SM 184a - Allergic Rhinitis Flashcards
Which medications for allergic rhinitis cross the blood-brain barrier?
What is the effect?
1st generation pral antihistamines
-> sedation, increased risk of dementia
2nd generation oral antihistamines do not cross the BBB
Allergic rhinitis affects _____ to ______ of adults worldwide
Allergic rhinitis affects 10%** to **30% of adults worldwide
What is the first line of defense against allergic rhinitis?
Avoidance
(But nasal steroids are the best medications)
What is the definition of rhinitis?
Inflammation of the mucous membranes mostly in the nose but can be in the eyes, throat, sinuses and ears giving rise to symptoms of nasal congestion, rhinorrhea, sneezing and pruritus (itching)
What are the quickly made mediators of allergic rhinitis?
- Leukotrienes
- LTC4, LTD4
- Inrease mucous production
- Prostaglandins D2
- Vasodilation
- Platelet activating factor
- Eosinophil chemotaxis and cell migration
What are the risk factors for allergic rhinitis?
- Family history of atopy/allergies
- IgE > 100 IU/mL begore age 6
- Higher socioeconomic status
- Aeroallergen sensitization (positive allergy skin prick test)
In allergic rhinitis, nasal mucosa and secretions are usually in color
In allergic rhinitis, nasal mucosa and secretions are usually clear in color
What is the DDx for nasal polyps/masses?
- Bilateral
- Samter’s Triad
- Asthma, aspirin sensitivity, nasal polyps
- Cystic fibrosis
- Allergic fungal sinusitis
- Samter’s Triad
- Unilateral
- Nasopharyngeal cancer
In Chicago, what are the peak allergy seasons for…
Trees:
Grass:
Ragweed:
Trees: March-April
Grass: May-July
Ragweed: Mid August-September
What are the early phase symptoms of allergic rhinitis?
Sneezing
Itching
Rhinorrhea and congestion
_____ of children worldwide have allergic rhinitis
40% of children worldwide have allergic rhinitis
What are the major categories of treatment of allergic rhinitis?
Avoidance
Medications
Immunotherapy
Describe the process of allergic sensitization
- Antigen presenting cells bind to a foreign antigen
- The APC presents the antigen to T cells
- Activated T cells induce B cells to differentiate into plasma cells that release IgE specific for the antigen
-
Reexposure
- Pre-formed IgE on mast cells come in contact wtih the antigen again
- Inflammatory cascade occurs
Describe the inflammatory cascade that occurs upon re-exposure to an allergen
- Pre-formed IgE on mast cells come in contact wtih the antigen again
- Inflammatory cascade occurs
- Immediate
- Pre-formed and quickly made mediators are released
- 4-8 hours
- Late phase mediators are released
- Immediate
What are the pre-formed mediators?
When are they released?
- Histamine
- Tryptase
- Chymase
- Kinins
- Heparin
They are released immediately upon IgE crosslinking on mast cells