Food Allergy Flashcards
What is food allergy
Food allergy - adverse health effect arising from a specific immune response that occurs reproducibly on exposures to a food
What is food intolerance
Food intolerance - numerous adverse responses to foods that do not involve an immune response
What are the types of adverse food reactions
Immune mediated - IgE mediated or non-IgE mediated
Non-immune mediated - food or host characteristics causing adverse food reactions
Describe IgE mediated food allergies and the common foods involved
IgE mediated food allergies have a varying presenting age. Symptoms have immediate onset and allergy usually persists into adulthood
Common foods include: milk, eggs, peanuts, fish, shellfish, fruit and veg (PFS)
Name some symptoms of IgE mediated food allergies
Skin - pruritis, erythema, acute urticaria, acute angioedema
GI - oral pruritis, nausea, vomiting, diarrhoea, colicky abdo pain
Resp - blocked/runny nose, sneeze, itch, wheeze, cough, difficulty breathing
CVS - pallor, drowsy, hypotensive
Name some IgE mediated conditions and describe some symptoms seen
Urticaria/angioedema - hives, swelling, some Gi but no resp or CVS symptoms
Anaphylaxis - rapidly progressive, multi-system reaction
Food-associated exercise induced anaphylaxis - food triggers if ingestion followed by exercise within 2hrs
Pollen food syndrome - pruritis, mild oedema, hay fever( (associated)
Describe non-IgE mediated food allergies and the common foods causing the food allergy
Non-IgE food allergies have a delayed symptom onset. Usually present in infancy and early childhood
Resolve early then IgE mediated - most by school age
Common foods include - milk, soya, wheat, rice, oats
Name some symptoms of non-IgE mediated food allergies
Skin - pruritis, eczema, atopic eczema
GI - food refusal, food aversion, abdo pain, infantile colic, GORD, loose/frequent stools, blood/mucus in stools, constipation, perianal redness, tiredness, pallor
GORD, eczema and consitpation do not respond to treatment
Name some non-IgE mediated conditions and how they present
Proctocolitis - bright red blood in mucousy stools
Enterocolitis - multiple GI symptoms
Eosinophilic oesophagitis - symptoms caused by oesophageal inflammation and scarring, e.g. dysphagia, food impaction
Food protein-induced enterocolitis syndrome - profuse vomiting leading to pallor, lethargy, shock
Name some common food allergies
Celery
Cereals containing gluten, lupin
Crustaceans, molluscs, fish
Eggs, milk, soya
Peanuts, nuts, seasame seeds
Mustard
Sulphur dioxide/sulphites
How do food allergies change with age
Young children tend to have milk, egg and peanut allergy
Early childhood tends to have soya, wheat, nuts, fish and shellfish allergy
Adolescents tend to have fresh fruit and veg allergy
What are the differences betwee milk allergy and lactose intolerance
Milk allergy is always present by 12mths, never after
Lactose intolerance is caused by a lack of lactase and occurs mostly in adolescents and adults
Lactose intolerance has symptoms around the fermentation of lactose by bacteria, e.g. flatulence, diarrhoea, bloated stomach
Name some tests that can be performed to test for food allergies
Skin prick test - test multiple foods by injecting the suspected allergen beneath the skin and looking for a reaction
Blood specfic IgE - immunoassay to detect allergen specific IgE
Elimination diet - can be done for both IgE and non-IgE mediated
What is the treatment of food allergy
Food exclusion - including exclusion of food groups and formats
Inclusion of food/groups/formats
Label reading
Food reintroductions
Medical advice - emergency management of allergic reaction/anaphylactic reaction
