Allergic rhinitis affects about 1/3 of the US population. Morbidity from this disease leads to decreased productivity, lost work/school days, and increasing costs of medical care and treatment. It is an important entity for the practicing otolaryngologist because many of these patients have failed medical management. In order to treat these patients, allergy testing may need to be performed in order to start vaccine immunotherapy.
Inflammation of the membrane lining the nose secondary to hypersensitivity to aeroallergens, characterized by rhinorrhea, sneezing, pruritis, congestion, post nasal drip and associated conjunctival, otologic or pharyngeal inflammation. These symptoms can be episodic, seasonal or perennial. Severity ranges from mild, to seriously debilitating with excess days of missed school or work. Risk factors include family history of atopy, serum IgE > 100 IU/ml before age six, higher socioeconomic class, exposure to aeroallergens, presence of positive allergy skin prick test.
Prick/scratch testing (SPT) is a superficial skin reaction that does not penetrate dermis. It is highly specific, sensitive, convenient and safe. A test is positive if there is a wheal and flare reaction which is greater than or equal to the histamine control.
Intradermal testing (IT) a dilute antigen extract is injected into the dermis, and a superficial wheal forms. After ten minutes, the wheal is measured again to see if there was any progression. If the diameter of the wheal has increased by 2mm or greater, then a positive response has occurred. This causes relatively minimal patient discomfort.
Immunotherapy is a viable option for patients not benefiting from traditional medical management (eg. nasal steroid spray, antihistamine, etc.) that works by altering one’s immunologic response. Adjuvant therapies may be useful to maximize effect of immunotherapy.
Source:
Medical Management of Allergic Rhinitis UTMB Dr. Quinn's online textbook of Otolaryngology [Apr 30, 2009]
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