Allergy: Testing, Treatment Epipens and more

1
Allergy Testing, Treatment Epipens and more!

• Dr Natasha Zurick

2
Frequent Questions

• Why do so many children have allergies these
  days?
• Is the increase real?
• How big is the risk?
• Tricky questions!

3
Answers!

• The increase in allergy is well documented and is
  real
• Why is more tricky a mix of things either in,
  or missing from, our modern lifestyle
• Assessing individual risk of severe reactions can
  be difficult BUT appropriate advice can reduce
  risk and fear.

4
Definitions
5
Food allergy

• 6-8 children have a food allergy in 1st year
• By secondary school prevalence 2
• 7 foods account for gt95 all allergies
• Cows milk, egg, soy, wheat, peanut, tree nuts,
  fish (Europe/USA)

6
Food allergy

• 1-3 children are allergic to cows milk but
  most will outgrow it (80)
• 2-3 children are allergic to eggs again most
  outgrow it or will at least tolerate highly
  cooked egg
• Peanut allergy now 1-2 children most will NOT
  outgrow it (only 20 do)
• New allergies such as kiwi, sesame, lupin seed
  being seen

7
Food Allergy

• IgE mediated
• Important because of possibility of severe
  reactions
• Urticaria, swelling, vomiting, anaphylaxis
• Usually within 30 mins of ingesting food
• Anaphylaxis severe systemic reaction including
  airways or hypotension

• Non- IgE
• Other cells such as eosinophils and t- cells
  involved
• Eczema (also IgE)
• Eg Cows milk protein enterocolitis,proctitis and
  oesophagitis in infants
• Allergy tests negative
• Biopsy diagnostic (but not often needed)

8
Oral Allergy Syndrome

• Symptoms in mouth from IgE to a labile allergen
• Usually also have rhinitis (birch)
• Typically stone fruits, apples
• Fruit OK if cooked
• Teenagers and adults mainly
• Very rare to have more severe symptoms

9
Food and childhood eczema

• Food may contribute in 30
• Significant cause in 10
• Consider if not responding to standard treatment
  (moisturisers and steroids)
• SPT/patch tests often unhelpful
• Diagnosis is by trial of diet MUST try back on
  food even if improve
• Refer to dietician if staying on avoidance diet

10
Gastro-intestinal allergy

• Gastro oesophageal reflux sub group of infants
  improve on CMP free diet
• Colic - sub group of infants improve on CMP free
  diet. Try 1-2 weeks then reintroduce.
• Proctitis (PR bleeding in well infants)
• Protein induced enteropathy and enterocolitis
  (diarrhoea, faltering growth, can be severe)
• Allergic eosinophilic oesophagitis older
  children, persistent GOR and dyphagia
• These conditions usually NEGATIVE IgE/ SPT
• Generally improve in 72 hrs on diet

11
RUH Allergy ClinicWhat we are happy to see

• Any child with an acute reaction to a food eg.
  urticaria, angioedema, oral allergy
• Infants with significant GI symptoms related to
  food (may need general paeds referral) minor
  symptoms may be best seen by the dieticians
• Recurrent urticaria but most not allergy
• Wasp and bee allergies
• Happy to give advice re hayfever, eczema,
  inhalant allergies although most will not need
  a clinic appointment

12
What we do

• Take detailed allergy history tests are only of
  use in context
• Skin prick testing /- blood tests to help
  confirm allergy
• Challenge tests
• Give dietary and general advice
• Monitor for the development of tolerance
• Make decisions re need for EpiPens
• Ongoing advice and support to families

13
Treatment of IgE mediated allergies

• Avoidance of culprit food and awareness of
  hidden allergens
• Good control of asthma
• Management plan and training
• Treatment of reactions antihistamine for minor
  reactions (rash, lip swelling) and adrenaline
  (EpiPen) /- bronchodilators (salbutamol) for
  breathing difficulty or collapse

14
Who needs an EpiPen?NO point if dont carry it
or dont know how to use it.

• Previous severe anaphylactic reaction
• For others depends on a combination of risk
  factors
• Nuts/peanuts
• Asthma needing preventer medication
• Teenagers / over 5s
• Reaction to low dose of allergen
• ? Large SPT/ High specific IgE
• Ease of avoidance of allergen

15
The Future?

• Prevention high risk families
• Oral tolerance regimes?
• Immunotherapy not currently for food (too many
  adverse reactions)
• Sublingual immunotherapy
• Peptide immunotherapy recognised by t-cells but
  dont cross-link IgE
• Anti-IgE (Omalizumab)- maybe to reduce reactions
  to immunotherapy. Regular use??

16
More Information

• The Anaphylaxis Campaign www.anaphylaxis.org.uk
• www.eatwell.gov.uk the food standards agency site
• www.epipen.co.uk or ALK-abello trainer pens and
  info leaflets
• Your Questions answered - Allergy Smith and
  Frew, Churchill Livingstone
• Food Allergy in Children. Postgrad Medical
  Journal. 200581693-701. Baral and Hourihane