Thank you for the feedback. You're right that I should consider the pre-test probability and clinical context when evaluating test results.

1. Food Allergy Update
Katherine Noble MD | “Dr. Katy”
November 17, 2016
Old Greenwich School

2. Should We Be Concerned About Food
Allergy?

3. YES !!!
 Food allergy affects 1 in approximately 25 children – up
to 8% of school aged children
 Food allergy in children is on the rise
 Food allergy impacts all childhood settings from daycares, to
preschools and schools, to camps and to homes across the
country

4. Objectives
 It is important to develop an understanding of any health
issue based on scientific evidence from reliable resources
 My objectives today:
build your knowledge about food allergy
empower you to better care for your family
support OGS in being a safe environment for
children with food allergies

5. Outline: what’s on the menu for today!
 Food allergy basics: sources of food allergy,
signs and symptoms, prevention, treatment
 Food allergies in school: key considerations
 Practical pointers: keeping food-allergic kids
safe

6. Food allergy defined and explained
Food allergy is defined as an “abnormal immunologic
reaction to food”
“Allergy” and ”hypersensitivity” are terms often used
interchangeably

7. Food allergy defined and explained
 Allergic reactions to food of the type that most parents,
caregivers and school personnel are concerned about are
mediated by immunoglobulin E molecules (IgE) in the body

8. Food allergy defined and explained
 Non-IgE mediated food allergies and mixed IgE/ non-IgE
mediated food allergies also exist but are not the focus of my
talk today

9. Oral food allergy: a unique entity
 Oral allergy syndrome  oral symptoms with exposure to
primarily raw fruits & certain vegetables
 It is a food–pollen syndrome – occurring in patients with high
sensitivity to certain pollens (usually tree pollens)
 Cooking the food eliminates the sensitivity and is often
diagnostic of this syndrome
 It usually does not require an Epi Pen

10. Associated conditions
Children with food
allergies/sensitization are at increased
risk of developing seasonal allergies
(”allergic rhinitis”) and asthma later on
in life
And … children with eczema,
seasonal allergies and asthma are
more likely to have a food allergy

11. Allergenic foods

12. Common culprits
 In young children, 90% of IgE-mediated food allergies are caused
by
 Cow’s milk
 Egg
 Soy
 Peanut or tree nut
 Wheat
 Fish & shellfish
 Allergies to fruits & vegetables are common but less severe
 Allergies to seeds (sesame, poppy, canola) are on the rise

13. Food allergy onset & prevalence over time
 Food allergy generally begins before age 2 years
 Food sensitization (and/or allergy) affects 5-10% of young
children, with a peak prevalence at age 1y (6-8%)
 Prevalence of food allergy later in a child’s life plateaus at about
3-4%

14. What does an allergic reaction look like?

15. Common signs & symptoms of food
allergy
Skin findings
Flushing
Itching
Hives
Angioedema: swelling of lips, face

16. Common signs & symptoms of food
allergy
Cardio/respiratory findings
Throat closure
Wheezing
Low blood pressure (hypotension)

17. Common signs & symptoms of food
allergy
Gastrointestinal findings
Nausea & vomiting
Cramping
Diarrhea

18. Food allergy can present clinically
differently in children and adults
 Children commonly present with VOMITING & HIVES
 Adults commonly present with HIVES, ANGIOEDEMA, AND
ABDOMINAL SYMPTOMS

19. Timing of onset after food exposure
 Usually reactions begin rapidly (seconds to minutes) after
ingestion of the offending allergenic food
 Uncommonly, reactions can start up to 2 hours after exposure
and beyond

20. Treatment
 Benadryl (mild reactions)
 Epi Pen (severe reactions)
 Oral steroids (useful
adjunctive therapy)

21. Prevention
AVOIDANCE

22. If you think your child has a food allergy … don’t
attempt to figure this out yourself
See your pediatrician and an allergist if
recommended ... and let them guide the testing
If your child has had a severe reaction, an allergist’s
evaluation is absolutely critical

23. The diagnostic evaluation of food allergy:
It is not straightforward!
History is the critical element: it guides testing and
interpretation of results
A child with no history of food allergy should not have routine
testing performed unless there is a strong family history of food
allergy
Blood testing (tests for IgE-antibodies in blood)
Skin prick testing
Oral food challenge

24. Blood testing (IgE)
 Less sensitive than skin prick tests
 Widely available
 Unaffected by antihistamines or medications
 Useful in patients with skin conditions like severe eczema, that
might affect skin prick test interpretation
 Useful in patients in whom skin testing is too dangerous
(history of severe anaphylaxis)
 Useful in tracking food allergy over time

25. Blood testing: IgG ????
NO
IgG blood testing is not useful and is
misleading

26. Skin prick testing

27. Skin prick testing
 Food allergen is applied to the skin
 A positive result: wheal of at least 3mm in diameter, after
saline control is subtracted
 The larger the reaction, the greater the likelihood of clinical
allergy

28. Skin prick testing
 Skin tests are very useful in excluding an IgE-mediated food
allergy
 A negative test typically confirms the absence of an IgE-mediated
reaction (90-95% accuracy)
 Skin testing should not be performed right after a serious
allergic reaction – as the test may be falsely
nonreactive/negative.

