ATOPIC ECZEMA and the role of food allergy Amanda Woods Consultant Dermatologist Queen Mary’s Hospital Chelsea and Westminster Hospital December 2013
ATOPIC ECZEMA
and the role of
food allergy
Amanda Woods
Consultant
Dermatologist
Queen Mary’s Hospital
Chelsea and
Westminster Hospital
December 2013
ATOPIC ECZEMA
15-20%
children
in UK are
affected
GENETICS
• Loss of function mutations in gene encoding for filaggrin (2006) predisposes to atopic eczema
• Filaggrins are filament-associated proteins that bind to keratin fibres in epidermal cells
• Important in the barrier function of the outer layer of the epidermis
TREATMENT OF ATOPIC
ECZEMA FIRST LINE TREATMENTS
Triple Therapy Treatment
Emollients
Washing
Topical steroids
Should control more than 95% of cases of eczema
TOPICAL STEROIDS
Under-treatment secondary to
steroid phobia is undoubtedly a common cause of low efficacy
Stepwise approach to treatment
Mild Moderate Severe
Emollients
Mild
potency
topical
steroids
Emollients
Moderate
potency topical
corticosteroids
Topical
calcineurin
inhibitors
Bandages
Emollients
Potent topical
corticosteroids
Topical
calcineurin
inhibitors
Bandages
Phototherapy
Systemic
Therapy NICE
2007
FOOD ALLERGIES
• Affects 4-8% children
Affect 4 – 8%
of children
Adverse food reactions
true food allergy non-allergic food hypersensitivity
( Immune mediated ) (food intolerance) ie. Tyramine, lactase deficiency
IgE mediated non-IgE mediated
Johansson et al. Allergy 2001; 56: 813-824
IMMUNE MEDIATED REACTIONS
• Immediate onset (within <1hour) :
IgE mediated - type 1 reactions
• Intermediate onset (1- 24 hours): variable IgE involvement
• Late reactors (1-5 days later):
usually non-IgE mediated - type IV reactions
Immediate onset (within <1hour ):
IgE mediated (type 1)
• Skin: urticaria, angioedema
• GIT: vomiting,cramps,
• CVS: hypotension
• Respiratory: cough, wheeze, stridor, rhinoconjunctivitis and
anaphylaxis
Intermediate onset (1- 24 hours):
variable IgE involvement
• Skin : Atopic eczema, chronic
urticaria, angioedema
• GI: FTT, colic, GOR, bloody diarrhoea, constipation
• Respiratory tract: asthma, adenotonsillar hypertrophy
Late reactors (1-5 days later)
usually non-IgE mediated
•Skin: Atopic eczema
•GIT: vomiting, diarrhoea,
eosinophilic enteropathy
The most common dermatological
feature in allergic reactions to foods in
children with atopic eczema:
• acute, pruritic, erythematous, macular or
morbilliform eruption occurring within minutes of
ingestion.
• The effect of repeated exposure to a food trigger
may cause a worsening of atopic eczema.
EFFECT OF REPEATED
EXPOSURE TO FOOD TRIGGER • 1936 Engman et al
• 2 year old child with atopic dermatitis and wheat allergy
• Child admitted to hospital on wheat elimination diet
• When skin cleared, left leg and left arm were bandaged
• Given two wheat crackers
• Within 2 hours he had intense pruritus
• Next day, typical eczematous lesions except
under the bandages
CONCLUSION Cutaneous reaction to food produced
intense pruritus, scratching and
rubbing leading to:
eczematous skin lesions.
PREVALENCE OF FOOD
ALLERGY IN ATOPIC ECZEMA
(proven by DBPCFC)
30 – 56% children with moderate
or severe eczema have
underlying food allergy
Sampson et al 1985
Roehr et al 2001
• Removal of proven food allergens
can lead to a significant
improvement in the child’s eczema
• Regular follow up is important
• Most children acquire tolerance
WHO SHOULD WE TEST?
• Severe eczema requiring daily topical steroids for control or >20% BSA affected
• Under 2 years of age (especially <12 months)
• Early onset eczema (< 3 months)
Who should we test?
