Allergies and Eczema

Question 1

How should anaphylaxis be managed in children?

Answer 1

Place patient on back with legs raised. If significant respiratory distress allow patient to put themselves in a position of comfort but do not let them stand or sit rapidly. If comatose used left lateral position to avoid caval compressions.

ABCDE
Remove trigger if obvious e.g. bee sting/drug/food

Adrenaline 1:1000
If < 6 years give 0.15ml (150mcg)
If 6 years to 12 years give 0.3ml (300mcg)
Adultescent/Adult give 0.5ml (500mcg)

Give IM and hold pen in place for 10 seconds
Repeats dose after 5mins if no improvement and repeat this until they arrive in hospital. Also give high flow oxygen and fluids

If bronchospasm is occurring then give salbutamol (2.5mg if <30kg 5mg if >30kg).

Question 2

What causes a cow’s milk protein allergy?

Answer 2

Either IgE (CMPA) or Non IgE mediated (delayed and so CMPI). Causes colicky symptoms and gastro oesophageal reflux disease, blood, mucus stools and can falter growth.

Question 3

How does cow’s milk protein allergy present?

Answer 3

Onset can be delayed but usually first 3 months of formula fed
Feeds poorly and colicky
Painful regurgitation and vomiting
Lower GI symptoms
Atopic eczema and urticaria

Question 4

How should you investigate a child you suspect of suffering from cow’s milk protein allergy?

Answer 4

± specific IgE to milk
Ask mother to completely remove cow’s milk from her diet of breastfeeding or from formula fed for a period of time. Go back to previous diet and if symptoms follow this pattern then confirmation of CMPA/I.

Question 5

How should cow’s protein milk allergy be managed once confirmed?

Answer 5

1. Substitute milk to extensive hydrolysed milk/Amino acid formula depending on severity. Not goats’ milk, but soya milk okay after 6 months.
2. Dairy free diet if breast feeding
3. Milk free weaning
4. Milk reintroduction later in life (around 5yrs)

Question 6

What are the most common foods children develop allergies to?

Answer 6

Most reactions are from peanut, tree nuts, milk, egg, fish, shellfish, wheat, and soya.

Question 7

How quickly do allergy symptoms come about and what mediates this reaction?

Answer 7

Symptoms usually appear within 20 minutes of ingestion and nearly always within 2 hours. Can be IgE mediated. Non-IgE mediated or mixed.

Question 8

How can you differentiate between IgE mediated and Non mediated allergies?

Answer 8

IgE mediated – immediate reaction, most persistent into adulthood common foods include milk, eggs, peanuts and tree nuts, fish and shellfish, fruit and vegetables.

Non-IgE mediated – delayed hours to days reaction, resolves earlier many by school age, common foods include milk, soya, wheat, rice and oats.

Question 9

What are the clinical features of an allergy?

Answer 9

Pruritis 
Cutaneous eruption 
Anaphylaxis 
GI symptoms 
Hypotensive symptoms 
Angio-oedema of the skin 
Often family history of allergies and atopy

Question 10

How should you investigate potential allergies?

Answer 10

In vitro IgE specific immunoassay
Skin Prick testing
DBPCFC Double blind placebo controlled food challenges (gold standard)

Question 11

What is allergic rhinitis?

Answer 11

Rhinosinusitis is inflammation in the nose, paranasal sinuses causing rhinorrhoea and discomfort. When caused by allergies it is usually seasonal or constant. It is an IgE mediated response due to triggers that stimulate de granulation of mast cells.

Question 12

What are the common triggers of allergic rhinitis?

Answer 12

Pollen (hayfever)
House dust mites
Animals
Mould

Question 13

What are the clinical features of allergic rhinitis?

Answer 13

Sneezing 
Rhinorrhoea 
Bilateral itchy red eyes
Pruritis 
Swollen turbinates 
Post nasal drip 
The allergic salute

Question 14

How should allergic rhinitis be managed?

Answer 14

Allergan avoidance
Nasal saline irrigation
Oral or intranasal antihistamines e.g. cetirizine (preferably non drowsy such as Loratadine)
Intranasal decongestant also useful
If moderate and persistent then intranasal corticosteroid spray (note correct technique involves turning head upside down) – mometasone or fluticasone used
Severe symptoms or life events – short dose of prednisolone e.g. for exams

Question 15

What is eczema?

Answer 15

This is effectively dermatitis. This results in an acute red rash that is poorly demarcated and less scaly than psoriasis. Eczema is itchy, Atopic eczema is the most common type and typically spares the nappy area.

Question 16

What causes eczema?

Answer 16

Genetics
Infection from staph that results in weeping, crusting or pustules
Allergens and specific triggers e.g. food, cow’s milk

Question 17

What are the criteria for diagnosis of eczema?

Answer 17

Itchy skin plus 3 or more of:

1. Onset before 2 years
2. Past flexural involvement
3. History of generally dry skin (xerosis)
4. Personal history of other atopy (or 1st degree relative if <4yrs)
5. Visible flexural dermatitis

Question 18

How should eczema be managed in children?

Answer 18

Most children grow out of it by 13yrs
Education about what eczema is its causes and safeguarding regarding herpeticum (weeping pustules around the mouth)

Avoid irritants
Emollients and soap substitutes – encourage large volumes 3-4 x a day

Topical steroids – used only for exacerbations applying once a day 30mins after emollient. Start at lowest dose and work up.
Topical calcineurin inhibitors – pimecrolimus or tacrolimus if not controlled with steroids
Bandages

Phototherapy
Systemic treatment in severe cases with azathioprine, ciclosporin or methotrexate

Oral antibiotics for any secondary bacterial infection

Question 19

How does eczema present differently between different ages?

Answer 19

Features
• In infants the face and trunk are often affected
• In younger children eczema often occurs on the extensor surfaces
• In older children a more typical distribution is seen, with flexor surfaces affected and the creases of the face and neck