Allergic Rhinitis

IgE-mediated allergic reaction (type I hypersensitivity)

Aetiology

Intermittent

  • Symptoms <4 days per week or symptoms for <4 weeks
  • Grass pollen, tree pollen, fungal spores

Persistent

  • Symptoms >4 days per week AND >4 week duration
  • House dust mite, cat, dog

Pathophysiology

  • IgE-mediated allergic reaction (type I hypersensitivity) results in the generation of histamine and leukotrienes

Classification

  • Mild - does not affect patient's day to day life significantly)
  • Moderate-severe - involves e.g. abnormal sleep, impairment of daily activities, missing school/work
  • This is in untreated patients

Clinical presentation

  • Sneezing, nasal itching, nasal discharge and nasal congestion
  • Allergic crease indicates repeated itching of nose
notion image

Investigations

If diagnostic doubt:
  • Skin prick test
  • Measure blood IgE

Management

  1. Allergen avoidance
  1. Symptomatic therapy
    1. Anti-histamines e.g. cetirizine
    2. Topical corticosteroids e.g. beclomethasone
    3. Topical steroids + antihistamines
  1. Immunotherapy for selected patients - LTR blockers e.g. montelukast
  1. Surgery for specific indications for relief of obstruction e.g. diathermy for mucosal hypertrophy