• Infants who are exclusively breast
fed ( 0.5% CMP allergy)
• History of adverse reaction to food
• Presence of other symptoms
associated with food
hypersensitivity eg loose stools,
vomiting, asthma
• Failure to thrive
The Presence of Ig E mediated food Allergy and Poor Weight Gain
in a Series of Children Under Two Years of Age with
Atopic EczemaWoods A. L and Marsden R.A
St. George’s Hospital, SW17 0QT
IntroductionUnderlying Ig E mediated food allergy has been found to be a factor in children with moderate or severe atopic eczema(1). The purpose of this study was to determine the prevalence of IgE mediated food allergy in children less than two years of age with atopic eczema who presented to our Paediatric Dermatology Clinic.
Methods
Twenty-seven children with atopic eczema, under the age of two were studied. Data collected included the weight gain of the children from birth to presentation, nutritional history, total Ig E and specific Ig E measurements and skin prick tests.
Results
ConclusionThis study is limited by its’ size. However, the findings suggest that Ig E mediated food allergy is common in children under two years of age with atopic eczema. Poor weight gain is prevalent in this group of children and Ig E mediated food allergy is seen in the majority of those who are failing to thrive.
This may suggest that poor weight gain is an indicator of underlying food allergy in children under two years of age with atopic eczema.
1. Hill DJ, Hosking CS. Food allergy and atopic dermatitis in infancy; an epidemiologic study Pediatr Allergy Immunol. 2004 15(5):421-7.
Weight Gain in Children
with Atopic Eczema
64%
4%
32%
Poor weight gain Increased weight gain maintained weight centile
88%
12%
IgE mediated food allergy No IgE mediated food allergy
94%
6%
Poor Weight Gain and IgE mediated food allergy
Poor Weight Gain and no IgE mediated food allergy
Poor Weight Gain and IgE
mediated Food Allergy
Percentage of Children with Atopic
Eczema and IgE mediated Food
Allergy
Centile change in weight in children with severe eczema
-5
-25
-5
-23
-2
-17
18
-37
-21-25
-28.9
-15
28
-8
8
-17
17
-53.9
0
35
-43
13
-41
-32
61
25
-27
19.7
2 1
57
31
-12
11
29
10
0
7
35
73
4 1.9
21
-80
-60
-40
-20
0
20
40
60
80
Ce
nti
le c
ha
ng
e
Centile change from birth to presentation Median centile change: -12
Centile change post dietary intervention Median centile change: +10
BrJ Dermatol 2010 vol 163
Supplement 1 pp118-130
88%
12%
IgE mediated food allergy No IgE mediated food allergy
Percentage of Children with Atopic
Eczema and IgE mediated Food Allergy
Weight Gain in Children with Atopic
Eczema
64%
4%
32%
Poor weight gain Increased weight gain maintained weight centile
Poor Weight Gain and IgE mediated Food
Allergy
94%
6%
Poor Weight Gain and IgE mediated food allergy
Poor Weight Gain and no IgE mediated food allergy
Centile change in weight in children with severe eczema
-5
-25
-5
-23
-2
-17
18
-37
-21-25
-28.9
-15
28
-8
8
-17
17
-53.9
0
35
-43
13
-41
-32
61
25
-27
19.7
2 1
57
31
-12
11
29
10
0
7
35
73
4 1.9
21
-80
-60
-40
-20
0
20
40
60
80
Ce
nti
le c
ha
ng
e
Centile change from birth to presentation Median centile change: -12
Centile change post dietary intervention Median centile change: +10
Conclusion
• Ig E mediated food allergy is common
in children under two years of age with
severe atopic eczema.
• Poor weight gain is prevalent in this
group of children
Conclusion
• Ig E mediated food allergy is seen in
the majority of those who are failing to
thrive.
• Poor weight gain could be an indicator
of underlying food allergy in children
under two years of age with atopic
eczema.
WHAT TESTS SHOULD WE DO?
7 MOST COMMON FOOD ALLERGENS IN CHILDREN
• Cow’s milk* 2.5-5%
• Egg * 2.6%
• Peanuts 1.6-1.9%
• Soya* 0.5%
• Wheat* ?
