Description

  • presence of more than 1 of nasal congestion, rhinorrhea, sneezing, and itching 
  • twelfth most common diagnosis in family physician visits

Types 

  • seasonal allergic rhinitis (SAR, hay fever)
    • common aeroallergen triggers in USA include
      • grasses (timothy, Bermuda)
      • outdoor mold spores
      • weeds (ragweed)
      • trees (birch, oak, maple, mountain cedar)
  • perennial rhinitis
    • common triggers include
      • dust mite
      • indoor molds
      • animal dander
      • pollen in some climates
      • occupational allergens
  • episodic rhinitis (occasional exposure)
  • mixed rhinitis (presence of both AR and non-AR) affects 44% to 87% of patients with AR

Likely risk factors 

  • family history of atopy
  • serum IgE > 100 units/mL < age 6 years
  • higher socioeconomic class
  • atopy
  • air pollution
  • maternal AR and intranasal corticosteroid use during pregnancy 

Possible risk factors 

  • smoking 
  • FLG mutation 

Factors not associated with increased risk 

  • infant vaccinations 
  • pet ownership < age 2 years 
  • antibiotic use before age 5 
  • introduction of solid foods before age 4 months 
  • recurrent otitis media

Factors associated with reduced risk

  • early and long-term exposure to stables and farm milk 

Associated conditions 

  • other atopic disease
    • asthma
    • atopic dermatitis
    • allergic conjunctivitis
  • nasal polyps 
  • sinusitis
  • sleep apnea
  • atherosclerosis
  • oral allergy syndrome 
  • otitis media with effusion 

Causes

  • aeroallergens

Pathogenesis 

  • biphasic IgE type I allergic inflammatory mediator response to aeroallergens
    • immediate response (within minutes of exposure, peaks at 15 to 30 minutes)
      • release of mediators from mast cells
        • preformed (such as histamine, tryptase, chymase, kininogenase, heparin) 
        • newly formed mediators, such as prostaglandins
    • late phase response (starts 4 to 8 hours after exposure, release of cytokines and leukotrienes)

History 

  • Chief concern (CC) 
    • sneezing, rhinorrhea, nasal congestion
    • copious rhinorrhea and sneezing within minutes of exposure to allergen
    • nasal congestion (later)
  • Medication history 
    • assess response to past medications
  • Family history (FH) 
    • assess family history of
      • atopic disorders 
      • chronic sinus complaints or infections, or recurrent bronchitis
  • Social history (SH) 
    • occupational exposure
    • presence of mold and water damage in home

Physical

  • HEENT 
    • nasal findings
      • pale or bluish boggy nasal mucosa (edematous turbinates covered with thin clear secretion)
      • nasal airway obstruction
      • transverse nasal crease (“allergic crease” due to “allergic salute” of hand pushing nose up)
    • throat findings
      • postnasal mucous discharge
      • tonsillar hypertrophy
      • cobblestoning (lymphoid hypertrophy of posterior pharynx)
    • mouth breathing (nasal obstruction)
    • eye exam may show
      • “allergic shiners” (infraorbital venous congestion)
      • conjunctival injection and swelling
      • tearing
      • Dennie lines on eyelids (Dennie-Morgan folds)
    • tympanic membrane dullness
    • rarely high arched palate, overbite malocclusion (adenoid facies)

Making the diagnosis 

  • diagnosis usually based on history and exam
    • typical history includes
    • nasal symptoms
    • seasonal or perennial symptom pattern
    • identification of precipitating factors such as exposure to dust, pollen, or animal dander
    • identification of coexisting atopic conditions
    • physical findings may be slight or absent
  • history may elicit enough information to justify presumptive treatment

Causes of nonallergic rhinitis 

  • vasomotor 
  • gustatory 
  • nonallergic rhinitis with eosinophilia 
  • syndrome (NARES) 
  • atrophic
  • drug-induced
  • rhinitis medicamentosa (topical decongestants or cocaine)
  • infectious 
  • hormonal
  • pregnancy

Complications 

  • sinusitis
  • conjunctivitis
  • sleep apnea/poor sleep
  • high arched palate
  • dental malocclusion
  • school absenteeism
  • impaired cognitive functioning 

Prognosis 

  • in most children, may persist >10 years 
  • in adults mostly chronic with variable severity 

From the September 01, 2016 Issue of Clinical Advisor

Topics:

Allergic Disorders Allergy & Immunology