food adverse reaction

Question 1

FOOD ALLERGY

Answer 1

• Food intolerance
o Adverse physiologic response
• Food allergy
o Adverse immunologic response and can be
immunoglobulin IgE mediated or non IgE mediated
• Prevalence 1-10%
• Up to 6% of children experience food allergy reaction in the
1st 3 years of life
• 2.5% cow’s milk allergy
• 1.5% egg allergy
• 1% peanut allergy
• 53% of children “outgrow” milk and egg allergy
• 80-90% of children with peanut, nut and seafood allergy
retain their allergy for life.

Question 2

Adverse Food Reactions>FOOD INTOLERANCE (NON–IMMUNE SYSTEM-MEDIATED,
NONTOXIC, NONINFECTIOUS)
Host factor

Answer 2

Enzyme deficiencies—lactase (primary or secondary), sucrase/
isomaltase, hereditary fructose intolerance, galactosemia
Gastrointestinal disorders—inflammatory bowel disease, irritable
bowel syndrome, pseudoobstruction, colic
Idiosyncratic reactions—caffeine in soft drinks (“hyperactivity”)
Psychologic—food phobias, obsessive/compulsive disorder
Migraines (rare

Question 3

Food factors (toxic or infectious or pharmacologic)

Answer 3

Infectious organisms—Escherichia coli, Staphylococcus aureus,
Clostridium perfringens, Shigella, botulism, Salmonella, Yersinia,
Campylobacter
Toxins—histamine (scombroid poisoning), saxitoxin (shellfish)
Pharmacologic agents—caffeine, theobromine (chocolate, tea),
tryptamine (tomatoes), tyramine (cheese), benzoic acid in citrus
fruits (perioral flare)
Contaminants—heavy metals, pesticides, antibiotics

Question 4

FOOD ALLERGY
IgE-mediated

Answer 4

Cutaneous—urticaria, angioedema, morbilliform rashes, flushing,
contact urticarial
Gastrointestinal—oral allergy syndrome, gastrointestinal anaphylaxis
Respiratory—acute rhinoconjunctivitis, bronchospasm
Generalized—anaphylactic shock, exercise induced anaphylaxis

Question 5

Mixed IgE- and non–IgE-mediated

Answer 5

Gastrointestinal—allergic eosinophilic esophagitis and
gastroenteritis
Respiratory—asthma

Question 6

Non–IgE-mediated

Answer 6

Cutaneous—contact dermatitis, dermatitis herpetiformis (celiac
disease)
Gastrointestinal—food protein–induced enterocolitis, proctocolitis,
and enteropathy syndromes, celiac disease, food protein induced
enteropathy
Respiratory—food-induced pulmonary hemosiderosis (Heiner
syndrome)
Unclassified

Question 7

Differential Diagnosis of Adverse Food
Reactions
GASTROINTESTINAL DISORDERS (WITH VOMITING AND/OR
DIARRHEA

Answer 7

Structural abnormalities (pyloric stenosis, Hirschsprung disease,
reflux

Question 8

Differential Diagnosis of Adverse Food
Reactions>Enzyme deficiencies (primary or secondary):

Answer 8

Disaccharidase deficiency—lactase, fructase, sucrase-isomaltase
Galactosemia
Malignancy with obstruction
Other: pancreatic insufficiency (cystic fibrosis), peptic disease

Question 9

CONTAMINANTS AND ADDITIVES

Answer 9

Flavorings and preservatives—rarely cause symptoms:
Sodium metabisulfite, monosodium glutamate, nitrites
Dyes and colorings—very rarely cause symptoms (urticaria, eczema):
Tartrazine
Toxins:
Bacterial, fungal (aflatoxin), fish-related (scombroid, ciguatera)
Infectious organisms:
Bacteria (Salmonella, Escherichia coli, Shigella)
Virus (rotavirus, enterovirus)
Parasites (Giardia, Akis simplex [in fish])
Accidental contaminants:
Heavy metals, pesticides
Pharmacologic agents:
Caffeine, glycosidal alkaloid solanine (potato spuds), histamine
(fish), serotonin (banana, tomato), tryptamine (tomato), tyramine
(cheese)

