1. GP REFRESHER 2016 Phil Wylie
ALLERGY UPDATE Key pointers (plus bit extra as talked on this in 2015!)
GP REFRESHER 2016
Phil Wylie

2. 1. Only useful tests for IgE mediated allergy (with few exceptions!)

3. Hypersensitivity Reproducible ALLERGIC HYPERSENSITIVITY
(immunologic mechanism
defined or strongly suspected)
NON ALLERGIC
HYPERSENSITIVITY
(immunologic mechanism
excluded)
IgE MEDIATED
NOT IgE MEDIATED
AUTOIMMUNE
COELIAC
NONATOPIC
ATOPIC
EOSINOPHIL e.g
GASTROENTEROPATHY.
IgG MEDIATED

4. Typical IgE symptoms (type 1 immediate hypersensitivity)
Urticaria
Angioedema
Stridor
Wheeze
Diarrhoea
Hypotension – pale
Tryptase (within 4 hours)

5. “Allergy tests” are not useful for most
RAST/SPT give very similar information (both IgE) Most allergy in preschool group non IgE mediated. Can switch between IgE mediated and non IgE mediated Non IgE mediated: History - ? Food diary Exclusion and challenge Be aware common cross reactants (eg milk and soya) Manage in Primary Care? Refer if suspected IgE mediated – tests useful and challenges, if appropriate, may need to be in hospital

6. 2. What is the natural history of food allergy?

7. Natural history varies with allergen
Prevalence
Peanut, fish allergy 20% resolve
Shellfish, tree nut allergy - persists
Milk, egg, wheat allergy
Age

8. When, where and how to challenge?
Normalise diet as soon as possible
IgE mediated – use SPT/RAST to help decide when and possibly need to take place in hospital
Non IgE mediated (milk, wheat, soya, egg) – consider natural history. When not reacted for period consider challenge.
Challenge at home
Protein ladders – milk, egg, soya

9. 3. What children do I need to consider CMPA in?

10. Non IgE mediated symptoms
2-72 hours after ingestion
Gastrointestinal
Colic, reflux (unhappy subgroup), loose stools, perianal redness, constipation, blood/mucus in stools in otherwise well infant
Skin
Pruritus, erythema, AE
“Catarrhal” airway symptoms

11. No tests
Can be managed in primary care (3% population)
Exclusion and challenge (Nutramigen)
Dorset wide guideline (useful flowchart)
Gives dietetic advice (no need see dietician), recipes to manage dairy free diet in toddler’s, advice on normalising diet in due course etc

12. 4. What is not allergic? Lactose intolerance
Lactose is a sugar not a protein
Confusion with CMPA (“lactose free” contains CMP)
Different symptoms – bloating, diarrhoea
Usually temporary in paediatrics post gastroenteritis
20% UK population feel they have problem with milk but most don’t have clinical evidence lactose malabsorption (milk important source calcium, vit D, iodine etc)
Lactase concentration will be low after period of dairy exclusion

13. FODMAP
Fermentable, Oligo, Di, Monosaccarides And Polyols
Simple and complex sugars in variety fruit/vegetables/milk/wheat > unaltered to colonic bacteria
Symptoms bloating, abdominal pain, loose stools
If suspected need dietetic input if beyond exclusion few foods
? Role in toddler’s diarrhoea (sorbitol)
Reactions to chemicals, E numbers etc in food
Gluten sensitivity (excluding coeliac/wheat allergy)
A2 milk – A2 beta casein, contains lactose. A1 beta casein incomplete digestion to form opiate BCM-7 > GI/skin/neurological symptoms

14. 5. Who should get Epipen?

15. Is severity of future reaction predictable?
Many factors will influence severity of reaction such as intercurrent infection, exercise, amount of allergen ingested etc etc
Not going to get worse after each exposure
Tests don’t help you predict severity of future reactions

16. Risk factors for predicting severe reactions/life threatening anaphylaxis
Severity symptoms of previous exposures
Severe symptoms with only minimal exposure
Co-existing asthma – inhaled steroids (particularly if poorly controlled)
Age especially teenagers
Risk taking behaviour (low in preschool group)
Remember risk death is extremely low (smaller than being killed by lightening). Please delay decision to prescribe Epipen until seen in clinic (Phil Wylie allergy clinic?)

17. Emergency drugs in anaphylaxis?
A. Steroids, adrenaline, antihistamine
B. Oxygen, adrenaline, antihistamine
C. Steroids, antihistamine, adrenaline, ventolin
D. Adrenaline, ventolin, oxygen
E. Antihistamine, steroid, adrenaline

18. 6. Can we prevent food allergy developing in the first instance?

19. Why does immune system become primed?
Route
Gut – usual way proteins enter!
Skin – unusual – relevant when have “leaky skin” (eg eczema)
Amount – tiny amounts protein sufficient (eg in dust, creams etc)
(Genetics)
Animal models/population studies

20. LEAP study – LEarning About Peanut
High risk peanut allergy – AE or egg allergic
Peanut avoidance vs peanut ++ from recruitment (4-11 months)
EAT study (Enquiring About Tolerance) looking at cow’s milk, egg, wheat, sesame, fish, peanut (introducing at 3 months)
HEAP study - egg

21. Applying LEAP now? Avoid eczema developing if possible
Treat it aggressively in babies if it occurs (emollient +++) to try and keep skin in good condition
SPT for peanut and cashew before weaning and introduce if negative (eg peanut/cashew nut butter, Bamba snacks)

22. 7. Is recurrent acute urticaria due to food allergy?
Accurate diagnosis
Most burns out within a few months
Role of viral infection
Are tests useful?
Symptomatic treatment – cetirizine can be used up to 4x dose in BNFc (? More effective if used preventative rather than as treatment after symptoms occurred)

23. 8. What is pollen-food allergy syndrome?
Hayfever
40% of hay fever sufferers who are allergic to birch or grass pollen will have this symptom
Birch – apple, hazelnut, carrot, pear, tomato, celery, potato, peach
Grass – melon, orange, tomato, wheat
Perioral and not dangerous
Disappear if food cooked
REASSURANCE all that is needed

24. 9. What is the Dorset Paediatric Vanguard Project?
Patient empowerment – self management
Admission avoidance
“Hot phone” for advice
GP<>Consultant discussions
Urgent access clinic
PAU with CCN outreach
“Care close to home”

25. WE NEED YOUR VIEWS PLEASE
Supporting Primary care
Patch working
More educational events
Clinics in Primary care clinics
Advice and guidance for non-urgent problems (Bridport locality pilot)
WE NEED YOUR VIEWS PLEASE

26. 10. What is Wessex Healthier Together?
Wealth of information for families, health care professionals ( ) App/android
6 pathways for common conditions
Fever in children < 5 years
Abdominal pain
Asthma/wheeze
Diarrhoea and vomiting
Bronchiolitis
Head injury

27. Any questions?