Food allergy referral (Paediatrics guidelines)

Oral-only symptoms associated with raw fruits / vegetables are normally due to pollen food syndrome (PFS, oral allergy syndrome). This is caused by cross-reactivity to birch pollen.

There are three elements needed to make a diagnosis:

1. Oral symptoms ONLY with raw fruit / vegetables (often instant onset of symptoms)
2. Tolerance to cooked fruits
3. Signs of birch pollen allergy (hay fever)

PFS can often be wholly managed in Primary Care.

REFER if reactions to nuts or Anaphylaxis.

BSACI Leaflet for GPs: Pollen Food Syndrome

Based on history, decide which type of allergy you suspect: IgE-mediated or non-IgE-mediated

IgE-mediated symptoms:

• Acute onset (usually minutes, not more than 1 to 2 hours post exposure) and
• AND include one, or a combination of: urticaria, angioedema, rhino-conjunctivitis (rare on its own), wheeze, stridor, repetitive and copious vomiting, sleepiness, collapse
• Any airway involvement or circulatory compromise = anaphylaxis, even if no rash

Most IgE mediated reactions occur immediately and almost all within 1 hour.

Reactions after 2 hours are extremely unlikely to be IgE mediated. In these cases suspect non-IgE-mediated reactions, or manage symptoms of eczema, reflux, etc.

Non IgE-mediated symptoms:

• Delayed / non-acute onset (several hours, up to few days)
• AND at least one of:
  
  • exacerbation of atopic eczema
  • worsening of gastro-oesophageal reflux
  • reproducible abdominal upset (vomiting, loose stools)

Cow’s milk is the most common reason (sometimes soya), other foods are rare.

Often in kids with severe eczema and or multiple / complex allergies.

IgE-mediated:

Acute / chronic spontaneous or inducible urticaria: itchy urticarial rash, no correlation with food and no reproducibility from history. 10 to 40% have angioedema.

Non-IgE-mediated

The conditions below are common and can easily occur WITHOUT non-IgE food allergy being present:

• Gastro-oesophageal reflux
• Constipation (Idiopathic)
• Chronic diarrhoea (consider 'Toddler Diarrhoea')
• Lactose intolerance
• Eczema (many reasons for flare-ups)
• Rhinitis (usually aero-allergens)

Take an allergy-focused history.

Please include the following information below in your referral, using the EATERS mnemonic below:

Exposure by consumption (food eaten), sometimes contact with, and rarely inhalation of, allergen

Allergen: Which food(s) ingested? How much food caused the reaction? Is it a common allergen?

Timing from exposure to symptoms

Environment: where did reaction occur?

Reproducible: has child had that food since or previously with no reaction?

Symptoms and signs in relation to the food exposure: note severity, airway or circulation involved (anaphylaxis).

Also include in your history:

• Feeding history in infants: breast or formula fed / weaning, etc
• Allergic co-morbidities (especially: asthma, eczema, rhinitis)
• Family history of current / past atopy

Suspected Ig-E mediated food allergies

Referral is often NOT needed in the following situations:

• Isolated fruit allergy of any kind (including tomato, citrus, and pineapples, and other irritants like vinegar etc). Reactions to fruit are usually due to contact irritation rather than true allergy, reactions tend to be mild. Refer only if anaphylaxis
• Isolated egg or milk IgE allergy. See: Egg allergy guideline
• Family history of food allergy alone is NOT an indication for testing or referral. If the child has had that food since the event with no reaction, then they are not allergic to that food. Reassure.
• If the child has had that food previously (prior to the event), with no gap in regular consumption, and in good age-appropriate portions, then it is unlikely this reaction is allergy, but refer if uncertain.

Suspected reactions to flavourings, additives, E-numbers are not true immunologic reactions. NB there is no testing for such additives.

Challenging at home (including skin / lip tests) is NOT appropriate for suspected IgE reactions.

Suspected Non-IgE-mediated food allergies

These can often be managed in primary care.

For a diagnosis and treatment plan specific to non-IgE Cows’ Milk Allergy please refer to Highland Non-IgE Cows' Milk Protein Allergy Guideline

Reassure parents that it is not a dangerous allergy

1. Trial elimination of suspected allergen for 2 to 4 weeks.
   If the child does not improve, then allergy is unlikely.
2. Re-introduce that food.
   If child does improve, then worsens on re-introduction of food, make the diagnosis and advise avoidance.
   Paediatric dietitian referral may be considered if doubt about nutritional adequacies of diet or timings of food re-introduction

Treat for reflux / constipation / eczema, bearing in mind commonality of these conditions without food allergy being present.

Testing

Parents may bring their child in with results of private / on-line allergy testing (eg, hair analysis, serum-specific IgG testing, etc). These are NOT recommended and have NO evidence for their utility. It is best to gently counsel regarding this, take an allergy-focussed history, acknowledge parental concern, formulate a clear plan together and direct to resources such as Allergy UK: Food allergy testing and diagnosing.

Serum IgE cannot distinguish between sensitisation and true allergy, so testing for a wide panel of allergens is NOT recommended.

IgE-mediated:

• Any child who has had a significant IgE-mediated reaction to a small amount of food
• Anaphylaxis to food: Prescribe / train on the use of adrenaline auto-injector.
  See CYANS: Diagnosis and Management of Food Allergy and Highland Formulary: Anaphylaxis
• Multiple IgE-mediated food allergies
• Concurrent IgE-mediated food allergy and diagnosed asthma on preventers, or poorly controlled asthma

Non-IgE-mediated:

• Impacting on child’s diet: Refer to Dieticians in first instance.
• Child has faltering growth on serial weights due to non-IgE allergy (this is rare)
• Clinical suspicion of multiple food allergies after trial eliminations and re-introductions (usually children with severe eczema and gut symptoms)
• Persisting parental suspicion of food allergy, despite lack of supporting history (especially in children or young people with difficult or perplexing symptoms)

• EpiPen - Audio and Video - (emc) (medicines.org.uk)
• Emerade - Risk Management Materials - (emc) (medicines.org.uk)
• Jext - Risk Management Materials - (emc) (medicines.org.uk)

• CYANS: Diagnosis and Management of food allergy

• Children and Young People's Allergy Network Scotland