• Fish 0.4%
• Tree nuts 0.2%
* Resolve by age of 5 years
INVESTIGATIONS
• FBC
• Ig E
• Specific IgE to cow’s milk
egg
wheat
soya
peanut
Specific IgE (RAST tests)
• Quantitate IgE in serum directed
against specific allergen
• Positive Predictive Value of 90-95%
• Useful when skin prick tests are not
available
SKIN PRICK TESTS Positive if wheal size is > 3mm greater than saline
negative control
Negative Predictive Value of more than 95%
There is no correlation between wheal size and severity of allergic reaction
SKIN PRICK TESTS
Advantages
•Rapid
•Cheap
•Easy to do
•More sensitive than blood tests
•More specific than blood tests
•Parents can see the response
Disadvantages
•Requires experience to
interpret
•Risk of anaphylaxis:
I in 3000
•Limited value in patients
with dermographism and
extensive eczema
•Commercial food
extracts are often labile
MANAGEMENT Type 1 allergic reactions
1. Refer to the Paediatric Allergy
Department and a Paediatric Dietician
2. Prescribe piriton
3.Consider an epipen
4.Bronchodilator if asthmatic or history
of respiratory symptoms
5.Prescribe alternative formula milk in
Cow’s Milk Allergy
FOODS CAUSING
ANAPHYLAXIS
• Peanuts
• Milk
• Egg
• Shellfish
• Fish
• Tree nuts
• Sesame
INDICATIONS FOR AN
EPIPEN 1. Type 1 allergic reactions to food that cause
anaphylaxis if there is a history of the following symptoms:
• Difficulty/noisy breathing
• Swelling of tongue
• Swelling/tightness in throat
• Difficulty talking and/or hoarse voice
• Wheeze or persistent cough
• Loss of consciousness and/or collapse
• Pale and floppy (in young children)
2. Type 1 allergic reactions to food if the patient has asthma
INDICATIONS FOR AN
EPIPEN
EpiPen
• Dose of adrenaline is 0.01 mg/kg body weight
• EpiPen Jr. Auto-Injector 0.15 mg is recommended for children weighing 15 - 30 kg.
• For children weighing more than 30 kg, Adult EpiPen Auto-Injector 0.3 mg (adult formulation) is recommended.
ADMINISTRATION OF EPIPEN
• Inject the delivered dose into the anterolateral aspect of the thigh, through clothing if necessary.
• Count for 10 seconds with EpiPen in-situ
• Massage area of injection
• In the absence of clinical improvement or if deterioration occurs after the initial treatment a second injection may be necessary.
• The repeated injection may be administered after about 5 - 15 minutes.
• Patient should be advised always to seek medical help immediately.
ALTERNATIVE FORMULA MILKS
• Extensively Hydrolysed Formulas- EHF
Nutramigen, Pepti
• Amino Acid Formulas – Neocate LCP,
Neocate Advance
• Soya Formulas – Infasoy, Wysoy
Extensively Hydrolysed Formulas-
EHF – (Nutramigen, Pepti)
for uncomplicated non-IgE mediated cow’s milk
hypersensitivity- mild eczema/
gastro-oesophageal reflux
Amino Acid Formulas – Neocate
For severe cow’s milk protein
hypersensitivity –
Severe eczema
Anaphylaxis
GI symptoms
Failure to thrive
Soya Formulas ( Infasoy, Wysoy)
• Children over 6 months only if EHF
or amino acid formulas not
tolerated
• 30-60% of milk allergic children
are allergic to soya
SUMMARY
Consider food allergy in:
Less than 2 years of age
Severe eczema ( daily steroids )
Even if exclusively breast fed
WHERE SHOULD YOU REFER?
• Type 1 food allergies Paediatric
Allergist and Paediatric Dietician
• Severe eczema requiring potent topical
steroids to body or moderately potent
topical steroids to face Dermatologist
REFERENCES • Sampson H et al Food Hypersensitivity and Atopic Dermatitis: Evaluation of 113 Patients.
Journ Pediatr 1985 107:669-675
• Roehr C C et al Children with Food Allergy Presenting as Atopic Dermatitis Compared with Patients with Food Allergy and Gastro-intestinal Symptoms
• Paediatr Allergy Immunol 2001 Apr; 12(2):112
• David T J The Role of Dietary Restriction in Atopic Dermatitis • Textbook of Paediatric Dermatology by J Harper, A Oranje, and N Prose • Baumer J H Atopic eczema in children, NICE. • Arch Dis Child Educ Pract Ed. 2008 Jun;93(3):93-7 • Cox H E Food Allergy as Seen by an Allergist
• Journ Ped Gastro Nutr Nov 2008; 47 Suppp 2: 545-548
• NICE Food Allergy in Children and Young People February 2011
• Ludman S, Shah N and Fox A T Managing Cow’s Milk Allergy in Children
BMJ 2013; 347