Table of Contents
The test is not completely accurate. In most situations, before testing occurs patients will have tried to avoid any of their known allergens, as well as tried medications, often including nasal corticosteroid sprays. However, patients with more severe symptoms, particularly those with asthma, significant eczema, or nasal polyps, may benefit from earlier skin testing.
Laboratory Tests
Nasal Smear. The doctor may take a nasal smear. The nasal secretion is examined microscopically for factors that might indicate a cause, such as increased numbers of white blood cells, indicating infection, or high counts of eosinophils. High eosinophil counts indicate an allergic condition, but low counts do not rule out allergic rhinitis.
Tests for IgE. Blood tests for IgE immunoglobulin production may also be performed. One test, called the radioallergosorbent test (RAST), is used to detect increased levels of allergen-specific IgE in response to particular allergens. Blood tests for IgE may be less accurate than skin tests. They should be performed only on patients who cannot undergo skin testing or when skin test results are uncertain.
Imaging Tests
In people with chronic rhinitis, the doctor may also check for sinusitis. Imaging tests may be useful if other tests are ambiguous. Computed tomography (CT) scans may be useful for some cases of suspected sinusitis or sinus polyps.
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Click the icon to see an image of a CT scan. |
Nasal Endoscopy
In certain cases of chronic or unresponsive seasonal rhinitis, a doctor may use endoscopy to examine for any irregularities in the nose structure. Endoscopy uses a tube inserted through the nose that contains a miniature camera to view the passageways.
Review Date: 05/03/2011
Reviewed By: Harvey Simon, MD, Associate Professor of Medicine, Harvard Medical
School; Physician, Massachusetts General Hospital. Also reviewed by
David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.
A.D.A.M., Inc. is accredited by URAC, also known as the American Accreditation HealthCare Commission (www.urac.org)