Question 10

PSYCHOLOGIC REACTIONS

Answer 10

Food phobias

Question 11

Natural History of Food Allergy and Cross-Reactivity Between Common Food Allergies

Answer 11

Hen’s egg white 0-1 yr Other avian eggs 7 yr (75% of cases resolve)

Question 12

Natural History of Food Allergy and Cross-Reactivity Between Common Food Allergies

Answer 12

Cow’s milk 0-1 yr Goat’s milk, sheep’s milk, buffalo milk 5 yr (76% of cases resolve)*

Question 13

Natural History of Food Allergy and Cross-Reactivity Between Common Food Allergies

Answer 13

Peanuts 1-2 yr Other legumes, peas, lentils; coreactivity
with tree nuts
Persistent (20% of cases resolve)

Question 14

Natural History of Food Allergy and Cross-Reactivity Between Common Food Allergies

Answer 14

Tree nuts 1-2 yr; in adults, onset occurs after cross
reactivity to birch pollen
Other tree nuts; coreactivity with peanuts Persistent (9% of cases resolve)

Question 15

Natural History of Food Allergy and Cross-Reactivity Between Common Food Allergies

Answer 15

Fish Late childhood and adulthood Other fish (low cross-reactivity with tuna
and swordfish)
Persistent†

Question 16

Natural History of Food Allergy and Cross-Reactivity Between Common Food Allergies

Answer 16

Shellfish Adulthood (in 60% of patients with this
allergy)
Other shellfish Persistent

Question 17

Natural History of Food Allergy and Cross-Reactivity Between Common Food Allergies

Answer 17

Shellfish Adulthood (in 60% of patients with this
allergy)
Other shellfish Persistent

Question 18

Natural History of Food Allergy and Cross-Reactivity Between Common Food Allergies

Answer 18

Wheat* 6-24 mo Other grains containing gluten (rye, barley) 5 yr (80% of cases resolve)

Question 19

151-3 Natural History of Food Allergy and Cross-Reactivity Between Common Food Allergies

Answer 19

Soybeans* 6-24 mo Other legumes 2 yr (67% of cases resolve)

Question 20

Natural History of Food Allergy and Cross-Reactivity Between Common Food Allergies

Answer 20

Kiwi Any age Banana, avocado, latex Unknown

Question 21

Natural History of Food Allergy and Cross-Reactivity Between Common Food Allergies

Answer 21

Apples, carrots,
and peaches§
Late childhood and adulthood Birch pollen, other fruits, nuts Unknown

Question 22

Prevention of Food Allergy

Answer 22

Exclusive breast feeding for 4-6 mo
Introduce solid (complementary) foods after 4-6 mo of exclusive
breast feeding
Introduce low-risk complementary foods 1 at a time
Introduce potentially highly allergenic foods (fish, eggs, peanut
products, milk, wheat) soon after the lower-risk foods (no need to
avoid or delay)
Don’t avoid allergenic foods during pregnancy or nursing
Soy-based formulas do not prevent allergic disease

Question 23

Symptoms of Food-Induced Allergic
Reactions

Answer 23

Cutaneous Erythema
Pruritus
Urticaria
Morbilliform eruption
Angioedema

Erythema
Flushing
Pruritus
Morbilliform
eruption
Angioedema
Eczematous rash

Question 24

Symptoms of Food-Induced Allergic
Reactions

Answer 24

Ocular Pruritus
Conjunctival erythema
Tearing
Periorbital edema

Delayed
Pruritus
Conjunctival
erythema
Tearing
Periorbital edema

Question 25

Symptoms of Food-Induced Allergic Reactions

Answer 25

Upper respiratory Nasal congestion Pruritus Rhinorrhea Sneezing Laryngeal edema Hoarseness Dry staccato cough

Question 26

Symptoms of Food-Induced Allergic Reactions

Answer 26

Lower respiratory Cough Chest tightness Dyspnea Wheezing Intercostal retractions Accessory muscle use Cough, dyspnea, and wheezing

