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How to manage food
allergy
Dr Andrew Clark
Consultant in Paediatric Allergy
Addenbrooke's Hospital
Food allergy in children
and young people
Implementing NICE guidance
February 2011
NICE clinical guideline 116
Food allergies
• Straightforward approach to diagnosis of
immediate and delayed type food allergy
• New presentations of food allergy
Epidemiology
Common: 8% of children; 2-3% adults
But 25–40% of adults think they are
allergic
Cornerstone: ruling it in and ruling it out
Assessment and allergyfocused clinical history (1)
The Skin
IgE- mediated
Non-IgE-mediated
Pruritus
Pruritus
Erythema
Atopic eczema
Erythema
Acute urticaria
Acute angioedema
Assessment and allergyfocused clinical history (2)
The gastrointestinal system
IgE- mediated
Angioedema of the lips, tongue
and palate
Oral pruritus
Nausea
Colicky abdominal pain
Vomiting
Diarrhoea
Non-IgE-mediated
Loose or frequent stools
Gastro-oesophageal reflux disease
Abdominal pain
Infantile colic
Food refusal or aversion
Constipation
Perianal redness
Pallor and tiredness
Faltering growth in conjunction with
at least one or more gastrointestinal
symptoms above
BSACI guidelines for the management
of Egg Allergy
Andrew Clark
Isabel Skypala
Susan Leech
Pamela Ewan
Pierre Dugué
Nicole Brathwaite
Pia Huber
Shuaib Nasser
CEA 2010; 40:1116, CEA 2011; 41: 706
Diagnosis of IgE-mediated
food allergy (2)
– Take an allergy-focused clinical history
– Tests should only be undertaken by healthcare
professionals with the appropriate
competencies to select, perform and interpret
them.
– Do not use atopy patch testing or oral food
challenges in primary care or community
settings.
Clinical case
8 month girl
– Mild eczema
Presents to primary care
2 spoonfuls of scrambled eggs
– Urticaria on face and chest
– No respiratory symptoms
– Resolved with oral AHs
CEA 2010; 40:1116, CEA 2011; 41: 706
1. do you…?
1. Refer to an allergy clinic?
2. Tell to try egg again to make sure?
3. Perform an egg-specific IgE test?
4. Advise to avoid egg?
CEA 2010; 40:1116, CEA 2011; 41: 706
Diagnosis
History
– Type of egg
– Hx of Eczema / asthma 90-100%
– Angioedema / urticaria
80-90%
– Abdominal pain / vomiting 10-44%
– Severe features
<5%
• Wheeze, voice change, stridor, DIB
• Floppy / collapse
CEA 2010; 40:1116, CEA 2011; 41: 706
IgE food allergy - rule it in
Genuine type-1 hypersensitivity reactions to
food are easy to spot with a few clues:
– History of eczema, asthma, rhinitis
– Rapid onset: within 1 hour of ingestion
– Local mucosal symptoms (itching in mouth
etc)
– Rapid resolution (<6 hours)
– Urticaria/angioedema/wheeze/laryngeal
oedema
– Recognised allergen (e.g. peanut, egg, milk)
– Usually obvious within 1-2 episodes
Rule it out - urticaria
Comes to see you after 10-20 episodes
No consistent precipitant
Reactions without precipitant
Unusual precipitant e.g. food colourings
Long interval before apparent reaction e.g. the
next day
Long duration of apparent reaction e.g. more
than 6 hours
More likely to be chronic urticaria
Diagnosis of IgE-mediated
food allergy (1)
– If IgE-mediated food
allergy is suspected,
offer a skin prick test
and/or blood tests
– Skin prick tests should only be
undertaken where there are
facilities to deal with an
anaphylactic reaction.
Serum specific IgE
CEA 2010; 40:1116, CEA 2011; 41: 706
Providing information and
support (2)
– Provide information to parents of babies or young
children with suspected allergy to cows’ milk protein
Anaphylaxis Campaign
– Offer information about the support available and
details of how to contact support groups
Clin Exp Allergy 2010; 40:1116, CEA 2011; 41: 706
Egg allergy
Management?
