Allergies occur when your immune system reacts to a foreign substance—such as pollen, bee venom or pet dander—that causes symptoms that involve your skin, sinuses, airways or digestive system. Children who are experiencing shortness of breath, wheezing, itchy eyes, a runny or congested nose and swollen sinuses may have allergies. The severity of allergies varies in children and can range from minor irritation to anaphylaxis — a potentially life-threatening allergic reaction to an allergen, causing a constriction of the trachea, preventing breathing. While allergies can't be cured, a number of treatments can help relieve allergy symptoms.
Miller Children’s Hospital uses allergy tests to identify allergens that may be causing the child's allergy symptoms. The allergists at the Pulmonary, Allergy and Cystic Fibrosis Center can then decide what type of medications, if any, and treatments may be needed. By identifying these allergens, changes can be made in the child’s home and living space to potentially improve their health.
There are four types of allergy tests:
Puncture allergy testing
The most common type of skin test is the puncture allergy test, where tiny drops of purified allergen extracts are pricked or scratched into the child’s skin’s surface. This test is usually performed to identify allergies to pollen, mold, pet dander, dust mites and foods. Children may be tested for as many as 30 environmental allergens during this test. The number could be higher if the child is being screened for food allergies.
Intradermal allergy testing
Intradermal allergy testing is usually performed if the doctor suspects a child is allergic to insect venom or penicillin. During this test, small amounts of purified allergen extracts are injected with a small needle syringe into the arm of the child’s skin.
A child having this test can be tested for up to 14 allergens, each requiring individual injections. A small reaction (similar to a bug bite) will appear within approximately 15 minutes if the test is positive. The child may experience some mild discomfort with "itching" from the testing.
Patch allergy testing
This test is usually performed to identify substances that cause contact dermatitis. These include allergies to latex, medications, fragrances, preservatives, hair dyes, metals and resins. This test doesn't use needles. Instead, an allergen is applied to a patch, which is then placed on your child’s skin.
A radioallergosorbent test (RAST) is an allergy test that involves collecting blood. A RAST can be performed when a skin test — the more common allergy test – cannot be done due to a skin problem. RAST tests look for substances in the blood called antibodies. These tests are not as sensitive as skin tests but are often used for people who have sensitive skin and are not able to have skin tests.