Is it allergy? Debbie Shipley

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1 Is it allergy? Debbie Shipley

2 Topics Food Allergy and Eczema Hand Eczema and Patch Testing Urticaria

3 Tackling Allergy Gell and Coombs classification Skin conditions with possible allergic component Allergy presentations

4 Gell and Coombes Type 1 IgE mediated Immediate hypersensitivity Type 2 Antibody dependant cytotoxic hypersensitivity eg GVHD Type 3 immune complex eg vasculitis Type 4 T-cell mediated delayed hypersensitivity

5 Gell and Coombes Food and drug allergy IgE mediated Non IgE mediated Contact Allergy Type 4 T-cell mediated delayed hypersensitivity

6 Common conditions with potential allergic component Eczema Urticaria Drug Rash

8 Allergy presentations I have urticaria- what am I allergic to? I have eczema, can I have a test for food allergy? My infant has mild eczema, what is he allergic to?

9 Discussion Points History Investigation Treatments Uncertainties

11 Allergy presentations I have urticaria- what am I allergic to? Nothing I have eczema, can I have a test for food allergy? No My infant has mild eczema, what is he allergic to? Unlikely to be anything significant

Vesiculation Excoriation In chronic eczema Lichenification

12 Clinical features of Atopic Eczema In acute stage of atopic eczema Erythema Oedema / papulation Oozing / crusting Vesiculation Excoriation In chronic eczema Lichenification Dryness Scaling Cracking / fissuring Post-inflammatory hyper/hypo pigmentation

13 Atopic Eczema (AD/AE) Complex and multi-factorial Barrier dysfunction leads to other atopic phenomena Asthma and hayfever are frequently associated with atopic eczema. Asthma develops in 30% of children with AD and allergic rhinitis in around 35%

14 Genetic Filaggrin gene mutations Environmental Water Irritants Inhaled allergens Food allergens Contact allergens Unhealthy relationship Staph aureus HSV

15 Food Intolerance- Not allergy Non-immune or non-allergic adverse reactions are termed food intolerance Pharmacological reactions to foods are due to chemicals normally present in the foods, e.g., theobromine in chocolate or tyramine in aged cheeses. So too are adverse reactions to food additives such as sodium and potassium sulfites, metabisufites, monosodium glutamate and gaseous sulphur dioxides. Such agents are added to foods and drinks to prevent discoloration and are also used as preservatives in a variety of medications Host factors such as lactase deficiency, which are associated with lactose intolerance, or idiosyncratic responses may be responsible for other non-allergic reactions to foods Toxic reactions to food can occur in anyone provided a sufficient amount of the food is ingested; they are due to toxins in the food, e.g., to histamine in scombroid fish or bacterial toxins in food

16 Food Allergy The term food allergy is used when an immunological mechanism has been defined or is suspected. The two broad groups of immune reactions are IgEmediated and non-ige-mediated IgE-mediated reactions are usually divided into immediate onset reactions (immediate in time) and immediate plus late-phase (in which the immediate onset symptoms are followed by prolonged or on-going symptoms) A severe generalised (Ig-E mediated) allergic reaction to a food is classified as anaphylaxis

17 Food Allergy Non-IgE-mediated reactions, which are poorly defined both clinically and scientifically, are believed to be T-cell-mediated. They are typically delayed in onset, and occur 4 to 28 hours after ingestion of the offending food

18 Food Allergy- Children Up to 8% of children under 3 years may be affected Up to 35% of children with severe allergic eczema experiencing IgE-mediated food allergy About 2.5% of newborn infants have hypersensitivity reactions to cow's milk in the first year of life with approximately 80% outgrowing the allergy by the fifth birthday; about 60% of milk allergic reactions are IgEmediated. Approximately 25% of these infants retain their sensitivity into the second decade of life, and 35% may acquire other food allergies. Studies suggest that % and 0.5% of young children are allergic to eggs and peanuts, respectively.

