rhinitis%20-%20allergic
RHINITIS - ALLERGIC
Allergic rhinitis is a symptomatic disorder of the nose secondary to IgE-mediated inflammation of the nasal membranes induced after exposure to allergens.
Major symptoms include nasal itching, watery rhinorrhea, nasal obstruction/congestion, sneezing and postnasal drainage.
Other symptoms include headache, conjunctival symptoms, eye pruritus, impaired smell and morning cough.
Symptoms can reverse spontaneous w/ or w/o treatment.

Definition

Rhinitis

  • Inflammation of the nasal lining membranes

 Allergic Rhinitis

  • A symptomatic disorder of the nose secondary to IgE-mediated inflammation of the nasal membranes induced after exposure to allergens

Signs and Symptoms

Major symptoms

  • Nasal itching
  • Watery rhinorrhea
  • Nasal obstruction/congestion
  • Sneezing
  • Postnasal drainage

Other symptoms

  • Headache
  • Conjunctival symptoms, eye pruritus
  • Impaired smell
  • Morning cough

Symptoms can reverse spontaneously with or without treatment

Pathophysiology

  • There may be various diatheses for allergic rhinitis sensitization but the most important mechanisms are:
    • Genetic factors 
    • Production of IgE antibody 
  • Most allergic rhinitis are caused by inhalation antigens such as:
    • Dermatophagoides (antigen in house dust) - most common
    • Pollens (eg trees, grasses and weeds) - most common
    • Fungi
    • Pets
  • Two phase reactions:
    • Early phase reaction happens when histamine and leukotrienes are released from mast cells and irritates the sensory nerve endings and blood vessels of the nasal mucosa
      • This irritation causes sneezing, rhinorrhea (watery), nasal mucosal swelling or blockage 
    • Late phase reaction happens when inflammatory cells like activated eosinophils infiltrate the nasal mucosa that are exposed to these antigens
      • Seen 6-10 hours after the exposure to antigens
      • Causes mucosal swelling
Digital Edition
Asia's trusted medical magazine for healthcare professionals. Get your MIMS Respirology - Malaysia digital copy today!
DOWNLOAD
Editor's Recommendations
Most Read Articles
15 Aug 2017
New drug applications approved by US FDA as of 1 - 15 August 2017 which includes New Molecular Entities (NMEs) and new biologics. It does not include Tentative Approvals. Supplemental approvals may have occurred since the original approval date.
04 Aug 2017
Chronic obstructive pulmonary disease (COPD) is the fourth cause of global mortality, with experts predicting a potential future rise in the prevalence rates of COPD. 
11 May 2016

In conjunction with World Asthma Day which falls on 3rd May 2016, MIMS Doctor speaks to a renowned respiratory medicine specialist, Dato' Dr. Hj Abdul Razak Abdul Muttalif, regarding the chronic airway disease.

Pearl Toh, 22 May 2016
Asthma patients on salmeterol, a long-acting beta-agonist (LABA), plus fluticasone inhaled corticosteroid (ICS) combination therapy did not have a greater risk of serious asthma-related events compared with patients receiving fluticasone alone, according to the recent AUSTRI* study.