ALLERGY SKIN TESTING
Patients suffering from allergy related symptoms
are advised to undergo allergy skin testing. By determining the underlying cause through allergy testing, we are not only able to treat the symptoms but decrease the patient’s sensitivity to an
allergen. Allergy testing is a two part test consisting of both scratch tests and intradermal testing. The scratch test is a very simple screening process that works by scratching the skin with a
small plastic pick with a small amount of allergen extract on it. A positive reaction (red, itchy hive) is indicative of the individual's sensitive to that substance. The intradermal test has the
advantage of being more sensitive. The intradermal test is done by injecting a very small amount of allergen extract between the layers of the skin, just enough to make a small welt. The scratch
tests or the intradermal tests will reveal a local reaction at the site of the test in fifteen minutes if the patient is sensitive to the substance being tested. By testing the skin, we are able
to test for environmental allergies (trees/molds/dust mites/animal dander/weeds), food allergies, medicine (penicillin) and hymenoptera (bees).
Your allergy vaccine vial consists of specific substances to which you are allergic. Each serum is specific to the patient and formulated according to each individual patient's reactivity as determined by his/her allergy skin tests. No two vaccines are exactly the same.
Immunotherapy or “allergy shots” is a very effective treatment used to relieve allergy symptoms from hay fever or allergic asthma by administering injections of substances such as pollens, mold spores, dust mites, animal dander, or insects to which an individual has been found to be allergic by skin testing. The mechanisms of its effect are the subject of ongoing research. However, immunotherapy initiates processes that seem to “turn off” the abnormal immune reaction that we term “allergy”.
Xolair is a new medication used to treat moderate to severe asthma that is uncontrolled by inhaled corticosteroids. It works by uniquely blocking the IgE (allergic antibody) and preventing it from binding with its allergic target (mast cells). It may also down-regulate IgE receptors. Genetech created a monoclonal antibody that blocks the allergic reponse. The patient must have a total Ige of 30IU to 700Iu and be of certain weight to receive this therapy. He or she must also be allergic to perennial allergens such as cockroach, dust mite or cat to be eligible for the treatment. This medication has been shown to decrease exacerbation and hospitilization due to asthma. For further information, please check with the website Xolair.com.
Patch tests can be used to diagnose contact dermatitis (allergic reactions to chemicals such as those found in cosmetics, soaps, detergents, latex, etc.). In this test, the allergist places a test panel complete with 23 different allergens on the back, and checks for a reaction after 48–72 hours. Patients who are allergic to the substance develop a localized reaxtion on the skin.
Spirometry measures lung function, specifically the amount of volume and speed of air that can be inhaled and exhaled. Pulmonary function tests can detect any lung problems caused by a person’s allergies and asthma. Typically these tests are performed when a patient is experiencing shortness of breath, coughing, wheezing, chest tightness or discomfort.
OPEN ORAL FOOD CHALLENGE
Misdiagnosis of food allergy can lead to life-threatening reaction or unnecessary avoidance of foods and psychological distress.
Skin testing and blood tests (RAST) are commonly used methods to determine food sensitivity and allergy along with a detailed history and physical exam.
These screening tests can be very helpful in predicting the likelihood of a reaction but ultimately the only way to make a definitive diagnosis is to feed the patient the suspected food performing a so called challenge test. This type of test is sometimes necessary and is an accepted way to diagnose food allergy. It can be performed in the office but requires close monitoring over a period of 1 to 4 hours depending on each individual case.