Skin Test

Skin test n. A test for detection of an allergy or infectious disease, performed by means of a patch test, a scratch test, or an intracutaneous [more]Skin test - Community and Resources

Noun
1. any test to determine immunity or sensitivity to a disease by introducing small amounts on or into the skin
(hypernym) diagnostic test, diagnostic assay
(hyponym) Dick test

Test done on the skin to identify the allergy substance (allergen) triggering the allergic reaction. A small amount of the suspected allergy substance is placed on the skin. The skin is then gently scratched through the small drop with a special sterile needle. If the skin reddens and, more importantly, swells, then allergy to that substance is probable.

A test for an immune response to a compound by placing it on or under the skin.

If your history, diet diary, or elimination diet suggests a specific food allergy is likely, your healthcare provider will then use either the scratch or the prick skin test to confirm the diagnosis.
During a scratch skin test, your healthcare provider will place an extract of the food on the skin of your lower arm. Your provider will then scratch this portion of your skin with a needle and look for swelling or redness, which would be a sign of a local allergic reaction.
A prick skin test is done by putting a needle just below the surface of your skin of the lower arm. Then, a tiny amount of food extract is placed under the skin.
If the scratch or prick test is positive, it means that there is IgE on the skin’s mast cells that is specific to the food being tested. Skin tests are rapid, simple, and relatively safe.
You can have a positive skin test to a food allergen, however, without having an allergic reaction to that food. A healthcare provider diagnoses a food allergy only when someone has a positive skin test to a specific allergen and when the history of reactions suggests an allergy to the same food.