ESSENTIALS OF DIAGNOSIS
Clear rhinorrhea, sneezing, tearing, eye irritation, and pruritus.
Associated symptoms include cough, bronchospasm, and eczematous dermatitis.
Environmental allergen exposure in the presence of allergen-specific IgE.
Allergic rhinitis is very common in the United States with population studies reporting a prevalence of 20–30% of adults and up to 40% of children. Allergic rhinitis adversely affects school and work performance, costing about $6 billion annually in the United States through direct costs of therapy as well as the indirect costs of sleep deprivation, fatigue and reduced productivity, or absenteeism. Seasonal allergic rhinitis is most commonly caused by pollens and spores. Flowering shrub and tree pollens are most common in the spring, flowering plants and grasses in the summer, and ragweed and molds in the fall. Interestingly, climate change may have an impact on the occurrence of allergic rhinitis since increased temperature and carbon dioxide exposure cause increased pollen production in ragweed plants and since the extended duration of summer correlates with longer periods of pollen production in these and other flowering weeds. Dust, household mites, air pollution, and pet dander may produce year-round symptoms, termed “perennial rhinitis.” A number of different subtypes of allergic rhinitis have been proposed. There is emerging evidence that not all allergic rhinitis can be identified by skin testing, since there appear to be local nasal allergies that can only be detected by nasal challenge testing.
The symptoms of “hay fever” are similar to those of viral rhinitis but are usually persistent and may show seasonal variation. Nasal symptoms are often accompanied by eye irritation, pruritus, conjunctival erythema, and excessive tearing. Many patients have a strong family history of atopy or allergy.
The clinician should be careful to distinguish allergic rhinitis from other types of nonallergic rhinitis. Vasomotor rhinitis (sometimes called senile rhinitis) is caused by increased sensitivity of the vidian nerve and is a common cause of clear rhinorrhea in elderly persons. Often patients will report that they have troubling rhinorrhea in response to numerous nasal stimuli, including warm or cold air, odors or scents, light, or particulate matter. Other types of rhinitis, including gustatory, atrophic, and drug-induced rhinorrhea, have also been described.
On physical examination, the mucosa of the turbinates is usually pale or violaceous because of venous engorgement. This is in contrast to the erythema of viral rhinitis. Nasal polyps, which are yellowish boggy masses of hypertrophic mucosa, are associated with long-standing allergic rhinitis.
A. Intranasal Corticosteroids
Intranasal corticosteroid sprays remain the mainstay of treatment of allergic rhinitis. They are more effective—and frequently less expensive—than nonsedating antihistamines, though patients should be reminded that there may be a delay in onset of relief of 2 or more weeks. Corticosteroid sprays may also shrink hypertrophic nasal mucosa and nasal polyps, ...