SM 184a - Allergic Rhinitis

Question 1

Which medications for allergic rhinitis cross the blood-brain barrier?

What is the effect?

Answer 1

1st generation pral antihistamines

-> sedation, increased risk of dementia

2nd generation oral antihistamines do not cross the BBB

Question 2

Allergic rhinitis affects _____ to ______ of adults worldwide

Answer 2

Allergic rhinitis affects 10%** to **30% of adults worldwide

Question 3

What is the first line of defense against allergic rhinitis?

Answer 3

Avoidance

(But nasal steroids are the best medications)

Question 4

What is the definition of rhinitis?

Answer 4

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)

Question 5

What are the quickly made mediators of allergic rhinitis?

Answer 5

• Leukotrienes
  
  • LTC4, LTD4
  • Inrease mucous production
• Prostaglandins D2
  
  • Vasodilation
• Platelet activating factor
  
  • Eosinophil chemotaxis and cell migration

Question 6

What are the risk factors for allergic rhinitis?

Answer 6

• Family history of atopy/allergies
• IgE > 100 IU/mL begore age 6
• Higher socioeconomic status
• Aeroallergen sensitization (positive allergy skin prick test)

Question 7

In allergic rhinitis, nasal mucosa and secretions are usually in color

Answer 7

In allergic rhinitis, nasal mucosa and secretions are usually clear in color

Question 8

What is the DDx for nasal polyps/masses?

Answer 8

• Bilateral
  
  • Samter’s Triad
    
    • Asthma, aspirin sensitivity, nasal polyps
  • Cystic fibrosis
  • Allergic fungal sinusitis
• Unilateral
  
  • Nasopharyngeal cancer

Question 9

In Chicago, what are the peak allergy seasons for…

Trees:

Grass:

Ragweed:

Answer 9

Trees: March-April

Grass: May-July

Ragweed: Mid August-September

Question 10

What are the early phase symptoms of allergic rhinitis?

Answer 10

Sneezing

Itching

Rhinorrhea and congestion

Question 11

_____ of children worldwide have allergic rhinitis

Answer 11

40% of children worldwide have allergic rhinitis

Question 12

What are the major categories of treatment of allergic rhinitis?

Answer 12

Avoidance

Medications

Immunotherapy

Question 13

Describe the process of allergic sensitization

Answer 13

• 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

Question 14

Describe the inflammatory cascade that occurs upon re-exposure to an allergen

Answer 14

• ​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

Question 15

What are the pre-formed mediators?

When are they released?

Answer 15

• Histamine
• Tryptase
• Chymase
• Kinins
• Heparin

They are released immediately upon IgE crosslinking on mast cells

Question 16

What is the preferred test to determine what somebody is allergic to?

Answer 16

Skin testing

More sensitive and specific than IgE testing

Question 17

What medication causes beefy, red-hot turbinates bilaterally?

Answer 17

Overuse of topical nasal decongestants

(Should not be used for more than 3 consecutive days)

Question 18

Describe immunotherapy for allergic rhinitis.

How is it delivered?

How long does it take?

Answer 18

Immunotherapy can be used to treat allergic rhinitis to specific, clinically relevant aeroallergens

• Subcutaneous allergy shots
  
  • Building phase
  • Maintenence phase (3-5 years)
  • May prevent the development of sensitization to new aeroallergens
  • May decrease the risk of developing asthma
• Sublingual tablets available for grass, ragwee, dust mites

Question 19

What is the best medication for the treatment of allergic rhinitis?

Why?

Answer 19

Intranasal steroids

(especially good for moderate to severe seasonal allergies)

• Block both the early and late phase mediators of inflammation
  
  • Work best if used consistently
• May also help ocular symptoms

Question 20

Leukotriene Receptor Antagonists are most helpful for which patients with allergic rhinitis?

Answer 20

Patients with…

• Aspirin sensitivity
• Exercise-induced asthma

Question 21

Why is skin testing preferred over IgE testing?

Answer 21

• Skin testing is more sensitive and more specific
• IgE testing cross-reacts with other epitopes and glycoproteins of aeroallergens
• Too much IgE can alter results

Question 22

What conditions are worsened by allergic rhinitis?

Answer 22

Sinusitis

Asthma

Eustachian tube dysfunction

Obstructive sleep apnea

Question 23

Which nasal symptom is specific to allergic rhinitis?

Answer 23

Nasal itch

(not present in non-allergic rhinitis)

Question 24

What are some of the characteristics of non-allergic rhinitis?

Answer 24

• Older age of onset
• Usually less itching/sneezing
• Year-round
• Triggers
  
  • Strong smells, smoke, change in temperature and barometric pressure, alcohol, gustatory

Question 25

What are the late phase mediators of allergic rhinitis? What is their effect?

Answer 25

• Cytokines
  
  • Inflammatory: IL-1, IL-6, TNF-alspha
  • Promote IgE: IL-4, IL-13
  • Promote eosinophils: IL-3, IL-5, GM-CSF
• Chemokines
  
  • RANTES
  • Exotaxin

Cause more nasal congestionn and rhinorrhea

Lead to more fatigue and exhaustion

Question 26

What are some major causes of nasal septal perforation?

Answer 26

• Previous surgery
• Trauma
• Cocaine use
• Connective tissue disease