In order to prevent health complications that arise due to asthma, patient must go through allergy tests. These tests are usually combined with personal history of reactivity to specific allergen in order to diagnose and track growth of asthma. Doctor can also opt out of allergy tests if he can figures out the triggering medium from history itself.
Allergy skin tests are reliable and fast ways for determining condition and growth of asthma. Testing for asthma is usually suggested if there are fair chances of asthma being caused by specific allergen or group of allergens. In the tests, allergens are injected under the skin for identification of immunoglobulin E (IgE) mediated responses. The chemical compound found in people with allergies is responsible for activation of mast cells of skin. Thereafter, these cells release chemicals and causing swelling, or redness, or itching, if a certain level of IgE is found.
Skin Prick Test
In this test, few drops of allergens are dropped on the back skin. Thereafter, a needle is pricked through the skin. Within the space of 15 minutes, a hive will become evident at the portion having IgE antibodies.
One of the common asthma allergy testing methods, intradermal allergy tests are usually used on a negative skin prick testing. In this test, allergen extract is injected into the skin. These are often used with environmental allergens or drugs, but are not done with food allergens or latex. Owing to more risk of inducing a systemic allergic reaction and accuracy aspect, these are not preferred by all.
In an allergy patch test, a specific allergen is applied to the patch and is then placed on your skin. The patch will take 48 hours to take an effect. The result is positive in case skin turns red and itches, the chances are great that you are allergic to the specific allergen.
Radioallergosorbent Test (RAST)
Radioallergosorbent test (RAST) measures IgE reactions to specific triggers causing asthma. Carried out in a test tube, the test is quite effective for individuals who cannot take skin test due to some complications. One of the advantages of choosing RAST over other tests is its non-sensitivity to medications.
Quantitative Immunoglobulin Determination Test
Quantitative immunoglobulin determination test is another comprehensive technique of blood testing for asthma by measuring immunoglobulin or antibody proteins from blood. This helps in figuring out symptom of asthma, which is either an allergy or an infection.
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