Allergic Rhinitis, Asthma, COPD Flashcards
Exaggerated response to antigen
Hypersensitivity
Type of antigen that enters the body
Exogenous
Any substance that induces the immune system to produce antibodies against it
Antigen
Blood group antigen
Endogenous
Normal proteins or complexes that are recognised by the immune system of someone with an autoimmune condition
Auto-antigen
A type of antigen that produces abnormally vigorous immune response
Allergen
IgE mediated release of histamine, mast cells, and basophils
Type 1: Allergic reaction (immediate hypersensitivity)
Reaction within 1 hour
Type 1: Allergic reaction (immediate hypersensitivity)
Ex: Bee sting, latex allergy, medications (penicillin), urticaria, anaphylaxis, atopy
Type 1: Allergic reaction (immediate hypersensitivity)
Treatment for Anaphylaxis
Epinephrine
Genetic tendency to develop allergic diseases such as allergic rhinitis, asthma, and atopic dermatitis
Atopy
Allergic disease in atopy
Allergic rhinitis, asthma, atopic dermatitis
Involves IgG and IgM bound cell surface antigens
Type 2: Cytotoxic reaction
Hours to days rxn
Type 2: Cytotoxic reaction
Ex: Hemolytic reactions (bursting or destruction of RBC) with medications (ex. Sulfa drugs such as cotrimoxazole cause hemolytic anemia), graft rejections
Type 2: Cytotoxic reaction
Involves circulating IgG and IgM immune complex that deposits in post capillary venules
Type 3: Immune complex reaction
1-3 weeks rxn
Type 3: Immune complex reaction
Example: SLE, Serum sickness
Type 3: Immune complex reaction
Cell mediated immunity
Type 4: Delayed hypersensitivity
Mediated by T-cells rather than antibodies
Type 4: Delayed hypersensitivity
Example: Mantoux test
Type 4: Delayed hypersensitivity
Ex: nickel (cancerous) allergy, SJS, poison ivy
Type 4: Delayed hypersensitivity
Poison ivy due to Urushiol, can cause
Contact dermatitis
Involves inflammation of nasal mucous membranes in sensitized individuals when inhaled allergenic particles contact mucous membranes and elicit a response mediated by immunoglobulin E (IgE).
ALLERGIC RHINITIS
Mediators of immediate hypersensitivity
Histamine, leukotrienes, prostaglandin, tryptase, kinins
_________ produces rhinorrhea, itching, sneezing, and nasal obstruction
Histamine
Allergic rhinitis:
Response lasting <4 days/ week or <4 weeks per year
Intermittent
Allergic rhinitis:
Response lasting >4 days/week or >4 weeks/ year
Persistent
Allergic rhinitis:
Symptoms that do not interfere with quality of life
Mild
Allergic rhinitis:
Symptoms that interfere with quality of life such as sleep disturbance and work performance
Moderate to severe
Occurs in response to specific antigens present at predictable times of the year
Seasonal (hay fever) allergic rhinitis
Occurs year-round in response to nonseasonal allergens and usually causes more subtle, chronic symptoms.
Persistent allergic rhinitis
dark circles under the eyes
allergic shiners
safer and more generally accepted than
intradermal testing
Percutaneous testing
can detect IgE antibodies in the blood that are specific for a given antigen, but it is less sensitive than percutaneous tests
radioallergosorbent test (RAST)
effective in preventing the histamine response but not in reversing its effects after they have occurred
H1-receptor antagonists
more effective when taken 1 to 2 hours before anticipated exposure to the offending allergen
Antihistamines
sympathomimetic agents that act on adrenergic
receptors in nasal mucosa
Decongestants
may occur with prolonged use of topical agents (>3–5 days)
Rhinitis medicamentosa
has replaced pseudoephedrine in many nonprescription antihistamine–decongestant
Phenylephrine
relieve sneezing, rhinorrhea, pruritus, and nasal congestion with minimal side effects
Intranasal corticosteroids
They reduce inflammation by blocking mediator release, suppressing neutrophil chemotaxis, causing mild vasoconstriction, and inhibiting mast cell–mediated, late-phase reactions.
Nasal Corticosteroids
mast cell stabilizer, is available as a nonprescription nasal spray for symptomatic prevention and treatment of allergic rhinitis
Cromolyn Sodium
It prevents antigen-triggered mast cell degranulation and release of mediators, including histamine
Cromolyn Sodium
The most common side effect of Cromolyn Sodium
local irritation
anticholinergic agent that may be useful in persistent allergic rhinitis
Ipratropium bromide
It exhibits antisecretory properties when applied locally and provides symptomatic relief of rhinorrhea.
Ipratropium bromide
leukotriene receptor antagonist approved for treatment of persistent allergic rhinitis in children as young as 6 months
Montelukast
considered third-line therapy after those agents
Montelukast
Adr of decongestants
Anorexant
process of administering doses of antigens
responsible for eliciting allergic symptoms into a
patient
Immunotherapy
A chronic allergic disorder characterized by episodes of severe breathing difficulty, coughing, and wheezing using the air passage to narrow and cause shortness of breath
Asthma
The inflammation is due to bronchi hyper
responsiveness to a variety of stimuli
Asthma
Induces a thickened, engorged, edematous airway wall and narrowing of the air lumen.
Plasma protein leakage
Migrates to the airways and release inflammatory mediators
Eosinophils
Release cytokines from type 2 T-helper cells that mediate allergic inflammation
T- lymphocytes