Food Allergies in Infants and Children

• Shana Spector

Food Allergies in the U.S.

• More than 6 million Americans suffer from food allergies

• 3 million specifically allergic to peanuts, walnuts, and pecans

• Other common food allergies: milk, fish, shellfish, wheat and soy

What Causes Allergic Reactions?

• Overactive immune system

• Body believes a substance is harmful

• Body wants to protect itself by fighting that substance off

• Immune system releases chemicals and histamine, triggering the reaction

IgE Mediated Allergy Disorder

• Cause acute onset of symptoms after digestion

• Affect skin, respiratory tract, gastrointestinal tract and cardiovascular system

IgE Mediated Allergy Disorder

• IgE antibodies are cells that are released from specialized B cells during contact with allergen

• IgE antibodies attach to IgE receptors on mast cells

IgE Mediated Allergy Disorder

• If the allergen is again presented in the body, it binds to surface of mast cell, triggering release of histamine and other chemicals

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Types of IgE Mediated Disorders

• Type 1 Hypersensitivity: most common disorder

• Symptoms include hives, swelling of face, itching, vomiting, diarrhea, coughing, wheezing and decrease in blood pressure

Types IgE Disorders

• Oral Allergy Syndrome

• Caused by allergies to fruits and veggies

• Itching swelling of lips, tongue, palate and throat

Types IgE Disorders

• Respiratory Hypersensitivity Reaction

• Effects respiratory tract

• Causes runny nose, nasal congestion, wheezing and coughing

Types IgE Disorders

• Airborne Food Allergy Reaction

• Transpires from smelling an allergen through cooking

• Causes nasal congestion, inflammation of the eyes and hives

Types IgE Disorders

• Food-Associated Exercise-Induced Anaphylaxis

• Occurs when allergic person exercises 2-4 hours after eating certain foods

• No reaction without exercise

• More common in females (esp. teenagers)

Other Food Disorders

• Subacute or chronic

• Usually affect gastrointestinal tract

• Mediated by T cells

• Mainly found in infants and children

• Usually caused by hypersensitivity to cow’s milk or soy

Symptoms of Food Allergies

• Hives are most common

• Other symptoms: tingling in mouth, swelling in the tongue and throat, difficulty breathing, abdominal cramps, vomiting, diarrhea, and eczema

Anaphylaxis

• Serious allergic reaction occurring within a few minutes to two hours after contact with allergen

• Acute and potentially fatal

• Causes 300,000 hospital visits and 150-200 deaths per year

Infants, Children and Food Allergies

• 6-8% of children develop food allergies within the first three years of life

• 90% of food allergies in kids involve cow’s milk, egg, peanut, wheat, soy, tree nuts, or fish

Infants, Children and Food Allergies

• Most children outgrow their allergies to milk, egg, wheat and soy by age 3-5

• Only 20% of infants with peanut allergy will eventually tolerate peanuts

Problems Associated with Food Allergies in Children

• Poor nutrient intake

• Constipation

• Eczema

• Potential death

Food Allergies Linked to Poor Growth

• Increased risk for poor nutrient intake

• Parents may eliminate too many foods from child’s diet or neglect to supplement

• In severe cases, children can develop failure to thrive

Studies Showing Poor Growth

• Children with one or more food allergies more likely to be under 25th percentile height for age than healthy children

• Subjects with 2 or more food allergies significantly shorter than children with 1

• Children with specific allergy to cow milk showed lower height for age than healthy children

What to do if Child has Food Allergies

• Consult with an allergist and dietician

• Use growth charts often to assess child’s growth

Food Allergies and Constipation

• Recent studies have linked infantile constipation to cow’s milk allergy

• Study shows infants switching to soy milk from cow milk alleviates constipation

• Study shows 5 year olds eliminating milk protein from diet and no longer suffering from constipation

Food Allergies and Atopic Dermatitis

• Atopic dermatitis: skin condition associated with food allergies in infants and children

• Atopy: refers to a tendency for excess inflammation in the skin, linings of the nose, and lungs

• Eczema usually runs in families

Food Allergies and Eczema

• 10% of infants suffer from eczema

• Skin becomes infected, with itchy rashes on face and scalp

Food Allergies and Eczema

• Study suggests that introducing solid food later in life will decrease prevalence of eczema

• Low-birth weight significantly correlated with a lower risk for food allergies and atopic dermitis

Potentially Deadly Reactions

• Most severe reactions in children: peanuts and other tree nuts

• Many are accidental: hidden nuts in brownies and cookies, peanut oil, etc.

• Symptoms progress with maturity

• Skin reaction during infancy to respiratory and gastrointestinal reactions later

Maternal and Familial Influence on Food Allergies

• Food allergies and atopy run in families

• 20% of children with eczema are the only one in family with problem

Maternal Influence and Possible Prevention

• Prevalence of peanut allergy is rising

• Pregnant women advised to eliminate peanuts from diet

• Allergy to peanuts may be preventable

Breastfeeding Mothers

• Breastfeeding may prevent food allergies and atopic dermatitis

• Can pass peanut allergy through breastfeeding

• It is recommended for mom to eliminate peanuts from diet while breastfeeding

Prevention of Cow’s Milk Allergy

• Hydrolysated formula

• Extensive or partially

• Only given to babies at high risk for atopic disease due to family history

Prevention of Cow’s Milk Allergy

• Babies given eHF combined with breast milk and no solid food until after 6 months of age

• Prevalence of food allergy and atopic dermatitis significantly reduced

• Babies given eHF or pHF: atopic disease greatly reduced in those given eHF

Diagnosis of Food Allergy

• What happens in the case of a mild reaction?

• What happens in the case of a severe reaction?

Tests and Procedures to Determine Food Allergy

• Skin Prick Test

• Identifies food specific IgE antibodies

• Test is either negative or positive

Tests and Procedures to Determine Food Allergy

• Radioallergosorbent Test (RAST)

• Done if test positive on SPT

• RAST is a blood test to determine food specific IgE

• RAST and SPT detect sensitization, but sensitization can occur without reaction

Elimination Diet

• Determines if given food is causing allergic reaction

• Food thought to be causing symptoms removed from diet

• Infants: change of formula or diet for breastfeeding mother

• Lasts 1-6 weeks

Food Challenge

• Also determines if specific food causes allergic reaction

• Performed under certain circumstances:

1)When several foods are under consideration, 2)IgE tests positive for several foods, and 3)elimination diet caused symptoms to end

Relevance to Parents

• Valuable for new parents and those thinking about reproducing

• May be able to prevent certain food allergies• Be aware: unusual symptoms of child may be

caused by food allergy• Education is Key: inform teachers, babysitters,

and any caretaker of child in order to prevent severe reactions