ENT allergy Flashcards
Why are allergies on the increase?
better hygiene
Are IgE specific or general?
specific antibodies against specific allergens
host risk factors
age, hereditary, race
Environmental risk factors
infectious diseases, pollution, diet
occupational risk factors
flour, latex, wood dust
urticaria
hives
What is allergic rhinitis associated with?
asthma, atopic dermatitis
immediate symptoms of allergic rhinitis
sneeze, itch, rhinorrhoea, blockage
Late symptoms of allergic rhinitis
chronic obstruction, hyposmia, hypereactivity
hyposmia
reduced sense of smell
Are you born with allergies or are they acquired?
acquired
Allergen
usually protein
antigen that causes allergic reactions
Why is the mode of transmission of the allergen important?
symptoms
Is allergy a type 1 or type 2 hypersensitivity reaction?
1
Explain the sensitisation and re-exposure of allergies
plasma cells produce IgE which binds to mast cells
mast cells degranulate and release histamine, leukotrienes, prostaglandins, chemotactic factors
What do the mast cell contents promote?
vasodilation, vascular permeability, smooth muscle contraction, leukocyte infiltration
What causes the late phase response of the hypersensitivity reaction?
infiltration of other leukocytes eg macrophages, lymphocytes, neutrophils, eosiniphils
Allergic rhinitis
allergic inflammation of the nasal airways
What route of administration must the allergen pass to cause allergic rhinitis?
inhaled
Classification - ARIA
persistent - >4 days a week or >4 consecutive weeks
intermittent less than this
can be mild, moderate severe depending on affects on sleep, work, school, activities
Diagnosis of allergies
skin test
RAST - blood test
Investigations of allergies
IV serum specific IgE
total serum IgE
nasal allergen challenge
nasal cytology
Important values in RAST
<0.35 = -ve >100 = severe
Treatment of allergies
education - avoidance
pharmacotherapy - antihistamine, steroids, immunotherapy
surgery eg nasal septum deviation correction