21 Food Allergy and Eczema- Adults 2% of adults affected by food allergy The role of food allergens as an aggravating factor is less important in adults Pollen-associated food allergens have been suggested as playing a role in up to 15% of severely affected patients with AD Sensitivity to classic food allergens such as milk and eggs has been shown only rarely (7.4%) and often is not clinically relevant

22 Tests IgE RAST Prick tests Patch Tests write a detailed enough letter and they will be triaged to patch test clinic Exclusion Challenge

23 Allergy Consider food allergy in: children who react immediately to a food infants and young children with moderate or severe uncontrolled AD, particularly with gut dysmotility or failure to thrive Consider inhalant allergy in: children with seasonal flares of AD children with associated asthma and rhinitis children over 3 years with AE on the face.

24 Allergy Consider allergic contact dermatitis in: children with an exacerbation of previously controlled atopic eczema children who react to topical treatments. Be reassuring that most children with mild atopic eczema do not need clinical testing for allergies. Advise not to have high street or internet allergy tests

25 Tests IgE RAST Prick tests Patch Tests write a detailed enough letter and they will be triaged to patch test clinic Exclusion Challenge

26 Urticaria Acute urticaria Chronic Spontaneous Urticaria More than 6 weeks No obvious trigger or contributing systemic problem in 90% patients Aggravating factors physical, NSAIDs, stress, foods Investigation FBC, CRP, TSH

27 Treatment Antihistamines Montelukast Prednisolone Ciclosporin Omalizumab

28 Hand Eczema Irritant versus allergic contact dermatitis Barrier integrity and dysfunction Pattern of distribution irritant versus ACD High risk occupations Likely culprits for ACD MI

29 Contact Allergy in AD The role of contact allergy in AD patients is often underestimated. Common sensitizers include metals (nickel sulfate, cobalt chloride, and potassium dichromate) and fragrance Clinical relevance is not always evident The identification of contact allergens is very important because it may influence the clinical course of AD, the patient's occupational choices, and the development of hand dermatitis among those who work in certain occupations (such as hairdressers, cleaners, metalworkers, mechanics, and nurses)

30 Barrier Function threshold for irritancy A threshold for irritancy B hand dermatitis restoring barrier function 1 0

34 Summary Food allergy in children with moderate or severe eczema Contact allergy in people with odd patterns of eczema Drug allergy in patients with recognised reaction patterns and expected timing of onset Chronic urticaria is rarely allergy

Barrier Enhancement for Eczema Prevention (BEEP study) Chief Investigator: Professor Hywel Williams (University of Nottingham) Local Principal Investigator: Dr Matthew Ridd (University of Bristol)

35 Barrier Enhancement for Eczema Prevention (BEEP study) Chief Investigator: Professor Hywel Williams (University of Nottingham) Local Principal Investigator: Dr Matthew Ridd (University of Bristol) Research question Can daily emollient for first year of life prevent eczema in high risk children? (high risk = family history of eczema, asthma or hayfever) Intervention vs control group (Diprobase/Doublebase vs no emollient) Eczema assessment at 24 months, questionnaires at 8 intervals over 5 years Primary outcome: Proportion of infants with a diagnosis of eczema at 2 years old (blinded assessment by clinical studies officer) 35

36 Recruitment in primary care Surgeries sending letters to all pregnant women Docmail Standard search and mail out Search conducted every 6 months for >12 weeks pregnancy Posters and flyers displayed in surgeries Promotion of trial by community midwives and health visitors Recruitment in Bristol to start in Winter 2015 now inviting surgeries to express interest in taking part Contact: beep-study@bristol.ac.uk 36

Food Allergy Testing and Guidelines

Food Allergy Testing and Guidelines Dr Gosia Skibinska Primary Care Allergy Training Day, 15 th October 2011 Food Allergy Testing and Guidelines Food allergy Testing Guidelines Cases Food Allergy NICE