Allergy Flashcards
What is allergy?
Allergy is not a disease itself, but a mechanism leading to a disease. Or an immunological hypersensitivity that can lead to a variety of different diseases via different patho-mechanisms with different approaches in diagnosis, therapy and prevention.
Allergy therefore presents as a number of diseases.
Cool got it
Allergen
any substance stimulating the production of IgE or a cellular immune response. Allergens are usually proteins, but not always. They can for example be carbohydrates.
Sensitivity
Normal response to a stimulus.
Hypersensitivity
Abnormally strong response to a stimulus.
Sensitisation
Production of IgE antibodies (detected by serum IgE assay or SPT) after repeated exposure to an allergen.
Allergy
A hypersensitivity reaction initiated by specific immuno- logical mechanisms. This can be IgE mediated (e.g. peanut allergy) or non-IgE mediated (e.g. milk allergy).
Atopy
A tendency to produce IgE antibodies in response to ordinary exposure to potential allergens. Strongly associated with asthma, rhinitis, eczema and food allergy.
Anaphylaxis
A serious allergic reaction with bronchial, laryngeal and cardiovascular involvement that is rapid in onset and can cause death.
Food
A substance, whether processed, semi-processed or raw, which is intended for human consumption (including drinks), and any substance used in the manufacture, preparation or treatment of food.
Food allergy
Immunologically mediated adverse reaction to food.
How does allergy present?
Via Major allergic diseases
List the major allergic conditions (8)
- rhinitis or hay fever 2. conjunctivitis 3. asthma 4. Atopic dermatitis or eczema 5. Urticaria 6. Insect allergy 7. Drug allergy 8. Food allergy
What is the predominant pre-school allergic conditions?
eczema and food allergy
Which diseases r rare in young children & increase in prevalence into adulthood?
Rhinitis and conjunctivitis
What is the Allergic march’.
When certain allergies change with change (Either start in childhood and decrease with age or vise versa)
pollen allergies >> whats the allergic match for it
detected initially in young children and then increase with age.
Why is allergy important?
Allergy is common Allergy is associated with significant morbidity Allergy can be fatal
What is food allergy?
how is it classified?
an adverse health effect arising from a specific immune response that occurs on exposure to a food.
Food allergy is classified by immune mechanism into
IgE and non-IgE mediated types.
Food intolerance
numerous and frequently reported adverse responses to foods that do not involve the immune response.
Prevalence of each? And lren and sdults
IgE-mediated reactions have been reported to more than 170 foods, so one can be allergic to any food; but food allergies and hence the prevalence estimates are limited to few foods – the commonest being milk, egg and peanuts. The estimated prevalence is higher in children affecting about 6% compared 1-2% of adults.