[45] Food Allergy

Question 1

What are food allergies?

Answer 1

An abnormal immunological response to food

Question 2

What happens in food allergy?

Answer 2

There is a pathological immune response to a specific food protein

Question 3

What antibody is the usual mediator for an allergic reaction to food?

Answer 3

IgE

Question 4

What is a primary food allergy?

Answer 4

Where children react on first exposure

Question 5

Are food allergies most commonly primary or secondary?

Answer 5

Primary

Question 6

What are secondary food allergies most commonly associated with?

Answer 6

Cross-reactivity between proteins on fresh fruit/veg/nuts and those in pollen

Question 7

What do non-IgE mediated food allergies invovle?

Answer 7

GI disturbance, typically hours after ingestion

Question 8

What is a non-immunological hypersensitivity to food called?

Answer 8

Intolerance

Question 9

What are the most common allergies in infants?

Answer 9

• Milk
• Egg
• Peanut

Question 10

What are the most common allergies in older children?

Answer 10

• Peanut
• Tree nut
• Fish
• Shellfish

Question 11

What are the risk factors for developing food allergies?

Answer 11

• Family history
• Vitamin D deficiency
• Obesity
• Hygiene hypothesis

Question 12

What are the symptoms of IgE mediated food allergies?

Answer 12

• Urticaria
• Facial swelling
• Anaphylaxis

Question 13

When do symptoms of IgE mediated allergic reactions to food occur?

Answer 13

10-15 minutes after ingestion

Question 14

What are the symptoms of non-IgE mediated food allergies?

Answer 14

• Diarrhoea
• Vomiting
• Abdominal pain
• Faltering growth

Question 15

What is the gold standard investigation for both IgE and non-IgE mediated food allergies?

Answer 15

Double blinded placebo-controlled food challenge

Question 16

What happens in a double blinded placebo-controlled food challenge?

Answer 16

The child is given increasing amounts of food or placebo and should be performed in hospital with full resuscitation available

Question 17

What other tests can be used to check for IgE mediated food allergies?

Answer 17

• Skin prick test

- Measurement of specific IgE antibodies in blood

Question 18

What can be used to look for non-IgE mediated food allergies?

Answer 18

Endocsopy and intestinal biopsy

Question 19

How can food allergy be managed?

Answer 19

• Avoid relevant foods
• Advice from dietician
• Written management plan for reaction
• Antihistamines for mild reactions
• IM adrenaline for severe reactions

Question 20

What are the complications of food allergies?

Answer 20

• Anaphylaxis
• Blood in stools (non-IgE mediated)
• Food protein induced enterocolitis syndrome (non-IgE mediated)