The diagnosis of atopic dermatitis is primarily clinical; thus routine laboratory testing is not recommended. Patients with atopic dermatitis may have elevated serum immunoglobulin E (IgE) levels, but this laboratory finding may also be seen with a variety of other disorders (i.e: asthma, allergies and the hyperimmunoglobulin E syndrome). Thus, elevated serum IgE is not specific to atopic dermatitis.
Allergy testing is not routinely recommended for patients with atopic dermatitis. Allergy testing may be considered in a small subset of patients with moderate to severe atopic dermatitis, and/or a clinical history of allergic reaction following allergen exposure.