Allergic Rhinitis

Print
Category: Allergic Rhinitis and Sinusitus Published on Thursday, 03 July 2008 Written by Yong Tsai, MD
Share

Anne, a 28 year old musician, has experienced increased sneezing with a runny and stuffed nose, for more than ten years, particularly worse in the fall.  She wonders "Am I allergic to something in the air?"

Defined as an "abnormal sensitivity to substances such as pollen, food, medication or insect sting, an allergy is normally well tolerated and generally considered harmless.  This means that while certain substances, as a rule, do not affect most people, they can induce an adverse reaction (allergic reaction) in others, mainly due to the presence of IgE antibody.

When your nasal mucous membranes become inflamed, medically known as rhinitis, symptoms such as nasal stuffiness, a runny nose, and difficulty breathing through the nose occurs.  While there are several types of rhinitis, approximately 50 to 70% of Americans suffer from allergy-induced rhinitis. 

Allergic rhinitis usually affects patients with a genetic predisposition to become sensitized to airborne substances such as ragweed, tree and grass pollens, dust mites, cat or dog dander.  Usually, allergic rhinitis emerges at a young age, and in patients with a strong family history of atopy, a term used to describe a group of patients who have a personal or family history of one or more of the following conditions:  allergic rhinitis/hay fever, asthma, or eczema.

While allergic rhinitis can be purely seasonal, symptoms can also occur year round, depending on the offending allergens.  Patients who are allergic to grasses, trees, and ragweed frequently have seasonal symptoms, however, people who are allergic to dust, mold, or animal dander, commonly experience perennial symptoms. 

In order to identify offending allergens, your allergist must first review your history and perform a physical examination.     Then, skin testing will be performed, by applying small amounts of allergens on the skin and pricking it.  Within fifteen minutes, results from skin testing are apparent and show a reaction by producing  a "wheel" or round red raised area at the particular allergen's site.  In Anne's case, her skin tests were positive to ragweed and dust mite.

Therefore, Anne has perennial allergic rhinitis with seasonal worsening, caused by dust mites and ragweed.  She inherited the ability to produce IgE  to ragweed and dust mite that bound themselves to the surface mast and basophil cells in the lining of her nose.  After being re-exposed to ragweed and dust mites, the mast and basophil cells immediately released a variety of potent chemical mediators (histamine, leukotriens and prostaglandins) which induced allergic symptoms: itching, sneezing, runny nose and stuffy nose.

Anne was treated with antihistamines and a nasal corticosteroid spray, instructed in the principles of allergen avoidance, and explained her option of immunotherapy (allergy injections) in the event that the medication did not control her symptoms.

Hits: 2088