Inspired by one of our favorite television shows, Allergy Myth Busters looks at a number of popularly held beliefs about allergy.
But are these myths just urban legends or are they true?

MYTH: Children less than 4 years of age can’t be skin tested for allergies.

THE SCIENCE:

First introduced in 1865, allergy skin testing remains the gold standard for diagnosing allergic sensitization. There are two types of skin testing. Skin prick testing involves placing a drop of a suspected allergen (or extract) on the skin and scratching or pricking the surface of the skin. Intradermal testing involves injecting a small amount of extract just under the skin, similar to how a Tuberculin skin test is performed. A positive reaction to either test will appear as a small, slightly raised red bump. Allergy skin testing has a number of positives:

· Quick – Many allergens can be tested at the same time and results are read in 10-15 minutes.
· Comfortable – Both skin prick and intradermal testing involve very minimal discomfort, although positive test can be itchy for several minutes.
· Accurate – When performed with high quality extracts and by a trained technician, allergy skin testing is the most accurate test for allergy diagnosis.

Although the results of allergy tests are not affected by a person’s age, sex, or race independent, certain age (children younger than 2 years and adults older than 65 years) and racial (African American children) factors may affect their interpretation. This fact may explain why some people believe that children need to be a certain age before they can be skin tested. Generally speaking, skin testing can be performed even in infancy, and as young as one month of age. However, the skin of very young children may not be as reactive as older children and adults, and therefore the results need to be interpreted more carefully.

The reason for skin testing is probably more important than the age at which a child is tested.

In infants and toddlers, allergic disease most commonly occurs as food allergy and atopic dermatitis. In school-age children, allergic disease occurs more commonly as allergic rhinitis. Asthma can occur at any age, but occurs most commonly in adolescent boys and teenage girls. Because of this, skin testing should be aimed at identifying allergic triggers appropriate to the age of the child.

Skin testing, particularly prick skin testing, is virtually painless. There is no bleeding involved, as the needle only pricks the skin to the depth of a scratch. The worst part of skin testing is that the skin test sites may be quite itchy when positive results occur.

MYTH BUSTED!
Allergy skin testing is a safe, accurate and virtually painless means of diagnosing allergy at all ages. All Allergy Partners physicians are Board-Certified and experts in the diagnosis, treatment, and management of allergies and asthma at any age. Learn more at allergypartners.com.

William McCann, MD
Asheville, NC