29. Oral food challenge
 Sometimes required to make a clear diagnosis of food
allergy
 Should not be performed in children in whom a severe
allergy is suspected (due to safety)
 Required to clear children with a history of food allergy
in whom it is suspected to have been outgrown
 Should ALWAYS be performed in an allergist’s office
with appropriate medications and emergency equipment
to address an anaphylactic reaction

30. Outgrowing food allergy: setting
expectations
 Most childhood food allergies are
outgrown, and lost in childhood or
adolescence
 Fish/shellfish & peanut/tree nut
allergies are less likely outgrown
 Children with higher levels of food
specific IgE levels are less likely to
outgrow their allergy and become
“tolerant.”
 Negative tests do NOT guarantee loss
of the allergy – an oral food challenge
is required

31. Fatal reactions
 Rare events
 More common in adolescents and young adults  higher risk
behaviors? not carrying Epi Pen? intentional ingestion?
 Peanut is the most common culprit
 Prompt administration of epinephrine is paramount

32. If you believe your child has a food allergy…
 DO NOT RESTRICT YOUR CHILD FROM EATING VARIOUS FOODS
UNLESS THERE IS A CONFIRMED OR HIGHLY SUSPECTED FOOD
ALLERGY. SEE YOUR PEDIATRICIAN AND/OR AN ALLERGIST.
 Some studies have shown that food avoidance can actually bring
forth a serious food allergy
 Blood tests are not really meaningful without the clinical history and a
high-index of suspicion of food allergy … random blood testing may lead
to inappropriate food avoidance

33. Food allergies in schools are a challenge
 Sending a food-allergic child to school or daycare can be very
anxiety-provoking for parents …
 Creating a safe environment in the school can be a challenge:
Avoiding food allergens in the classroom can be more
challenging than you think
 Cooking lessons
 Art projects
 Math instruction
 School supplies: modeling clay, paints may contain allergenic
components
 Birthday parties in the classroom

34. Characteristics of reactions in schools
 Food reactions in schools are not rare
events
 One study reported that 39% of schools
experienced a food allergic event during the
prior 2 years
 Milk and peanut reactions are the most
common type to occur at school

35. Characteristics of reactions in schools:
What have studies shown?
 Reactions can occur outside of the
school: playgrounds, traveling to and
from the school and on field trips
 Celebrations and craft foods are
commonly the source of allergic
reactions
 A significant percentage of children
who had reactions, had no known
food allergy and experienced their
first reaction at school

36. The tough reality is that food
reactions are unavoidable and
inevitable

37. Managing food allergy in school requires a
coordinated approach
SCHOOL, PARENT, CHILD, DOCTOR
 Institutional food allergy management plan
 Personal food allergy action plan
 Physician
 Staff education
 Bus safety
 Parent responsibility
 Child responsibility: to the extent able

38. Staff Education
 Can staff recognize a food allergic
reaction?
 Can staff access epinephrine quickly?
 Do staff know when and how to use
the Epi Pen?
 Can staff administer epinephrine
without first having to contact the
child’s parent or find the school
nurse?

39. Parent responsibility
 Current, accurate and detailed food allergy action plan
 Suggested food alternatives
 Medication: make sure all care providers know how to use
the Epi Pen!
 Parents: please keep your child’s doctor informed and up to
speed!
 Be aware of bullying related to food allergy and act in defense
of your child if and when it occurs

40. Food-allergic child responsibility
 Don’t trade foods!
 Avoid eating anything that might
contain the allergen or foods with
unknown ingredients
 Wash hands before and after eating
 Get involved and engaged in
managing the allergy
 Notify an adult if he or she suspects a
reaction has begun
 “Know your Epi Pen”
 Notify an adult if there is bullying
occurring

41. Minimize risk at school: ideas worthy of
consideration
 No food trading
 Peanut ban
 No food in classrooms
 No homemade food
 Involve parents of food-allergic students to select foods for class
celebrations
 Celebrate birthdays without foods
 Provide allergy safe tables in the cafeteria
 School-wide food allergy education and management plans
 Food allergy awareness program for all students

42. Practical pointers

43. Minimizing risks at school & at home:
provide a safe environment
 Cleaning desk tops and tables:
Plain water
Formula 409
Lysol sanitizing wipes
Target-brand cleaner with bleach