Question 27

Symptoms of Food-Induced Allergic Reactions

Answer 27

GI (oral) Angioedema of the lips, tongue, or palate Oral pruritus Tongue swelling

Question 28

GI (lower

Answer 28

GI (lower) Nausea Colicky abdominal pain Reflux Vomiting Diarrhea Nausea Abdominal pain Reflux Vomiting Diarrhea Hematochezia Irritability and food refusal with weight loss (young children)

Question 29

Cardiovascular

Answer 29

Tachycardia (occasionally bradycardia in anaphylaxis) Hypotension Dizziness Fainting Loss of consciousness

Question 30

Miscellaneous

Answer 30

Uterine contractions Sense of “impending doom”

Question 31

PATHOGENESIS

Answer 31

• Exposure to allergen → formation of food specific antibodies → bind to the Fc receptor of mast cells, basophils, macrophage, & dendritic cells → penetrate mucosal barrier & reach cell-bound IgE antibodies → mediators are released → vasodilation, smooth muscle contraction, mucus secretion →symptoms of immediate hypersensitivity (allergy) • Skin: oral pruritus, angioedema, flushing • GIT: oral pruritus, angioedema, nausea, abdominal pain, vomiting, diarrhea • Respiratory: nasal congestion, rhinorrhea, nasal pruritus, sneezing, laryngeal, edema, wheezing • Cardiovascular: dysrhythmia, hypotension, loss of consciousness. • Delayed type o Activated macrophage and mast cells release cytokines that attract and activate cells, cells like eosinophils and lymphocytes → prolong/ chronic inflammatio

Question 32

Class 1

Answer 32

Class 1 food allergen: allergens penetrating the GI barrier o Cell mediated sensitivity • 90% of food allergen occurring in children: egg, milk, peanuts, treenuts, fish, soy and wheat • All milk allergy occurs by 12 mos of age • All egg allergy by 18 mos of age • Median age of first peanut allergic reaction is 14 mos • Current recommendation: o Introduce egg peanut products, fish, wheat, and all allergic food after 4-6 mos of exclusive breastfeeding (gradually introduce these allergenic foods during complimentary feeding to develop tolerance)

Question 33

Class 2

Answer 33

• Class 2 food allergen: food allergen partially homologous to plant pollens penetrating the respiratory tract (Bigger table below) CLINICAL MANIFESTATION • Skin Manifestation: 1. AD – at least 30% of children with moderate to severe AD has food allergy 2. Acute urticaria and angioedema o Most common symptom of food allergic reactions o Onset is rapid within minutes of ingestion o Egg, milk, peanuts & nuts 3. Perioral dermatitis o Contact dermatitis o Toothpaste, gum, lipstick 4. Perioral flushing – noted in infants fed with citrus fruit caused by benzoic acid (orange fruit) • Respiratory Manifestation: o Uncommon o Wheezing occur in 25% of IgE allergic reaction o 10% of asthmatic patients have food-induced respiratory symptoms DIAGNOSIS •

Question 34

DIAGNOSIS

Answer 34

• Thorough medical history (food eaten prior to the onset of signs and symptoms) • IgE mediated food reaction o Skin prick test o Serum specific IgE level • Cell mediated o Elimination diet followed by food challenges o 10-14 days for IgE mediated for food allergy

Question 35

TREATMENT

Answer 35

• Appropriate identification and elimination of food • Children with asthma and IgE mediated food allergy, peanut, or nut allergy or with history of previous severe reaction should be given epinephrine and a written emergency plan (ideally, they should have their EpiPen whenever they go outside their house)

Question 36

TREATMENT

Answer 36

• Appropriate identification and elimination of food • Children with asthma and IgE mediated food allergy, peanut, or nut allergy or with history of previous severe reaction should be given epinephrine and a written emergency plan (ideally, they should have their EpiPen whenever they go outside their house)

Question 37

PREVENTION

Answer 37

• No consensus as to whether food allergen can be prevented • Exclusive breastfeeding • Partially hydrolyzed whey food • Probiotic supplementation • Avoid peanut oil containing skin preparation