– Egg avoidance advice
– Initially avoid all egg from raw to well-cooked
– PIS available in BSACI guideline
CEA 2010; 40:1116, CEA 2011; 41: 706
Emergency medication
Majority mild allergy - oral antihistamines
IM adrenaline AI for severe symptoms or
asthma
– Referral
CEA 2010; 40:1116, CEA 2011; 41: 706
Milk allergy
More complex presentation
Common
– Delayed and immediate (IgE) types
Think of delayed type in infants who
Have
– Colick and reflux
– Eczema
Diagnosis of nonIgE-mediated food allergy
If non-IgE-mediated food allergy is suspected:
– trial elimination of the suspected allergen and
reintroduce after the trial: 6/52
– [seek advice from a registered dietician with
appropriate competencies]
Non-IgE mediated food allergy
“Intolerance”
Delayed reactions: hrs to days
Typical scenarios
– Colicky, vomity, eczematous infant (milk)
– Most common intolerance picture
– CM replacement with hypoallergenic formula
– 60-80% improvement in symptoms
– Manage expectations regarding allergy
Non-IgE mediated food allergy
Typical scenarios
– 2-5yr old with “difficult” eczema
– Parents don’t want to use corticosteroids
– Drinking cow’s milk since birth
– 6 weeks CM elimination
– No better
– Concentrate on medical Rx
Non-IgE mediated food allergy
Typical scenarios
– 5yr old with nocturnal cough + snoring
– Never wheezes
– Salbutamol ineffective
– 6 weeks CM elimination
– No improvement
– Oral antihistamines for post nasal drip
Non-IgE mediated food allergy
Typical scenarios
– 6 yr old girl with recurrent abdominal pain and
bloating
– Coeliac’s negative
– 6 weeks cow’s milk elimination
– 6 weeks wheat elimination
– Improvement
– ?why
Management of CMPA
• Food avoidance advice for breast feeding
mothers
• Hypoallergenic formulae
• Access to dietician
Hypoallergenic formulae
Partially hydrolysed
– Nutramigen
– Aptamil Pepti
Soya
– Phyto-oestrogens (not for boys<6m)
– Solids
Rice
– Arsenic
Goat / sheep etc…
Egg and milk allergy
Management?
– Reassure as most resolve spontaneously
– Re-introduction advice
When to reintroduce?
What sort of egg / milk?
How well cooked?
CEA 2010; 40:1116, CEA 2011; 41: 706
Timing of resolution
1.1
1.0
Proportion with egg allergy
0.9
0.8
Raw egg
0.7
Baked egg
30%
resolution
0.6
0.5
0.4
0.3
0.2
0.1
0.0
0
12
24
36
48
60
72
84
96
108 120 132 144 156 168 180 192
Age (months)
Reintroduction
• Cooked egg / milk first: cake
• Look for accidents in the history
• If tolerates cake already then continue
• Previous mild allergy, no asthma
– 2-3 yrs introduce well cooked allergen
– ??when to introduce less-well cooked??
– referral
Food allergy – referral I
Faltering growth +
– gastrointestinal symptoms
– not responded to a single-allergen elimination
diet
One or more acute systemic reactions
One or more severe delayed reactions
IgE-mediated food allergy and concurrent
asthma
Significant atopic eczema where food
allergies are suspected by the parent or
carer
Food allergy – referral II
Persisting parental suspicion of food allergy
Strong clinical suspicion of IgE-mediated
food allergy but
– allergy test results are negative
Clinical suspicion of multiple food allergies
Referral to allergy clinic
•Children with previous egg allergy symptoms that affected breathing
(cough, wheeze or swelling of the throat, e.g. choking), the gut (severe
vomiting or diarrhoea), or the circulation (faintness, floppiness or shock),
•Children who also receive regular asthma preventative treatment and/or
have poorly controlled asthma
•Where diagnosis is not clear and needs to be confirmed or excluded
•Severe eczema in children on an egg-containing diet
•Persistent or adult-onset egg allergy
•Egg allergy with requirement for influenza or yellow fever immunisation
•Egg allergy with another major food allergy
MMR and egg allergy
Appropriate to give in primary care to all
children with egg allergy, regardless of
previous egg reaction severity
Please refer: Children who have had anaphylaxis to the actual
vaccine before
CEA 2010; 40:1116, CEA 2011; 41: 706
Influenza vaccine
CEA 2010; 40:1116, CEA 2011; 41: 706
Clinical case
3 year old boy
– 6m old, urticaria after scrambled eggs
– Tolerates cooked egg but mouth itching with
mayonnaise
– Asthma, well controlled on low-dose ICS
– Presents for influenza vaccine?
