Flashcards in CM: Food Allergy Deck (13)
What is the difference between immune mediated and non-immune mediated rxns to food?
immune-mediated = allergy (IgE mediated, non-IgE mediated, or mixed)
non-immune mediated = food intolerance
What is the pathophysiology of allergic rxn to food?
proteins absorbed through gut mucosa and taken up by M cells - APCs take and process it - present in on MHC II to T cells
non-allergic person gets Th1 response
allergic gets Th2 --> IL-4, 5, 13
B cells then stimulated to make IgE specific for food, binds to mast cells and basophils - cross-linked on re-exposure and cells release inflammatory contents
What are the signs and symptoms of an allergic rxn?
sneezing, nasal congestion, rhinorrhea
hoarse voice, dyspnea, cough, wheeze
flushing, urticaria, angioedema
N/V, ab cramping, diarrhea
for IgE mediated - usually occur w/i 20 min and always w/i 2 hrs
What are the 8 most common foods that cause allergic rxns?
milk, egg, peanut, tree nuts, fish, shellfish, wheat, soy
What is the natural history of the 8 most common food allergies?
wheat, soy, milk, eggs all decrease in frequency as children age
children will typically develop tolerance to goods over time (b/w school age and adolescence)
peanut, tree nut, fish and shellfish rarely outgrown and persist throughout life
What symptoms are not indicative of a food allergy?
chronic rhinitis, asthma, behavior or mood changes, autism, headaches, chronic urticaria
What are contributing factors to atopic dermatitis?
temp changes and sweating, decreased humidity, contact w irritants, aeroallergens, microbic agents, food, emotional stress
What is the distribution of skin involvement in infants and toddlers w atopic dermatitis?
eczematous plaques appear on cheeks, forehead, scalp and extensor surfaces
What is the distribution of skin involvement in older children and adolescents w atopic dermatitis?
lichenified, eczematous plaques in flexural areas of neck, elbows, wrists, ankles
What is the distribution of skin involvement in adults w atopic dermatitis?
lichenification in flexural regions and involvement of hands, wrists, ankles, feet and face (particularly forehead around the eyes)
What are features common in all ages w atopic dermatitis?
xerosis = dry, scaly, compromised condition of skin once inflammation resolves
starts w itching, scratching creates pattern of dz
periods of remission and exacerbation
What is the general management of atopic dermatitis?
combo to help w short term flares and long term symptoms
gentle skin care
ID and avoid triggers and irritants
topical corticosteroids for acute inflammation
topical calcineurin inhibitors = 2nd line therapy