until 1 year, eggs until 2 years, and peanuts, nuts, and fish until 3 years of age.”

-AAP Statement 2000

“Although solid foods should not be introduced before 4 to 6 months of age, there is no current convincing evidence that delaying their introduction beyond thisperiod has a significant protective effect on the development of atopic disease.”

-AAP Statement 2008

AAP Guidelines

Rates of PN allergy and atopy continued to rise

Data becoming “better” and showing no benefit to delaying introduction

Observational Data

Koplin et al, JACI 2010 2589 children followed and skin tested / challenged

with egg at 1 year; comparing introduction at 4-6 months vs later

Much higher (OR of 3.4) risk of egg allergy with delayed egg introduction

Early consumption of peanuts in infancy is associated with a low prevalence of peanut allergy

Methods 5171 Jewish school children

in UK and 5615 Jewish school children in Israel were compared for food allergies and atopy.

Questionnaire based assessment of peanut allergy validated by challenges.

Infant weaning for peanut and other foods was determined in infants using a validated FFQ.

Du Toit G et al. J Allergy Clin Immunol 2008; 122: 984-91.

Early consumption of peanuts in infancy is associated with a low prevalence of peanut allergy

Du Toit G et al. J Allergy Clin Immunol 2008; 122: 984-91.

0

0.2

0.4

0.6

0.8

1

1.2

1.4

1.6

1.8

2

United Kingdom Israel

Prevalence of Peanut Allergy in Children 4-18yrs

% P

A P

reva

len

ce

1.85%

0.17%

United Kingdom 5171

Israel 5615

p < 0.001

0

1

2

3

4

5

6

7

8

United Kingdom Israel

Peanut Protein Consumption 8-14 month

Me

dia

n g

ms

of

pe

an

ut

pro

tein

/ w

ee

k

0 g/week

7.1 g/week

p < 0.001

Canadian Position StatementJoint statement of CSACI and CPS

Do not delay the introduction of any specific solid food beyond six months of age. Later introduction of peanut, fish or egg does not prevent, and may even increase, the risk of developing food allergy. (Evidence II-2B)

Chan E and Cummings C, Paediatr Child Health 2013;18(10):545-9

LEAP StudyLearning Early About Peanut allergies

Learning Early About Peanut Allergy (LEAP Study)

4-11 months 1 yr 2.5 yr 5 yr♦

Randomisation/Stratification

4-11 month old children

eczema and/or egg allergy

Screening

Intervention group Peanut consumed 3 times per week(n≈320)

Control GroupPeanut avoidance (n≈320)

V 0 V 12 V 30 V 60V -1

Issues

What about SPT > 4 mm? Does it need to be 6 g of PN protein per week? What if gaps in regular consumption? What about general population? What about other foods…milk, eggs, tree nuts?

EAT Study - Early Weaning TrialInfants exclusively breastfed (EBF) at 3 months of age

1302subjects

Early introduction (4 months of age) of

allergenic foods & breastfeeding

1 and 3 yr assessment

Food allergy

Eczema

Atopic wheeze

Cumulative allergy

6 months EBF (UK infant feeding guidelines)

Randomization (3 months)

Moving forward

Well done study: randomized, prospective, controlled Results clearly show that in this “at risk” group, early

introduction of PN dramatically decreases the risk of development of PN allergy (70-80%)

Guideline changes are “in the works”

What does this mean to MDs?

Need for GPs and pediatricians to recognize these “at risk” children and refer them ASAP

Need for allergists to find a way to see these infants in a timely manner, so not to delay introduction

Need to change mindset of population towards early introduction.

Need to get the message out Statements and guidelines coming

Thank You