An interesting perspective from the American Academy of Dermatology on allergy testing and eczema - 

The role that allergy testing plays in managing atopic dermatitis is often confusing. Allergies can trigger atopic dermatitis, so parents frequently ask if their child should have allergy tests. Concerned parents often believe that if only the allergies could be identified, the child could avoid the allergens. This, in turn, would bring much-needed relief.

The truth is no one thing — not even allergen avoidance — can control atopic dermatitis. Successfully managing this complex condition requires a multi-faceted approach. Proper skin care, using medication as directed, and avoiding common skin irritants such as wool clothing all play a role. For most patients, sticking to this plan keeps atopic dermatitis under control.

For patients with severe atopic dermatitis and those whose condition seems resistant to treatment, allergy testing can be beneficial. An estimated one-third of patients with atopic dermatitis have food allergies. For a few of these patients, eating foods to which they are allergic causes eczema to flare. Why this happens is not entirely clear, but research shows that it most commonly occurs in infants and patients with severe disease.

Click skincarephysicians.com to read the full article.