Some foods, furry animals, dust, mites and pollen are the things most likely to cause allergies. If you often experience itching and reddened skin, it's good to do an allergy test. How do I?
"Allergy testing is necessary. But that was an assortment of similar sensitivity so depending on the person and the environment as well," said Dr. Indra G Mansur, DHES, SpAnd, ILS, of Clinical Immunology and Reproductive Health Lady Pondok Kelapa, when contacted detikHealth on Wednesday (15/05/2013).
Dr. Indra explained, the type 1 reaction can still be seen through the skin tests. As for the type 2, 3, and 4 must be viewed through a blood test to make it more clear.
Allergy testing involves skin tests or blood to determine what substance, or allergen, which can trigger an allergic reaction in a person. Skin tests are usually done because it is faster, reliable, and generally less expensive than blood tests, but both types of tests can be used.
The following types of tests are done for allergies, as reported by WebMD, namely:
Skin test
A small amount of allergen is suspected to be on or under the skin as a reaction develops. There are three types of skin tests:
1. Skin prick test (skin prick test)
This test is performed by placing a drop of solution containing the allergen on the skin, which is done by making scratches or puncture needle to penetrate the skin. If redness, itching in the punctured area (called a wheal), it means that the person is allergic to the allergen. This is called a positive reaction.
2. Intradermal test
During this test, a small amount of allergen is injected into the skin. Intradermal allergy testing can be done when a substance does not cause a reaction in the skin prick test, but is still suspected as an allergen for that person.
Intradermal testing is more sensitive than the skin prick test, but more often positive in people who do not have symptoms in the allergen (false-positive test results).
3. Skin patch test (skin patch test)
For skin patch test, the allergen is placed on the pad (like plaster) applied to the skin for 24 to 72 hours. This test is used to detect skin allergy called contact dermatitis.
Blood tests
A blood test is done to look for substances in the blood called antibodies. Blood tests are not as sensitive as the skin test, but it is often used for people who are unable to perform a skin test.
The most common type of blood test is a test that is used enzyme-linked immunosorbent assay (ELISA, EIA). It measures the blood level of this type of antibody (immunoglobulin E, or IgE) that the body may be made in response to particular allergens. IgE levels are often higher in people who have allergies or asthma.
Other lab testing methods, such as radioallergosorbent testing (RAST) or an immunoassay capture test (ImmunoCAP, UniCAP, or Pharmacia CAP), can be used to provide further information. RAST is a blood test that accurately measure the levels of specific IgE in the blood.