CEA 2010; 40:1116, CEA 2011; 41: 706
Clinical case
20 year old male
– Persistent egg allergy since childhood
– Frequent reactions to contamination:
lip angioedema and wheeze
– Asthma; stage 4 BTS Rx
CEA 2010; 40:1116, CEA 2011; 41: 706
Influenza vaccination
Indications
– >6m age
– asthma treated with continuous or repeated
use of inhaled or systemic corticosteroids or
with previous exacerbations requiring hospital
admission
Contra-indications
– Previous anaphylaxis to vaccine
CEA 2010; 40:1116, CEA 2011; 41: 706
Is vaccination
indicated?
No
Influenza vaccination in eggallergic individuals
Yes
Anaphylaxis
to egg?
Yes
No
Vaccinate
in Hospital
Asthma ≥SIGN 4?
Yes
Vaccinate
in Hospital
No
Vaccinate in
primary care
Influenza vaccines for the 2011/12 season
Product
Pharmaceutical
Company
FluarixGSK
GlaxoSmith Kline
Intanza 9 µg
Sanofi Pasteur
MSD
Intanza 15 µg Sanofi Pasteur
Ovalbumin
content
(per dose)
< 0.05 µg
Grown in
Age
Indication
< 0.024 µg
chick
embryos
hens' eggs
6m
18-59yr
< 0.024 µg
hens' eggs
60yr
chick
embryos
chick
embryos
6m
MSD
Split Virion
BP
Sanofi Pasteur
< 0.024 µg
Viroflu /
Crucell UK Ltd
< 0.05 µg
Inflexal V
Egg-free vaccine (Preflucel®; >18y only) withdrawn
Pia Huber
CEA 2010; 40:1116, CEA 2011; 41: 706
6m
New patterns of reaction
New patterns of reaction
22 year old man
– Allergic rhinitis in the spring
– Recent onset of lip swelling and mouth itching
when eating raw apples, pears and cherries
– Hazelnuts also make his mouth itch
– Positive IgE tests to fruit, tree pollen and nuts
Pollen fruit syndrome (oral allergy
syndrome)
• Primary disease is allergy to birch pollen
protein (Bet v 1)
• Cross-reacting to homologous protein in
fruit and nuts (Mal d 1 - apple)
• Generally mild reactions, even to nuts
– Fruit tolerated if heated
Pollen
Apple
New patterns of reaction
• 31 year old female
• History of eczema
• Ate small amount of kiwi fruit
– Severe burning sensation in mouth
– Throat tightening
– Wheeze
– Rx with IM adrenaline in ED
Lipid transfer protein (LTP) allergy
• Severe reactions to fruits due to LTP
reactivity
• Heating fruit does not reduce allergenicity
Also peach “Pru p 3”
Clinical Case
• 24 year old female
• Reaction in nightclub, shortly after starting
to dance
– Generalised urticaria, lip angioedema and
wheeze
• Normally eats at 8pm and goes to club at
12pm, on this occasion pasta at 10pm
• Eats wheat on other occasions without
reacting
Food Dependent Exercise Induced
Anaphylaxis (FDEIA)
• Commonly wheat protein is the trigger
– Omega-5-gliadin IgE positive
• Patients tolerate ingestion unless exercise
within 4hrs
• Anaphylaxis
• Advise to increase gap before exercise
Clinical Case
• 68 year old male
• Recent onset of swelling of tongue and
lower lip in evening, usually after eating
• Swelling subsides within a few hours
• Past history
– Hypertension
ACE inhibitor induced angioedema
• Associated with ACEIs
• Can begin years after first prescription
• Fatalities
• Treatment
– Stop ACEI and provide alternative
• Risk continues for several months after
stopping ACEI
Summary
Allergy-focused history usually determines
diagnosis
Allergy testing
Vaccination
Referral
New presentations
Secretary
Caron Nolan
carol.nolan@addenbrookes.nhs.uk
01223 596 185
fax 01223 216 953