Making the distinction between allergic and nonallergic rhinitis What is the best way to distinguish between allergic and nonallergic rhinitis?
Patients with allergic rhinitis are genetically predisposed to producing specific IgE antibodies in response to environmental allergens, such as tree, grass, or ragweed pollen or cat, dog, or dust mite allergens. Patients must have symptoms suggestive of allergies and positive skin or serologic test results that correlate with their symptoms.
Seasonal allergic rhinitis refers to the presence of allergy symptoms triggered by pollen or mold spore allergens during the spring, summer, or fall. These pollen and mold spore seasons vary geographically throughout the United States. Symptoms may include sneezing fits (5 to 10 sneezes in succession); itchiness of the eyes, ears, nose, throat, and palate; runny nose; watery/puffy eyes; nasal stuffiness; postnasal drip; sinus pressure; and fatigue. Triggers include being outdoors during pollen seasons; symptoms are typically worse when patients are outdoors and improve when they are indoors in an air-conditioned climate.
Perennial allergic rhinitis refers to year-round symptoms that are triggered by indoor allergens, such as those from dust mites, cockroaches, mold spores, feathers, and animals. Symptoms include nasal congestion, postnasal drip, sinus pressure/headaches, and ear plugging/popping and may include any or all of the above symptoms of seasonal allergic rhinitis. Often, the patient can determine whether symptoms occur seasonally, perennially, or both.
Conditions such as nonallergic rhinitis (vasomotor rhinitis or nonallergic rhinitis with eosinophil syndrome [NARES]) can mimic allergic rhinitis. Patients with nonallergic rhinitis experience nasal congestion, postnasal drip, headaches/sinus pressure, and ear plugging. However, the results of skin testing for seasonal and perennial allergens are negative.
The triggers for nonallergic rhinitis include weather changes (both temperature and barometric pressure changes); postural changes; irritants, such as smoke, potpourris, perfumes, cleaning agents, solvents, incense, and soaps/detergents. NARES can be differentiated from nonallergic vasomotor rhinitis on the basis of eosinophils present on nasal smear. In addition, patients with NARES may respond better to intranasal corticosteroids than patients who have vasomotor rhinitis.
We found a 96% likelihood that rhinitis was nonallergic in patients who had a late onset of symptoms (after age 35 years); had no family history of allergies; and had no symptoms associated with pets, being outdoors during the spring, or perfumes/fragrances.1
Patients who have components of both allergic and nonallergic rhinitis are said to have mixed rhinitis, which may occur in up to 50% of patients presenting with rhinitis symptoms.