44. Minimizing risks:
provide a safe environment
 Removing peanut residue from adult hands:
Tidy Tykes Wipes
Wet Ones antibacterial wipes
Liquid soap
Bar soap
Plain water and hand sanitizer does NOT work

45. Minimizing risks:
provide a safe environment
 In a home with a food allergic child: Avoiding keeping
allergenic foods in the house if you can. Otherwise, keep
these foods in a separate space.
 Use your dishwasher
 Beware of your toaster
 Use plastic cutting boards which are easier to clean than
wood

46. CASE STUDY

47. MEET MY NEPHEW
ANGUS….

49. ANGUS….
 Hives and facial swelling occurred
within a few minutes of ingesting
pasta with pesto sauce, made with
walnuts, at a local restaurant
 Brought to emergency department
for treatment
 Subsequent testing was positive for
walnuts and “equivocal” for peanut
 Mother was advised to give a peanut
butter oral challenge at home….

50. I said: “That doesn’t seem like a good idea, Kyra
…. Why don’t you ask for food challenge in the
allergst’s office instead?”
 What happened??
 My sister took Angus back to the allergist for the peanut oral challenge
 Angus developed an anaphylactic reaction in the office
 His reaction was treated successfully with an Epi Pen injection
 He has since outgrown his peanut allergy … but continues to be
allergic to walnuts/ tree nuts and always has an Epi Pen handy

51. What happened ??
 My sister took Angus back to the allergist for the peanut oral
challenge
 Angus developed an anaphylactic reaction in the office
 His reaction was treated successfully with an Epi Pen injection
 He has since outgrown his peanut allergy … but continues to be
allergic to walnuts/ tree nuts and always has an Epi Pen handy

53. In Summary….
Food allergy is not clear cut!
Clinical history should guide testing
Do not remove food from your child’s diet based only upon
a positive test results
Any food avoidance should be guided by your allergist

54. In Summary….
For allergic kids:
Avoidance of the offending allergenic food is key!
Epi pens are life saving and need to be given promptly
An allergist should monitor a food-allergic child regularly –
often annually for most cases – to determine if the allergy
has been outgrown
Oral food challenge is typically required to determine if the
allergy is resolved

55. In Summary….
In the schools:
Success in food allergy management requires a coordinated
approach
 Food allergy is a big focus of medical research and is a
dynamic field… Recommendations are changing .... The
LEAP study is revolutionizing our thoughts and ultimately
our practice on early introduction of allergenic foods!
SO STAY
TUNED!!!

56. Should we be concerned about the effects of
electronic media on children?

57. Yes ….
 Electronic media is ubiquitous….
EVERYHWERE
 Children of all ages, races and socio-
economic statuses are exposed to
eletronic media daily
 We do not fully understand the effects
of electronics on the growing and
developing child brain

58. We should be spending at
least as much time thinking
about the electronics our
children “ingest” as the foods
they eat and the sports &
activities in which they play
and participate

62. Today’s talk is brought to you by …
 Up To Date: www.UpToDate.com
 With the review of Dr. Joseph Sproviero, Fairfield County
Allergy, Asthma and Immunology Associates (FCAAIA)
 For more about electronic media & children:
Dr. Michael Rich, “The Mediatrician,” and the Center on Media
and Child Health, Boston, MA (http://cmch.tv)

63. CASES from “Up To Date”
 Patient 1 has experienced two severe allergic reactions following the isolated
ingestion of scrambled egg, requiring and responding to treatment with
epinephrine on both occasions.
 Patient 2 has severe atopic dermatitis and eats egg regularly. He has never
experienced an apparent acute reaction to egg. However, his mother is aware that
food allergy can exacerbate this condition and has therefore requested an allergy
evaluation
 Patient 3 has no history of allergic problems, but her parents think she
“misbehaves” after eating eggs.

64. CASES from “Up To Date”
 Patient 1 has a very high pretest probability of egg allergy, so
a moderately positive test is sufficient to validate the clinical
suspicion. The patient should be referred to an allergy
specialist for confirmatory skin testing, which is more specific
 If the in vitro test had been negative, the pediatrician would
be correct to question the result and refer the child to an
allergy specialist for further evaluation.

65. CASES from “Up To Date”
 Patient 2 has a moderate pretest probability since up to 40
percent of children with moderate to severe atopic dermatitis
have underlying food allergy, and egg is a common cause of
childhood food allergy [In this patient, the positive result is
suggestive of true allergy, although further evaluation is
needed to demonstrate that egg allergy is contributing to skin
inflammation.

66. CASES from “Up To Date”
 Patient 3 has an extremely low pretest probability, and the
test result is not sufficiently positive to impact the clinician's
initial impression. This case also illustrates one of the
disadvantages of performing testing in patients whose
histories are not consistent with allergic disease, as irrelevant
results may confuse the situation.